Summary Overview

March 2, 2020

The Ya Tsie study evaluated whether it was feasible and acceptable to scale up a combination of prevention interventions, with a focus on universal HIV testing and treatment, and whether these interventions would lower the rate of new HIV infections occurring in adults within a community.

The intervention included widespread HIV testing (home-based, mobile, and targeted); active patient tracing and linkage to care; universal antiretroviral treatment; rapid treatment start (at first clinic visit); and enhanced male circumcision services.

At the start of the study, Botswana already had high levels of HIV diagnosis, treatment, and viral suppression rates (close to UNAIDS 90-90-90 targets). By the end of the study, in the intervention arm, 88% of all persons living with HIV were on antiretroviral treat (ART) and virally suppressed (achieving UNAIDS 95-95-95 targets). In addition, HIV incidence was 30% lower in the intervention arm compared with the control arm over a short (29-month) follow-up period.

Through the interventions of the Ya Tsie study, we were able to achieve one of the highest reported population levels of HIV diagnosis, linkage to care, and viral suppression globally. We were also able to reduce population HIV incidence by about one-third over a short period of time. These results were achieved in a resource-constrained setting with high pre-existing testing and treatment coverage. 

Community Members at the Kgotla
Photo © Dominic Chavez


The Ya Tsie study (also called the Botswana Combination Prevention Project) was the largest community-based HIV/AIDS prevention study ever conducted in Botswana. The study took place in 30 peri urban and rural communities over a five-year period, from 2013-2018. 

The name Ya Tsieis a shortened form of a longer Setswana proverb, “Kgetsi ya tsie e kgonwa ke go tshwaraganelwa,”which means “team work bears more fruit than individual effort.” The Ya Tsie study was collaboratively conducted by the Botswana Ministry of Health and Wellness (BW); the Botswana Harvard AIDS Institute Partnership (BW); the Harvard T.H. Chan School of Public Health (USA); and the Centers for Disease Control and Prevention (USA) with Tebelopele and Jhpiego (BW) as implementing partners.

The Ya Tsie study was funded by PEPFAR, the U.S. President’s Emergency Plan for AIDS Relief through the Centers for Disease Control and Prevention.

The Need

In 2011, the estimated HIV incidence in Botswana was 1.35%. In other words, 135 out of 10,000 people were getting newly infected with HIV every year. 

Botswana has made significant progress in its response to the HIV epidemic in recent years. In order to meet its commitment to end the AIDS epidemic as a public health threat by 2030, Botswana must determine the best available methods to stop new HIV-infections. 

The Goal

The Ya Tsie study’s primary objective was to determine whether a package of interventions, primarily universal testing and treatment would impact the HIV/AIDS epidemic by significantly reducing the number of new HIV infections in 16-64-year-olds in 15 villages in Botswana over a three-year period.

Why Botswana?

Botswana has the third highest HIV prevalence in the world, with more than one in five of the adult population aged 15-49 years living with the virus. Although Botswana has a high HIV prevalence, the country has been a world leader in HIV/AIDS treatment and prevention efforts. In 2001, Botswana was the first country in southern Africa to provide free treatment to people living with HIV (PLWH)