Journal Article

High Rates of Forward Transmission Events after Acute/Early HIV-1 Infection

Moisi, Daniela, Ntemgwa, Michel, Leblanc, Roger, Tremblay, Cecile, Thomas, Réjean, Routy, Jean-Pierre, Charest, Hugues, Wainberg, Mark A., Brenner, Bluma G., Rouleau, Danielle, Legault, Mario, Matte, Claudine, Bruneau, Julie, Roger, Michel, Baril, Jean-Guy

2007

Overview

Background. A population-based phylogenetic approach was used to characterize human immunodeficiency virus (HIV)—transmission dynamics in Quebec. Methods. HIV-1 pol sequences included primary HIV infections (PHIs; <6 months after seroconversion) from the Quebec PHI cohort (1998–2005; n = 215) and the provincial genotyping program (2001–2005; n = 481). Phylogenetic analysis determined sequence interrelationships among unique PHIs (n = 593) and infections from untreated (n = 135) and treated (n = 660) chronically infected (CI) potential transmitter populations (2001–2005). Clinical features, risk factors, and drug resistance for clustered and nonclustered transmission events were ascertained. Results. Viruses from 49.4% (293/593) of PHIs cosegregated into 75 transmission chains with 2–17 transmissions/cluster. Half of the clusters included 2.7 ± 0.8 (mean ± SD) transmissions, whereas the remainder had 8.8 ± 3.5 transmissions. Maximum periods for onward transmission in clusters were 15.2 ± 9.5 months. Coclustering of untreated and treated CIs with PHIs were infrequent (6.2% and 4.8%, respectively). The ages, viremia, and risk factors were similar for clustered and nonclustered transmission events. Low prevalence of drug resistance in PHI supported amplified transmissions at early stages. Conclusions. Early infection accounts for approximately half of onward transmissions in this urban North American study. Therapy at early stages of disease may prevent onward HIV transmission.

• Publisher: The University of Chicago Press,University of Chicago Press
• Subject: Adult / AIDS / Anti-HIV Agents - therapeutic use / Data transmission / Disease transmission / Disease Transmission, Infectious / DNA, Viral - analysis / Drug resistance / Drug Resistance, Viral - genetics / Female / Genes, pol / Genetic Variation / HIV / HIV 1 / HIV infections / HIV Infections - drug therapy / HIV Infections - epidemiology / HIV Infections - etiology / HIV Infections - transmission / HIV Infections - virology / HIV-1 - classification / HIV-1 - genetics / HIV/AIDS / Human immunodeficiency virus 1 / Humans / Infections / Male / Phylogenetics / Phylogeny / Quebec - epidemiology / Risk Factors / Sexual transmission