Summary of Severe Acute Respiratory Syndrome (SARS) Cases: Canada and International

May 14, 2003

Canada

Since May 7, 2003, no additional probable cases of SARS have been reported. The total number of probable cases reported to date in Canada, by reported symptom onset date and type of exposure (where known), is provided below (Figure 1).

 

Figure 1: Number of probable cases of SARS in Canada by symptom onset date and exposure type: February 23 to May 14, 2003
(N=141*, excludes 1 for whom onset date is unknown)

* Epi Curve may change as information on cases is updated by P/T Ministries of Health
** Presently, the Other/Autres category includes 6 individuals associated with the Bukas LoobSa Diyos Covenant Community (BLD) group.

Source: Provincial-Territorial Ministries of Health

 

The current status of all probable and suspect cases in Canada as of May 14, 2003 is presented in Tables 1 and 2. Of the 319 probable and suspect SARS cases identified to date, most (82%, 263 of 319) have been discharged from hospital or have recovered at home. An additional 20 of the 319 (6%) suspect and probable cases are currently stable or recovering at home. Most of the case fatalities reported have occurred in patients with underlying illness, and nearly all were elderly patients over the age of 70 years.

Table 1: Current Status of Probable SARS Cases in Canada During the Previous 10 days

Probable Cases	May 5	May 6	May 7	May 8	May 9	May 10	May 11	May 12	May 13	May 14
Cumulative total*	148	146	146	145	145	143	143	143	143	142
Active cases (currently ill)
Hospitalized	32	30	29	28	26	23	23	21	16	12
At home, currently ill	1	1	0	0	0	0	0	0	0	0
Unknown	0	0	0	0	0	0	0	0	0	0
Total Active Probable	33	31	29	29	26	23	23	21	16	12
Historical cases (recovered and deaths)
Discharged from hospital and recovered, never hospitalized	93	93	95	95	97	98	98	99	104	107
Deaths	22	22	22	22	22	22	22	23	23	23
*Cumulative total of all active and historical probable cases with onset of symptoms on or after February 23, 2003, including cases who have recovered, died or are currently ill.

Table 2: Current Status of Suspect SARS Cases in Canada During the Previous 10 days

Suspect Cases	May 5	May 6	May 7	May 8	May 9	May 10	May 11	May 12	May 13	May 14
Cumulative total*	179	180	183	182	178	178	178	175	178	177
Active cases (currently ill)
Hospitalized	16	16	16	16	15	14	14	13	7	0
At home, currently ill	17	17	18	17	17	19	19	17	19	20
Unknown	0	0	0	0	0	0	0	0	0	0
Total Active Suspect	33	33	34	33	32	33	33	30	26	20
Historical cases (recovered and deaths)
Discharged from hospital and recovered, never hospitalized	145	146	148	148	145	144	144	144	151	156
Deaths	1	1	1	1	1	1	1	1	1	1
*Cumulative total of all active and historical suspect cases with onset of symptoms on or after February 23, 2003 , including cases who have recovered, died or are currently ill.

As of May 14, 2003, a total of 142 individuals who meet the probable case definition and 177 who meet the suspect case definition of SARS have been reported, including 24 deaths (Table 3). Since May 7, 2003, one new suspect case has been reported from British Columbia with symptoms onset on April 25, 2003. As well, an additional death occured on May 11, 2003, in a probable case from Ontario.

Table 3: Cumulative Number of SARS Cases Reported in Canada: May 14, 2003

Province/Territory	Individuals Meeting the Criteria for a:		Number of Deaths**
	Probable Case*	Suspect Case*
British Columbia	4	44	0
Alberta	0	6	0
Saskatchewan	0	1	0
Manitoba	0	0	0
Ontario	138	120	24**
Quebec	0	0	0
Nova Scotia	0	0	0
Newfoundland	0	0	0
New Brunswick	0	2	0
Prince Edward Island	0	4	0
Nunavut	0	0	0
North West Territories	0	0	0
Yukon	0	0	0
TOTAL	142	177	24
* Persons may be excluded from the probable or suspect case list if another cause is identified to fully explain their illness. Case numbers may change as cases are reclassifed based on new information (e.g. disease progression or re-evaluation of the data). ** 23 of 24 deaths were probable cases, while 1 was a suspect case. Another death, not included in this total count occurred in a 46-year-old female who died in the Philippines on April 14, 2003. It is believed she may have contracted SARS while in Toronto.

The current evidence suggests that respiratory droplet transmission, requiring close contact with a case of SARS, is the main mode of transmission. Based on data available from 42 probable or suspect cases with a single known contact with a SARS case, the mean incubation period is 5 days (median 4 days, range 2 to 10 days).

