We applied the back-calculation method to estimate the magnitude of the HIV epidemic in Brazil, using the EM and EMS algorithms. Under certain assumptions regarding the behavior of infected patients towards combined antiretroviral therapy, we discuss five different scenarios applied to the Brazilian epidemic. Our objective was to illustrate the impact of combined antiretroviral treatment on the incubation period and thus on estimates of the size of the HIV-infected population, based on reported AIDS cases.
HIV; Acquired Immunodeficiency Syndrome; Surveillance; Highly Active Anti-Retroviral Therapy