Search Strategy – Droplet Precautions

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					                                 Search Strategy – Droplet Precautions

PRINCIPAL RESEARCH QUESTION/OBJECTIVE:

What precautions can be taken to ensure patients/healthcare workers/visitors safety from droplets which are
disseminated during healthcare procedures or human activities?

Search strategy for identification of studies

Key Questions

    1.   What activities (including healthcare procedures and human activities e.g. coughing etc) can cause
         droplets to be disseminated from the respiratory tract?

    2.   What precautions can be taken to ensure patients/healthcare workers/visitors safety from droplets
         which are disseminated during healthcare procedures or human activities?

    3.   What microorganisms are disseminated via droplets from infected/colonised patients with the potential
         to cause cross-transmission and cross-infection in patients/healthcare workers/visitors?

    4.   What type of environment(s) should be used to deliver care to patients with infections that can be
         disseminated via droplets?

The recommendations and “Droplet Precautions – a systematic review of the evidence” are based on a
collation of review and critical appraisal of the scientific evidence identified by search strategies carried out
using the above key questions.

Further details on each search strategy and results can be supplied on request.

Period of publication         January 2008 - April 2009
Strategy key words            Droplet$                                        Disease transmission
(Full search strategies       Precaution$                                     Nebulization
available on request)         Patient$                                        Exp Respiratory tract infections/
                              Healthcare worker$                              Exp Disease reservoirs/
                              Visitor$                                        Sneezing
                              Healthcare                                      Speaking
                              Personal protective equipment                   Intubation
                              Patient placement                               Nasopharyngeal aspiration
                              Isolation                                       Respiratory tract infection$
                              Environment$                                    Nebulisation
                              Exp Patients’ rooms/                            Infection
                              Care                                            Coughing
                              Exp “Delivery of healthcare”/                   Droplet transmission
                              Exp infection/                                  Exp Disease Transmission, Infectious/
                              Cross infection                                 Exp Cross Infection
                              Nosocomial                                      Healthcare associated infection
                              Healthcare-associated infection                 Healthcare acquired infection
                              Hospital acquired infection                     Hospital
                              Exp Hospitals/                                  Occupational transmission
                              Infective material                              Infective agent
                              Infective pathogen                              Infective microorganism
                              Exp cough/                                      Cough
                              Exp sneezing/                                   Exp "nebulizers and vaporizers"/
                              Exp intubation                                  Exp intubation, intratracheal/
                              Exp Gloves, Surgical/                           Exp Gloves, Protective/
                              Gloves                                          Exp Protective Clothing/
                              Gown$                                           Mask
                              Exp Masks/                                      FFP3
Droplet Precautions: Literature Review                                                                         April 2009
                                                       Page 1 of 16
                          N95                                        Exp Eye Protective Devices/
                          Eye protection                             Exp Protective Clothing/
                          Exp Protective Devices/                    Exp Health Facility Environment/
                          Exp Patients/                              Exp Personnel, Hospital/
                          Exp Health Personnel/                      Healthcare personnel
                          Exp Visitors to Patients/                  Single room
                          Cohorting                                  Handwashing
                          Exp Handwashing/                           Hand hygiene
                          Patient environment                        Patient transport
                          Infection control                          Exp Infection Control/
                          Exp Patient Isolation/                     Isolation
                          Bacterial Infections/                      Infectious Disease Transmission, Patient-to-
                                                                     Professional/
                          Infectious Disease Transmission,           Adenovirus
                          Professional-to-Patient/
                          Bronchiolitis                              Exp Bronchiolitis/
                          Exp Diphtheria/                            Diphtheria
                          Epiglottitis                               Exp Epiglottitis/
                          Influenza                                  Exp Influenza, Human/
                          Pandemic influenza                         Meningitis
                          Exp Meningitis, Meningococcal/             Mumps
                          Exp Mumps/                                 Methicillin resistant staphylococcus aureus
                          Exp Methicillin-Resistant Staphylococcus   Exp Pneumonia, Mycoplasma/
                          aureus/
                          Exp Mycoplasma pneumoniae/                 Mycoplasma
                          Parvovirus B19, Human/                     Parvovirus B19
                          Slapped cheek syndrome                     Yersinia pestis
                          Exp Yersinia pestis/                       Exp Rubella/
                          Rubella                                    German measles
                          Respiratory syncytial virus                Exp Respiratory Syncytial Viruses/
                          Rotavirus                                  Exp Rotavirus/
                          Severe acute respiratory syndrome          Exp Severe Acute Respiratory Syndrome/
                          Group A streptococcus                      Whooping cough
                          Exp Whooping Cough/                        Bordetella pertussis
                          Exp Bordetella pertussis/                  Exp Hemorrhagic Fevers, Viral/
                          Viral haemorrhagic fever                   Exp Health Facility Environment/




