Primary HIV-1 subtype C infection in Ethiopia

Area of Science:

• Immunology
• Virology
• Epidemiology

Background:

• Prospective cohort studies are crucial for understanding human immunodeficiency virus type 1 (HIV-1) infection dynamics.
• Ethiopia has a significant burden of HIV-1, necessitating localized research on disease progression and viral characteristics.
• Comparing HIV-1 seroconversion in different populations can reveal important differences in host-pathogen interactions.

Purpose of the Study:

• To investigate HIV-1 seroprevalence and incidence among factory workers in Akaki and Wonji, Ethiopia.
• To compare immunological profiles (CD4 and CD8 T-cell counts) and viral loads between Ethiopian and Dutch HIV-1 seroconverters.
• To characterize the HIV-1 subtypes circulating in the Ethiopian cohort and their association with viral load.

Main Methods:

• Enrollment of 1624 Ethiopian factory workers into prospective HIV-1 cohorts between 1997 and 2001.
• Monitoring of HIV-1 serostatus, CD4/CD8 T-cell counts, and viral loads during follow-up.
• HIV-1 subtyping of seroconverters to identify specific strains, including subtype C and its sub-clusters.

Main Results:

• HIV-1 seroprevalence was 11.8% in Akaki and 7.1% in Wonji; incidence rates were 0.75 and 0.35 per 100 person-years, respectively.
• Ethiopian seroconverters exhibited lower CD4 T-cell counts and higher CD8 T-cell counts compared to Dutch seroconverters.
• All Ethiopian seroconverters were infected with HIV-1 subtype C, with higher viral loads observed in those infected with sub-cluster C'.

Conclusions:

• Significant differences in immune responses and viral dynamics exist between Ethiopian and Dutch HIV-1 seroconverters.
• HIV-1 subtype C, particularly sub-cluster C', appears to be associated with distinct viral load characteristics in this Ethiopian cohort.
• The findings highlight the importance of regional surveillance and characterization of HIV-1 infection patterns and host responses.