- Vancouver health authorities tried to set the record
straight with the Asian press last weekend regarding a mysterious viral
outbreak in two nursing homes in the province.
-
- It was concerned that the outbreak, which has infected
more than 100 elderly people so far, was being portrayed as Sars. As a
result, controls at Hong Kong's airport had been stepped up, the Taiwanese
had cancelled trips to the province, and Singapore doctors were told to
be on the alert.
-
- But the world must be told that what the elderly residents
have is the coronavirus OC43, which causes the common cold, said Dr David
Patrick, director of epidemiology at the British Columbia Centre for Disease
Control, at a press conference in Vancouver.
-
- One scientist joining in by teleconference who did not
entirely agree, however, was Dr Frank Plummer, who heads Canada's National
Microbiology Laboratory in Winnipeg.
-
- He does not answer to the authorities in Vancouver, as
the Winnipeg laboratory is one of 11 which the World Health Organisation
(WHO) uses for its global surveillance of infectious diseases.
-
- Of 29 specimens sent to Dr Plummer so far from the nursing
homes, 12 have tested positive for Sars.
-
- The laboratory also found antibodies to Sars in some
patients, including one who had died from pneumonia, a sure sign that these
patients had contracted Sars at some point.
-
- Dr Plummer said that his laboratory had found 'and continues
to find' the Sars virus in samples sent from the two homes.
-
- Also significant, he said, was that people who tested
positive for the OC43 virus were generally not the same as those who tested
positive for the Sars virus.
-
- In other words, there were three possible groups of cases
from the homes: Those with the OC43 virus; those with the Sars virus; and
those with both OC43 and Sars or, alternatively, a virus made from parts
of both viruses.
-
- Was he mistaken? After all, even the best laboratories
make mistakes, said Dr Edison Liu, who heads the Genome Institute of Singapore,
to The Straits Times.
-
- Still, it seems highly unlikely that 12 different samples
could have somehow become contaminated, wrongly generating the Sars sequences
in a WHO laboratory.
-
- For whatever reason, the Vancouver authorities have lifted
the quarantines on the two nursing homes, which implies that Dr Plummer
got it wrong.
-
- If he did, Canada owes the rest of the world an explanation
on how he was mistaken and how such errors can be avoided in the future.
-
- But if he got it right, then to say the outbreak was
a 'summer cold' caused by OC43 could be judged premature, even irresponsible.
-
- Dr Henry Niman, a Harvard Medical School bioengineer
who has followed the trajectory of Sars closely, told The Straits Times:
'Dr Plummer's data is either something the Canadians are too embarrassed
to talk about, or there are both OC43 and Sars in Vancouver but the data
is being misrepresented to the world and the Canadian media is buying it.'
-
- The Winnipeg laboratory has stood by its findings and
says the outbreak could be from a recombinant virus made from parts of
the Sars and OC43 viruses.
-
- 'If so, this would be cause for great concern, considering
the very high rate of transmission of this bug within the homes,' said
Dr Niman.
-
- Dr Plummer himself has cautioned: 'We can't rule out
anything at this point, really. How all of these different findings fit
together, I think, remains a matter for further study.'
-
- Such comments have annoyed provincial health officials
whose fears of the economic fallout from a Sars outbreak may be causing
them to play down the situation, said Dr Niman.
-
- Disconcertingly, Canadian health officials did not respond
to the Winnipeg data at their weekend press conference. Symptoms of this
outbreak simply did not meet the case definition required by the WHO, they
said.
-
- Perhaps they were not aware that, in May, at the height
of the Sars outbreak, the Hong Kong Geriatrics Society issued an alert
saying that old people with Sars may have non-typical symptoms.
-
- They may not even cough when they have pneumonia, but
show merely a shortness of breath, and then only when they exert themselves
a little, like sitting up in bed.
-
- Because the elderly tend to have weaker immune defences,
they could have a very mild fever or none at all. Fever is a defence mechanism
which tries to slow down viruses from replicating by raising the body's
temperature above the normal range.
-
- In fact, three of Toronto's first 10 Sars cases earlier
this year had lower temperatures than healthy adults, as low as 35.5 deg
C to 36.5 deg C.
-
- The bottom line is: Health-care workers must be very
watchful when diagnosing the elderly for Sars.
-
- Instead, health officials in Vancouver seem bent on denial.
-
- Whatever it is, as Acting Health Minister Khaw Boon Wan
has said pointedly: The bug has caused more than 100 infections and some
deaths in Vancouver. Because of that, Singapore will treat it as Sars until
it is proven otherwise.
-
- Now, that's logic the Asian media can understand.
-
- Copyright @ 2003 Singapore Press Holdings. All rights
reserved.
-
- http://straitstimes.asia1.com.sg/commentary/story/0,4386,206776,00.html
|