Droplet Precautions: Literature Review                                                                  April 2009
                                                      Page 2 of 16
Electronic databases           MEDLINE                                     X   PsycINFO
(tick as appropriate)          Science Direct                                  EMBASE
                               CINAHL                                      X   SIGLE
                               Cochrane Library                            X   Web of Science
                               British Nursing Index                       X


Additional Resources               References checked for relevant articles                                   X
(tick as appropriate)              Review of abstracts of professional meetings/ conferences
                                   Personal libraries consulted
                                   Experts consulted (give details if applicable)
                                   Handsearching of journals (name relevant journals e.g. Journal of Hospital Infection,
                                   Infection Control and Hospital Epidemiology)

                                   American Journal of Infection Control
                                   The Lancet Infectious Diseases
                                   Journal of Hospital Infection
                                   Infection Control & Hospital Epidemiology
                                   Eurosurveillance
                                   MMWR (CDC)
Websites                           CDC                                    X WHO                                            X
(tick as appropriate)              Department of Health                  X Scottish Government                             X
                                   HPA                                    X Scottish Government Health Dept.               X
How many papers found              107
How many papers included           19 (+ 4 guidance documents)
How many papers excluded           88

ii) Selection criteria for inclusion of studies
Sample                               All health and social care workers.

Outcome measure(s)                 Interventions to minimise the spread of infections by droplets.

Other inclusion criteria           N/A


Language Limitations               English language only




Droplet Precautions: Literature Review                                                                           April 2009
                                                         Page 3 of 16
iii) Quality assessment
Study quality assessment

Initial review

The CDC Guideline for Isolation Precautions: Preventing Transmission of Infectious Agents in Healthcare Settings 2007,
(Siegel et al., 2007) has been evaluated by five independent reviewers using the AGREE instrument (The AGREE
Collaboration, 2001) which is designed to assess the methodological quality of guidelines. The results show the guidelines
suitable for adaptation as the primary reference source for literature review and formulation of recommendations.

A literature search was conducted using HPS Infection Control Team (ICT) search strategies, based on agreed research
questions. Identified studies, not already reviewed within the CDC guidelines, were assessed for relevance and critically
appraised using SIGN-50 methodology (SIGN, 2004) to determine if additional information or considerations were required
for production of transmission based precautions for healthcare settings in NHS Scotland.

The methodology for grading the supporting evidence is found on the Evidence Tables including Considered Judgment
Section and available from the HPS Infection Control Team on request.

Current update

A literature search was conducted using HPS ICT search strategies, based on the agreed research questions. Identified studies
were assessed for relevance and critically appraised using SIGN-50 methodology (SIGN, 2004) to determine if additional
information or considerations were required for updating of the existing transmission based precautions for healthcare
settings in NHS Scotland.

The methodology for grading the supporting evidence is found on the Evidence Tables including Considered Judgment
Section and available from the HPS Infection Control Team on request.

Category of Recommendation
The recommendations have been categorised based on a combination of the system used in the CDC/HICPAC (Siegel et al.,
2007) and EPIC 2 National Evidence-Based Guidelines for Preventing Healthcare-Associated Infections in NHS Hospitals in
England

Category IA - Strongly recommended for implementation and strongly supported by well-designed experimental, clinical, or
epidemiologic studies.
Category IB - Strongly recommended for implementation and supported by some experimental, clinical, or epidemiologic
studies and a strong theoretical rationale.
Category IC - Mandatory or required for implementation
Category II - Suggested for implementation and supported by suggestive clinical or epidemiologic studies or a theoretical
rationale.
GPP (Good Practice Point) – Is a recommendation for best practice based on the expert opinion or practical experience of
the Model Policies Steering Group
No recommendation; unresolved issue. Practices for which insufficient evidence or no consensus regarding efficacy exists.




Data collation and analysis

The SIGN 50 methodology including reviewing templates are available from the SIGN website (http://www.sign.ac.uk)

The AGREE Instrument which is used for assessment and evaluation of the quality of evidence-based guidelines can be found
at www.agreecollaboration.org




Droplet Precautions: Literature Review                                                                          April 2009
                                                      Page 4 of 16
                        1    Recommendations – Droplet Precautions
This review aims to identify, review and critique any scientific studies or guidance, which have been
published in the intervening period since the last update (2008), to determine if changes to guidance
are required.

Caveat

Transmission based precautions are designed to be an adjunct to standard infection control
precautions. It is therefore stressed that the nine elements of standard infection control precautions
must underpin all health and social care activities. It is therefore assumed for the purpose of this
literature review that all standard infection control precautions are being adhered to and therefore do
not require to be specifically addressed within this literature review and associated recommendations.

