Insights from twin Sudden Infant Death Syndrome studies could reveal an aetiopathogenetic pathway to sudden infant death through immunopathology

Twins represent an interesting and unique resource to help unravel the mystery of sudden Infant death syndrome (SIDS). This is because of some outstanding coincidental findings: these include the increased susceptibility to both SIDS and infectious diseases. Susceptibility resides in their inadequate, immature immune system and contributing factors associated with prematurity, such as not benefiting from the protective advantages of transplacental maternal antibodies and not usually receiving the protection of colostrum and/or breast milk. The review examines infection and pseudo-infection (i.e., vaccination) in the context of a disadvantaged, immature infant immune system and how this could contribute as a cause of SIDS through the effects of immune perturbation via hyperimmunization. In this respect, the potential adverse effects of exposure to multitudinous vaccine target antigens in the first year of life is reviewed.