Because of its close links to behaviour, the epidemiology of sexually transmitted infections (STIs) involves forays into social science research. One of the most vexing problems has been defining the relation between ethnicity and STI risk. Defining these associations, even when methodologically carefully performed, is problematic because of the historical context of discrimination in both the United States and Europe. However, not dealing with these issues in a forthright manner may have profound public health consequences.

Population based cross sectional studies in the United States have demonstrated increased rates of gonorrhoea, chlamydia,¹ and genital herpes² in African-Americans. The herpes studies are particularly instructive because they were based on a national sample—and the differences persist when controlled for socioeconomic status and other demographic variables. The differences are also stable over time. In the United Kingdom, studies have shown that gonorrhoea rates in Leeds,³ Birmingham,⁴ and south London⁵ and chlamydia rates in Coventry⁶ and Birmingham⁴ were substantially higher in black residents, again after controlling for socioeconomic status, and in an environment (in contrast with the United States) where there is universal access to free health care.

Commenting on the papers by Low et al⁵ and Lacey et al,³ Raj Bhopal⁷ cautioned us to be prudent in using ethnicity data because of the historical propensity to marginalise and discriminate against minorities, but reminded us not to shirk from our responsibilities in protecting …