Letter From “Dr. Buckaroo Banzai” Re: Pneumonia Risk–Time for Your Pneumovax?

Dear Mr. Rawles,
I think the pneumovax is a good idea. However, there are simply no data to support your statement that “pneumonia co-infections are the biggest killer associated with the Asian Avian flu.” Whether even a single victim of the current H5N1 avian flu in Asia has even developed pneumococcal pneumonia has not been reported. I doubt it. These people appear to be dying too quickly for that to be the problem. I think they are simply dying from viral pneumonia.

In 1918-1919 many flu victims died within 24-48 hours of becoming febrile. Those deaths certainly had nothing to do with pneumococcal pneumonia.

That being said, in ordinary flu epidemics, old and debilitated people do develop secondary bacterial pneumonia after their systems are further weakened by viral pneumonia with the flu. In many cases, these secondary pneumonias are caused by the pneumococcus.
So there is undoubtedly some utility in the pneumococcal vaccine. Remember, it only protects against 23 varieties of a single microorganism, the pneumococcus. As you can gather from its name, though, the pneumococcus is the poster child of bacterial pneumonia, and it certainly can and does kill.

Whether or not there will be a worldwide pandemic of H5N1 avian flu depends only on the virus — if it has become or will become easily transmissible from human to human, there will be a pandemic, because it is antigenically novel and nobody has much if any immunity to it.

In the final analysis, the scope of the pandemic also depends only on the virus — on its attack rate and case fatality rate. The attack rate means how many people in a population become infected –105 — 25% — 50% — and the case fatality rate means how many of those people die. An attack rate of about 25% appears likely for a true flu pandemic. Currently the case fatality rate in Asia appears to be about 50%, but I think that is wildly over-estimated, since only the dead and dying are being counted, and there may be many milder cases that are going undiagnosed and unreported. A case-fatality rate of 0.5% to 1% would be typical of a bad flu, and a case fatality rate of 2% or 3% was usual in most communities in 1918-1919. Anything more than that, even 5%, would be devastating. Remember that some isolated communities were more susceptible, and wiped out, in 1918-1919. All the best, – “Dr. Buckaroo Banzai”

JWR Replies: Your point is well taken, Buckaroo. When I saw references to “pneumonia co-infections” I mistakenly assumed that they were mostly pneumococcal pneumonia infections. So I went back and did some more reading. I was mistaken.  Most of the pneumonia deaths were indeed due to H5N1 viral pneumonia–which of course Pneumovax 23 won’t prevent.  But I’m glad to hear that you agree that it is a good thing to get a Pneumovax 23 inoculation, nonetheless.