Report of an outbreak: nursing home architecture and influenza-A attack rates.

A newly built nursing home was analysed to establish why there had been a significantly lower attack rate in this building during a type A influenza epidemic. Measurements were taken of the number of respiratory illnesses and influenza cultures in consenting symptomatic residents, and of building characteristics. Of the four buildings in the home, Building A had significantly fewer culture-confirmed cases than the other buildings. Building A's ventilation system was unique, it had more public space per resident, and did not have office space serving the whole complex. Concludes that the architecural design may have an influence on the attack rate in nursing homes.