Monday, July 12, 2010

Gaming the Evidence: Evaluating adverse events post-vaccination/ BMJ rapid response

A letter to the BMJ questions the rationale for using certain new vaccines in India that fail to "result in significant reduction in disease burden" when older, cheaper and proven vaccines costing less than US $1.00 total per child are not being given to half the children in India.

The letter also unmasks a scam in the assessment of child deaths post-vaccination by a WHO expert panel.  The "Expert Panel was formed by the WHO Department of Immunization, Vaccines and Biologicals to provide expert advice on the potential causal association between selected serious AEFI (adverse event) cases reported in Sri Lanka in 2008 and the vaccines received by the affected infants." *

The expert panel did not perform its assessment away from the watchful eye of WHO.  "WHO/IVB (WHO Department of Immunization, Vaccines and Biologicals) staff served as secretariat to the Expert Panel to facilitate the review," according to the WHO Ad Hoc Expert Panel Report. *

WHO has standard criteria for making a causality assessment of post-vaccination adverse events.   The criteria are routinely used internationally.  However, in this case WHO's experts "deleted the categories Probable and Possible from the standard classification. All adverse events which could not be classified as Very likely/Certain were classified as Unlikely."

With this simple manuever, since they could not say causality was certain, the panel gave the impression that the vaccine was unlikely to be related to any deaths.  No explanation was given for why the WHO criteria were not used in this WHO study. 

WHO. Report of an ad-hoc WHO expert panel to review reports of serious AEFI following administration of pentavalent and other vaccines in Sri Lanka 2008 -- available at:

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