In the province of Ontario, the majority of cases have been associated with specific transmission settings, such as household, hospital, and specific community groups or settings. In community settings, a total of 20 probable and 11 suspect cases of SARS were identified in a religious community group (BLD cluster), however among these, exposure was attributed mainly to health care and household settings. Four members of the index family who are members of this religious group had contact with a SARS case in the emergency room of a Toronto hospital on March 16, 2003. Three of these developed SARS after the exposure, and the infection subsequently spread through their extended family. By April 12, 2003, all members of the religious group were quarantined, in an effort to contain any further spread within and outside of this social network. In total, fourteen members of the index family, 3 health care workers and 14 other religious group members have been identified as probable or suspect cases of SARS. The religious group has since completed their quarantine with no further cases identified through extensive case finding and contact tracing efforts.

Following the implementation of strict infection control measures in all Ontario hospitals, transmission of SARS to hospital workers has decreased substantially. Despite these measures, there have been reports of transmission to hospital workers. In 3 different hospitals, transmission has been attributed to exposure during difficult intubations. In two, undiagnosed patients were identified as the source of transmission for 7 hospital workers. Compliance with infection control precautions by staff may not have been complete. In the third, a SARS patient was identified as the source of infection for 9 hospital staff during a difficult intubation. In addition, transmission of SARS to 6 hospital staff has also been identified in 5 different low-risk SARS units. Initial investigation suggests that transmission in these settings has occurred while staff were wearing required personal protective equipment and following all recommended infection control precautions. A comprehensive investigation is presently underway involving experts from Health Canada, the U.S. Centers for Disease Control and Prevention (CDC), the Province of Ontario, and Toronto Public Health.

In British Columbia, the fourth probable case (onset April 4, 2003) was a health care worker who was exposed to the second travel-related probable case in that province. There are no further cases associated with this this 4th probable case.

Travellers who have returned from an affected area in Asia and their close contacts account for the remaining cases in Ontario and the other provinces.
The list of at-risk settings in the province of Ontario can be obtained at the following address: http://www.health.gov.on.ca/english/public/updates/
archives/hu_03/hu_sars.html

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International

Since November 1, 2002, 7,627 cases of SARS (7,485 outside of Canada) have been reported to the World Health Organization (Table 4). Outside of mainland China, the vast majority of reported cases have originated from Hong Kong, Special Administrative Region of China. As of May 14, 2003, 564 deaths have been reported outside of Canada, the majority (494) of which were reported in mainland China and Hong Kong, SAR.

The WHO is reporting that the severity of illness in cases linked to the previously identified cluster of cases in the Amoy Gardens housing complex is greater, relative to cases derived from other exposure settings. The report indicates that while 20% of Amoy-related cases require intensive care, this is true for only 10% of non-Amoy-related cases. In addition, 66% of Amoy Gardens patients present with diarrhea as a symptom, compared to only 2% to 7% of cases in other related-outbreaks.

Table 4: Cumulative Number of SARS Cases* and Deaths Reported to the World Health Organisation: November 1, 2002 to May 14, 2003

Country	Number of Cases	Number of Deaths
Australia	6	0
Brazil	2	0
Bulgaria	1	0
Canada	142	24**
China, mainland***	5124	267
China, Hong Kong SAR	1698	227****
China, Macao Special Administrative Region	1	0
China, Taiwan	238	30
Colombia	1	0
Finland	1	0
France	7	0
Germany	9	0
India	3	0
Indonesia	2	0
Italy	9	0
Kuwait	1	0
Malaysia	7	2
Mongolia	9	0
New Zealand	1	0
Philippines	10	2
Republic of Ireland	1	0
Republic of Korea	3	0
Romania	1	0
Singapore	205	28
South Africa	1	1
Spain	1	0
Sweden	3	0
Switzerland	1	0
Thailand	8	2
United Kingdom	4	0
United States	64*	0
Vietnam	63	5
TOTAL	7627	588
*Cumulative number of cases includes deaths. Case definitions vary from one country to another. Only probable cases are being reported by all countries. The US will no longer be reporting suspect cases under investigation as of April 21, 2003. **23 of 24 deaths were in probable cases and 1 was in suspect cases. ***The start of the period of surveillance was changed to November 1 2002 to capture cases of atypical pneumonia in China that are now recognised as being cases of SARS. ****One death attributed to Hong Kong SAR occurred in a case medically transferred from Vietnam. Source: http://www.who.int/csr/sars/country/2003_05_14/en/, with updates from Canada.