Of birds and men
A deadly virus is brewing in Asia. Could this be the next killer pandemic?
These sorts of advance preparations cost serious money--an estimated $100 million to build a new vaccine plant, for instance. Yet the call to arms comes at a time when perpetually lean local health departments have exhausted a few years' worth of federal bioterrorism funding that came their way after 9/11. State budgets are hurting, and the Bush administration proposes cutting funding for the CDC, which is leading much of the nation's antipandemic efforts, by $500 million.
Given that funds are scarce and much remains to be done, it may seem odd to hear health officials say that the United States should invest in the health of Asian chickens. The United States has already banned imports of poultry from countries with H5N1 outbreaks, to keep people from contracting the virus by eating infected birds, which may have happened in Asia. Earlier this month, inspectors in Cleveland and Columbus, Ohio, seized crates of boneless chicken feet that had been smuggled in from Thailand labeled as jellyfish. The shipments were part of 9,000 pounds of chicken feet that were distributed in 11 states.
Scientists also believe that if the rampant levels of H5N1 infection in Asian poultry could be reduced, it would also reduce the odds of the virus infecting people or mutating into a more lethal form. Flu viruses and other scourges often arise in animals, then infect humans. SARS, which killed 800 people in 2003, jumped from civet cats in live markets in southern China. H5N1 has already proved its versatility, infecting ducks, tigers, leopards, and humans. "We can talk about vaccine development, strength of surveillance, stocking of Tamiflu, and all that, but in the end the reduction of pandemic risk will be decided by the number of chickens infected in Asia," says WHO's Stohr.
Public-health officials in many countries are also closely watching the number of new human bird flu cases reported in Asia, hoping to get an early warning when a contagious mutation starts spreading. Although the conventional wisdom is that a pandemic can't be stopped, Thailand is starting to explore the notion of trying to contain an H5N1 pandemic, according to Scott Dowell, a CDC epidemiologist who heads the center's international office in Thailand. Last September, after a Thai woman contracted H5N1 from her daughter in the first documented case of human-to-human transmission, the Thai government launched a door-to-door search for new cases with almost 1 million volunteers. No other cases were found. But many researchers feel that Vietnam has been less than forthcoming about its H5N1 cases, and there has been an almost total news blackout in Laos and Cambodia, making it impossible to combat the spread of H5N1 there. The situation is reminiscent of SARS, when the Chinese government suppressed early reports of outbreaks until the virus had escaped its borders. H5N1 also might be getting harder to track. In at least one case, a child without respiratory symptoms who died from what appeared to be encephalitis was later found to be infected with H5N1. And recently two family members of H5N1 victims in Vietnam tested positive for the virus, despite the fact that they hadn't fallen ill.