Asia-Pacific Dengue Prevention Board
Accelerating Progress in Dengue Control:
Dengue Surveillance in the Asia-Pacific Region
Colombo, Sri Lanka, 21-23 June 2007
A program of:
Opinions expressed this report are not necessarily the oﬃcial opinion of organizations represented in the
meeting, rather the personal opinions of the experts.
This document is a publication of the Pediatric Dengue Vaccine Initiative of the International Vaccine Institute and all
rights are reserved. Photocopying and distribution through the internet and other means for non-commercial purposes are
permitted and encouraged providing all such copies include the following citation: Accelerating Progress in Dengue
Control, Dengue Surveillance in the Asia-Paciﬁc Region. A PDVI publication on behalf of the Asia-Paciﬁc Dengue Preven-
tion Board, Seoul: International Vaccine Institute; 2009.
Fitzsimons, David W.
Mark E. Beatty, M.D., M.P.H
Pediatric Dengue Vaccine Initiative, http://www.pdvi.org/
International Vaccine Institute, http://www.ivi.org/
SNU Research Park, San 4-8 Bongcheon-7-dong
Kwanak-gu, Seoul, Korea 151-919
Electron image of mature Dengue-2 virus particles replicating in five-day-old tissue
culture cells. The original magnification is 123,000 times. (available at
TABLE OF CONTENTS
EXECUTIVE SUMMARY........................................................................... ........... 1
Obstacles and weaknesses………………........................................................ 4
COUNTRY EXPERIENCES.................................................................................... 8
SELF-IDENTIFIED POSITIVE FEATURES OF
COUNTRY SURVEILLANCE SYSTEMS.............................................................10
RECOMMENDED BEST PRACTICES..................................................................17
ANNEX 1: MEETING AGENDA............................................................................21
ANNEX 2: MEETING ATTENDEES ……………………………...…….…….....23
ANNEX 3: MEETING READING LIST..................................................................28
The Asia-Pacific Dengue Prevention Board convened an interdisciplinary meeting for participants
from 11 countries in the Asia-Pacific region to discuss dengue surveillance. The objectives of
the meeting were:  to agree on a common definition of dengue surveillance,  to identify the
purposes for having national and global dengue surveillance,  to identify the stakeholders who
would use dengue surveillance data and review their needs and concerns,  to examine the key
outputs or products of surveillance in relation to the users of these products, and  to undertake
a comparative analysis of surveillance systems between the countries represented at the meeting.
In all 11 countries represented at the meeting, dengue fever and dengue haemorrhagic fever along
with associated deaths are required by laws to be reported to the Ministry of Health. Most
countries monitored and reported clinically suspected cases on a daily or weekly basis. Generally,
surveillance of dengue is not considered adequate for recognizing outbreaks in most countries due
to delays in reporting, insufficient use of laboratory confirmation, and under reporting of cases.
Case definitions vary, and differences make classification of dengue haemorrhagic fever difficult.
Using surveillance data for predictions of outbreaks was considered limited. In addition, since
significant underreporting occurs, estimates of the disease burden of dengue are unreliable based
on surveillance data alone.
After hearing the technical and country presentations, Board discussions led to identification of
best practices for dengue surveillance. These included:  every country endemic for dengue
should have a dengue surveillance system including a quality assurance mechanism; 
legislation should make dengue and dengue hemorrhagic fever a notifiable disease in every
affected country.  The World Health Organization regional case definitions should be
consistently applied for case classification.  Reverse transcription-PCR (RT-PCR) and virus
isolation are the two recommended methods for early virus identification and confirmation of a
dengue infection, (up to 4 days after fever onset). After day 4, IgM-capture ELISA is
recommended.  National and international laboratories should have a computerized network in
order to share their expertise and data (e.g. serotype information, time and place of isolation,
serotype, and case-fatality rate).  Dengue virus data should be properly registered in gene data
banks.  Laboratory methods and protocols should be standardized.  Electronic reporting
systems should be developed and used broadly.  The Asia-Pacific Dengue Prevention Board
should help in developing a standardized reporting format for use by each country in the region
for electronic reporting.  Minimum reporting of aggregate data on dengue should include
incidence rates of dengue fever, dengue hemorrhagic fever and dengue shock syndrome, and
hospitalization rates and mortality rates broken down by age group.  Surveillance systems
should be improved so that users can use the data to detect and forecast dengue outbreaks through
use of a national threshold for outbreak alert and response, and identification and application of
factors that predict outbreaks.  Surveillance systems should monitor the seasonality, age
distribution and transmission patterns, and evaluate and guide the introduction of a potential
vaccine.  Periodic additional studies (e.g. capture recapture) should be conducted to assess
under reporting and the quality of surveillance.  Surveillance data should be used to monitor
intervention programs using disease incidence and/or vector indices to demonstrate effect. The
Board will continue to develop these recommendations and prepare a manuscript describing them
Australia, Cambodia, French Polynesia, India, Japan, Malaysia, Philippines, Singapore, Sri Lanka,
The Asia-Pacific Dengue Prevention Board convened an interdisciplinary meeting for
participants from 11 countries in the Asia-Pacific region to discuss dengue surveillance.1
The objectives of the meeting were to:
develop a common definition of dengue surveillance,
identify the needs for national and global dengue surveillance,
identify the stakeholders in dengue surveillance and review their needs and
examine the key outputs or products of surveillance in relation to the users of
undertake a comparative analysis of surveillance systems,
The meeting concluded with the identification of proposed best practices in various areas
As detailed in this report, each of these objectives was achieved. Specific information
about each is summarized at the end of the report.
The Americas Dengue Prevention Board held a similar meeting on surveillance in
Mexico City in January 2008. A complementary report has been issued.
The two reports of the Prevention Boards provide timely information and guidance about
surveillance and serve as important supplements to the guidelines issued by WHO both
from headquarters and the regions. In addition, these reports provide important guidance
to continued efforts to test, introduce and sustain the use of dengue vaccines in endemic
The context of the meeting was the changing epidemiological picture of dengue. Over
the past years outbreaks of dengue have become more frequent, and the circulation of
different serotypes of dengue virus, sometimes all four together, is becoming more
common. Epidemic cycles in some cases are due to the introduction of a new serotype or
the re-emergence of the same serotype after an interval of several years of low or no
transmission. Imported cases are triggering repeated outbreaks in areas where the disease
is not endemic Current estimates indicate that dengue is the most important human
arboviral disease, with between 2.5 and 3.0 billion people (40% of the world's population)
at risk of infection. Every year dengue virus infects 50-100 million people. In 250,000
to 500,000 people, the infection will progress to the severe form of disease, dengue
hemorrhagic fever, and result in 20,000 deaths. In 2004 the United Nations World
Tourism Organization reported that about 125 million international tourists visited
countries where they might be at risk of dengue infection. If, according to Cobelens et al.
(2002), 3% of travellers returning from areas endemic for dengue develop symptomatic
See Annex 1
dengue infection, travel to dengue endemic countries could contribute an additional 3.6
million cases to the global burden of disease.
The textbook description of dengue as a disease of childhood no longer holds true.
