The occurrence of influenza A virus on household and day care center fomites.

Objective: The goal of this study was to evaluate the prevalence of influenza A virus on surfaces in day care and home settings to better assess the potential role of fomites in the transmission of influenza.

Methods: During two and a half years, 218 fomites were tested from 14 different day care centers. Ten different fomites from bathrooms, kitchens and play areas were sampled. In addition, 92 fomites from eight different homes with children were tested over 6 months. Fourteen different household fomites from bathrooms, kitchens and living areas were sampled. Influenza A viral RNA was detected using reverse transcriptase-polymerase chain reaction.

Results: Influenza was detected on 23% of day care fomites sampled during the fall and 53% of fomites sampled during the spring. Spring and fall sample data was determined to be statistically different at the 0.05 alpha-level by Chi-square analysis P<0 and Fisher's Exact test P=0.00002. There was no statistical difference found between moist and dry fomites (Chi square P=0.13998). No influenza was detected on home fomites sampled during the summer. In contrast, influenza was detected on 59% of home fomites sampled during March.

Conclusions: Influenza A virus was detected on over 50% of the fomites tested in homes and day care centers during influenza season.