The committee made several important points:
- There had been no decrease in invasive pneumococcal disease since routine vaccinations were begun in 2003 [this refers to pneumonia, meningitis and sepsis--Nass]
- Vaccine effectiveness is poor in the over-65 age group
- Revaccination did not help, and may have led to a poorer response due to "immune hyporesponsiveness"
Being an observer of the rush to add vaccines to the list of approved medications before there is adequate safety and efficacy data, and then institute their widespread use, this recommendation adds a breath of fresh air to the conversation on vaccines' net benefits.
To my knowledge, this is the first time a standard vaccine program will be ended in the UK. The Hepatitis B vaccine program ended in France in the mid 1990s after half the population was vaccinated. The Rotavirus vaccine program ended in the US in 1999, but restarted recently with another version of the vaccine. The 1976 swine flu program ended precipitously. Each vaccine program ended due to unacceptably high rates of serious adverse reactions. I am not sure there are data on how effective these programs were at preventing disease, though swine flu never became an epidemic in 1976, never spread beyond Fort Dix, and the vaccine program was entirely unnecessary.
Acknowledgment that revaccination may actually increase the risk of pneumococcal disease is welcome. Several animal vaccines in widespread use were found to increase the disease they were meant to prevent, and I have wondered whether any human vaccines may have done the same thing.
Evidence from Hong Kong and Canada that being vaccinated for seasonal influenza in 2008 was associated with twice the risk of becoming ill with H1N1 swine influnza in 2009-10 suggests that the same problem may be associated with human vaccines.
Using antibody levels (serology) to predict vaccine efficacy against disease, as is often done today, instead of looking for cases of disease prevented, both overstakes vaccine efficacy and masks any possible effect on disease promotion by a vaccine. University of Michigan researchers Monto, Petrie et al. have just published a nice piece on how influenza efficacy is overstated by serologic tests.
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