Introduction:
On 2 June, 1992, the Laboratory Centre for Disease Control (LCDC), Health Protection Branch, Department of National Health and Welfare, asked Dr. Gilles Delage to set up an independent working group to evaluate the evidence linking hepatitis B vaccination with the chronic fatigue syndrome (CFS). Dr. Delage agreed to act as the chairman of the group, and experts were recruited in the following fields: clinical investigation of patients with CFS, clinical studies of hepatitis B vaccination in health care workers, epidemiology and study design, public health programs pertaining to hepatitis B vaccination, and immunology of vaccine response. The working group held a 1-day meeting on 2 November, 1992. It reviewed in detail the data collected by LCDC on 30 self-reported cases of CFS (meeting a standard case definition) alleged to be secondary to hepatitis B vaccination. The working group then reviewed data made available by some of its members. After a lengthy discussion, all members of the working group agreed that there is no evidence of a cause-effect relationship between hepatitis B vaccination and CFS. This report outlines the reasons why the group arrived at this conclusion.
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Source: Report of the working group on the possible relationship between hepatitis B vaccination and the chronic fatigue syndrome. CMAJ. 1993 Aug 1;149(3):314-9. [Article in English, French] http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1485526/