Declines in HIV incidence have been slower than expected during the roll-out of antiretroviral treatment (ART) services in sub-Saharan African populations suffering generalized epidemics. Using data from a population-based, open cohort HIV sero-survey (2004–13), we found evidence for initial reductions in sexual activity and multiple sexual partnerships, followed by increases during the period of ART scale-up in areas of high HIV prevalence in Manicaland, east Zimbabwe. Recent population-level increases in condom use were also recorded, but largely reflected high use by the rapidly growing proportion of HIV-infected individuals on treatment. Sexual risk behaviour increased in susceptible uninfected individuals and in untreated (and therefore more infectious) HIV-infected men, which may have slowed the decline in HIV incidence in this area. Intensified primary HIV prevention programmes, together with strengthened risk screening, referral, and support services following HIV testing, could help to maximize the impact of ‘test-and-treat’ programmes in reducing new infections.

在遭受普遍流行病的撒哈拉以南非洲人群推出抗逆转录病毒治疗 (ART) 服务期间，艾滋病毒发病率的下降速度低于预期。使用来自基于人群的开放队列 HIV 血清调查（2004-13 年）的数据，我们发现了性活动和多重性伙伴关系最初减少的证据，随后在艾滋病毒高发地区扩大抗逆转录病毒治疗期间有所增加流行于津巴布韦东部的马尼卡兰。近期安全套使用的人口水平也有所增加，但这在很大程度上反映了接受治疗的艾滋病毒感染者比例迅速增长的高使用率。易感未感染个体和未经治疗（因此更具传染性）的 HIV 感染男性的性风险行为增加，这可能减缓了该地区 HIV 发病率的下降。