More information on the standard infection control precautions including associated literature reviews
is available from the Model Infection Control Policies website:
http://www.hps.scot.nhs.uk/haiic/ic/modelinfectioncontrolpolicies.aspx

A full description of the criteria used to determine if additional precautions are required is included in
Appendix 1 of the transmission based precautions policies.


1.1   It is recommended that the National Colour Coding for Hospital Cleaning Materials and
      Equipment be incorporated into the model policy.


                                     2    Practical Application
As the use of droplet precautions has been recommended for some time, no significant change to
practice should be required, however, the standards set down must be achieved.


                                     3   Resource Implications
As per current policies. All resources required for implementing droplet precautions should already be
in place.




Droplet Precautions: Literature Review                                                           April 2009
                                               Page 5 of 16
            4     Droplet Precautions – A Systematic Review of The Evidence
This review aims to identify, review and critique any scientific studies or guidance, which have been
published in the intervening period since the last update (2008), to determine if changes to guidance
are required.

Caveat

Transmission based precautions are designed to be an adjunct to standard infection control
precautions. It is therefore stressed that the nine elements of standard infection control precautions
must underpin all health and social care activities. It is therefore assumed for the purpose of this
literature review that all standard infection control precautions are being adhered to and therefore do
not require to be specifically addressed within this literature review and associated recommendations.

More information on the standard infection control precautions including associated literature reviews
is available from the Model Infection Control Policies website:
http://www.hps.scot.nhs.uk/haiic/ic/modelinfectioncontrolpolicies.aspx

4.1   Transmission Based Precautions

A general review has been published highlighting non-pharmacological interventions for the
prevention of HAIs (Curtis, 2008). Although the measures listed in the paper mostly relate to contact
precautions, as this is the most common mode of transmission for the majority of HAIs such as MRSA
and C. difficile, the overall message given is that a combination of precautions is better than using an
individual precaution and this can be applied to any transmission based prevention strategy.

It is of interest to note that the infection control precautions produced by Siegel et al (Siegel et al.,
2007), the basis of the HPS Infection Control Transmission Based Precautions Policies, are also the
recommended infection control precautions in the SHEA/APIC Guideline For The Prevention And
Control of Infection in Long Term Care Facilities published in July of 2008 (Smith et al., 2008).

In August 2008 Health Facilities Scotland completed the implementation of the National Colour
Coding for Hospital Cleaning Materials and Equipment (HFS, 2008). This system ensures that
cleaning items cannot be used in multiple areas, reducing the potential for cross contamination to
occur. It is based on the National Patient Safety Agency’s colour coding system released in England
and Wales (NPSA, 2007) and specifies that cleaning items such as cloths, buckets, aprons etc should
be yellow for isolation areas.

4.2   Influenza

From the results of the literature search a number of papers were found in relation to the influenza
virus. A recent review on influenza A virus has stated that there is still debate regarding the potential
route of transmission (Weber and Stilianakis, 2008). From the literature reviewed by the authors they
conclude that there may be too much focus on the transmission of this virus via large droplets and that
the transmission of it via an airborne route may be likely, particularly within indoor environments with
no ventilation. However although the authors reach this conclusion they do not give any
recommendation in this regard and conclude that further study is required.

A rapid communication has been released in Eurosurveillance regarding the public health implications
of Influenza B outbreaks in the UK for 2007/08 within closed settings such as care homes (Mook et
al., 2008). It is interesting to note that no outbreaks were reported in Scotland with the majority being
reported in England and most outbreaks occurred in care homes where vaccine coverage was >70%. It
Droplet Precautions: Literature Review                                                            April 2009
                                                Page 6 of 16
was later discovered that the virus combination used for that season’s vaccine did not provide
coverage for the strain which was presenting within these community settings. This therefore
highlights the importance of not relying on vaccine alone when controlling outbreaks and that strict
enforcement of infection control measures are vital to prevent spread. A case control study looking at
the clinical features of influenza has also stated that rapid testing and isolation precautions are vital to
slowing the spread of the virus (Babcock et al., 2008).

This combined approach of adequate vaccine coverage and implementation of effective control
measures is detailed in the management of an influenza outbreak in a locked behavioral health unit
(Risa et al., 2009) where approximately half of the residents were immunised. As this is a challenging
environment to enforce infection control precautions a number of appropriate measures were used
such as closing the unit to new admissions and visitors, re-educating staff and patients in the correct
procedures for hand hygiene and cough etiquette as well as offering both chemoprophylaxis for those
with symptoms and immunisation to those not already ill or vaccinated.

