The Dynamics of HIV-1 Epidemic Among Older Adults in Eastern China: Identifying the Role and Linkage of HIV Transmission

Abstract

Background: While an unhalted upsurge of HIV/AIDS epidemic among older adults has recently been witnessed in China, the HIV transmission pattern and characteristics among older adults have not been elucidated clearly. This study aims to identify determinants and linkages along the HIV transmission pathway among older adults, and to have a better insight of HIV dynamics in China. Methods: In this epidemiological field survey, we recruited HIV-positive individuals and their close HIV-positive contacts diagnosed in one county with skyrocket-increase HIV epidemic in eastern China, Zhejiang province. We used phylogenetic analysis to verify a potential transmission network in the region. Findings: A total of 200 HIV-infected individuals in SY County, Zhejiang province were enrolled. Most of them were males (142, 71·0%), aged ≥50 years at HIV diagnosis (129, 64·5%), and with household registration in SY County (179, 89·5%). A molecular cluster of 71 participants with CRF 08_BC was identified, including three commercial sex workers (CSWs), 48 male clients (41 of them aged ≥50 years at HIV diagnosis). Each CSWs in this cluster had 23-66 virus linkages with other participants. Among participants aged ≥50 years at HIV diagnosis, 65·9% (85/129) were infected through commercial sex, among them, 97·4% (75/77) were clustered and 75·3% (58/77) were infected with circulating recombinant form virus (CRF) subtype CRF 08_BC. While, the corresponding percentages for participants aged <50 years at HIV diagnosis were 50·7% (36/71), 71·9% (23/32) and 46·9% (15/32). Most of the commercial sex occurred in street-based rental rooms, while sex-money exchange through gambling cards, and having sex while nursing older males were found to be emerging patterns of commercial sexual in rural areas. Interpretation: We found evidence of sustained commercial sexual behavior in diverse and concealed patterns between CSWs and older males through epidemiological investigation and phylogenetic analysis. One of the untreated CSW played a crucial role in HIV transmission among male clients and further leading HIV transmission within families. Public health intervention should target on controlling the infections of HIV diagnosed patients and decreasing risk behavior to reduce onward HIV transmission among seniors in China. Funding Statement: Health Commission of Zhejiang province, China, Funding number: 2019KY356 to JJ. Declaration of Interests: No other competing interests exist. Ethics Approval Statement: Ethical approval for this study was granted by the Institutional Review Board (IRB) of Zhejiang Provincial Center for Disease Control and Prevention. All experiments were performed in accordance with the relevant guidelines and regulations.