Low AJ, Frederix K, McCracken S, Manyau S, Gummerson E, Radin E, Davia S, Longwe H, Ahmed N, Parekh B, Findley S, Schwitters A.
PLoS Med. 2019 Jan 14;16(1):e1002727. doi: 10.1371/journal.pmed.1002727. eCollection 2019 Jan.
A previous analysis of the impact of drought in Africa on HIV demonstrated an 11% greater prevalence in HIV-endemic rural areas attributable to local rainfall shocks. The Lesotho Population-Based HIV Impact Assessment (LePHIA) was conducted after the severe drought of 2014-2016, allowing for reevaluation of this relationship in a setting of expanded antiretroviral coverage.
METHODS AND FINDINGS:
LePHIA selected a nationally representative sample between November 2016 and May 2017. All adults aged 15-59 years in randomly selected households were invited to complete an interview and HIV testing, with one woman per household eligible to answer questions on their experience of sexual violence. Deviations in rainfall for May 2014-June 2016 were estimated using precipitation data from Climate Hazards Group InfraRed Precipitation with Station Data (CHIRPS), with drought defined as <15% of the average rainfall from 1981 to 2016. The association between drought and risk behaviors as well as HIV-related outcomes was assessed using logistic regression, incorporating complex survey weights. Analyses were stratified by age, sex, and geography (urban versus rural). All of Lesotho suffered from reduced rainfall, with regions receiving 1%-36% of their historical rainfall. Of the 12,887 interviewed participants, 93.5% (12,052) lived in areas that experienced drought, with the majority in rural areas (7,281 versus 4,771 in urban areas). Of the 835 adults living in areas without drought, 520 were in rural areas and 315 in urban. Among females 15-19 years old, living in a rural drought area was associated with early sexual debut (odds ratio [OR] 3.11, 95% confidence interval [CI] 1.43-6.74, p = 0.004), and higher HIV prevalence (OR 2.77, 95% CI 1.19-6.47, p = 0.02). It was also associated with lower educational attainment in rural females ages 15-24 years (OR 0.44, 95% CI 0.25-0.78, p = 0.005). Multivariable analysis adjusting for household wealth and sexual behavior showed that experiencing drought increased the odds of HIV infection among females 15-24 years old (adjusted OR [aOR] 1.80, 95% CI 0.96-3.39, p = 0.07), although this was not statistically significant. Migration was associated with 2-fold higher odds of HIV infection in young people (aOR 2.06, 95% CI 1.25-3.40, p = 0.006). The study was limited by the extensiveness of the drought and the small number of participants in the comparison group.
Drought in Lesotho was associated with higher HIV prevalence in girls 15-19 years old in rural areas and with lower educational attainment and riskier sexual behavior in rural females 15-24 years old. Policy-makers may consider adopting potential mechanisms to mitigate the impact of income shock from natural disasters on populations vulnerable to HIV transmission.