Surveillance data presented from multiple countries indicate the highest incidence rates
are among persons 15–24 years of age. Despite apparently successful vector control
programs in some countries such as Singapore, populations that have not experienced
outbreaks for several years are faced with new epidemics; repeated introductions of virus
and rising numbers of dengue-naï persons set the stage for recurrent epidemic activity.
The vector, mainly Aedes aegypti, is found in many more countries than are actually
reporting dengue infection, leading further spread of dengue infection, especially if
environmental factors such as climate change or the El Niño phenomenon allow
continued expansion of the mosquito’s habitat. Aedes aegypti is a peridomestic mosquito
that preferentially breeds in drinking-water containers, plant pots, and natural plants such
as bromeliads. It is difficult to eliminate because control requires active and ongoing
community participation. In addition, urban sprawl with resultant new development has
created new breeding sites. This adaptable vector can also breed in a variety of other
containers such as used tires, abandoned septic tanks, shipping containers in seaports,
cooling units on high-rise buildings, and other areas where water collects. Because these
containers are in public areas that are not the responsibility of any one resident, they
present a special challenge to successful community-based interventions.
Epidemics result in many tens of thousands of people being admitted to hospital for
treatment every year. Severe forms of dengue fever and unusual presentations of dengue
infections such as encephalitis and hepatitis, that do not meet WHO criteria of dengue
hemorrhagic fever, make diagnosis difficult. There is no cure, and treatment is limited to
fluid management and supportive care. Admission to hospital and good clinical
management has generally resulted in the lowering of the case-fatality rates of dengue
hemorrhagic fever to less than 1% in certain countries. There is, as yet, no vaccine.
Progress in the development of tetravalent dengue vaccines makes it essential to prepare
the ground for vaccine eventual introduction. Adequate surveillance and epidemiologic
data are keys to planning for implementation.
Outbreaks of severe acute respiratory syndrome (SARS) and avian influenza, have
heightened the awareness and importance of surveillance and the need for epidemic
preparedness. The International Health Regulations (2005) adopted by the World Health
Assembly in resolution WHA58.3 specifically mentioned dengue fever in its decision
instrument for the assessment and notification of events that may constitute a public
health emergency of international concern. The WHO Regional Committee for the
Western Pacific has endorsed an Asia Pacific Strategy on Emerging Diseases with its
counterpart for South-East Asia (resolution WPR/RC56/R.4).
Obstacles and weaknesses
Generally, surveillance of dengue is not considered adequate in most countries because of
reporting delays and under-reporting of cases. Several days may pass after the bite of an
infected mosquito and the development of severe symptoms that drive ill patients to seek
medical attention. More days are lost when a report (with or without a blood sample) is
sent from the treating facility to the appropriate public health authority for accessioning
(registering the receipt of the sample and assignment of a case identification number) and
data entry. If the system is laboratory-based, additional time is needed for samples to be
tested, often in batches, for confirmation of dengue and for the results to be returned to
the healthcare provider and tallied by the public health authorities. By then, an epidemic
can be in full expansion or at least transmission may have extended beyond the
immediate neighbourhood of the index case, making targeted vector control activities
ineffective. National and regional case definitions for hemorrhagic fever vary, and
differences make classification of dengue hemorrhagic fever difficult. Surveillance does
not allow prediction of future outbreaks with accuracy and needs to be improved if vector
control activities are to be more effective. Also because significant under-reporting
occurs, surveillance data alone does not adequately define the burden of dengue disease.
Additional studies are needed to demonstrate the importance of dengue fever.
Reporting may be limited to clinically suspected cases, and data entry can introduce
errors. Poor sample quality and lack of convalescent samples can further erode the
quality of surveillance data. Laboratory-based and hospital-based systems yield different
data (and syndromic surveillance provides non-specific information to distinguish dengue
from other febrile illnesses), and data from the private sector are hard to capture.
Traditional methods of paper reporting are slow and rely on active participation of
clinical and laboratory staff. Electronic reporting can increase speed and accuracy but
requires significant investment and improvement in infrastructure, but even websites
have disadvantages, such as difficult accessibility, data security, and confidentiality. The
burden of case reporting often falls on healthcare providers who need to make time
complete the paperwork required for reporting but receive no monetary benefit from the
added work. Willingness to report can be improved by simplifying reporting and by
rapidly returning results to providers even if the testing does not impact patient treatment.
Still, not all healthcare providers know about reporting and continued educational
activities may be needed.
Historically surveillance may have been seen as the systematic collection of data, it is
now more: data for action—in other words the ongoing systematic collection, collation,
analysis and interpretation of data, with dissemination of the resulting information to
those who need to know in order that action may be taken.
All participants agreed to the stated objectives of surveillance: 1) to detect early and,
if possible, to predict epidemics or outbreaks, 2) monitor trends, 3) trigger
preventive or control interventions, and 4)evaluate program performance.
In each country, two important systems are necessary for surveillance: the healthcare
system (the medical establishment that provides clinical care to patients) and public
health authority (the branch of government responsible for protecting the population from
preventable diseases). Clinical data collected within the healthcare system become
surveillance data on reporting to the public health authority; this authority analyzes and
interprets the aggregated data in order to provide the basis for the decision-making
process. Conclusions such as the potential for an outbreak or changes in circulating
serotypes are relayed back to the healthcare system to raise awareness for improved
clinical care and other sectors of the public health authority and policy makers to inform
decisions regarding the allocation of resources and for action such as vector control
activities. These data are then used for the evaluation of prevention activities within that
system creating new data and completing the circle (Figure 1). Surveillance can be
passive, a short-term measure to meet the purpose of detecting outbreaks and identifying
high-risk areas, or active with the long-term goal of collecting comprehensive,
comparable data for national and international use, enabling estimates of national,
regional and global disease burdens to be made, and to guide policy, programmatic
decisions and case management.
Health Care System Public Health Authority
Figure 1. Flow of data in public health surveillance.
Slide by M. Favarov
The core functions of surveillance are
analysis and interpretation
action or response
Guidelines are available for each of these functions. For instance, in the 1990s WHO
headquarters issued recommended surveillance standards for dengue2. Regional
guidelines have been drafted by panels of experts on the basis of the global principles and
are used as the basis for national guidelines3, 4. The guidelines include case definitions
and classifications, although there are minor regional variations (some, for instance,
include leukopenia or hepatomegaly in the definition and not all include a "suspected
case" category). One major difficulty with all current guidelines is that some cases of
dengue fever progress to severe disease requiring hospitalization but do not have all the
required criteria to be classified as dengue hemorrhagic fever. Correct classification of
disease is important because patients with dengue hemorrhagic fever are at greater risk
for dengue shock syndrome than patients with classic dengue fever. Also, from an
economic perspective, cases of dengue hemorrhagic fever are more costly to treat and
may therefore impose a greater economic burden on the healthcare system than correctly
classified classic dengue fever cases. A review of the dengue case classification system
of WHO is under way but revised guidelines may not be available for some time.
Data are reported for surveillance to detect outbreaks in the short term and for
programming, planning, prioritization, and documentation of disease burden (essential for
allocation of resources and evaluation of the benefit of immunization) in the long term. It
is important to distinguish these two purposes because surveillance does not (necessarily)
require laboratory confirmation to be useful for outbreak detection. Indeed delaying
action until after laboratory confirmation would likely slow reporting by 1 to 2 weeks.
