Incidence

Greater knowledge around HIV transmission, epidemic dynamics, and the vulnerabilities of key populations can support the development of sustainable, effective services for HIV prevention and treatment.

In the era of ART, increases in HIV prevalence will be a natural consequence of the success of treatment for HIV. This has two important implications for epidemic surveillance:

MeSH_30_30Declining mortality rates and changing mortality profiles affect the predictive ability of HIV epidemic models.
MeSH_30_30Link between HIV incidence and HIV prevalence becomes more complex, making the need for identification of recently infected cases of HIV infection more important.

Given the ambitions of ending the epidemic by 2030, it is essential to improve epidemic models and methods for directly measuring HIV incidence in order to monitor epidemic trends and to measure the impact of prevention programmes.

What does MeSH aim to do in this area?

MeSH_30_30Assess the feasibility and utility of HIV infection recency testing in a range of service-provision contexts. This work will impact people at high risk of HIV infection, people living with HIV, and people in wider societies adversely affected by HIV morbidity and mortality.
MeSH_30_30Develop the use of RITAs in the context of routine HIV surveillance in order to improve the predictive ability of HIV epidemic models.

What is MeSH working on and achieved so far?

This project has recently been funded and is now being rolled out . Three pilot studies will be conducted in the next phase of the work.

MeSH_30_30In clinics providing prevention of mother to child transmission (PMTCT) services we will assess the potential for HIV incidence surveillance using HIV recency assay tests in clinics providing HIV testing linked to prevention of mother to child transmission (PMTCT) services
MeSH_30_30In partnership with a health outreach programme for female sex workers we will investigate the routine use of RITA assays in this context.
MeSH_30_30 In HIV testing and counselling clinics we will assess the feasibility of integrating surveillance for recent infection with other data routinely recorded.

Using Recent Infection Testing Algorithms (RITAs) to distinguish recently acquired infection from long-standing infection among persons newly diagnosed with HIV can help identify populations, defined by behavior and/or geography, where current transmission is occurring.

As a disproportionate number of HIV transmissions originate from people who have early HIV infection, targeting effective prevention and behavioural interventions to populations presenting with recent infections could have a large impact on overall levels of transmission. The idea of a diagnostic algorithm that can accurately identify recent HIV infections without the need for follow-up has long been thought to be a key step forward in HIV surveillance.