As I write this the US has 279 confirmed cases and one death from H1N1/2009 in 36 states. WHO has tallied 1085 1124 cases in 21 countries with 25 deaths. There is a backlog of samples waiting for confirmation, so by the time you read this the counters will probably have rolled upward, especially as state laboratories become facile with the new primers and are able to do their own confirmation. And predicting an increasing case count is about all anyone can say with certainty at this point. What we said once about flu pandemics can be said just as appropriately for the flu virus: “If you’ve seen one flu virus, you’ve seen one flu virus.” While a likely scenario would be that sustained person to person transmission will take root in some countries outside North America, nothing is for sure with a flu virus.
One major question is whether it will move to the southern hemisphere as that half of the globe edges into their usual flu season. As WHO’s Keiji Fukuda noted at the daily press briefing, the virus appeared in the northern hemisphere at the end of the flu season and was not competing with any other circulating subtype or strain. So watching what happens in the southern hemisphere may tell us something about the relative fitnesses of H1N1/2009, seasonal H1N1, seasonal H3N2 and seasonal influenza B.
As we continue to try to sketch out the descriptive epidemiology — the spectrum of severity, who is getting sick, what is the incubation period, where is disease happening — the recommendations and judgments of CDC, WHO and local agencis will change in response. That may be confusing or unsettling but it is the only rational way to proceed. We are all learning as they go along, and in some cases, making it up as we go along.
I make the same kind of allowances for the public. We hear talk (some of it hysterical) that the public is suffering swine flu hysteria. Sometimes that talk comes from people who are clearly in denial. It is quite understandable that people become alarmed when they hear the word pandemic, not realizing it refers to the extent of disease spread, not the severity of the disease. Outside my profession, there is little acquaintance with pandemics or disease outbreaks except as fiction or popular history. With the help of some decent reporting and non-MSM sources like this one, people will learn. The public has a right to make it up as they go along, too. It’s not such a bad thing. Even if it were, it is what it is. There is no sense wringing our hands over it.
As we move forward from here, the fact that so far the virus is relatively benign — for a flu virus — we need to remember the operative word is “relatively.” 35 of the 279 cases in the US have been hospitalized, and two patients in Canada are reported severely ill. The fever, headache and joint and muscle pains characteristic of this and all influenza can be miserable and keep you out of work or school for a week or more and feeling lousy for weeks after that.
Relatively benign isn’t benign, unless your comparison is a stay in the intensive care unit or a fatal outcome.