Baffling Resistance to SARS
Seeking clues in AIDS patients
By Laurie Garrett
Newsday, Staff Correspondent
April 29, 2003, 6:42 PM EDT
Beijing -- A small but potentially intriguing clue has emerged in the SARS
fight, even as China's epidemic continues to spiral.
>From the Beijing perspective, the epidemic couldn't look worse. The city
added 152 cases Tuesday. More residential complexes were placed under
quarantine, bringing the total of sequestered residents to more than 8,000.
Throughout the rest of the nation, frightened citizens erected barricades and
screening centers to bar travel by people from Beijing.
Amid the mounting toll, Newsday learned that a select population in
Guangzhou, the southern Chinese city where the epidemic apparently began in
November, appears to have resisted infection. At the peak of the outbreak
there, in January and February, patients with the then-mystery illness were
kept on the second floor of one hospital. The floor was already in use as an
Guangzhou authorities divided the floor of People's Hospital No. 8 in half,
putting SARS patients on one side of the elevator bank, and AIDS patients on
the other. Health care workers walked back and forth between the two sides of
the floor, and some of those doctors and nurses contracted SARS.
Yet not one of the several dozen AIDS patients or their visitors, some of
whom were also HIV positive, developed the disease.
"I am wondering why there was no SARS virus co-infection in the AIDS cases,"
Dr. Zhang Fujie, director of AIDS treatment and care for China, said Tuesday
in an interview. "We are exchanging information with Hong Kong on this. We
will continue to try to understand that."
Dr. Cheng Feng of the China/UK HIV/AIDS Project said he, too, was aware of
the phenomenon. He wondered whether the drugs the AIDS patients were
receiving for HIV control might be blocking a SARS infection. A similar
notion was mentioned by Dr. Yuen Kowk-yung of the University of Hong Kong.
With New York's Dr. David Ho, of the Aaron Diamond AIDS Research Laboratory,
Yuen is exploring the AIDS apothecary for an effective SARS treatment.
But the puzzle may be deeper. That's because the most effective anti-HIV
drugs -- a class called protease inhibitors -- are not available to Guangzhou
patients, according to an HIV outpatient and activist who asked to be
identified only as Thomas. Few Chinese patients have access to any but the
cheapest, least effective of the anti-HIV drugs, Thomas said, which target a
chemical that is not even present on the coronavirus that's been identified
as causing SARS.
"I went in there to visit HIV patients, my friends," Thomas said. "We were
all asked to wear masks, special clothes and latex gloves. But the HIV
patients on the ward said they didn't like to wear masks, and they refused.
But they all looked healthy."
SARS so far has presented scientists with a number of perplexing aspects.
Some scientists speculate that the virus doesn't actually kill human cells --
that the immune system's overreaction actually precipitates the destruction
of cells of the lung and other parts of the body, precipitating the acute
pneumonia that is the disease' hallmark. In theory, they say, death may be
the result of an aberrant or overly sensitive immune response. If that is
proved correct, it's possible that HIV patients may actually be at lower risk
for SARS precisely because they lack strong immune responses.
This is only speculation, of course, but the notion is garnering interest
among physicians here. An added bit of evidence supports the theory: The most
effective SARS treatment so far is steroids -- agents that stifle the immune
Otherwise, there was little cause for optimism in China Tuesday. Beijing's
toll is swiftly approaching, in just three weeks, the cumulative total seen
in Guangdong, the province that includes Guangzhou, over a six-month period:
Beijing now has 1,347 reported cases; Guangdong has seen 1,399. Nationwide,
the total reached 3,303.
The atmosphere here Tuesday was eerie, as streets in many districts were
nearly empty, most small businesses and restaurants were closed and apartment
complexes throughout the city were under quarantine. In the Cao Jun Miao
neighborhood, a squadron of police cordoned off entry to a residential
complex, declining to confirm whether SARS cases were inside. Quarantine
notices were posted, and people decked out in masks, gowns and gloves stacked
boxes of food just outside the entry of the building, expecting residents to
claim the goods.
At Beijing's main train station, a modest crowd of travelers intent on
leaving he city was willing to endure such actions in distant provinces.
"We are leaving Beijing because I am scared of SARS," a nine-month pregnant
woman who gave her name only as Mrs. Wang said as she looked after her
family's luggage outside the station.
"We go home to Anhui province because my wife is nervous, and she is
pregnant," Her husband said. "We know when we get there we will be
quarantined for twelve days."
Young Liu Chao, his punk haircut in dyed stripes, slumped on a train station
bench. He was on his way to distant Dalian, mainly because his parents were
worried about his safety amid an epidemic, but admitted, "I'm a little
worried I might be quarantined when I get there."
The World Health Organization's Beijing office expressed concern Tuesday
about the SARS situation in China's poor provinces. The tolls in those areas
rose, with Shanxi reporting 266 cases and Inner Mongolia, 120.
The WHO praised Asia's leaders Tuesday, however, for reaching agreements in
an emergency meeting in Kuala Lumpur on SARS-related travel restrictions.