Aug 21, 2003
A Milder-Than-SARS Illness Linked with the SARS-Coronavirus in Canada?
Frequently Asked Questions about the ‘Non-Severe Acute Respiratory Syndrome’ in British Columbia linked to a virus similar to the SARS coronavirus
This communication summarizes in FAQ format the initial reports from Aug 14-21 of an acute respiratory disease in one long-term facility in British Columbia, Canada, that have appeared from the British Columbia Centre for Disease Control (www.bccdc.org), the US CDC (www.cdc.gov/ncidod/sars 8/14), ProMed (www.promedmail.org), Health Canada (via Toronto and Hong Kong colleagues), the New Scientist (www.newscientist.com 8/20) and the media (Vancouver Sun 8/20 and 8/21, Toronto Star 8/14, NY Times online 8/20, and 8/21 p. A6, Washington Post 8/21 p. A19, and the Wall St. Journal 8/20 p.D3).
1. Q: Clinically, is this “Severe Acute Respiratory Syndrome (SARS)”?
A: No. Clinically, this respiratory illness in elderly residents and staff of a long-term facility is much more mild that SARS, causes less pneumonia and has a lower case fatality rate than SARS, and does not usually cause fever ( found in only ~ 20% of 94 elderly patients).
2. Q: Then why is this illness potentially linked with the SARS-coronavirus?
A: Because preliminary tests in two separate Canadian labs have shown evidence of the SARS-coronavirus in a limited number of patients.
3. Q: What is the case definition of this illness?
A: According to Dr. David Patrick of the British Columbia Centre for Disease Control (see his detailed Aug 20 ProMED posting): “For the purposes of this description, the case definition in use is one of any respiratory symptoms (cough, rhinitis, fever, etc.) after 1 Jul 2003”.
4. Q: Where is this outbreak occurring?
A: In the Kinsmen Place Lodge long-term care facility, in Surrey (east of Vancouver), British Columbia, Canada.
5. Q: Is there another outbreak in British Columbia at this time?
A: No. Updated news this afternoon reports that lab tests for SARS coronavirus are negative for patients with a “cold”-like respiratory illness at a 2nd facility for the elderly in the same area as the Kinsmen Place Lodge (Vancouver Sun 8/21, www.CNN.com/health 8/21). Thus, the initial reports of a 2nd facility being involved (Vancouver Sun 8/20; NY Times 8/21, New Scientist.com 8/21) have not been confirmed.
6. Q: How many people have become ill so far in the single involved facility?
A: ~143 persons. 94 (of 142 elderly or disabled facility residents) and 49 (of 160 facility staff) have become ill.
7. Q: When did this illness start and when did it peak?
A: The illness started July 2nd and the peak occurred in late July. A decreasing number of cases have occurred during August. The epidemic curve for Kinsmen Place Lodge in Surrey, BC, is posted on the BC CDC website (www.bccdc.org).
8. Q: What lab tests have been done to identify this disease?
A: According to Dr. Patrick from British Columbia (Aug 20 www.promedmail.org) :RT- PCR (reverse transcriptase polymerase chain reaction) testing was reactive for the SARS-coronavirus on 9/19 patients using several PCR primer sets to detect different parts of the virus; the PCR was done in two separate labs (to control for lab error) at the National Microbiology Lab in Canada. Antibody tests were positive for SARS coronavirus in 4 of 7 patients initially tested. Lab tests for ~10 other causes of respiratory disease have been negative (except for 4 patients positive for human metapneumovirus). Sera has been sent to the US CDC, and a WHO virologist is at the Canadian National Lab in Winnipeg.
9. Q: Has this putative virus been grown in culture and has the full genetic (nucleotide) sequence been compared with the SARS-coronavirus?
A: No. To my knowledge, no coronavirus has yet been isolated in culture from these patients, and only ~ 2% of the genome of this virus has been identified by PCR. However, these key regions making up 2% of the viral genome appear consistent with the SARS-coronavirus.
10. Q: Have any staff developed pneumonia or died?
A: No. None of the 49 staff have been hospitalized, developed pneumonia or died (unlike SARS). Their illness is mild with cough and coryza.
11. Q: What are the clinical findings in the residents of the facility?
A: In the 94 ill residents, pneumonia has been found in 10, of whom 9 have been hospitalized. Initial reports are of a lobar pneumonia on chest X-ray. 60% of those ill had rhinitis, 20% fever, and 62% cough.
12. Q: Have any residents of this long-term care facility died?
A: Yes. Whereas the case fatality rate of SARS in persons 65 and older is > 50% (WHO May 7th update), the case fatality rate so far is much lower for this illness in British Columbia. Dr. Patrick reported (Aug 20 ProMED) that baseline mortality at this facility is about 8 persons every two (2) months. In the 7 ˝ weeks since this illness began, 11 persons have died. 6 of these 11 persons had pneumonia at the time of death, 3 had progressive palliative conditions, and 2 had vascular causes of death. Autopsy results are preliminary.
13. Q: What Infection Control measures have been put in place?
A: SARS-type infection control measures have been put in place. These include respiratory precautions and isolation of ill residents, quarantine at home for staff who were exposed prior to use of full-respiratory precautions, increased hand-washing, twice-daily temperature checks for staff, closure of the facility to visitors and new admissions, and restriction of staff from working at any other facilities.
14. Q: What do outbreaks like this one in British Columbia mean for the next autumn-winter respiratory illnesses-influenza (? SARS) season?
A: We have a long road ahead. See the new World Health Organization (WHO) August 14th guidelines for “Alert, verification and public health management of SARS in the post-outbreak period”, noting the role of laboratory testing for the SARS-coronavirus. The urgent need for a rapid diagnostic tests for SARS is evident. Also note the explicit WHO emphasis July 3rd (Update 94) on influenza vaccination this year since influenza can be clinically indistinguishable from SARS.
15. Q: How does the WHO define a new outbreak of SARS?
A: “A new outbreak of SARS is defined as the occurrence of one or more clinically compatible, laboratory-confirmed cases of SARS in any country based on definitive laboratory investigations. The reappearance of SARS in the human population would be considered a global public health emergency. For the purposes of the international reporting of SARS in the post-outbreak period, Member States are requested to inform WHO of laboratory-confirmed cases only.” (Section 3.5, WHO Aug 14, www.who.int/csr/sars/postoutbreak).
Daniel R. Lucey, MD, MPH
Director, Center for Biologic Counterterrorism & Emerging Diseases
Institutes for Innovation in Medicine
Washington Hospital Center
110 Irving St NW
Washington DC 20010
Consultant to the DC Department of Health
Consultant to DC Hospital Association
e-mail: Daniel.R.Lucey@Medstar.net