A paper looking at the effectiveness of 3 alcohol based hand rubs against the influenza virus strain
H1N1 has been recently published (Grayson et al., 2009). The study used twenty vaccinated volunteers
and each was tested with the five hand hygiene protocols (no hand hygiene; water and liquid soap;
three alcohol based hand rubs each containing an alcohol concentration of 60% - 70%). From the
results of this small scale study it was found that all hand hygiene protocols, including the control,
caused some reduction from the initial inoculum. Another interesting finding from this study is that
some of the volunteers had no culture detected virus even at the initial baseline reading. The authors
therefore concluded that some people’s skin environment may cause inactivation of the virus strain
tested. When the results of the soap and water and alcohol based hand rubs were compared it was
found that they were comparable to within one to a hundred virus copies. This therefore confirms the
previous recommendations that both these methods of hand hygiene are viable. Additionally the use
of alcohol based hand rub allows for a reduced time to perform hand hygiene and less irritation to the
skin.

4.3   Personal Protective Equipment

The papers found relating to PPE from the literature search mainly assessed the knowledge and
compliance with PPE and especially the use of facial protection. One study evaluated the effectiveness
of an online infection control course for improving the selection and procedure used (Hon et al., 2008).
It is interesting to note from this study that from the three types of precautions (i.e. droplet, contact,
airborne) studied in relation to “transmission specific clinical scenarios”, the greatest improvement
was the compliance to the correct procedures for droplet precautions even although it was identified as
the most complicated procedure of the three. Therefore when considering these results in this
particular study population it could be concluded that the required PPE and procedure for donning and
removing it for droplet precautions is confusing to Healthcare Workers (HCWs) and that the influence
of online training has a positive effect on this. This study however has some potential limitations; it
may not be able to be generalised, and there may have been the influence of the Hawthorne effect.

Another study assessed the HCW’s compliance to the recommended CDC respiratory infection control
guidelines in emergency and primary healthcare environments (Turnberg et al., 2008). As these
settings can be the first point of entry for most patients wishing to receive healthcare for
suspected/confirmed respiratory infections, it is important that the staff in these areas are compliant
with the current recommendations. Although this paper mostly concentrates on the spatial separation
and use of cough etiquette, which will be assessed in a later section of this literature review, it does
contain one finding which is of relevance to this section. From the assessment of the different medical
centres/job types it was found that one quarter or less of the participants in this study considered the
use of eye protection or a mask when attending to patients that are sneezing or coughing. In the

Droplet Precautions: Literature Review                                                             April 2009
                                                Page 7 of 16
discussion they suggest that this lack of compliance could possibly be due to practical restrictions
preventing the achievement of the recommended practices. This study although interesting had a
number of limitations, as it was qualitative questionnaire study (e.g. participants influencing the results
based on their personal opinions, study participant rate etc).

The same limitations expressed about Turnberg et al’s study can also be applied to another undertaken
in 9 units of 2 urban hospitals looking at factors that influence nurses’ compliance to facial protection
(Nichol et al., 2008), however, the methods used to collate and analyze the results of this particular
study allowed specific aspects to be assessed in detail and multivariate analysis to be undertaken. The
authors of the study concluded that five factors were found to influence compliance. These were; full
time work status, greater than 5 years experience as a nurse, a belief that media coverage of infectious
diseases impacts on risk perception and work practices, at least monthly use of facial protection and
organisational support for health and safety. This information should allow management to identify
areas requiring appropriate training.

A study looking at the performance of surgical masks (Oberg and Brosseau, 2008) was highlighted in
the literature search and although it relates to their potential use for droplet nuclei rather than large
droplets the results do strengthen the current recommendations included in the droplet precautions
policy. The authors of this study conducted a number tests (both qualitative and quantitative) on 9
selected surgical masks and concluded that surgical masks should not be used for aerosol generating
infections and that a N95 respirator should be used. One point of significance regarding this study is
that there is a noted improvement in the surgical masks as the particle size was increased. As droplets
are defined as any particle above a size of 5µm (however the results of the study do not reach this
particle size) then the use of surgical masks for these infections is still viable as long as no aerosol
generating procedures are taking place which would reduce the particle size produced.

A Health and Safety Executive report (HSE, 2008) looking at the performance of surgical masks
concluded similar results to that of the previous study. From the findings using both volunteers and
simulated breathing devices, the researchers found that surgical masks if used in the proper manner
can provide ample protection against large droplets, splashes and contact transmission and may reduce
but not eliminate any remaining aerosol hazard. This therefore is in line with the current
recommendations in the policy surrounding the use of a respirator for aerosol generating procedures.

Finally, the results of a recent twenty four hour simulated pandemic flu outbreak study undertaken by
Phin et al were published (Phin et al., 2009). Although the scope of the transmission based precautions
model policies does not cover outbreak situations the results clearly illustrate that increased levels of
all PPE, especially facial protection, will be required should such a situation occur.

4.4   Severe Acute Respiratory Syndrome (SARS)

One review of interest was found from the literature search performed for this update (Hui and Chan,
2008) and looked at the published literature surrounding SARS. In relation to the infection control
aspects of the paper, the precautions recommended are strict droplet and contact precautions but the
potential for the virus to convert to an airborne transmission remains debatable and therefore it is
advised that HCWs take adequate respiratory precautions.




