HIV-2 Infection: Where Are We Today?

Area of Science:

• Medical Diagnostics
• Infectious Diseases
• Virology

Background:

• Antiretroviral therapy (ART) choices differ significantly between Human Immunodeficiency Virus type 1 (HIV-1) and HIV type 2 (HIV-2).
• Accurate differentiation between HIV-1 and HIV-2 is essential for appropriate patient management and treatment selection.

Purpose of the Study:

• To determine the prevalence of HIV-2 infection within the study center.
• To evaluate the effectiveness of the existing diagnostic algorithm in correctly identifying HIV types (HIV-1, HIV-2, or co-infection).

Main Methods:

• Retrospective analysis of HIV-infected patients over three years at a tertiary care teaching institute.
• Patients were classified as HIV-1, HIV-2, or HIV-1 and HIV-2 co-infected based on NACO/WHO HIV testing strategy III results.
• Immunoblotting at a National Reference Laboratory was used to resolve discordant results.

Main Results:

• Out of 66,708 tested patients, 5,238 (7.9%) were HIV positive.
• HIV-1 accounted for 7.62%, HIV-2 for 0.14%, and co-infection for 0.08%.
• The diagnostic algorithm failed to differentiate HIV types in 1.2% of cases.

Conclusions:

• The current diagnostic algorithms require modification to accurately diagnose and confirm HIV-2 infections, especially in regions with ongoing epidemics of both HIV-1 and HIV-2.
• Improved diagnostic strategies are needed to ensure correct identification of HIV types for optimal patient care.