The protective effect of immunisation against diphtheria, pertussis and tetanus (DPT) in relation to sudden infant death syndrome

Abstract

Epidemiological evidence indicates infants immunised against diphtheria, pertussis and tetanus (DPT) are at decreased risk of sudden infant death syndrome (SIDS). Asymptomatic whooping cough and pyrogenic toxins of Staphylococcus aureus have been implicated in the aetiology of SIDS. The objectives of the present study were: (1) to determine if the DPT vaccine induced antibodies cross-reactive with the staphylococcal toxins; (2) to determine if antibodies to the pertussis toxin (PT) and the staphylococcal toxins were present in the sera of women during late pregnancy; (3) to examine the effects of infant immunisation on levels of antibodies to PT and the staphylococcal toxins; (4) to assess the effects of changes in immunisation schedules in the UK on the incidence and age distribution of SIDS. Enzyme-linked immunosorbent assays (ELISA) were used to measure binding of rabbit or human IgG to the DPT vaccine, PT, toxic shock syndrome toxin-1 (TSST-1) and staphylococcal enterotoxins A (SEA), B (SEB) and C (SEC). Neutralisation activity of anti-DPT serum was assessed by a bioassay for induction of nitric oxide from human monocytes by the staphylococcal toxins. Anti-DPT serum bound to the DPT vaccine, PT and each of the staphylococcal toxins. It also reduced the ability of the four toxins to induce nitric oxide from monocytes. In pregnant women, levels of IgG to PT, SEC and TSST-1 decreased significantly in relation to increasing weeks of gestation while antibodies to SEA and SEB increased. In infants' sera there were significant correlations between levels of IgG bound to DPT and IgG bound to PT, TSST-1 and SEC but not SEA or SEB. Antibody levels to the toxins in infants declined with age; sera from infants 92 months of age had higher levels of IgG bound to the toxins than those older than 2 months. This pattern was observed for infants whose immunisation schedules began at 2 months of age or 3 months of age. The decrease in IgG bound to the toxins was, however, less for those immunised at 2 months. The decrease in SIDS deaths after the change in immunisation schedules was greatest in the 4^6-month age range. While DPT immunisation might prevent some unexplained infant deaths due to asymptomatic whooping cough, these data indicate that immunisation with DPT also induces antibodies cross-reactive with pyrogenic staphylococcal toxins implicated in many cases of SIDS. Passive immunisation of infants who 0928-8244 / 99 / $20.00 ß 1999 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved. PII: S 0 9 2 8 -8 2 4 4 ( 9 9 ) 0 0 0 8 7 -5

Toxigenic bacteria and sudden infant death syndrome (SIDS): nasopharyngeal flora during the first year of life

“…These toxins have been identified among SIDS infants in Britain, France and Australia. In our local population there was a decline in antibodies to TSST and SEC 1 during late pregnancy but not SEA or SEB [53]. Methods to reduce colonisation by S. aureus or methods to boost passive or active immunity to these toxins during the early months of life might further reduce the numbers of SIDS deaths.…”

Sudden infant death syndrome (SIDS) shortly after hexavalent vaccination: another pathology in suspected SIDS?

“…Many studies have shown that vaccines are not associated with an increased risk of SIDS [8,24]. Some studies have even shown a reduced risk of SIDS associated with vaccinations [5]. Despite this, from time to time this controversy is reopened [3].…”

Peptide Sharing between Bordetella Pertussis Proteome and Human Sudden Death Proteins: A Hypothesis for a Causal Link

“…As with inflammatory responses to sepsis, cytokines, induced by bacterial toxins, might cause physiological changes leading to death [20,21]. In support of this hypothesis, Essery et al observed that anti-DPT immunization induces antibodies that cross-react with pyrogenic staphylococcal toxins, which have been implicated in several cases of SD [22]. Hence, these authors suggested that part of the protective effect of DPT vaccination in relation to SD may be due to the induction of cross-reacting antibodies that are capable of reducing the effects induced by the pyrogenic staphylococcal toxins.…”