Prevention of mother-to-child transmission of HIV (PMTCT) is the single most effective HIV prevention intervention in practice today. Nonetheless, little reliable empirical evidence exists on the behavioral effects of PMTCT. This paper documents the rapid expansion of access to PMTCT in Zambia...

Eleven percent of the Malawian population is HIV infected. Eighteen percent of sexual encounters are casual. A condom is used one quarter of the time. A choice-theoretic general equilibrium search model is constructed to analyze the Malawian epidemic. In the developed framework, people select...

The response of sexual behavior to HIV in Africa is an important input to predicting the path of the epidemic and to focusing prevention efforts. Existing estimates suggest limited behavioral response, but fail to take into account possible differences across individuals. A simple model of...

We evaluate the consequences of prosecuting HIV+ people who expose others to the risk of infection. We show that the effect of aggressive prosecutions on the spread of HIV is a priori ambiguous. Aggressive prosecutions tax risky behavior and thus deter unsafe sex and limit the number of sexual...

Recent breakthroughs in the treatment of HIV have coincided with an increase in infection rates and an eventual slowing of reductions in HIV mortality. These trends may be causally related, if treatment improves the health and functional status of HIV+ individuals and allows them to engage in...

I use a randomized experiment to test whether information can change sexual behavior among teenagers in Kenya. Providing information on the relative risk of HIV infection by partner's age led to a 28% decrease in teen pregnancy, an objective proxy for the incidence of unprotected sex....