During the period 1951–58, a study has been carried out of a series of seventeen families in which more than one member developed a staphylococcal lesion.
In eleven of these families, phage typing revealed that spread of infection from person to person had occurred. Once introduced into a household, the staphylococcus demonstrated great persistence; a particular strain could cause recurrent lesions in different members for as long as 6 years. The interval between the first and subsequent infection in another member of the same family was most irregular, but was usually 2–11 months.
The patient with recurrent furunculosis appeared to be mainly responsible for dissemination of strains.
In six out of the seventeen families, although multiple infections were encountered in the household, these were not due to case-to-case spread because more than one phage type of staphylococcus was isolated.
In one family investigated, there had been a dissemination of a hospital-acquired staphylococcus to another member of the household.
No infections were encountered in which the ‘epidemic strain’ 80/81 was responsible.
I wish to express my gratitude to Dr R. E. O. Williams of the Staphylococcal Reference Laboratory, Colindale, for his assistance in this work.