On the other hand, identifying circulating serotypes in order to prepare for outbreaks and
determining the disease burden in a country in order to prioritize funding require
Dengue haemorrhagic fever: diagnosis, treatment, prevention and control. 2nd edition. Geneva : World
Health Organization. 1997. Available at: .
http://www.who.int/csr/resources/publications/dengue/Denguepublication/en/index.html Accessed: Jan 20,
Southeast Asian Regional Guidelines on Dengue/DHF Prevention and Control (Regional Publication
29/1999 ) Southeast Asian Regional Office. 1999. Available at :
http://www.searo.who.int/en/Section10/Section332/Section554.htm Accessed: Jan 20, 2009.
Guidelines for Dengue Surveillance and Mosquito Control. 2nd edition. Western Pacific Regional Office.
2003. Available at: http://www.wpro.who.int/publications/pub_9290610689.htm Accessed: Jan 20, 2009.
The typical journey of the data relating to one case illustrates the potential for delay. A
case report is completed (with or without collection of a blood sample) when a patient
feels ill enough to seek medical attention—in general, patients seek medical attention 2–4
days after the onset of illness. In the case of dengue hemorrhagic fever the interval is
even longer because the more severe symptoms follow the febrile phase of illness which
can last 5–7 days and which occurs seven days after the bite of an infected mosquito.
The case report is then sent to the public health authority (arriving sometimes hours to
days later); the report is accessioned; the patient information is next entered into a
database, checked and verified: All this often taking several days to a week. Data are
transmitted up the system, from local to central level where they are collated and
analyzed. Even with computer programs that automatically analyze the data, the analysis
and generation of a report on the aggregate data take several additional days. The report
must then be reviewed and interpreted, especially if it suggests that an outbreak may be
occurring. Because key health officials should agree with the results of the analysis
before an outbreak is announced; this type of feedback may require several additional
days. Concerns are often raised about the economic impact of an announcement of an
outbreak, especially in countries in which tourism may be affected—therefore certainty is
The frequency of reporting aggregate data varies, and the means of reporting (and
feedback) used in the different countries ranges from paper to hand-held computers and
internet-based systems. A case study from Nicaragua showed that electronic
enhancements, although not without their problems and needing a significant investment
in infrastructure, do reduce the time for reporting. Inclusion of blood samples as part of
surveillance provides more accurate data but has the potential to delay reporting, because
additional time is required for accessioning, processing and testing of blood samples.
Not testing samples every day, or batch testing, in order to reduce cost and improve
efficiency, results in additional delays. Individual test results must be reviewed and
signed by the laboratory supervisor. Once approved, the various test results for a case are
entered and combined with epidemiological data, again introducing further delays.
Advantages of laboratory-based surveillances include more accurate estimates of dengue
disease burden, improved planning through tracking of the cycling of dengue serotypes,
and provision of feedback to healthcare providers allowing them to improve their clinical
acumen through confirmation of their diagnosis. Because reporting healthcare providers
are the keystone of reporting, giving them feedback is important and offering free testing
can be sufficient inducement.
The range of parties with an interest in dengue surveillance and its results extend from
the patients and their families through to inclusion of senior policy-makers, academics
and legislators. Many and various, these stakeholders have different roles and needs that
have implications for the type and extent of information, and the extent of analysis and
interpretation of data. Patients and parents of sick children may need explanations for
illness, and their contact with the health system increases opportunities for health
promotion and reduction of risk. Others stakeholders include healthcare providers and
other healthcare workers, staff in laboratories, public health and vector control authorities,
health educators, the general public (including travellers), the media, and organizations
such as health insurance bodies, pharmaceutical companies, and international
organizations. Some participants in the Colombo meeting reported differences in the
kinds of stakeholders and the level of participation. Other participants indicated certain
groups should be included that were not generally participating, such as private
practitioners. Nongovernmental organizations seem to play a less significant role than
expected when compared with the extent of their involvement in healthcare delivery.
Issues for stakeholders included the extra work entailed in reporting for healthcare
workers with no monetary benefit and the fact that continuing training and education
maintains interest and may facilitate reporting. A clear message from several countries
was that for many stakeholders, whether public health or vector control authorities,
dengue is just one health problem among many. Furthermore, the privatization of
services and care often has the effect of weakening reporting and surveillance.
Data were collected from the participants by questionnaire and from the presentations on
several specific aspects of surveillance, ranging from whether reporting dengue was
required and the nature of the reporting to the use of case definitions, the means by which
reports were submitted, and the nature of feedback systems (Table 1).
Table 1. Country experiences
Do cases of dengue and dengue All 11 countries responded that both dengue and
haemorrhagic fever and associated dengue haemorrhagic fever and related deaths have to
deaths have to be reported? be reported.
Laboratory confirmed or clinically Nine countries indicated that clinically reported cases
suspected cases are monitored and eventually a fraction or all are
confirmed by laboratory testing. Two reported that
only clinically suspected cases were reported.
Which cases are reported? Patients admitted to hospital: 10/10 (10 of 10
Specific age groups: 7/8 (one country specifies under-
and over-15 years and another reports only pediatric
Patients in the private sector: 6/10 with a seventh
country reporting a few such instances.
Which case definition is used? Four countries reported using the WHO case definition
with a further three reporting that they used an adapted
or slightly modified version; one country reported its
use in some states. Two used other case definitions
(not specifically SEARO or WPRO).
Table 1 Cont.
How frequent is reporting? Immediate: 5/10, including one daily.
Medium of reporting? Paper: 9/11.
Web-based applications: 4/10.
Most important stakeholders? Ministry of health and state health system, policy-
- in theory makers, epidemiologists, healthcare providers, general
practitioners, vector control staff, local health staff, the
community, nongovernmental organizations, social
Most important stakeholders? Ministry of health and local healthcare providers
- in practice including pediatricians and private practitioners,
technical and laboratory workers (at provincial and
district levels), surveillance units, the community,
vector control staff, and the media.
Are there feedback systems? Yes: 10/11; "yes and no": 1/10.
Feedback to whom? State health system and senior ministry officials, local
health authorities, state and district dengue control
teams/program managers, medical services, provincial
supervisors, vector control authorities, and the public.
Rapidity and frequency of Rapidity: within days, a week, after 1 week and after 2
feedback? weeks, "periodically", "as soon as possible", and free
access through web site.
Frequency: daily, weekly (6/10) including weekly web
site updates, monthly.
In all 11 countries, dengue fever and dengue hemorrhagic fever and associated deaths
have to be reported, and in all the countries data are submitted to a central dengue unit (or
an arbovirus unit in one case) in the ministry of health. Most countries monitor and
report clinically suspected cases on a daily or weekly basis. Comparison of the total
number of these cases with historical data is a common method of outbreak detection. In
most but not all, clinically suspected cases are later confirmed through laboratory testing.
Most countries (9 out of 11) are using the WHO case definition or a national version
closely modelled on it. Reporting of laboratory confirmed cases is generally done as soon
as it is available, but four countries indicated this is only possible on a monthly basis.
