Sunday, April 11, 2010

Lessons From the H1N1 Flu Hype

The flu has vanished from the public agenda. But flu, mainly from the H1N1 virus, is still happening. Based on my own informal measures, cases have fallen off by only about half from the lows of the last week of December. It’s important to note that the rate of H1N1 cases never bounced back from the steep drop-off that occurred that week with all the schools closed. To my mind, that nearly proves that we could stop worrying about flu epidemics if we would just do more aggressive cleaning of hand-contact surfaces in schools. Yes, the additional school cleaning staff that would be required could cost $5 billion a year across the United States, but that is nothing compared to the productivity that would be gained by having fewer people miss work (or school, for that matter) because of the flu.

Flu season is not considered over at the beginning of April, but it is not too soon to say that it was one of the mildest flu seasons in recent memory. Partly this was because people took more precautions after hearing the flu hype. I’m referring specifically to cleaning and social distancing — there is no evidence that the H1N1 vaccine arrived in time to have any effect on the spread of flu in the United States. It would have been needed in June to be useful, and by the time the vaccine had seen minimal testing on a few hundred healthy people, in September, the H1N1 pandemic had already passed its peak. And that is surely the main reason the flu season was so mild. Most people had already been infected with the dominant flu strain of the season, H1N1, during the summer.

The first lesson from the H1N1 pandemic, obviously, is this: Don’t believe the hype. Scientists hardly know anything about pandemics. When World Health Organization officials start talking about pandemic projections, the predictions are based more on politics than on science.

It’s not too soon to say that the H1N1 virus never went worldwide. Cases were found on every continent, but not in every country, and in only a small fraction of communities. I believe it must be recognized that something about modern health and hygiene creates resistance to the spread of a virus, making it impossible for a new virus to spread the way viruses did in centuries past.

The rush to create and distribute the H1N1 vaccine was a colossal failure, and not from lack of effort. In this failed mission, we may have been led astray by science fiction. In several Star Trek episodes, the vaccine or antidote arrives just in time to save the crew, or the planet. But apparently thousands of the best minds in medical technology working together can’t match the results of one Julian Bashir.

What did we get for an H1N1 vaccine? Estimates are that the vaccine that was delivered in quantity in October was about 70 percent effective in healthy adults; we are lucky if it was 45 percent effective in the elderly and ill populations that most need the protection of the vaccine. The FDA waived some standards of proper testing and good manufacturing practices to get the vaccine out quickly, and that resulted in a product far more variable than we expect from a vaccine. One batch of the rushed vaccine was recalled for ineffectiveness, but it’s highly likely that other doses were problematic in various ways that weren’t detected. And to add insult to injury, we know in retrospect, from the epidemiological record, that we would have needed the vaccine in June for it to stop the epidemic in the United States. It arrived in October, 100 days too late to matter. With that as a track record, we probably shouldn’t even try to rush the vaccine next time. To prevent the pandemic from occurring, scientists would have needed to go from virus identification to vaccine manufacture in a matter of days. That’s a risky gamble when they do it on Star Trek; it would be absolutely terrifying if health authorities were to attempt it in reality.

I have one other thought on the flu vaccine. We just had an extraordinarily mild flu season after an extraordinary spike in flu exposure that occurred in August and spilled over into September. Perhaps that is a sign that we ought to consider distributing flu vaccines in August and September, rather than the traditional November and December. This recent experience provides a reason to imagine that vaccines would be more effective in late summer than in late fall.

Finally, there is the effect of the H1N1 flu scare on the economy. Local governments and hospitals were extraordinarily tight with their budgets late last year because of the specter of the costs that could be associated with a massive flu outbreak. It turns out that was a good move even though the flu never materialized. Hospitals, for the most part, can breathe a little easier now, but they cannot exactly begin rehiring the staff they laid off. Rather, the current situation is probably just a respite before the next round of layoffs. Most local governments are running at a deficit because of the weak economy, in spite of budgets that were supposed to have a bit of slack in them. They will have to cut back further this year, and probably again next year.