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Studies find new HIV incidence falling in some SA communities

Two separate studies from KwaZulu-Natal in South Africa have been published in the last two months, both showing falls in new HIV infections in a region where over 20% of men and 40% of women are living with HIV.

Aidsmap reports that one study finds a 43% decline in HIV incidence in recent years in both men and women, with a larger and earlier decline in men. However, the other finds evidence only of a decline in young women aged 15 to 19, and none so far in men or older women.

The first study – the Hlabisa Study – was conducted by Dr Alain Vandormael at the Africa Health Research Institute (AHRI), University of KwaZulu-Natal (UKZN), Heidelberg Institute for Global Health (HIGH), University of Heidelberg, and KwaZulu-Natal Research Innovation and Sequencing Platform (KRISP), Professor Frank Tanser and colleagues, analysing data from an established cohort of all households in a specific area who are contacted annually and tested for HIV during researcher visits. Condom use in this population increased during the first decade of the century and by 2011 had reached over 60% (according to women) and 70% (according to men), with little change thereafter.

The proportion of men reporting they were circumcised increased from 3% in 2009 to 33% in 2016. HIV incidence in circumcised men decreased by 59% and in uncircumcised men by 42%.

The report says the second study – the Greater Edendale study – is a population cohort study, conducted by Dr Ayesha Kharsany at the Nelson R. Mandela School of Medicine, University of KwaZulu-Natal,  Professor Quarraisha Abdool Karim at UKZN and Mailman School of Public Health, Columbia University, and colleagues. Within the peri-urban Greater Edendale and rural Vulindlela areas near Pietermaritzburg in southern KwaZulu-Natal, the researchers randomly selected households and invited a single inhabitant aged between 15 and 49 years from each to take part. The respondents provided a range of data and were anonymously tested for HIV, with the results compared with their knowledge of their status.

The report says the authors of the Hlabisa study attribute the earlier and larger fall in incidence in men to two factors: the higher proportion of HIV-positive women that were on ART and virally suppressed, and rising circumcision rates.

In the Greater Edendale study on the other hand, a significant fall in incidence has only been seen in young women. The authors comment that “increases in the number of older HIV-seropositive men in age-disparate sexual partnerships who were using ART and had viral suppression may have led to the reduction observed in HIV incidence.”

Either way, the report says these studies both indicate that HIV testing and treatment, and prevention methods such as circumcision, are at least beginning to have a population-level effect on HIV incidence in this “hyperendemic” part of the world.

Abstract 1
Over the past decade, there has been a massive scale-up of primary and secondary prevention services to reduce the population-wide incidence of HIV. However, the impact of these services on HIV incidence has not been demonstrated using a prospectively followed, population-based cohort from South Africa—the country with the world’s highest rate of new infections. To quantify HIV incidence trends in a hyperendemic population, we tested a cohort of 22,239 uninfected participants over 92,877 person-years of observation. We report a 43% decline in the overall incidence rate between 2012 and 2017, from 4.0 to 2.3 seroconversion events per 100 person-years. Men experienced an earlier and larger incidence decline than women (59% vs. 37% reduction), which is consistent with male circumcision scale-up and higher levels of female antiretroviral therapy coverage. Additional efforts are needed to get more men onto consistent, suppressive treatment so that new HIV infections can be reduced among women.

Alain Vandormael, Adam Akullian, Mark Siedner, Tulio de Oliveira, Till Bärnighausen, Frank Tanser

Abstract 2
Importance: In Africa, the persistently high HIV incidence rate among young women is the major obstacle to achieving the goal of epidemic control.
Objective: To determine trends in coverage of HIV prevention and treatment programs and HIV incidence.

