To put those last numbers in perspective, there are currently 1,870 ICU beds in New York City hospitals, according to associate health commissioner Geoffrey Cowley, and the average daily occupancy is about 90 percent. “In an emergency,” Cowley says, “hospitals would free up ICU beds by triaging some patients to regular ones.” Even with a “realistic increase in cases,” Palese argues, “we cannot handle it as a city—or as a country, for that matter.”
But by the summer, city planners knew they weren’t dealing with that kind of virus. They were feeling relatively confident that the new H1N1 was, in Farley’s words, “much less severe” than the seasonal flu. Indeed, within two weeks of the St. Francis outbreak, one word began to creep into the medical conversation: “mild.” With some important exceptions—young children with health problems (asthma, or neurological disorders like cerebral palsy), pregnant women, and older adults with preexisting health problems like heart disease or diabetes—the new H1N1 seemed to cause primarily mild disease.
Yes, there were 54 fatalities in New York City as of this summer, but that was out of an estimated 750,000 to 1 million infected people. During an average flu season, by contrast, about 1,100 New Yorkers die of seasonal influenza. Deputy Mayor Gibbs says the city has planned for “the most likely scenario, where it comes back, is widespread, and remains mild.” Under that scenario, this fall’s advice will sound pretty familiar: wash your hands, cover your sneezes, and if you get sick, stay home until you feel better. Only for a small subset of people—pregnant women, children under 2, and people with chronic health problems—are the rules a little different: If you start to feel seriously ill, seek medical advice as rapidly as possible, since antiviral medications like Tamiflu work best when administered early. And since children seem both to drive the outbreaks and to get sick more than other age groups, the city decided to provide free H1N1 vaccine for all students.
In the end, St. Francis turned out to be an aberration. “No other school in the city replicated the kind of numbers we saw there,” says Gibbs with a shrug. “I don’t know—luck of the draw? But that was our opening moment, right? St. Francis, simultaneous with what we were hearing out of Mexico, and nobody knowing how virulent it was.”
Now they do. In order to become more virulent, according to Palese, the virus would need, at minimum, to acquire one of the genes that seems to have conferred devastating virulence on the 1918, 1957, and 1968 pandemic strains. Known as PB1-F2, it is not active in the new H1N1 flu strain, and acquiring it would be an exceedingly rare (though not impossible) event. Without getting into a lot of genetic mumbo jumbo, the currently circulating strain could acquire the more lethal form of this gene in one of two ways. One would be to pick up three separate, specific, and simultaneous mutations in a particular area of the virus’s genetic instructions to switch on PB1-F2; the odds of two such mutations occurring together are, says Palese, about one in 10 billion, the odds of all three, one in a quadrillion.
The other way would be for the virus to obtain the lethal version of the PB1 gene in an event known as “reassortment.” This happens when two different flu viruses occupy the same cell at the same time and swap (or “reassort”) their genes. “Which is not that difficult,” Palese notes. “It could be in a human, birds, pigs, reindeer, ducks, horses, whales, turkeys.”
But even these rare reassortment events come with cumbersome genetic baggage. It would be, Palese says, “like taking the engine of a Lamborghini—great sound, 500 horsepower!—and putting it into a Volkswagen. If you put it into the swine virus, it may not work.” This is why Palese sometimes refers to the current H1N1 outbreak as “a 0.5 pandemic.” Meaning? “It is not a real pandemic,” he says.
Where does that leave us? With no evidence of a fall surge locally, so far, and a lot of vaccine on the way—although not as much initially as city officials expected. The city placed an order with the CDC for its first batch of vaccine last week and was told it would arrive in a matter of days. A month ago, officials thought they’d receive approximately 1.5 million doses in mid-October; late last week, Farley learned it would be less than 50,000, although much more is on the way. The first batch will be live vaccine in the form of the nasal spray FluMist, which means that pregnant women, children under 2, people over age 50, and people with chronic health conditions cannot be vaccinated with it. “So it will have limited utility,” Farley says. “It’ll be primarily useful for children.” Other formulations of the vaccine, like shots, are expected within weeks.