Hong Kong & WHO seek SARS host

From ANIMAL PEOPLE, May 2003:

HONG KONG–Severe Acute Respirat-ory
Syndrome, the latest flu-like disease among many
to cross from animals to humans in southern
China, had been diagnosed in 3,947 people in
five months as the May edition of ANIMAL PEOPLE
went to press, killing 229 while 1,935 were
fully recovered, according to the latest daily
data summary from the World Health Organization.
As epidemics go, SARS was not especially
serious. The global toll from all forms of flu
ranges from 250,000 to 500,000 deaths per year.
Dengue fever afflicts 50 million people per year.
AIDS is diagnosed at the rate of five million new
cases per year, killing 3.1 million people in
2002.
But few diseases have ever terrified a
city as SARS has terrified Hong Kong–and as
cases turned up in other nations, almost
entirely among recent visitors to Hong Kong, the
panic spread.

“The SARS virus is thought by many health
experts to have made the leap from animals to
humans in Guangdong province,” in China just
north of Hong Kong, CNN explained, “although how
exactly that happened is one of many mysteries
yet to be solved. The virus then spread to Hong
Kong and from there it has been carried by air
travelers to more than 20 countries and
territories.”
Influenza and other flu-like viruses
typically start out as endemic but fairly
harmless infections in birds. Migratory
waterfowl, meeting at summer feeding areas in
the Arctic Circle, share viruses and then
redistribute them around the globe.
Guangdong is the leading influenza
incubating region in the world because the
flooded rice paddies of southern China attract
the world’s largest concentrations of waterfowl,
in proximity to millions of outdoor-raised pigs.
The presence of the pigs is almost always
essential for a new flu virus to mutate into a
form capable of afflicting humans. Typically the
virus passes from ducks or geese to pigs to
people. Rarely does a flu-like virus pass
directly from birds to people or through any
other intermediary hosts.
But the only form of flu known to have
infected people directly from waterfowl emerged
in Hong Kong in 1997, also with a probable
etiology in Guangdong. Five of the first eight
known victims died, making it an exceptionally
deadly if rare flu variant. Most flus kill only
4% of the people they infect, and the fatalities
tend to be among the weakest–often people who
are already desperately ill with some other
condition, such as cancer.
The scariest aspect of SARS, however,
is that despite intensive medical research, the
original animal source of it is still unknown.
It is a member of the coronavirus family, like
the common cold, but does not seem to have
reached humans through the usual
duck-to-pig-to-person linkage.
Theories are many. “It somewhat
resembles several animal viruses,” Canadian
National Microbiology Laboratory scientific
director Frank Plummer told Andre Picard, public
health reporter for the Toronto Globe & Mail.
“It’s somewhere between a mouse corona, a bird
corona, and a cow corona,” Plummer continued.
The possibility that cattle were the
intermediate host seemed to make sense, as at
the time the first case of SARS known to WHO had
occurred in Foshan City, Guangdong, China, a
center of the Chinese cattle industry that
exports beef and other cattle products to Hong
Kong in high volume.
Three days later, Brazilian researchers
Laura Áaneth Villareal Buitrago and Paulo
Educardo Brandao identified a coronavirus in a
chicken which might have offered a clue about
SARS.
But five days after that, as Hong Kong
health officials explored the spread of SARS
among at least 278 residents of the Amoy Gardens
Housing Estate in Kowloon, deputy health
director Leung Pak-yin theorized that cockroaches
were the intermediate host. WHO investigative
team leader Robert Breiman told Leu Siew Ying of
the South China Morning Post that same afternoon
that ducks, chickens, pigs, bats, pangolins,
pigeons, and owls were all possible intermediate
hosts.
A letter-writer to the South China
Morning Post named L. Cho-Tuen Lau, living in
Schomberg, Ontario, Canada, noted that “The
very first outbreak of SARS took place in
precisely the season when the Guangdong natives
were feasting on wild game, particularly
snakes.” Lau explained.
“Are we seeing redress?” Lau continued.
“SARS, Hong Kong flu, and like pestiliences may
well be the price we pay for all the unexamined
and despicable beliefs about bears and their paws
and gall bladders, swifts and the products of
their nests, and the fins of sharks. Let SARS
be a wake-up call,” Lau pleaded. “There is a
great minefield in our traditional beliefs and
practice. Let’s give it a thorough sweep,
disarm these practices, and get ourselves out of
harm’s way.”
Struggling to combat apparently
completely unfounded rumors that dogs, cats,
rabbits, or hamsters were responsible for
transmitting SARS, Hong Kong SPCA acting
exective director Pauline Taylor, DVM, seconded
Lau with her own letter to the South China
Morning Post.
“Eating dogs, cats, birds, snakes,
other reptiles, rats, or any kind of exotic
species only increases our chances of creating a
new virus that may kill our family, friends,
and community,” Taylor declared. “Knowing this,
we must stop archaic if traditional eating
practices.”

Suspect turtles?

Among all the possible animal hosts
mentioned and studied, somehow no one seemed to
mention turtles, or remember the January 2003
warning of Kadoorie Farm & Botanic Gardens senior
fauna conservation manager Gary Ades that the
seemingly insatiable appetite of turtle consumers
in Hong Kong and China could be big trouble–
although Ades meant for turtle species, as many
varieties have been pushed close to extinction.
Kadoorie Farm, in the New Territories,
is the leading wildlife rehabilitation center and
public education facility in Hong Kong. In
December 2001 Kadoorie Farm led a successful
international effort to save 10,000 turtles
seized by Customs officers from a single
smuggling cargo.
“We want people to think about what they
are doing when they consume turtles,” Ades told
Heike Phillips of the South China Morning Post.
“We’re talking about a crisis. Hong Kong is
mainly a transit point, but there are many
turtle soup outlets and also pet shops selling
turtles here,” Ades said.
Even as the SARS panic peaked, however,
the illegal turtle traffic continued, with major
seizures not only in Hong Kong but also in
Vietnam, the nation with the second most SARS
cases, where Hanoi inspectors found 4,159
turtles of five species aboard a Thai Airways
flight from Malaysia, just a few days after
intercepting a similar load on a Singapore
Airlines flight.
Turtles live in the same wetlands as
migratory waterfowl. Turtle consumption is
strongest among the centers of Chinese and
Vietnamese affluence where the most SARS cases
occurred. Medicinal foods made from turtles are
a major part of Chinese traditional medicine, so
people of poor health, most likely to be harmed
by a new virus, might actually have the most
exposure –if in fact SARS is carried by turtles.
And if it is, that might save turtles.