A new study conducted in Uganda and seven other African countries has revealed that young women who have sexual partners aged 25 to 34 years are three times as likely to acquire HIV.Those with partners aged 35 to 44 have more than a ninefold increase in risk, compared to young women whose partners were in the same age group.
The study whose results are published in the journal AIDS was also conducted in Eswatini, Lesotho, Malawi, Namibia, Tanzania, Zambia, and Zimbabwe and now researchers say each one-year increase in partner age is associated with a 9 per cent greater likelihood of recent HIV acquisition among females between 15 and 24 years.
This study aimed to examine the relationship between male partner age and prevalent HIV infection in young women using population-level data, including measures of male partner infectiousness. They also captured data on cohabiting male partners’ age and HIV status.
Dr Sarah Ayton, the lead researcher says they used the Population-Based HIV Impact Assessment surveys conducted between 2015 and 2017 in Eswatini, Lesotho, Malawi, Namibia, Tanzania, Uganda, Zambia, and Zimbabwe. Both females and males took part in these nationally representative surveys.
The questionnaire included questions on lifetime and past-year sexual behaviours and characteristics of the three most recent past-year sexual partners. Blood samples were taken to test for HIV, viral load and CD4 cell count.
A total of 17,813 adolescent girls and young women between 15 and 24 years provided data and a total of 63,081 men aged 15 to 59 years also took part in the surveys. A total of 19,818 men reported adolescent girls and young women as partners. Of these, 5381 cohabitated with females who also took part in the study.
29 per cent of the cohabiting men had two or more past-year sexual partners and 10 per cent reported condom use at the last sex. A total of 287 were living with HIV but only 153 were aware of their HIV status and 177 had viral load over 1000. Among the females, 58 had recently acquired HIV.
Overall, results reveal HIV incidence increased with partner age, peaking at 1.6% in women with partners aged 35 to 44 years. The total number of new HIV cases was highest among those with a partner aged 25 to 34 years.
In an additional analysis of 5381 couples in which both the female and male partners took part in the survey, the results were similar. In addition, the male partner having a high viral load was associated with 47 times greater odds of the female partner having HIV.
Young women with lower educational attainment, early sexual debut, multiple recent partners, and lower condom use were more likely to have partners aged 35 to 44. Rural women, those from Tanzania or Uganda, and married or divorced young women had significantly higher odds of partnerships with older men aged 45 to 59.
The authors suggest that programs promoting education and women’s economic empowerment could interrupt this cycle of vulnerability.
In Uganda, young women still account for a higher HIV prevalence rate than young men as results of the latest UPHIA survey show HIV prevalence was 0.2 per cent in men aged 15 to 19 years and 1.6 per cent in men aged 20 to 24 years. Similarly, HIV prevalence was 1.7 per cent in women aged 15 to 19 years and 4.2 per cent in women aged 20 to 24 years.