Droplet Precautions: Literature Review                                                           April 2009
                                               Page 8 of 16
4.5   Nasal dispersal of Methicillin Resistant Staphylococcus aureus (MRSA)

Healthcare workers as a potential source of MRSA remains a controversial subject area. A review
published in The Lancet Infection Diseases has discussed the latest literature regarding healthcare
workers as potential sources, vectors or victims of MRSA carriage (Albrich and Harbarth, 2008). One
area of interest in relation to the droplet precautions is that of nasal or throat carriage of MRSA by
HCWs known as “cloud healthcare workers” and there is potential to transmit MRSA via droplet
infections such the common cold. However there is no new evidence reviewed on this potential route
of transmission and therefore the existing recommendations from the 2008 droplet precautions review
are still applicable.

4.6   Respiratory Syncytial Virus (RSV)

A recent general review has been published regarding infection control within paediatric settings
(Posfay-Barbe et al., 2008). Among the different areas discussed in the review is the importance of
prevention of respiratory viral infections within these settings due to this population being highly at
risk. The authors recommend that enhanced precautions (i.e. droplet precautions/respiratory etiquette)
should be employed alongside standard infection control precautions. One additional area of infection
control highlighted in this paper is that of visitor screening and concludes that in most countries this
type of precaution takes the form of a visitor’s self assessment of their current health and the use of
education via healthcare workers and posters, leaflets, etc that remind people to stay at home if they
are ill.

A paper describing the use of infection control precautions and the drug palivizumab to control a
potential outbreak of RSV has also been highlighted from the literature search (Kurz et al., 2008). The
rapid implementation of these control measures, which included a number of infection control
precautions such as hand hygiene, use of PPE (gloves, gowns, masks and eye protection), cohorting of
personnel, exclusion of healthcare workers with respiratory symptoms, limiting visitors and
postponing elective admissions, resulted in only the index case being affected by the virus. A paper
reviewing the literature surrounding the prevention and control of RSV also concluded that the use of
adequate hand hygiene techniques, rapid screening of infected patients and cohorting of children and
hospital staff appear to have the greatest effect when controlling the spread of RSV (Groothuis et al.,
2008). Furthermore the use of a combination of strategies to control respiratory infections has been
highlighted as being the most effective method in another paper looking at four years data of
nosocomial viral infections in a paediatric ward (Gomez-Villa et al., 2008).

Whether droplet precautions are required to prevent the spread of RSV remains a contentious issue and
there is still a lack of sound scientific evidence to support either the use of full droplet precautions
including a surgical mask, or the use of contact precautions alone. This issue will be revisited if new
evidence is published which would result in a change of recommendation from the current advice.

4.7   Epidemiologically Important Organisms

A draft public health methodology for the prioritisation of research, surveillance and other public
health activities has been published in Eurosurveillance (Krause, 2008). The methodology attempts to
increase the standardisation and transparency of the prioritising of pathogens for surveillance, based
on a set of 12 criteria. The results from these criteria are further refined by the use of a weighted
system to normalise the results. One of the advantages of this system is that the status of each
organism is easily updated, if for example a vaccine becomes available. This method may be useful for
consideration in decision making processes and prioritisation for introduction of surveillance, or for
areas perhaps requiring new guidelines.

Droplet Precautions: Literature Review                                                         April 2009
                                              Page 9 of 16
4.8   Respiratory Hygiene (Cough Etiquette)/Spatial Separation

A survey commissioned by the Department of Health as part of their long running “Catch it, Bin it,
Kill it” campaign found from the results of the people interviewed that many assumed that using their
hands when coughing or sneezing instead of using tissues was the best method to reduce the spread of
infectious agents that cause the common cold, flu and other illnesses (DH, 2008). Another interesting
finding from this study was that many did not associate coughing with the spread of respiratory illness
and thought that only sneezing played a part in this. Therefore it could be concluded from these
findings that further work is needed to make people more aware of the procedure for practicing good
respiratory hygiene.

A “self administered questionnaire” study conducted in the USA assessed the use of the
recommendations for cough etiquette and spatial separation as described in the CDC respiratory
infection control guidelines (Turnberg et al., 2008). One particular area looked at by the researchers
was the effectiveness of the visual alerts that ask patients to inform a member of staff that they have
respiratory symptoms when arriving at the emergency/primary care department. While the nurses and
doctors thought that the signage was adequate, the administrative staff did not and stated that the
existing one needed to be improved. It was reported that generally nurses and administrative staff
would offer a mask to a patient if they were coughing/sneezing. The results for compliance with
spatial separation were less promising as it was reported to happen more in the emergency departments
than the primary healthcare settings. The authors believe this difference in the results could be
attributed to the differences in the built environment of these two settings. This challenge has also
been highlighted in a recent general review on infection control for paediatric settings (Posfay-Barbe
et al., 2008). The use of spatial separation will remain a challenge in healthcare settings that have little
or no access to single rooms, however, a Scottish Government Chief Executive Letter (CEL) (SG,
2008) has been released stating that all new build hospitals and healthcare facilities that provide
inpatient care are now required to have 100% single rooms. In addition, when refurbishing major
healthcare facilities a minimum of 50% single rooms will be required.




