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A Restriction Enzyme Based Cloning Method to Assess the In vitro Replication Capacity of HIV-1 Subtype C Gag-MJ4 Chimeric Viruses
Published on: August 31, 2014
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Evolutionary dynamics of HIV-1 subtype C in Brazil
Bernardino Souto1,2,3, Vera Triunfante1,2, Ana Santos-Pereira1,2
1Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal.
Scientific Reports
|November 30, 2021
Summary
HIV-1 subtype C, prevalent globally, drives a major epidemic in South Brazil. This subtype shows distinct transmission patterns and clinical characteristics compared to subtype B, influencing its geographical spread.
Area of Science:
- Virology
- Epidemiology
- Immunology
Background:
- Human Immunodeficiency Virus type 1 (HIV-1) genetic diversity poses challenges for prevention and treatment.
- Subtype C is the most prevalent globally, primarily in Africa and Asia, but its significant presence in South Brazil is unusual.
- Understanding the factors driving subtype C's epidemic in Brazil is crucial for public health strategies.
Purpose of the Study:
- To investigate the molecular epidemiology and clinical characteristics of HIV-1 subtype C in South Brazil.
- To elucidate the reasons behind the large HIV-1 subtype C epidemic in a region dominated by subtype B.
- To understand the transmission dynamics and geographical expansion of HIV-1 subtype C within Brazil and internationally.
Main Methods:
- Analysis of clinical data and viral sequences from 2611 treatment-naïve HIV-1 patients in Brazil.
- Molecular epidemiology to identify transmission clusters and patterns.
- Comparison of clinical outcomes, including CD4+ T cell counts, between subtype C and subtype B infections.
Main Results:
- Identification of 35 distinct transmission clusters of HIV-1 subtype C, indicating local and widespread transmission.
- Subtype C infections were associated with a lower probability of CD4+ T cell deficiency compared to subtype B.
- HIV-1 epidemics in South Brazil showed high female-to-male infection ratios and significant mother-to-child transmission.
Conclusions:
- HIV-1 subtype C may leverage longer asymptomatic periods for transmission, contributing to its spread.
- Subtype C's expansion is influenced by factors like female-to-male transmission ratios and mother-to-child transmission.
- The study provides insights into the geographical distribution and expansion patterns of major HIV-1 subtypes.
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