Stefano M. Bertozzi

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BACKGROUND Economic theory and limited empirical data suggest that costs per unit of HIV prevention program output (unit costs) will initially decrease as small programs expand. Unit costs may then reach a nadir and start to increase if expansion continues beyond the economically optimal size. Information on the relationship between scale and unit costs is(More)
BACKGROUND In Mexico, the lifetime risk of dying from maternal causes is 1 in 370 compared to 1 in 2,500 in the U.S. Although national efforts have been made to improve maternal services in the last decade, it is unclear if Millennium Development Goal 5--to reduce maternal mortality by three-quarters by 2015--will be met. METHODOLOGY/PRINCIPAL FINDINGS We(More)
1 Current calls to action for HIV prevention programming stress the need for more strategic, combination prevention strategies along with evaluation components to measure effectively the impacts of such efforts. The Avahan project, implemented since 2003, is one example of a combination prevention programme for a concentrated epidemic that offers a clear(More)
BACKGROUND In the spring of 2009, an outbreak of severe pneumonia was reported in conjunction with the concurrent isolation of a novel swine-origin influenza A (H1N1) virus (S-OIV), widely known as swine flu, in Mexico. Influenza A (H1N1) subtype viruses have rarely predominated since the 1957 pandemic. The analysis of epidemic pneumonia in the absence of(More)
We have entered a new era in HIV prevention whereby priorities have expanded from biomedical discovery to include implementation, effectiveness, and the effect of combination prevention at the population level. However, gaps in knowledge and implementation challenges remain. In this Review we analyse trends in the rapidly changing landscape of HIV(More)
BACKGROUND Heterosexual contact is the most common mode of HIV transmission in India that is largely linked to sex work. We assessed the non-use of condoms in sex work and with regular sex partners by female sex workers (FSWs), and identified its associations that could assist in planning HIV prevention programmes. METHODS Detailed documentation of(More)
BACKGROUND There is strong evidence showing that male circumcision (MC) reduces HIV infection and other sexually transmitted infections (STIs). In Rwanda, where adult HIV prevalence is 3%, MC is not a traditional practice. The Rwanda National AIDS Commission modelled cost and effects of MC at different ages to inform policy and programmatic decisions in(More)
BACKGROUND We explore vaccination strategies against pandemic influenza in Mexico using an age-structured transmission model calibrated against local epidemiological data from the Spring 2009 A(H1N1) pandemic. METHODS AND FINDINGS In the context of limited vaccine supplies, we evaluate age-targeted allocation strategies that either prioritize youngest(More)
Even after 25 years of experience, HIV prevention programming remains largely deficient. We identify four areas that managers of national HIV prevention programmes should reassess and hence refocus their efforts-improvement of targeting, selection, and delivery of prevention interventions, and optimisation of funding. Although each area is not wholly(More)
OBJECTIVE To assess effects on condom use and other sexual behaviour of an HIV prevention programme at school that promotes the use of condoms with and without emergency contraception. DESIGN Cluster randomised controlled trial. SETTING 40 public high schools in the state of Morelos, Mexico. PARTICIPANTS 10 954 first year high school students. (More)