Can migrants from high-endemic countries cause new HIV outbreaks among heterosexuals in low-endemic countries?

Objectives: To investigate how the sexual behaviour of migrants originating from HIV-endemic countries affects the spread of HIV among heterosexuals in low-endemic countries. Methods: A mathematical model is developed describing the transmission of HIV in heterosexual partnerships between African migrants, Caribbean migrants, and local natives. The model accounts for infection of migrants before migration and during trips to their home country. The model is parameterized using data from the Netherlands. Results: Among new and newly imported, heterosexually acquired, infections in 2010 in the Netherlands, the individual acquiring HIV is an African in 53% of cases, a Caribbean in 26% of cases, and a Dutch native in 21% of cases. The percentage of new infections acquired outside the Netherlands is 40% among African migrants and 32% among Caribbean migrants; these are mostly acquired before migration to the Netherlands. The prevalence of HIV in the Netherlands is hardly affected by changes in risk behaviour of migrants during trips to their home country after migration. If migrants mix more with the Dutch in forming partnerships, then HIV prevalence among migrants will decrease. The more initiating antiviral therapy is delayed among migrants, the higher the resulting prevalence in their own ethnic group and among the Dutch. Conclusion: The serostatus of individuals migrating to low-prevalence countries as well as their sexual behaviour in the country of residence affect considerably the spread of HIV. Preventive measures should focus on targeted interventions, promoting safe sex practices, HIV testing, and entry to specialized HIV care among migrants. (C) 2010 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins