Revisiting adverse reactions to vaccines: A critical appraisal of Autoimmune Syndrome Induced by Adjuvants (ASIA)

•Growing body of research about Autoimmune Syndrome Induced by Adjuvants (ASIA).•ASIA criteria lack definition of adjuvant dose and limits on temporal association.•Current lack of in-depth epidemiological data examining significance of rare events.•No robust animal model of ASIA syndrome currently defined.

In 2011 Shoenfeld and Agmon-Levin proposed a new syndrome as a way of grouping together a range of emerging autoimmune diseases with possible adjuvant-associated causes, Autoimmune/Auto-inflammatory Syndrome Induced by Adjuvants (ASIA). At present, there is no evidence to suggest that ASIA syndrome is a viable explanation for unusual autoimmune diseases. Since the initial paper, over 80 publications have discussed ASIA. This systematic review examines the research that has been done to investigate whether ASIA is a broad umbrella term with little clinical significance, or whether there is some underlying mechanism which could be utilised to reduce the occurrence of adjuvant mediated disease. Twenty-seven animal, epidemiological and case studies were reviewed. Unfortunately, a robust animal model of ASIA using biologically relevant doses of adjuvants has yet to be defined. It is also apparent that the broadness of the current ASIA criteria lack stringency and, as a result, very few cases of autoimmune disease could be excluded from a diagnosis of ASIA. The current studies involving human cases are so diverse, in both external stimuli and in resulting conditions, that there is currently a lack of reproducible evidence for any consistent relationship between adjuvant and autoimmune condition. The addition of a mandatory criterion requiring temporal association and clinically relevant adjuvant dose would allow better definition of what constitutes a diagnosis of ASIA.