The medium for reporting is paper or electronic (telephone/fax, email, or web) with
various combinations as appropriate or feasible. All countries report existence of
feedback systems, with one country (Indonesia) having a partial system. Identified
recipients of feedback include national/state and local health authorities, state and district
vector control teams, programme managers, medical services and the general public.
Feedback is on the whole rapid, generally taking a couple of days or a week, and also
generally frequent (weekly or daily during outbreaks of dengue).
A particularly striking example of the effective use of information technology was
reported by Vietnam. All links in the chain from district level to central laboratory and
ministry are linked electronically, and customized software allow the generation of maps
and other reports from the submitted data. The system reduces the workload of
surveillance staff and generates valuable information and feedback. (Although it exists
only in the Vietnamese language, there seems to be no major obstacle to adapting it for
use in other counties aside from the additional funding required to build the infrastructure
where it does not already exist.)
Self-identified positive features of country surveillance systems
Participants were asked to identify the strengths and weaknesses of their systems. Many
of the features identified positively were country specific (see Tables 2, 3, and 4), but
common themes did emerge from both the responses and the presentations. In particular,
it is evident that most countries consider that they have adequate infrastructure and
surveillance systems, and the adjectives "dedicated", committed", "skilled", and
"motivated" are widely used to describe the quality of the personnel engaged in
surveillance. There is evidence of effective links between the various stakeholders;
healthcare providers, laboratory staff, and the public health and vector control authorities.
However, many of these relationships are dependent on personal contacts which are
impacted by staff turnover. The mandatory notification of public health authorities upon
identification of a suspected dengue case is considered valuable. Most countries
indicated training as an essential element in supporting the surveillance system, with
French Polynesia specifically mentioning the regular training of general practitioners
organized by the health ministry.
Advances in information technology are being recognized and taken advantage of
wherever possible. In Kolkata, India, periodic mapping using geographical information
systems helps in localizing cases and outcome assessments. In Singapore the National
Environment Agency is using such systems and the Intranet to create a database of cases
of dengue and Aedes breeding sites.
Several success stories were reported about public education and information, from
diverse settings such as Queensland, Australia; India; Malaysia (with dengue-free schools,
for instance); and Sri Lanka. Awareness is rising, especially following campaigns in
A further strength highlighted is the sense of regional interdependence together with the
international context of World Health Assembly resolutions on epidemic preparedness
and the adoption of the International Health Regulations (2005) and the existence of
agreed case definitions.
Views varied on the value of legislation to enforce vector control. For example, in
Singapore, sanctions include fines for having mosquito breeding sites in homes and stop
work orders on construction sites where mosquitoes are found to be breeding. Similarly
in Malaysia an updated legislative act enables the authorities to close premises
harbouring disease-bearing insects and allows penalties to be imposed.
Table 2. Positive features: surveillance systems
Cambodia Public health monitoring and planning for action; strong system for
both passive and sentinel surveillance, with good forms; good
French Polynesia Dedicated networks with high competencies and skills, and strong
India Integrated disease surveillance program with sentinel surveillance in
Malaysia Standardized surveillance protocols and reporting of dengue fever
and dengue haemorrhagic fever; national database.
Philippines System enables rapid detection of outbreaks; analyses and reports are
generated from sentinel surveillance.
Singapore Timely reporting.
Sri Lanka Good infrastructure.
Thailand System produces information on trends, epidemiological profiles and
data disaggregated by age and sex.
Vietnam Organization of the health system.
Table 3. Positive features: laboratory systems
Australia Good reference laboratory support.
Cambodia Serological and virological testing at sentinel sites.
French Polynesia Strong laboratory infrastructure, with dedicated networks.
India Good network of laboratories.
Malaysia, Laboratory confirmation of cases.
Table 4. Positive features: interagency links, communication and IT applications
Australia Good links between surveillance and vector control authorities; good
public information and communication with the media.
French Polynesia Dedicated networks.
India Application of geographical information systems software.
Malaysia Good links between surveillance and vector control authorities.
Singapore Good links between healthcare providers, laboratories and public
health authorities and between surveillance and vector control
Sri Lanka Good public information and communication with the media.
Vietnam Good links between healthcare providers, laboratories and public
health authorities and between surveillance and vector control
Participants were asked to identify the strengths and weaknesses of their systems (Tables
5 & 6). A shared observation was that disease control is perceived politically as more
valuable than prevention. Given the comment that the highest decision-makers at all
levels are politicians, prevention continues to be an uphill struggle. Decisions about
financing are also political, and inevitably, inadequate or insufficient human and financial
resources, were commonly identified as a weakness throughout the system, although in
one case (Cambodia) it reported that there were vacant field posts but it is difficult to fill
them. Despite the fact that many countries considered the dedication and skills of their
surveillance personnel as a strength, problems remain; Sri Lanka specifically mentioned
poor staff motivation.
Politicians are also responsible for legislation. Legislation imposing fines on households
with breeding sites can sensitize communities and potentially reduce vector density,
promulgation of such laws has not ensured the absence of disease or prevention of
outbreaks. These outcomes illustrate that dengue prevention requires a multifaceted
A lack of prevention services in the provinces is seen as a further impediment, although
other comments pointed to the poor analysis of data at district level. Limitations of the
diagnostic tests are not always understood. Indonesia and Philippines report limited or no
laboratory confirmation, while Malaysia reported a low rate of confirmation by serology,
with diagnostics being available only at central or provincial levels. In general,
virological surveillance is underemphasized or in some cases, such as Indonesia, lacking.
Other weaknesses include a lack of standardization, for example in case definition,
problems of quality assurance and quality control, and the lack of regional or cross-
border sharing of experience and skills. Irregular entomological surveillance was also
identified as an issue.
Other constraints were the physical ones of distance and remoteness. Countries with
archipelagos and remote island territories, such as Australia, Indonesia, Philippines and
French Polynesia, or simply inaccessible terrains or with poor infrastructure, face the
more intractable problems of transporting samples to reference or testing centers and
communicating results. Communication itself raises issues. An advanced software
application for surveillance in Vietnam is only available at present in Vietnamese. In this
case, translation should not be an insurmountable obstacle but more generally language
issues are overlooked: just as different information is needed at different levels, so some
material will have to be translated into local languages and adapted for different
audiences. In that respect, better links need to be cultivated with media and opinion
formers to raise awareness further and encourage not only prevention but also community
action. Other cultural aspects include the perception that the ownership of more drinking
water containers is a sign of wealth rather than multiplying the number of potential
Table 5. Stated weaknesses: infrastructure
Australia Geographical remoteness.
Cambodia Inadequate or insufficient infrastructure; limited human and financial
resources; unfilled vacancies in the field; lack of electronic networks
or access to them.
French Polynesia Lack of human resources in the public health sector; no cost-
effectiveness analysis has been conducted on the surveillance system.
India Variations in infrastructure at state level.
Sri Lanka Low budgets and poor staff motivation; insufficient laboratory
Table 6. Stated weaknesses: surveillance systems
Australia Limited understanding by healthcare providers of the need to report
clinical suspicions early.
