Cot deaths in Canterbury (NZ): lack of association with respiratory virus patterns.

This study was done to see whether any association between SIDS and respiratory viruses might be more obvious in Canterbury where the cot death rate is so high (about seven per thousand live births). The numbers of common respiratory virus identifications for the eight year period July 1981 to June 1989 were analysed for associations with cot death. The identifications were from inpatients at the Christchurch Public Hospital and other community sources in Canterbury. Weak associations were found with respiratory syncytial virus (r = 0.3), influenza A (r = 0.3) and influenza B (r = 0.2). However, the associations are overwhelmed by the effect of the month of the year. A high rate of respiratory virus infection cannot be invoked as the explanation for our high SIDS rate.