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.
