Aluminium-containing vaccines and macrophagic
Aluminium-containing vaccines and macrophagic myofasciitis. In France, biopsies of deltoid muscle from patients with avariety of complaints have revealed, in a few cases, the presence of a minute inflammatory focus of macrophages with associated necrosis, called macrophagic myofasciitis (MMF). These localized lesions have been shown to contain aluminium salts. Since the location of the lesions in the deltoid muscle coincides with the usual injection site for vaccines, it would appear that these microscopic lesions are related to immunization. In addition, scientists from the Groupe d’études et de recherche sur les maladies musculaires acquises et dysimmunitaires (GERMMAD) have suggested that vaccination and localized MMF lesions may be associated with a multi-system disorder. However, it remains possible that the finding is only coincidental. WHO initiated a broad consultation on the issue in September 1992, on the advice of GACVS, with experts, GERMMAD scientists, and interested pharmaceutical companies. It was important to determine why macrophagic inflammation persists in a small number of subjects following immunization, and whether this histological lesion may or may not be responsible for generalized symptoms in some patients. These questions can be resolved only by epidemiological studies comparing individuals with and without the lesion. In 1999, WHO recommended that a study be undertaken to establish whether or not there is an association between local MMF lesions and any generalized illness. This study is now in progress.
Preliminary results of animal studies conducted in monkeys and rats to examine the long-term persistence of aluminium and histopathological changes at the vaccine injection site, as well as comparative studies of macrophagic function in healthy subjects and patients with MMF, further support the idea that MMF may represent a simple marker of vaccination with long-term persistence of aluminium at the injection site and minute local inflammatory response to it, without other symptoms or consequences.
The most recent evidence suggests that there is no reason to conclude that administration of aluminium-containing vaccines poses a health risk or to change current vaccination practice. The issue will be further considered when the results of the ongoing epidemiological study become available.