Oddly, though, the latest scare to have attached itself to H1N1 seems less about the virus than about the vaccine—many parents are expressing concern about its safety, and resistance to taking it seems to be building. “One of the reasons that people are resistant to the vaccine is that a lot of the flu we saw in the spring was so mild that they don’t understand that H1N1 can be fatal to healthy children,” said Dr. Alanna Levine, a spokesperson for the American Academy of Pediatrics. “The benefits of the vaccine so far outweigh the risks that it’s a no-brainer.” As Thomas Frieden recently pointed out, “It is being produced just as seasonal flu vaccine is produced … in the same factories, with the same mechanisms, with the same safety precautions.”
Memories of the swine-flu fiasco in 1976 are part of the issue here—there were fears that people may have died from side effects of a vaccine rushed through production (there was a suspected rise in cases of Guillain-Barré syndrome, a rare and sometimes fatal neurological disease). But a study conducted by the CDC in the nineties exhaustively searched for any correlation between seasonal flu vaccines and Guillain-Barré, and found none; one of the collaborators was a Tulane University doctor named Thomas A. Farley. And in the case of H1N1, “certainly, getting the infection is far more dangerous than getting the vaccine,” the health commissioner says. Palese puts it more bluntly: “If you wanna get sick, don’t take the vaccine.”
One of the biggest surprises about H1N1 is that a lot of people already seem to have some immunity to it, especially those 50 and older. Palese believes that anyone born before 1957 has in fact probably seen versions of H and N similar to what the current flu wears on its surface. “In 1957, H1N1 stopped circulating for twenty years,” he explains. “So people older than 50 saw these earlier versions of H1N1, and saw them more often. If you get bombarded many more times, you get more immunity to it.”
Over the summer, city epidemiologists surveyed the households of infected St. Francis children to see if the virus had spread to other family members. What they discovered, according to Farley, “was a steadily declining attack rate with increasing age.” Indeed, the fact that a single dose of the new H1N1 vaccines appears to be protective, Palese said, suggests that many people already have some “cross-reactive” immunity to the current strain.
So with the lessons of St. Francis, Mexico, and crowded springtime ERs firmly in mind, city health officials have embarked upon the following strategy: They plan to keep schools open. They hope to blunt the spread of the expected fall resurgence by vaccinating students. And they vow to be nimble in the face of changing information. In a bid to keep the public informed (and, one suspects, to provide an alternative to media sources of information), the Health Department is posting its surveillance data on the city’s flu portal (nyc.gov/flu), including daily reports of influenza-like illnesses in schools. If you can read a graph, you should be able to tell when, or if, the fall surge of H1N1 is taking off (check out the graph charting the spring outbreak; it looks like an Alp in the middle of Kansas).
Back in the epi shop, they’re still peering into their computer screens, still looking at the same data, still searching for signs that the virus is making a comeback in the city. “And when we don’t see anything,” Weiss said last week, “we just shake our heads and say, ‘Good, we’ve lived for another day.’”