Increased ampicillin resistance inHaemophilus Influenzae in Northern Ireland hospitals

Twenty-nine of one hundred and ninety-three (15%) clinical isolates ofHaemophilus influenzae from Northern Ireland hospitals during 1985–1986 were found to be ampicillin resistant. This is twice the national average for the same period and a 65% increase since a similar report in Northern Ireland three years previously. Computerised monitoring of routine specimens has shown this resistance level to be maintained in 1989. Susceptibility to other antimicrobials is discussed.