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Amplifying and Quantifying HIV-1 RNA in HIV Infected Individuals with Viral Loads Below the Limit of Detection by Standard Clinical Assays
Published on: September 26, 2011
Is the HIV-2 pandemic going extinct 40 years after virus discovery?
Vicente Soriano1, Berenger Konan2, Rose Segla2
1UNIR Health Sciences School & Medical Center, Madrid, Spain.
Summary
Human Immunodeficiency Virus type 2 (HIV-2) shows lower replication and transmission than HIV-1, leading to slower disease progression. Antiretroviral therapy options are more limited but some drugs remain effective for HIV-2 management.
Area of Science:
- Virology
- Immunology
- Epidemiology
Background:
- Human Immunodeficiency Virus type 2 (HIV-2) is a retrovirus closely related to HIV-1, identified in 1986.
- HIV-2 is prevalent in West Africa and characterized by lower viral replication and transmission rates compared to HIV-1.
Purpose of the Study:
- To summarize the key characteristics of HIV-2, including its virology, clinical course, and treatment.
- To highlight the epidemiological trends of the HIV-2 pandemic.
Main Methods:
- Review of existing literature on HIV-2.
- Analysis of epidemiological data regarding HIV-2 prevalence and trends.
Main Results:
- HIV-2 exhibits lower plasma viremia, reduced sexual and vertical transmission, and slower CD4+ T-cell decline than HIV-1.
- Many HIV-2 patients remain asymptomatic for over 15 years, with over 10% potentially remaining asymptomatic lifelong.
- HIV-2 shows lower susceptibility to antiretroviral drugs; non-nucleoside reverse transcriptase inhibitors are inactive, while some protease inhibitors and all integrase inhibitors are effective.
- Specific viral load tests are required for monitoring HIV-2.
- Epidemiological surveys indicate a declining global and regional pandemic of HIV-2.
Conclusions:
- HIV-2 represents a distinct clinical and epidemiological entity compared to HIV-1.
- Management of HIV-2 requires specific diagnostic and therapeutic approaches.
- The HIV-2 pandemic is decreasing globally.
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