Cambodia Lack of standard operating systems; outbreaks detected too late for
intervention; weak prediction and control of outbreaks.
French Polynesia Unknown specificity and sensitivity and predictive values of the
India Variations in the efficiency of notification, problems with
ascertainment of cause of death.
Indonesia Variations in definitions; lack of virological surveillance; surveillance
Philippines Surveillance does not indicate the burden of disease, provides uneven
data and may produce a misleading picture, and cannot indicate
Malaysia, Case reporting not timely for vector-control operations; some
Singapore healthcare providers do not notify in a timely fashion.
Sri Lanka Inadequate reporting from the private sector; inadequate analysis of
data and district and provincial levels.
Thailand Case reporting too late; data cannot be used as the basis for vector-
Vietnam Inadequate reporting of outpatients, from the private sector and
commune level; clinical data include suspected cases; lack of a case
definition for dengue fever; low rate of testing (10% of cases tested
serologically and 5% by virus isolation).
The size of populations at risk of dengue and thus estimates of disease burden may be
higher than current statistics indicate. Published reports show that 110 countries have
populations that are at risk for dengue, but analysis of published data, official reports, and
country websites as well as consideration of countries contiguous to those where dengue
is present put that figure at 124 countries. Limiting estimates to areas at risk within
countries gives a total population at risk of more than 3.6 billion in 2007, about 55% of
the world's population. An attack rate of between 2% and 5% translates into 70 to 180
million infections a year. More frequent outbreaks and epidemics, with a greater
occurrence of serotypes circulating together exacerbate the deteriorating epidemiological
picture, and the evidence of outbreaks indicates that prevention and control functions
were failing. Migration and movement of populations as well as international tourism
further worsen the situation. For instance, using data from the World Tourism
Organization reported in 2004, we can estimate that more than 125 million international
tourists visited countries where they are at risk of dengue infection, and up to nearly half
of febrile travellers returning from endemic areas have serological evidence of recent
Numerous sources need to be scanned to obtain a more accurate epidemiological picture,
but even so there are countries at risk for which there are no published data even (despite
the fact that the dengue vector Aedes aegypti is known to be circulating in these areas)
and more generally the accuracy of existing data varies widely. A major issue is how to
identify additional areas or countries at risk in the absence of any, or good, data.
Each approach to surveillance—active, sentinel and passive—has its advantages and
disadvantages. These need to be identified in order to be able to apply the most
appropriate depending on the context. Although the basic components of good
surveillance systems are known, they are not always available or applied. The lack of, or
failings in, the following can fatally undermine surveillance: networks and motivation of
staff; a clear case definition, and reporting mechanism; an efficient communication
system; basic but sound epidemiology; laboratory support, and good feedback and rapid
response. The private sector needs to be better involved, and in many countries only
cases admitted to hospital are reported.
Healthcare providers should report suspected cases of dengue as soon as possible for
appropriate prevention and control measures to be taken, but in particular there is a need
to improve diagnosis for clinically suspected cases. Currently there is no shortage of
tests for diagnosis of dengue but the most accurate methods require significant expertise
which can only be maintained through high volume and hence centralized testing in
experienced laboratories. The time required for sample transport processing and
distribution of results reduces the clinical utility of these tests because the results are
generally not available for a week or more after the patient consultation that generated the
report. As a result, all dengue patients are diagnosed clinically and treated empirically.
Rapid testing kits are available but are expensive and their reliability varies. Moreover,
healthcare providers not accustomed to the peculiarities of antibody-based diagnostics
might have difficulties in interpreting the results of such tests. Even when excellent
testing facilities are available, accurate diagnosis depends on blood specimens being of
good quality. Sample integrity is challenged when samples are not delivered and tested
in a timely manner. Similarly, patient participation is important because negative dengue
test results on samples collected within the first five days of illness require a second
specimen to be collected a week later in order to rule out dengue with certainty. Rarely
do patients return to provide such samples because their symptoms often have resolved.
The main issues are access to adequate facilities and tests, the availability of good
samples (both single and paired) and their submission in a timely and appropriate way.
Some of the barriers are intractable; there are no technological fixes to overcoming the
difficulties of transporting samples between archipelagos, from remote terrains or over
long distances in order to have rapid delivery. Cold chains need to be maintained to
preserve sample integrity, and results need to be communicated back to the source with
At the political level, one issue related to the effectiveness of legislation against
contravention of vector-control or disease-control laws. Arguments were cited both for
and against, and the jury still seems to be out on the question. For the formulation,
implementation and evaluation of public health policy, data may be available but not
Other issues concerned infrastructure and administration. How can different but parallel
systems—the healthcare system and the public health authority system—be integrated or
how can coordination between the two be increased? How can such improvements be
made at federal, state, provincial and district levels? What steps can be taken to bring
laboratory and clinical services closer together; and public health and vector control
authorities; and the public and private sectors? How can international and cross-border
sharing of experience and other means of cooperation be usefully expanded? What
measures can be taken to recruit staff of high quality and then to motivate and retain such
highly skilled workers?
With regard to information technology, it was observed that some existing websites and
networks appear not to be maintained and are out-of-date or are failing to attract the users
at whom they are aimed. Others are, for obvious reasons, directed solely at national
audiences or linguistic groups. Another issue is language itself; should the national or
local language be used and which level of language? How are such linguistic barriers
Although some users did not yet have access to the Internet or relied on paperwork for
capture of data and reporting, information technology (both hardware and software)
continues to advance. Indeed, these advances are finding applications in some countries
or areas, for example geographical information systems in Kolkata (India) and hand-held
devises and the Internet in Singapore. The question then becomes how can these
advances be applied beneficially and cost-effectively in resource-limited environments?
Recommended best practices
In order to facilitate constructive proposals for next steps and the way ahead, participants
in the meeting agreed on recommended best practices on laboratory practices, data
gathering, reporting and analysis and feedback.
The main stakeholders in the area of laboratory practices are healthcare providers,
laboratory workers, public health authorities, epidemiologists, virologists, vaccinologists,
and policy makers. The critical element to successful laboratory diagnosis of an acute
dengue infection is the timely collection of high quality samples.
1. Reference laboratories at all levels
For virological testing reverse transcription-PCR (RT-PCR) and virus isolation
are the two recommended methods, but detection of the non-structural protein
antigen NS1 may be useful, if further evaluation proves its worth.
For serologic testing both in-house and commercial tests for IgM and IgG
antibodies are recommended. The hemagglutination-inhibition assay remains the
gold standard of serological assays and should be maintained in those laboratories
capable of performing it. Improved versions of the plaque-reduction neutralization
test and newer assays such as focus reduction neutralization test may have a
useful role in evaluation in vaccine trials.
Other laboratories should use assays appropriate to the facilities available, but
should at least use enzyme-linked immunosorbent assays for IgM and IgG.
2. Testing schedules
In the first four days after onset of fever, either RT-PCR or virus isolation are the
recommended assays for confirmation of dengue infection. IgM antibody
detection is an acceptable alternative, specifically if virus detection or isolation is
negative. Nonetheless, a single IgM positive test from an acute sample does not
confirm a current dengue infection, because a positive test obtained this early in
the illness may be from a recent but separate earlier dengue infection. The NS1
antigen assay may prove valuable in the early identification of dengue infections,
but the assay requires further evaluation.
