Test and Treat Principle Reduces the Number of New HIV Cases in South Africa by 30%
According to the latest data presented at the Conference on Retroviruses and Opportunistic Infections (CROI), the number of new HIV infections in southern Africa can be significantly reduced by voluntary testing for HIV in communities and immediately referring to treatment of all who gave a positive result. .
The HPTN071 (PopART) study showed that the number of new HIV infections was 30% lower in groups, where, along with proposing other proven preventive measures, for those who gave a negative result, the described method was used.
A randomized study involving about a million people in Zambia and South Africa was conducted by researchers from the London School of Hygiene and Tropical Medicine (LSHTM) and Imperial College London. His results showed that a similar decrease in the number of new HIV cases was not observed in communities where immediate responders were offered to those who tested positive. To explain this, a group of experts from the UK conducted an analysis.
In 2017, there were about 37 million people living with HIV worldwide, with 1.8 million new diagnoses annually. According to data from international organizations, today the incidence of HIV is steadily declining, but it is unlikely that it will succeed by 2020 to achieve the UNAIDS goal of less than 500,000 new infections per year. This requires a sharp decline in incidence, especially in southern Africa, where HIV coverage is higher than anywhere else in the world.
The study reports the latest results of PopART HPTN071, a randomized study that seeks to see whether the “universal testing and treatment” strategy can reduce the number of new HIV infections in Zambia and South Africa.
The work was carried out by researchers from LSHTM and Imperial College London in collaboration with the HIV Prevention Research Network (HPTN), Zambart (Zambia), Desmond Tutu Tuberculosis Control Center (South Africa) and Oxford University, and was funded by PEPFAR. The research was also sponsored by the National Institute of Allergy and Infectious Diseases, which is part of the NIH.
Research leader Professor Richard Hayes of the London School of Hygiene and Tropical Medicine said:
“People living with HIV, reaching and maintaining an undetectable level of viral load in the blood, accepting and adhering to antiretroviral therapy (ART) did not sexually transmit HIV. This factor was of key importance for “mass testing and treatment”, the task of which is to ensure that every person in the group knows their HIV status, and all those living with HIV are very quickly sent for treatment. Our study showed that the strategy of combination prevention "universal testing and treatment" can be an effective tool to slow the global HIV epidemic. "
PopART took place from 2013 to 2018 in 21 communities in South Africa and Zambia. Each of them had an average of 50 thousand inhabitants, and they corresponded to the geographical location and the proposed area of wide coverage of HIV. Communities were randomly assigned to one of three groups.
The first of them (A) underwent annual voluntary door-to-door HIV testing, and provided for the immediate start of treatment for those who tested positive for the test, and a series of proven HIV prevention measures for those who tested negative.
The other group (B) received the same services, except that treatment was provided in accordance with national guidelines.
The third group (C) was a control group and received HIV prevention and testing services in accordance with local standards of care.
At the beginning of the study, national guidelines for treating HIV in Zambia and South Africa indicated that people living with HIV should start ARVT when the number of immune cells in their blood (CD4 +) reaches 350 cells or less. In 2014, this threshold was increased to 500 cells, and in 2016, countries recommended that anyone diagnosed with HIV should immediately start ART, regardless of the number of CD4 +.
To measure the impact of interventions, the researchers formed a randomized sample of 48,300 adults aged 18 to 44 years. Scientists visited these participants at the beginning of the test, and then once a year for three years collected data using a questionnaire and a blood test, including an HIV test.
In the course of the work, specialists found that the incidence rate of HIV in group B was 30% lower than in the control group. In group A, on the contrary, there was only a slight decrease (7%).
The researchers found everyone who tested positive for HIV by the second year of the study, as well as those who had an undetectable level of the virus. Zero viral load reached 72% of study participants in group A, 68% in group B, and 60% in group C.
Professor Sarah Fiedler, driver of Imperial College in London, said: “The idea of our study was that if the majority of people living with HIV know their status and receive treatment, the risk of transmission of the virus will be noticeably reduced. The results show that this approach has been successful, and we hope that the results will help reduce the number of new HIV cases worldwide. ”
LSHTM professor Helen Isles, who led the study in Zambia, said:
“We have seen very strong evidence that the number of new HIV infections can be reduced by one-third thanks to a prevention strategy in which treatment of HIV infection begins in accordance with national guidelines. We did not see anything like this when, from the very beginning, studies suggested that people undergo universal treatment. We are currently conducting additional analyzes to establish the reasons for this. ”
The authors found that treatment coverage was lower among young people (under the age of 30) and men. Treatment and prevention programs must fill the gaps in coverage found in order to fully realize the potential of strategies such as PopART.