Related Experiment Video
Updated: Mar 22, 2026

Rapid Screening of HIV Reverse Transcriptase and Integrase Inhibitors
Published on: April 9, 2014
HIV Transmission Risk Persists During the First 6 Months of Antiretroviral Therapy
Andrew Mujugira1, Connie Celum, Robert W Coombs
1Departments of *Global Health; †Epidemiology; ‡Medicine; §Laboratory Medicine, University of Washington, Seattle, WA; ‖Division of Infectious Diseases and Tropical Pediatrics, University of Maryland, Baltimore, MD; ¶Department of Medicine, University of Manitoba, Winnipeg, Canada; #Department of Medical Microbiology, University of Manitoba, Winnipeg, Canada; **Department of Reproductive Health, Moi University, Eldoret, Kenya; ††Center for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya; ‡‡Center for Clinical Research, Kenya Medical Research Institute, Nairobi, Kenya; and §§Department of Reproductive Health and Research, World Health Organization, Geneva, Switzerland.
Objective:
Combination antiretroviral therapy (ART) decreases the risk of sexual HIV transmission by suppressing blood and genital HIV RNA concentrations. We sought to determine HIV transmission risk prior to achieving complete viral suppression.
Design:
Prospective cohort study.
Methods:
Using data from the Partners PrEP Study, a prospective study of 4747 heterosexual HIV-serodiscordant couples in Kenya and Uganda, we examined multiple markers of HIV transmission risk during the first months after ART initiation: time to viral suppression in blood, persistence of HIV RNA in genital specimens, sexual risk behavior, pregnancy incidence, and HIV transmission using survival analysis and generalized estimating equations logistic regression.
Results:
The cumulative probabilities of achieving blood viral suppression (<80 copies per milliliter) 3, 6, and 9 months after ART initiation were 65.3%, 84.8%, and 89.1%, respectively. Endocervical and seminal HIV RNA were detectable in 12% and 21% of samples obtained within 6 months of ART. Pregnancy incidence was 8.8 per 100 person-years during the first 6 months of ART, and sex unprotected by condoms was reported at 10.5% of visits. Among initially uninfected partners, HIV incidence before ART was 2.08 per 100 person-years (55 infections; 2644 person-years), 1.79 for 0-6 months after ART initiation (3 infections; 168 person-years), and 0.00 with >6 months of ART (0 infections; 167 person-years).
Conclusions:
Residual HIV transmission risk persists during the first 6 months of ART, with incomplete viral suppression in blood and genital compartments. For HIV-serodiscordant couples in which the infected partner starts ART, other prevention options are needed, such as pre-exposure prophylaxis, until viral suppression is achieved.
Related Concept Videos
Retrovirus Life Cycles
Sexually Transmitted Infections
Retroviruses
Size and Structure of Viral Genomes
Pulmonary Tuberculosis I
Causative Organism
The primary infectious agent causing tuberculosis is Mycobacterium tuberculosis, a slow-growing, acid-fast, aerobic rod that exhibits sensitivity to heat and ultraviolet light. Instances of Mycobacterium bovis and Mycobacterium avium contributing to the development of TB infection are rare.
Mode of...
Transmission-based Precautions I: Contact, Enteric, and Droplets
Contact Precautions:
Contact precautions are the measures taken to prevent the transmission of infectious agents, especially epidemiologically important microorganisms such as MRSA or influenza, primarily transmitted through direct or indirect contact with an...