Droplet Precautions: Literature Review                                                            April 2009
                                               Page 10 of 16
                                            5    Conclusions

5.1     Transmission Based Precautions

      A general review has been published highlighting non-pharmacological interventions for the
      prevention of HAIs.

         o The overall message given is that a combination of precautions is better than using an
           individual precaution and this can be applied to any transmission based prevention strategy.

      The infection control precautions produced by Siegel et al (used as the basis for the first
      transmission based precautions) are also the recommended infection control precautions in the
      SHEA/APIC Guideline for the prevention and control of infection in long term care facilities.

      In August 2008 Health Facilities Scotland completed the implementation of the national colour
      coding system for domestic cleaning materials and equipment.
         o This system, based on the National Patient Safety Agency’s colour coding system released
           in England and Wales, ensures that cleaning items cannot be used in multiple areas,
           reducing the potential cross contamination to occur.

         o It specifies that cleaning items such as cloths, buckets, aprons etc should be yellow for
           isolation areas.

5.2     Influenza

      From the results of the literature search a number of papers were found in relation to the influenza
      virus.

      There is still debate regarding the potential route of transmission according to one recent review
      article.

         o The authors conclude that there may be too much focus on the transmission of this virus via
           large droplets, however, although they reach this conclusion they do not give any
           recommendation in this regard and conclude that further study is required.

      A rapid communication has been released in Eurosurveillance regarding the public health
      implications of Influenza B outbreaks in the UK for 2007/08 within closed settings such as care
      homes.

         o It is interesting to note that no outbreaks were reported in Scotland with the majority being
           reported in England.

         o Most outbreaks occurred in care homes where vaccine coverage was >70% and therefore
           highlights the importance of not relying on vaccine alone when controlling outbreaks and
           that strict enforcement of infection control measures are vital to prevent spread.

      A case control study looking at the clinical features of influenza has also stated that rapid testing
      and isolation precautions are vital to slowing the spread of the virus and the implementation of
      control measures has also proved effective in the management of an influenza outbreak in a locked
      behavioral health unit.


Droplet Precautions: Literature Review                                                           April 2009
                                                Page 11 of 16
      A paper looking at the effectiveness of 3 alcohol based hand rubs against the influenza virus strain
      H1N1 has been recently published and confirms the previous recommendations that both these
      methods of hand hygiene are viable. Additionally the use of alcohol based hand rub allows for a
      reduced time to perform hand hygiene and less irritation to the skin.

5.3     Knowledge and Compliance with PPE

      The papers found relating to PPE from the literature search mainly assessed the knowledge and
      compliance with PPE and especially the use of facial protection.

      One study evaluated the effectiveness of an online infection control course for improving the
      selection and procedure used.

         o It concluded that the required PPE and procedure for donning and removing it for droplet
           precautions is confusing to HCWs and that the influence of online training has a positive
           effect on this in this particular study population. However the study has some potential
           limitations that may have affected the results.

      A study assessed the HCW’s compliance to the recommended CDC respiratory infection control
      guidelines in emergency and primary healthcare environments.

         o From the assessment of the different medical centres/job types it was found that one quarter
           or less of the participants in this study considered the use of eye protection or a mask when
           attending to patients that are sneezing or coughing.

         o This lack of compliance could possibly be due to practical restrictions preventing the
           achievement of the recommended practices.

      Another study looked at factors that influence nurses’ compliance with facial protection.

      o Five factors were found to influence compliance (full time work status, greater than 5 years
        experience as a nurse, a belief that media coverage of infectious diseases impacts on risk
        perception and work practices, at least monthly use of facial protection and organisational
        support for health and safety)

      The results of a study looking at the performance of surgical masks was assessed and although
      they relate to the potential use of surgical masks for droplet nuclei rather than large droplets the
      results do strengthen the current recommendations included in the droplet precautions policy.

      A Health and Safety Executive report looking at the performance of surgical masks supported the
      current recommendations given in the policy by concluding that if used in the proper manner they
      can provide ample protection against large droplets, splashes and contact transmission and may
      reduce but not eliminate any remaining aerosol hazard.

5.4     Severe Acute Respiratory Syndrome (SARS)

      One review paper of interest was found from the literature search for this update and recommends
      strict droplet and contact precautions, however, it is advised that HCWs take adequate respiratory
      precautions as the potential for the virus to convert to an airborne transmission remains debatable.