At fever day 5 or later, serology is the method of choice. Although virus
detection is possible through the seventh day after onset of illness, the yield is low.
Therefore, the IgM-capture ELISA should be performed on both acute and
convalescent samples (collected sometime during days 0–4 of illness and days 10–21
of illness, respectively) to demonstrate seroconversion. Paired blood samples are
necessary for definitive serological diagnosis in all cases due to the possibility
that a single acute IgM positive sample may be a result of an earlier dengue
infection. Where possible, IgG antibody detection should also be performed,
particularly on suspected secondary dengue infections due to undetectable IgM
antibody in a percentage of those cases.
Laboratories should be networked, nationally and internationally
Information on virus isolates and gene sequences should be shared; data
(including time and place of isolation, serotype, and case-fatality rate) should be
properly registered in gene data banks
Laboratory staff should receive training, both nationally and internationally
Methods and protocols should be standardized
Laboratories should be upgraded, with training and sharing or sourcing of
The importance of seroprevalence data for vaccine trials should be recognized.
4. Quality assurance and control
Support should be provided for quality control, proficiency testing and good
laboratory practice, and experience should be shared.
Quality assurance and control and proficiency testing should be undertaken at all
levels of laboratory and both within and between laboratories.
Every assay should include standards (i.e. positive, negative and cut-offs).
Laboratories that are unable to conduct basic laboratory surveillance must be brought up
to the minimum standard that will enable them to usefully participate in networks.
Surveillance, data gathering and reporting
Passive surveillance. Although passive surveillance systems are not sensitive and have
low specificity, they are a cost effective means of dengue outbreak detection when
adequate historical data is available for comparison. They are also able to provide
policy-makers with crucial information. The following specific recommendations were
WHO's regional case definitions should be used for suspected, probable and
confirmed cases of all forms of dengue fever
Laboratory confirmation of suspected cases should be sought
In outbreaks, data collection and analysis should be completed as rapidly as
Every country endemic for dengue should have a dengue surveillance system, and
each system should have a quality assurance mechanism
All suspected cases must be reported to a central dengue unit in the health
Legislation should make dengue and dengue hemorrhagic fever a notifiable
disease in every affected country
To understand the burden of disease, periodic additional studies (e.g. capture recapture)
should be conducted and incorporated into the system when possible. This will also
determine the representativeness of the surveillance data. Reporting should be
encouraged from all levels of healthcare facilities in both the public and the private
sectors. In particular, mechanisms to involve the private sector should be developed in
each affected country; one possible way could be to motivate healthcare providers
through the provision of diagnostic feedback.
Reporting should be improved to include cases seen in outpatient departments, without
any loss in quality of data collected. Staff in outpatient clinics may need further training.
Active, sentinel surveillance. The use of sentinel sites for surveillance is appropriate
where resources are limited and surveillance cannot cover all healthcare facilities.
Selection criteria for sentinel sites are usually based on the type of information needed
and the capacity of the facility to collect such information. Specific recommendations are:
Site for surveillances should be selected strategically to achieve a representative
sample of the population at large
Sentinel surveillance should be undertaken by health ministries rather than
universities or other bodies, and should use standardized definitions and
The general principle is weekly reporting to a central unit. Out of epidemic
seasons, reporting may be done once every two weeks or less frequently, but in
the lead-up to the period of expected outbreaks reporting should be at least
weekly. During an outbreak, more frequent reporting, even on a daily basis, may
be useful but reporting will be affected by operating hours of reporting facilities
(e.g. facilities closed on weekend or holidays artificially reduce reported cases
and create surveillance artifacts). Such reports should reach preventive health
units within 48 hours.
In principle, data on all age groups should be reported, especially given the
observation of cases in adult populations. Specifically, it is recommended that the
usual categories in reporting in health information systems should be used,
namely less than 1 year, 1–4 years, 5–14 years and older than 15 years. However,
reporting the median age of cases across all ages is also important to track.
Electronic reporting systems should be developed and used broadly. Such
applications will facilitate formal reporting among countries in the Asia-Pacific
Analysis and feedback
The following objectives of surveillance were defined in terms of indicators needed for
Estimate accurately the incidence of dengue to help estimate the global burden of
the disease, by means of
(a) annual incidence rate
(b) analysis of the representativeness of serum samples collected for
laboratory confirmed dengue cases
Determine the incidence of severe cases through measurement of incidence rates
of dengue fever, dengue haemorrhagic fever and dengue shock syndrome,
hospitalization rates and mortality rates broken down by age group
Detect and forecast dengue outbreaks through determination of
(a) the national threshold for outbreak alert and response
(b) identification and application of factors that predict outbreaks
Monitor the seasonality, age distribution and transmission patterns, and evaluate
and guide the introduction of a potential vaccine, in terms of
(a) weekly incidence of dengue, with data broken down by age, gender
and location to allow effective use of vector control resources
(b) analysis of the representativeness of serum samples collected for
laboratory confirmed dengue cases
(c) annual distribution of serotypes and sequential analyses
(d) molecular characterization of a sample of isolated viruses
Monitor intervention programs
(a) starting with baseline data, and analysis of the patterns of the vector
population (species, density, and vector-control indices)
(b) in terms of the impact of interventions (with disease reduction as a
measure of impact, and house index, container index and Breteau
index as indicators of outcome)
Table 7 shows the recommended flow and frequency of feedback to key participants in
the surveillance system.
Table 7. Feedback
To whom How How often
Public and media Website with possibility of Weekly updates
reporting rumors and replies
Healthcare providers Website and newsletters Weekly
Policy-makers Surveillance report Annual
International organizations Surveillance report Annual
Pharmaceutical companies Website and newsletters Weekly
Public health authorities Website with secured pages Weekly updates
for detailed information by
In addition, mechanisms should be devised for the sharing of data among countries.
