HIV-1 Transmission among Injecting Drug Users is Principally Derived from Local Circulating Strains in Guangxi, China

Area of Science:

• Epidemiology
• Molecular Biology
• Public Health

Background:

• Injection drug use (IDU) remains a significant route for human immunodeficiency virus (HIV) transmission.
• Understanding the evolving spatiotemporal dynamics of HIV transmission among IDUs is crucial for effective public health interventions.
• Recent shifts in HIV transmission patterns linked to IDU require detailed investigation.

Purpose of the Study:

• To analyze the spatiotemporal sources and transmission dynamics of HIV-1 among individuals who inject drugs (IDUs) in Guangxi province.
• To elucidate the characteristics of HIV transmission networks within the IDU population in the region.
• To identify key HIV-1 strains and their origins contributing to transmission.

Main Methods:

• Conducted a molecular epidemiological investigation of HIV infections in Guangxi from 2009 to 2019.
• Employed phylogenetic and Bayesian time-geographic analyses of HIV-1 sequences.
• Integrated sequence data with epidemiological information to map transmission pathways.

Main Results:

• The predominant HIV-1 strains identified were CRF08_BC (57.4%), CRF01_AE (28.4%), and CRF07_BC (10.7%).
• A significant proportion (72.6%) of infections were linked to transmission networks originating from other provinces.
• While most transmitted strains were locally endemic (93.6%), a notable percentage originated from other provinces, particularly Guangdong and Yunnan. HIV transmission primarily occurred between HIV-positive IDUs (92.1%).

Conclusions:

• Local HIV-1 strains are major drivers of transmission among IDUs in Guangxi, characterized by high diversity.
• Despite local endemicity, inter-provincial transmission links persist, highlighting the need for broader regional strategies.
• Enhanced coverage of existing prevention programs and strengthened inter-provincial collaboration, especially with Guangdong and Yunnan, are recommended.