Droplet Precautions: Literature Review                                                              April 2009
                                                 Page 12 of 16
5.5     Nasal dispersal of Methicillin Resistant Staphylococcus aureus (MRSA)

      Healthcare workers as a potential source of MRSA remains a controversial subject area.

      A review has been published regarding the latest literature on the topic of healthcare workers as
      potential sources, vectors or victims of MRSA carriage, however, there is no new evidence
      reviewed on droplet infections as a potential route of transmission making the existing
      recommendations from the 2008 droplet precautions review still applicable.

5.6     Respiratory Syncytial Virus

      A recent general review has been published regarding infection control within paediatric settings
      and recommended that enhanced precautions (i.e. droplet precautions/respiratory etiquette) should
      be employed alongside standard infection control precautions.

         o One additional area of infection control highlighted in this paper is that of visitor screening
           taking the form of a visitor’s self assessment of their current health and the use of
           education via various methods.

      A paper describing the use of infection control precautions and the drug palivizumab to control a
      potential outbreak of RSV has also been highlighted from the literature search

         o The rapid implementation of these control measures resulted in only the index case being
           affected by the virus.

      A further two papers reviewing the literature surrounding the prevention and control of RSV also
      concluded that the use of a combination of strategies appears to have the greatest effect when
      controlling the spread of RSV.

      Whether droplet precautions are required to prevent the spread of RSV remains a contentious issue
      and there is still a lack of sound scientific evidence to support either the use of full droplet
      precautions including a surgical mask, or the use of contact precautions alone. This issue will be
      revisited if new evidence is published which would result in a change of recommendation from the
      current advice.

5.7     Epidemiologically Important Organisms

      A draft public health methodology for the prioritisation of research, surveillance and other public
      health activities has been published in Eurosurveillance.

      This method may be useful for consideration in decision making processes and prioritisation for
      introduction of surveillance, or for areas perhaps requiring new guidelines.

5.8     Respiratory Hygiene (Cough Etiquette)/Spatial Separation

      A survey commissioned by the Department of Health found that many people assumed that using
      their hands when coughing or sneezing instead of using tissues was the best method to reduce the
      spread of infectious agents that cause the common cold, flu and other illnesses.

      A “self administered questionnaire” study conducted in a number of US emergency departments
      and primary healthcare settings assessed the use of the recommendations for cough etiquette and
      spatial separation as described in the CDC respiratory infection control guidelines.
Droplet Precautions: Literature Review                                                           April 2009
                                                Page 13 of 16
       o It was found that nurses and doctors thought the signage for cough etiquette was adequate
         while the administrative staff did not and stated that the existing one needed to be
         improved.

       o Generally nurses and administrative staff would offer a mask to a patient if they were
         coughing/sneezing.

       o The results for compliance with spatial separation were less promising and varied in each
         of the settings possibly due to differences in the built environment.

   A recent Scottish Government Chief Executive Letter states that all new build hospitals and
   healthcare facilities that provide inpatient care are now required to have 100% single rooms.

       o In addition, when refurbishing major healthcare facilities a minimum of 50% single rooms
         will be required.




Droplet Precautions: Literature Review                                                       April 2009
                                            Page 14 of 16
                                         6   Key References
Albrich, W. C. and Harbarth, S. (2008) Health-care workers: source, vector, or victim of MRSA?, The
Lancet Infectious Diseases, 8, 289-301.

Babcock, H. M. M. D., Merz, L. R. P., Dubberke, E. R. M. D. and Fraser, V. J. M. D. (2008) Case-
Control Study of Clinical Features of Influenza in Hospitalized Patients, Infection Control & Hospital
Epidemiology October, 29, 921-926.

Curtis, L. T. (2008) Prevention of hospital-acquired infections: review of non-pharmacological
interventions, Journal of Hospital Infection
Special edition: Surveillance of Hospital Acquired Infection, 69, 204-219.

Department of Health (2008) Respiratory and hand hygiene survey published, DH, London [avaliable
online] http://www.dh.gov.uk/en/News/Recentstories/DH_083055.

Gomez-Villa, R. J. M. D., Comas-Garcia, A., Lopez-Rojas, V. M. D., Perez-Gonzalez, L. F. M. D.,
Sanchez-Alvarado, J. B. S., Salazar-Zaragoza, R. B. S., Ruiz-Gonzalez, J. M. M. S., Alpuche-Solis, A.
G. P. and Noyola, D. E. M. D. (2008) Effect of an Infection Control Program on the Frequency of
Nosocomial Viral Respiratory Infections, Infection Control & Hospital Epidemiology June, 29, 556-
558.

