Trends in HIV incidence in homosexual men in developed countries.

OBJECTIVES To describe trends in HIV notifications and in other measures of HIV incidence in homosexual men in developed countries. METHODS A literature search was conducted using PubMed. In addition to the peer-reviewed literature, data on HIV surveillance trends were sought by searching websites of surveillance authorities in developed countries. RESULTS The availability of long-term HIV surveillance data varied considerably. However, in almost all jurisdictions in which such data were available, notifications of new HIV diagnoses among homosexual men have increased, mostly since the late 1990s. The magnitude of this increase varied, but was more than 50% in many countries. There were much fewer data available on trends in direct measures of HIV incidence in homosexual men, and increases in HIV testing rates may have contributed to the increases in HIV diagnoses in many countries. However, since the late 1990s, several clinic- and community-based cohort studies in Europe and North America reported increasing incidence. CONCLUSION There were increases in HIV notifications in homosexual men in almost all developed countries, starting in the late 1990s and continuing to 2006. Although increases in HIV testing probably contributed to the increases in some settings, limited cohort data do support the existence of a true increase in HIV incidence in European and North American countries. Improved monitoring of HIV incidence in homosexual men at the population level is required to allow more timely assessment of the drivers underlying such trends.