ASIA-PACIFIC DENGUE PREVENTION BOARD
June 21-23, 2007
Colombo, Sri Lanka
DAY 1: Thursday, June 21, 2007
TIME AGENDA ITEM Presenters
8:30 - 9:00 am Welcome H.A.P. Kahandaliyanage
Introductory remarks Secretary, Min of Health
Introduction of participants, chairman Care and Nutrition
Objectives, process, expected outcomes A. Amarasinghe (Meeting
9:00 – 10:00 am Surveillance: Definition and Ideal, Goals and M. Favorov
10:00 – 10:30 am Surveillance: WHO guidelines B. Letson
10:30 – 10:45 am Coffee Break
10:45 – 11:15 am Results reporting: Availability & methods of M. Beatty
presentation, distribution of results
11:15 – 11:45 am Surveillance in context: Key issues for M. Beatty
11:45 - 1:00 pm Lunch
1:00 – 1:30 pm Dengue Surveillance in Travelers T. Takasaki
1:30 - 2:15 pm Vector surveillance and control: Singapore Goh Kee Tai
2:15 - 2:30 pm Coffee Break
2:30 - 3: 00 pm Vector surveillance and control: Malaysia L. H. Lim
3:00 – 3:30 pm Country presentations: Philippines E. Lopez
3:30 - 4:00 pm Country presentations: Sri Lanka N. Abeysinghe
4:00 - 5:00 pm Moderated Discussion: B. Letson
7:00 – 8:00 pm Dinner: All participant in Asia-Pacific Dengue
Prevention Board meeting
DAY 2: Friday, June 22, 2007
TIME AGENDA ITEM Presenters
8:00 – 8:30 am Viet Nam L. C. Quang
8:30 – 9:00 am French Polynesia R. Teyssou
9:00 - 9:30 am Cambodia: MOH R. Huy
9:30 - 10:00 am Cambodia: Capture-recapture in dengue surveillance S. Vong
10:00 - 10:30 am Australia A. Richards
10:30 – 10:45 am Coffee Break
10:45 – 11:15 am Thailand W. Hanshaoworakul
11:15 – 11: 30am India: National Surveillance N. Wairagkar
11:30 – 12:00 am India: Kolkata District Surveillance T. Sen
12:00 - 1:00 pm Lunch
1:00 - 1:30 pm Issues in Laboratory Diagnostics: Viet Nam V.T.Q. Huong
1:30 - 2:00 pm Country Presentations: India S. Chatterjee
2:00 - 2:30 pm Malaysia S. Devi
2:30 – 3:00 pm Coffee Break
3:00 - 3:30 pm Laboratory Diagnostics: Summary and Best Practices D. Edgil
3:30 - 4:00 pm WPRO Chang Moh Seng
4:00 - 4:30 pm TBN TBN
4:30 - 5:00 pm Global burden of dengue and the need for global M. Beatty
5:00 - 6:00 pm Facilitated Discussion on Dengue Surveillance J. Kuritsky
7:00 – 8:00 pm Dinner on your own
DAY 3: SATURDAY, JUNE 23, 2007
TIME AGENDA ITEM Presenters
9:00 – 11:00 am Summary and Conclusions: Best Practices for D. FitzSimons
Dengue Surveillance J. Kuritsky
11:00 - 11:30 am Coffee Break
11:30 - 12:30 am Board Meeting A. Amarasinghe
Membership R. Mahoney
(topics, locations and dates)
Any other business
12:30 am Closing comments and adjournment
ANNEX 2 Asia-Pacific Dengue Prevention Board
LIST OF PARTICIPANTS
AMARASINGHE, Dr Ananda SINGHASIVANON, Dr Pratap
Epidemiologist Vaccine Trial Center
Epidemiology Unit Faculty of Tropical Medicine
231, De Saram Place Mahidol University
Colombo 10, SRI LANKA 420/6 Rajavithi Road
Tel: 94-11-2695112 Bangkok, 10400, THAILAND
Fax: 94-11-2696583 Tel: 66 2354 9199
E-mail: email@example.com E-Mail: firstname.lastname@example.org
HANNA, Dr Jeffrey SYAHURACHMAN, Dr Agus
Public Health Physician Department of Microbiology
Tropical Population Health Unit Faculty of Medicine
PO Box 1103 Univsity of Indonesia
CAIRNS QLD 4870 JI. Salemba Raya 6, Jakarta Pusat 10430
Tel: 61 (07) 4050 3604 Tel: 62-21-3100806
Fax: 61 (07) 4031 1440 Fax: 62-21-3100810
E-mail: email@example.com E-mail: firstname.lastname@example.org
LAM, Dr Sai Kit TIEN, Dr Nguyen Thi Kim
Emeritus Professor Dato' Dr. Lam Sai Kit, MSc, (Unavailable to attend)
PhD, FRCPath, FRCP, FIDSA, FAAM, FASc, Director
Knight ONM (France) Pasteur Institute of HCMC, Vietnam
President 167 Pasteur Street, District 3
Asia Pacific Society for Medical Virology HCMC, VIETNAM
5 Jalan SS20/23 Tel: 84 8 8 203 313
Damansara Utama Fax: 84 8 8 231 419
47400 Petaling Jaya E-mail: email@example.com
Tel: + 6-017-8800044
Fax: 603-7725 9635
E-mail: firstname.lastname@example.org WAGATSUMA, Dr Yukiko
Professor and Head
VONG, Dr Sirenda Department of Epidemiology
Head, Epidemiology and Public Health Unit Graduate School of Comprehensive
Institut Pasteur du Cambodge Human Sciences
5, Bld Monivong - P.O. Box 983 - University of Tsukuba
Phnom Penh, CAMBODIA 1-1-1 Tennodai, Tsukuba
Tel: 855 12 333 650 Ibaraki 305-8575, JAPAN
Fax: 855 23 725 606 Tel/Fax: 029 853 3489
E-Mail: email@example.com E-mail: firstname.lastname@example.org
CHO, Dr Byung-Ki CUONG, Dr Nugyen Phu
Director of R&D Department TDR Fellow
Standard Diagnostics, Inc. Western Pacific Regional Office
56-68 Hagal-dong, Giheung-gu P. O. Box 2932
Yongin-si, Kyonggi-do, KOREA 449-906 United Nations Ave.
Tel: 82-31-899-9761 Manila, PHILIPPINES
Fax: 82-31-899-9760 Tel: 632 528 9760
E-mail: email@example.com E-mail: firstname.lastname@example.org
HUTAGALUNG, Dr Yanee OGAWA, Tetsuro
Director General Manager
Clinical R&D and Medical Affairs Development & Designing Dept. 1
Greater Mekong New Ceramics Div./ Life Care Business Div.