Grayson, M. L., Melvani, S., Druce, J., Barr, I. G., Ballard, S. A., Johnson, P. D., Mastorakos, T. and
Birch, C. (2009) Efficacy of soap and water and alcohol-based hand-rub preparations against live
H1N1 influenza virus on the hands of human volunteers, Clinical Infectious Diseases, 48, 285-91.

Groothuis, J., Bauman, J., Malinoski, F. and Eggleston, M. (2008) Strategies for prevention of RSV
nosocomial infection, Journal of Perinatology, 28, 319-23.

Health Facilities Scotland (2008) Colour Coding For Hospital Cleaning Materials and Equipment,
HFS, Glasgow.

Hon, C. Y., Gamage, B., Bryce, E. A., LoChang, J., Yassi, A., Maultsaid, D. and Yu, S. (2008)
Personal protective equipment in health care: can online infection control courses transfer knowledge
and improve proper selection and use?, American Journal of Infection Control, 36, e33-7.

Health and Safety Executive (2008) Evaluating the protection afforded by surgical masks against
influenza bioaerosols - Gross protection of surgical masks compared to filtering facepiece respirators,
HSE, London.

Hui, D. S. and Chan, P. K. (2008) Clinical features, pathogenesis and immunobiology of severe acute
respiratory syndrome, Current Opinion in Pulmonary Medicine, 14, 241-7.

Krause, G. (2008) Prioritisation of infectious diseases in public health - call for comments,
Eurosurveillance, 3, pii=18996.

Kurz, H., Herbich, K., Janata, O., Sterniste, W. and Bauer, K. (2008) Experience with the use of
palivizumab together with infection control measures to prevent respiratory syncytial virus outbreaks
in neonatal intensive care units, Journal of Hospital Infection, 70, 246-252.




Droplet Precautions: Literature Review                                                          April 2009
                                              Page 15 of 16
Mook, P., Ellis, J., Watson, J., Thompson, C., Zambon, M., McMenamin, J., Smyth, B., Thomas, D.
and Pebody, R. (2008) Public health implications of influenza B outbreaks in closed settings in the
United Kingdom in the 2007/08 influenza season., Eurosurveillance, 13, pii=18986.

Nichol, K., Bigelow, P., O'Brien-Pallas, L., McGeer, A., Manno, M. and Holness, D. L. (2008) The
individual, environmental, and organizational factors that influence nurses' use of facial protection to
prevent occupational transmission of communicable respiratory illness in acute care hospitals,
American Journal of Infection Control, 36, 481-487.

National Patient Safety Agency (2007) Safer Practice Notice 15 - Colour coding hospital cleaning
materials and equipment, NPSA, London.

Oberg, T. and Brosseau, L. M. (2008) Surgical mask filter and fit performance, American Journal of
Infection Control, 36, 276-282.

Phin, N. F., Rylands, A. J., Allan, J., Edwards, C., Enstone, J. E. and Nguyen-Van-Tam, J. S. (2009)
Personal protective equipment in an influenza pandemic: a UK simulation exercise, Journal of
Hospital Infection, 71, 15-21.

Posfay-Barbe, K. M., Zerr, D. M. and Pittet, D. (2008) Infection control in paediatrics, The Lancet
Infectious Diseases, 8, 19-31.

Risa, K. J., McAndrew, J. M. and Muder, R. R. (2009) Influenza outbreak management on a locked
behavioral health unit, American Journal of Infection Control, 37, 76-78.

Scottish Government (2008) Provision of single room accommodation and bad spacing, CEL 48
(2008), SG, Edinburgh.

Siegel, J., Rhinehart, E., Jackson, M., Chiarello, L. and The Healthcare Infection Control Practices
Advisory Committee (2007) Guideline for Isolation Precautions: Preventing Transmission of
Infectious Agents in Healthcare Settings 2007, June 2007.

Scottish Intercollegiate Guidelines Network (2004) SIGN 50: A guideline developers' handbook,
SIGN, Edinburgh.

Smith, P. W., Bennett, G., Bradley, S., Drinka, P., Lautenbach, E., Marx, J., Mody, L., Nicolle, L. and
Stevenson, K. (2008) SHEA/APIC Guideline: Infection prevention and control in the long-term care
facility, American Journal of Infection Control, 36, 504-535.

The AGREE Collaboration (2001) Appraisal of Guidelines For Research & Evaluation (AGREE)
Instrument, September 2001.

Turnberg, W., Daniell, W., Seixas, N., Simpson, T., Van Buren, J., Lipkin, E. and Duchin, J. (2008)
Appraisal of recommended respiratory infection control practices in primary care and emergency
department settings, American Journal of Infection Control, 36, 268-275.

Weber, T. P. and Stilianakis, N. I. (2008) Inactivation of influenza A viruses in the environment and
modes of transmission: a critical review, Journal of Infection, 57, 361-73.




Droplet Precautions: Literature Review                                                          April 2009
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