Tyranny of the `or'
It has been only two months since the World Health Organization, for the first time ever, declared that a new disease threatened the entire planet. With lightning speed, the WHO mobilized affected nations to join hands in fending off "severe acute respiratory syndrome," each country committing to full and public disclosure. Since then, the number of front-page stories has vastly exceeded the number of people stricken, leading many--including the op-ed pages of the New York Times and the Wall Street Journal --to question whether SARS is being overblown, causing unnecessary fear, and upstaging "real" public health threats like smoking, tuberculosis, and malaria. Legitimate questions, but ones that sidestep the stark medical realities of this strange new illness. Let's consider what we know for sure, some of it newly reported last week:
SARS is quick and deadly. It starts out suddenly, like a cold or flu with a touch of "walking pneumonia." But it ends up killing 15 percent of its victims in a matter of weeks. A 15 percent fatality rate is extremely high for an acute infectious illness. Even the most wrenching flu epidemics in history rarely killed more than 1 percent of their victims. In addition to those dying from SARS, many others just barely survive, spending days in intensive care units, hooked up to artificial respirators. Like a tornado, this scourge seizes the young and healthy along with the old and infirm--whoever is unfortunate enough to cross its path. In Hong Kong, half of the elderly and up to 13 percent of younger victims died in the first wave of the epidemic, a stark indicator that we are dealing with something very scary here.
SARS is completely original. The WHO has identified the prime culprit as an entirely new strain of the coronavirus, a nanobug that in the past has been a killer in animals but not in humans. Indeed, there is reason to believe that this novel virus only recently reconfigured itself to jump from animals to humans, meaning somewhere a cluster of cows, swine, chickens, or other critters may be incubating more virus as a reservoir for future illness. Transmission among humans is not fully understood, but the virus shows up in respiratory secretions, urine, blood, and stool, suggesting multiple routes of contagion. Scarier yet, this virus is unusually hardy, surviving for hours to days on dry surfaces outside the body and not always succumbing to soap and water. (By contrast, the AIDS virus is a wimp, unable to survive outside its sanctuary in human fluids.) Sanitation and personal hygiene are important, but they are not going to defeat this potent new virus. We need a major investment now in an aggressive search for vaccines and treatment.
SARS is a mystery disease. SARS is more than a novel pathogen. It is a mystery illness still puzzling to doctors and scientists. Despite its name, SARS is apparently more than a respiratory disease. It infects the gastrointestinal tract and causes liver abnormalities. In fact, those with pre-existing hepatitis B have been shown to be especially sensitive to the illness. The serious pneumonia that defines SARS now seems to come not from the viral replication in the lung itself but rather from the body's own immune system violently reacting to this foreign invader. It's almost like friendly fire. This finding might even explain why young children with immature immune systems get a milder form of the disease. But it also creates uncertainties about treatment: It would seem that we need to suppress the immune system just enough to quiet the friendly fire, but not so much as to let the virus run wild. A tricky balancing act.
Either/or? No doubt the effort and resources needed to attack this epidemic will be sizable, and will raise concerns about siphoning money from the big-time chronic diseases we struggle with every day. Be it smoking, AIDS, or malaria, these diseases sicken and kill far more than the 7,000 ill and 500 dead seen so far with SARS. But are we facing an either/or? I don't think so. And presenting it as such is misleading to the public. These global problems are what one might call "mature diseases": We haven't controlled them, but we've come to understand what we have to do and are busily at work. SARS, by contrast, is an unknown. It could die out on its own tomorrow, but it could just as well be here to stay, a simmering part of our personal, private landscape. It could even be a repeat of 1918, when the Spanish flu, the worst respiratory epidemic of all time, started very much like SARS: A manageable but largely ignored flare-up went dormant, only to return some six months later in great fury. It killed at least as many people as the two world wars combined. Indeed, a little fear can be a good thing, especially when the foe is fierce.
This story appears in the May 19, 2003 print edition of U.S. News & World Report.