Introduction. Despite evidence from harm reduction programs, there are limited data on their impact in Mexico. The Mexican National HIV Program has supported harm reduction programs implemented by community-based organizations both financially and technically. Objective. To obtain an estimate of HIV infections averted from 2015 to 2018. Method. A deterministic model was developed to estimate the number of infections, with harm reduction projects financed by CENSIDA and implemented by Community-Based Organizations, using data reported from the period 2015 to 2018. The benefit was obtained by estimating the costs of providing prevention programs and comparing the latter to the costs of providing care. Results. An analysis of 66,973 people included in harm reduction programs showed that an estimated 869 HIV infections were averted between 2015 and 2018. Potential savings obtained by providing these harm reduction services exceeded over $600,000 Mexican pesos for every infection averted. Discussion and conclusion. Harm reduction services play a key role in reducing the incidence of HIV in Mexico. Ensuring their financing is necessary since, combined with other services, they are a cost-effective tool for reducing the economic and public health burden of HIV/AIDS.

Introduction. Efforts to identify new cases of HIV, HVC and other STIs, through the application of quick tests, focus on people who inject drugs, without taking into account the fact that the use of alcohol and other drugs of abuse inhibits decision making, increasing the transmission of STIs through risky sexual practices. Accordingly, it is necessary to have detection algorithms that consider people who use multiple drugs to improve the identification of new cases and their subsequent linkage with health services. Objective. This paper describes the development process of the OPB-APR model for the detection, counseling and referral of people with HIV and other STIs at addiction treatment centers. Method. The procedure is divided into three phases: 1. A literature review to identify the basic concepts of HIV and other STIs, substance use, risky sexual behaviors, quick tests, and specialized psychological counseling; 2. A feasibility study in which a health professional is trained to implement the OPB-APR model; 3. Drafting of the final version. Results. The final version of the OPB-APR model was obtained, which describes standardized procedures for detection, counseling and referral to health services. Discussion and conclusions. The OPB-APR model aims to strengthen the public health system by increasing the coverage of services for the detection of HIV, HCV and other STIs. The above through the implementation of standardized procedures among specialized and non-specialized health professionals of addiction care centers.