Between 1964 and 1966 comparative studies were carried out in Aberdeen, Scotland, and in village settlements in Fiji on the clinico-epidemiological features of molluscum contagiosum. In Aberdeen there was a positive correlation between this disease and attendance of patients at public swimming baths. The preponderance of male patients in Aberdeen was attributed to their more frequent indulgence in swimming. Household spread of the condition was rare in Aberdeen but common in Fiji. Lesions frequently occurred unilaterally or were situated on opposing skin surfaces. They were mainly central in distribution in Aberdeen, the axilla being a site of predilection. In Fijians, peripheral lesions were fairly common though palms and soles were not affected. Peak age incidence in Aberdeen was 10–12 years, contrasting with a peak at 2–3 years in Fiji. Opportunity for contagious exposure appeared to be the main factor determining transmission of molluscum contagiosum between hosts, this opportunity occurring frequently and early in life in Fiji but only under special circumstances and later in childhood in Aberdeen. However, the age distributions in the two populations suggested the possible operation of immunological as well as environmental factors in determining the overall pattern of disease in the community.

We should like to express our thanks to the following people whose support and co-operation made this joint study possible: Dr K. J. Gilchrist, Principal of the Fiji School of Medicine; Prof J. A. R. Miles, Department of Microbiology, University of Otago; Dr C. H. Gurd, Director of Medical Services, Fiji; and Prof. A. Macdonald, Department of Bacteriology, University of Aberdeen. We are indebted to Dr T. E. Anderson and Dr R. A. Main of the Aberdeen Royal Infirmary for referring patients, to Mr W. Hodgkiss of the Torry Research Station, Aberdeen for carrying out the electron microscopy and to Dr Peter Bennett, Nuffield Foundation Scholar in Tropical Medicine from Aberdeen in 1962, who brought to the attention of the Aberdeen workers the prevalence of molluscum contagiosum in Fiji. Part of the work was supported by a grant to R. Postlethwaite from the British Empire Cancer Campaign for Research. Mr (now Dr) Ian Simpson and Miss Helen Adam were supported by Nuffield Foundation Scholarships in Tropical Medicine, and Dr J. A. Watt by a Garden Research Fellowship from the University of Aberdeen.