Design, Setting, and Participants: This cohort study consisted of 2 sequential, community-based longitudinal studies performed in the Vulindlela and Greater Edendale area in KwaZulu-Natal, South Africa. Participants enrolled from June 11, 2014, to June 22, 2015 (2014 survey), with a single follow-up visit from June 24, 2016, to April 3, 2017 (2016 cohort), or enrolled from July 8, 2015, to June 7, 2016 (2015 survey), with a single follow-up visit from November 7, 2016, to August 30, 2017 (2017 cohort). Men and women aged 15 to 49 years were enrolled in the 2014 and 2015 surveys, and HIV-seronegative participants aged 15 to 35 years were followed up in the 2016 and 2017 cohorts. Analysis was conducted from January 1 through December 31, 2018.
Exposures: HIV prevention and treatment programs in a real-world, nontrial setting.

Main Outcomes and Measures: Trends in sex- and age-specific HIV incidence rates, condom use, voluntary medical male circumcision, knowledge of HIV-seropositive status, uptake of antiretroviral therapy, and viral suppression.
Results: A total of 9812 participants (6265 women [63.9%]; median age, 27 years [interquartile range, 20-36 years]) from 11 289 households were enrolled in the 2014 survey, and 10 236 participants (6341 women [61.9%]; median age, 27 years [interquartile range, 20-36 years]) from 12 247 households were enrolled in the 2015 survey. Of these, 3536 of 4539 (annual retention rate of 86.7%) completed follow-up in the 2016 cohort, and 3907 of 5307 (annual retention rate of 81.4%) completed follow-up in the 2017 cohort. From 2014 to 2015, condom use with last sex partner decreased by 10% from 24.0% (n = 644 of 3547) to 21.6% (n = 728 of 3895; P = .12) in men and by 17% from 19.6% (n = 1039 of 6265) to 16.2% (n = 871 of 6341; P = .002) in women. Voluntary medical male circumcision increased by 13% from 31.9% (1102 of 3547) to 36.1% (n = 1472 of 3895); P = .007) in men, and the proportion of women reporting that their partner was circumcised increased by 35% from 35.7% (n = 1695 of 4766) to 48.2% (n = 2519 of 5207; P < .001). Knowledge of HIV-seropositive status increased by 21% from 51.8% (n = 504 of 3547) to 62.9% (n = 570 of 3895; P < .001) in men and by 14% from 64.6% (n = 1833 of 6265) to 73.4% (n = 2182 of 6341; P < .001) in women. Use of antiretroviral therapy increased by 32% from 36.7% (n = 341 of 3547) to 48.6% (n = 432 of 3895; P < .001) in men and by 29% from 45.6% (n = 1251 of 6265) to 58.8% (n = 1743 of 6341; P < .001) in women; HIV viral suppression increased by 20% from 41.9% (n = 401 of 3547) to 50.3% (n = 456 of 3895; P = .005) in men and by 13% from 54.8% (n = 1547 of 6265) to 61.9% (n = 1828 of 6341; P < .001) in women. Incidence of HIV declined in women aged 15 to 19 years from 4.63 (95% CI, 3.29-6.52) to 2.74 (95% CI, 1.84-4.09) per 100 person-years (P = .04) but declined marginally or remained unchanged among men and women in other age groups.
Conclusions and Relevance: This study showed a significant decline in HIV incidence in young women; however, to further reduce HIV incidence, HIV prevention and treatment program coverage must be intensified and scaled up.

Ayesha BM Kharsany; Cherie Cawood; Lara Lewis; Nonhlanhla Yende-Zuma; David Khanyile; Adrian Puren; Savathree Madurai; Cheryl Baxter; Gavin George; Kaymarlin-Govender; Sean Beckett; Natasha Samsunder; Carlos Toledo; Kassahun-Abere Ayalew; Karidia Diallo; Mary Glenshaw; Amy Herman-Roloff; Eduan Wilkinnson; Tulio de Oliveira; Salim S Karim; Quaraisha Abdool Karim

[link url=""]Aidsmap material[/link]

[link url=""]Nature Communications abstract[/link]

[link url=""]JAMA Network Open abstract[/link]

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