Drs Du Buisson, Bruinette & Kramer Drs Du Buisson, Bruinette by monkey6


More Info
									Drs Du Buisson, Bruinette & Kramer                                  Lab Update No. 17
                                                                    Lab Update No. 17


                               A BRIEF OVERVIEW

                                     APRIL 2003


     Severe Acute Respiratory Syndrome (SARS) is an acute respiratory tract infection,
     which appears to have originated in the Far East.

     The probable cause is a “new” or previously unrecognised Corona virus. Spread is via
     the respiratory route following droplet exposure and most cases appear to be the
     result of “close contact” transmission. However, less direct respiratory transmission is
     suspected in some cases and the role of air conditioning, etc. is not clear as yet. The
     incubation period is short: 2 to7 days, with 3 to 5 days being more common.

     The first case was reported in Hanoi in February this year. The clinical disease may be
     severe, with a significant number of patients requiring ventilation. The
     reported mortality is 3 to 5%. By early April more than 2500 probable cases with over
     100 deaths had been reported to the WHO. The vast majority of cases have
     occurred in China (incl. Hong Kong), Singapore and Vietnam. To date, at least 13
     countries (incl. Canada, USA, European countries) have reported cases - most of
     which had been imported, i.e. history of (air) travel from an affected country in the

     Local transmission from imported cases has been described in some countries,
     although this can be limited by strict implementat ion of cross-infection precautions.

     Clinical and epidemiological (e.g. contact and travel) data must initially be used to
     assess the likelihood of SARS.

     There is no routine diagnostic test available at present. A PCR test for the possible
     causative virus is available at the NICD. Specimens may also be collected for
     possible retrospective confirmation of SARS cases.

     In South Africa specimens should be sent to the NICD, after consultation (see below)
     and only if clinical and epidemiological criteria for suspicion are fulfilled.

                                                                                Page 1 of 4
                                                                                Page 1 of 4
Drs Du Buisson, Bruinette & Kramer                                Lab Update No. 17
                                                                  Lab Update No. 17

2.   DEFINITIONS (WHO, March 2003)

     Suspect Case of SARS

     A person presenting after 1 February 2003 with history of:

     •      high fever (>38 degree Celsius)


     •      one or more respiratory symptoms including cough, shortness of breath,
            difficulty breathing

     AND one or more of the following:

     •      close contact*, within 10 days of onset of symptoms, with a person with
            suspected or confirmed SARS and/or

     •      history of travel, within 10 days of onset of symptoms, to an area in which
            there are reported foci of transmission of SARS.

     Probable Case of SARS

     A suspect case with chest X-ray findings of pneumonia or Respiratory Distress


     A suspect case with an unexplained respiratory illness resulting in death, with an
     autopsy examination demonstrating the pathology of Respiratory Distress Syndrome
     without an identifiable cause.


     In addition to fever and respiratory symptoms, SARS may be associated with other
     symptoms including: headache, muscular stiffness, loss of appetite, malaise,
     confusion, rash and diarrhoea.

     * Close contact means having cared for, having lived with, or having had direct
     contact with respiratory secr etions and body fluids of a person with SARS.

                                                                            Page 2 of 4
                                                                            Page 2 of 4
Drs Du Buisson, Bruinette & Kramer                                 Lab Update No. 17
                                                                   Lab Update No. 17


     •   Isolate patient and limit contact with other persons
     •   Patient to wear theatre mask
     •   Any persons (staff etc.) having contact with patient must wear theatre mask, apron,
         gown and eye protection (i.e. goggles or visor-type mask) and gloves
     •   Consult virologist at NICD before collecting and/or sending specimens:

            Contact persons:
            Dr Lucille Blumberg        082 807 6770
            Prof Barry Schoub          082 908 8049
            Dr Adrian Puren            082 908 8048

            This is critical, as the specimens cannot be processed unless approved through
            prior consultation with NICD personnel!


     •   - Nasopharyngeal aspirate (preferred)
         - Tracheal aspirate
         - Broncho-alveolar lavage
           (add viral transport medium for the above mentioned)

     •   Clotted blood (5 to 10ml)


     In consulting room context: a separate room is recommended (if available).

     Please arrange specimen collection in advance with the laboratory to allow steps to
     be taken to minimise exposure to other patients and staff.

     In hospital context: isolation plus barrier nursing.

     Masks: 3M N95 Particulate Respirator (these are expensive but can be reused) or
     theatre mask plus eye protection plastic visor.


     Management is supportive, including ventilatory assistance if indicat ed.
     Corticosteroids are indicated in patients who are hypoxic and should be administered
     as early as possible for these select ed cases.

                                                                               Page 3 of 4
                                                                               Page 3 of 4
Drs Du Buisson, Bruinette & Kramer                              Lab Update No. 17
                                                                Lab Update No. 17


     Drazen JM. Case clusters of the severe acute respiratory syndrome. N Eng J Med. 31
     March 2003. Editorial published on website www.nejm.org

     Poutanen SM, Low DE, Henry B. Identification of severe acute respiratory syndrome in
     Canada. N Eng J Med, 31 March 2003. Published on website www.nejm.org.

     Tsang KW, Ho PL, Ooi GC. A cluster of cases of severe acute respiratory syndrome in
     Hong Kong. N Eng J Med, 31 March 2003. Published on website www.nejm.org.

Dr Adrian Brink and Dr Jan van den Ende
Department of Clinical Microbiology

                                                                            Page 4 of 4
                                                                            Page 4 of 4

To top