Distribution and importance of the Pharoah's ant Monomorium pharaonis (L) in National Health Service Hospitals in England

An assessment of the incidence of Pharaoh's ant infestations in NHS hospitals in England was made by analysing the answers to a questionnaire completed by domestic services and other hospital staff trained to recognize this insect. About half of all hospitals in England were covered by the survey and over 10 per cent were reported as infested. When the hospitals were allocated to their Health Districts, nearly half of those covered by the survey contained at least one infested hospital. The incidence or distribution of these ants could not be related to climatic or demographic factors but London and its suburbs were particularly heavily infested.