Investigation of a nosocomial outbreak of severe acute respiratory syndrome (SARS) in Toronto, Canada

The authors have stated index case traveled to Hong Kong returning February 2003. The elderly female index purported staying at a Hotel on Kowloon Island where there had been 13 additonal cluster cases.

The basic cluster informaton is contrary to a similar study prepared by authors from Princess Margaret Hospital et al, Hong Kong, China. The 272 cluster patients at this hospital represented the primary Hong Kong outbreak.

I find no reference to any 13 hotel cluster patients that were diagnosed with the corona virus (SARS) admitted to Princess Margaret Hospital. Though, I could be mistaken. And/or it was a different treatment facility where those 13 cluster patients were treated.

Is it posssible upon a new interview of family members that the decedant index case, in fact stayed in Amoy Gardens and/or visited overnight an apartment in Amoy Gardens?

The Princess Margaret study states 170 patients all lived in Amoy Gardens and only one or two were same household. The 170 cluster did not know each other though they all resided there. Other patients were hospital personnel. There was a small grouping whose residence was not indicated. Kowloon is close to Amoy Gardens

This minor discrepancy has an upmost importance in determining several factors. Did the Toronto index patient contract the same strain as Princess Margaret Hospital patients? An unknown vector was suspected and none has been found as yet. Science magazine this month has indicated the feral Asian Civet, but this is not common food in Hong Kong though it does confirm that SARS is 99.5% identical to the corona virus which infects civets.

Is it possible that the deceased index case or her son's blood samples are still available that could be tested for specific protein antibodies not affiliated with SARS, but could possibly provide a clue to the vector?

Your report is excellent, but does not confirm a direct tie to the major outbreak in Hong Kong. It is possible that the index case family, if Chinese did not have translators available when admitted to the Toronto hospital. The family representative who admitted the index case (since the patient was severely ill) might have mis-spoke or not have known all facts of the Hong Kong trip. They could not realize how pertinent detailed information would become to medical investigators.

I would appreciate hearing from Dr. Bonnie Henry on this issue or any of her pier's. My research concerns a possible novel vector that protein antibodies could confirm if present in blood samples.

Mr. B. Allen Los Angeles, California bcallen33@hotmail.com

Conflict of Interest:

None declared