GlaxoSmithKline Biologicals PENTAX Corporation
Tel: 662 659 3060 2-36-9 Maeno-cho,
Fax: 662 659 3147 Itabashi-ku, Tokyo 174-8639, JAPAN
E-mail: email@example.com Tel:813-3960-1290 / Fax:813-3960-2681
Analyst – Exploratory & Pre-Clinical Portfolio, Dengue PRASITTISUK, Dr Chusak
R&D Commercial Strategy Coordinator,
Global Biologicals Commercial Operations Communicable Disease Control
GlaxoSmithKline Biologicals (CDC/SEARO)
Rue de l'Institut 89 World Health Organization
B-1330 Rixensart, BELGIUM Regional Office for South-East Asia
Tel: 32 (0)2 656 6702/ I.P. Estate, Mahatma Gandhi Road
Fax: 32 (0)2 656 8113 New Delhi - 110 002, INDIA
E-mail: firstname.lastname@example.org Tel: 91 11 23309115
23370804, Ext: 26115
WARTEL, Dr Tram Anh Fax: 91 11 23378412
Clinical Scientist E-mail: email@example.com
Representative of Clinical Development (France)
for the Dengue Project in Asia NG, Timothy MD, MHSc,
Sanofi pasteur Representative Office FRCPC, FRCSC, FACOG
17 Tu Xuong street – District 3 Director, Epidemiology,
Ho Chi Minh city – VIETNAM Clinical R&D and Medical Affairs
Tel: 84 8 9322766 (Ext. 121) Asia Pacific, Australasia, China/Hong
Fax: 84 8 9322769 and Japan
E-mail: firstname.lastname@example.org GlaxoSmithKline Biological
FAVOROV, Dr. Michael O. M.D., Ph.D., D.Sc. WAIRAGKAR, Niteen S., MD
CDC Central Asia Office Director 20 A, Ambedkar Road, Post box 11,
Division of Epidemiology and Pune- 411001, INDIA
Surveillance Capacity Development, 91-20-27657485 (RES)
Coordinating Office of Global Health Email: email@example.com /
Centers for Disease Control and Prevention firstname.lastname@example.org
+7 3272 50 76 12 Ext 450
Tel: 91 20 2612 6302/04 ext 223
PRYOR, Dr. Jan MENDIS, Dr Devika
Professor and Director – Research MO, Dengue Surveillance
Fiji School of Medicine SRI LANKA
Private Mail Bag
Suva, FIJI ISLANDS Weerasinghe, Dr Indira
work: (679)323-3401 Entomologist
FAX: (679)331-1940 SRI LANKA
mobile: (679)992-0792 GUNASENA, Dr Sunethra
email: email@example.com Virologist
gmail: firstname.lastname@example.org SRI LANKA
DEVER, Gregory, MD
ABEYSINGHE , Dr Nihal Ministry of Health, PALAUu
Chief Epidemiologist email@example.com or
Ministry of Health firstname.lastname@example.org or
SRI LANKA email@example.com
Fax: +94-112-696583 de SILVA, Dr Lakshmi
e-mail: firstname.lastname@example.org National Coordinator,
Dengue Control Unit
CHATTERJEE, Shyamalendu, PhD TAI, A/Prof Goh Kee
Scientist Senior Consultant
I.C.M.R Virus Unit, Office of the Director of Medical Services
GB-4, 1st. Fl. Ministry of Health
I.D.& B.G Hospital College of Medicine Building
57, Dr. S.C. Banerjee Road, 16, College Roa d
Beliaghata, Kolkata-713 101 SINGAPORE 169854
West Bengal, INDIA Email: GOH_Kee_Tai@moh.gov.sg
Tel: 91 33 2353 7525
Fax: 91 33 2353 7424
BUTAC, Charity Ann MD HUONG,Vu Thi Que MD, PhD
Liaison Personnel/ In-Country Leader Head, Laboratory of Arboviruses
Philippines-AFRIMS Virology Research Unit Head,
Rm 401, 4th Flr Pag-Ibig Fund/ Depart. of Microbiology-Immunology
WT Corporate Tower Pasteur Institute Ho Chi Minh City
Mindanao Ave., Cebu Business Park 167 Pasteur Street, District 3
Cebu City 6000 PHILLIPINES Ho Chi Minh City, VIETNAM.
Tel/Fax: 63 32 415 9579 Tel: 84 8 8 296 351
Email: email@example.com / Fax: 84 8 8 231 419
firstname.lastname@example.org E-mail: email@example.com
QUANG, Luong Chan, MD, MSc TEYSSOU, Dr Remy
Researcher Assoc. Director,
Department of Public Health Research Institute Louis Malarde
Pasteur Institute in HoChiMinh City BP30
167, Pasteur Street, District 3, HoChiMinh City, VIETNAM 98713 Papeete
Tel: 84 8 824 3334 POLUNESIE FRANCAISE
Fax: 84 8 823 1419 Tel: 689 416 447 /
Email: firstname.lastname@example.org Fax: + 689 431 590
RICHARDS, Ms Ann SEN , Tapas Kumar
Public Health Officer in the Tropical Population Health Unit Kolkata, INDIA
Queensland, AUSTRALIA email@example.com
KURANE, Ichiro DEVI, Shamala
LIM, Lee Han UNGCHUSAK, Kumnuan
MARGOLIS, Dr Harold S. KURITSKY, Dr Joel
Director, PDVI Deputy Director, PDVI
International Vaccine Institute International Vaccine Institute
SNU Research Park, SNU Research Park,
San 4-8 Bongcheon-7dong San 4-8 Bongcheon-7dong
Kwanak-gu, Seoul, KOREA 151-818 Kwanak-gu, Seoul, KOREA 151-818
Tel: 82 2 881 1256 Tel: 82 2 881 1213
Fax: 82 2 881 1215 Fax: 82 2 881 1215
E-mail: firstname.lastname@example.org E-mail: email@example.com
MAHONEY, Dr Richard LETSON, Dr Bill, MD
Director, Vaccine Access Director, Vaccine Evaluation, PDVI
Pediatric Dengue Vaccine Initiative Pediatric Dengue Vaccine Initiative
International Vaccine Institute International Vaccine Institute
Tel: 1 928 282 1608 Tel: 822 881 1262
Fax: 1 928 222 0074 Fax: 822 881 1215
E-mail: firstname.lastname@example.org Email: email@example.com
BEATTY, Dr Mark E. , MD, MPH EDGIL, Dianna M. , PhD
Medical Epidemiologist (Scientist), Scientist, Infectious Diseases
Pediatric Dengue Vaccine Initiative Pediatric Dengue Vaccine Initiative
International Vaccine Institute International Vaccine Institute
Tel: 822 881 1277 Tel: 822 881 1270
Fax: 822 881 1215 Fax: 822 881 1215
Email: firstname.lastname@example.org Email: email@example.com
KIM, Nam Hee
Administrative Assistant, PDVI
International Vaccine Institute
SNU Research Park, San 4-8 Bongcheon-7dong
Kwanak-gu, Seoul, KOREA 151-818
Tel: 82 2 881 1124
Fax: 82 2 881 1215
David W. FITZSIMONS
Dengue and dengue hemorrhagic fever in the Americas, PAHO 1995
Chapter 2 Dengue and dengue hemorrhagic fever
Chapter 3 Surveillance
Best Practices for Dengue prevention and control in the America, Environmental Health Project,
Chapter 2.2 The 10 Essential elements of a dengue prevention and control program
Chapter 3.2 Weekly epidemiological report
Chapter 3.3 Dengue diagnostic laboratory
Chapter 3.8 Clinical case definitions
Dengue Haemorrhagic fever, diagnosis, treatment, and control, WHO 1997
Chapter 5 Vector surveillance and control
Chapter 6 Disease surveillance and outbreak prevention
Protocol for the assessment of National Communicable Disease Surveillance and Response
WHO Recommended surveillance standards, WHO
Page 8-14 National coordination of communicable disease surveillance
Page 39-40 Dengue Fever
Page 129-30 Acute haemorrhagic fever syndromes
Annex 3 Role and use of Geographic Information Systems (GIS) and mapping for
Prevention and control of dengue and dengue haemorrhagic fever, SEARO
Chapter 3 Clinical manifestations and diagnosis
Chapter 5 Laboratory diagnosis
Chapter 6 Epidemiologic surveillance
Chapter 11 The regional strategy for the prevention and control of DF/DHF
Chapter 12 Emergency preparedness and effective response
Dengue fever: Management plan for North Queensland
A blueprint for action for the next generation dengue prevention and control, PAHO, 1999
Framework for evaluating public health surveillance systems for early detection of outbreaks,
US Centers for Disease Control and Prevention, 2004
Guidelines for evaluating surveillance systems, US Centers for Disease Control and Prevention,
Framework for program evaluation in public health, US Centers for Disease Control and
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