Incidence and Prevalence of Intrasubtype HIV-1 Dual Infection in At-Risk Men in the United States.
|Title||Incidence and Prevalence of Intrasubtype HIV-1 Dual Infection in At-Risk Men in the United States.|
|Publication Type||Journal Article|
|Year of Publication||2013|
|Authors||Wagner GA, Pacold ME, Kosakovsky Pond SL, Caballero G, Chaillon A, Rudolph AE, Morris SR, Little SJ, Richman DD, Smith DM|
|Journal||J Infect Dis|
|Date Published||2013 Nov 22|
Background. HIV-1 dual infection (DI) has been associated with decreased CD4 T-cell counts and increased viral loads; however, the frequency of intrasubtype DI is poorly understood. We used ultradeep sequencing (UDS) to estimate the frequency of DI in a primary infection cohort of predominantly men who have sex with men (MSM).Methods. HIV-1 genomes from longitudinal blood samples of recently-infected, therapy-naive participants were interrogated with UDS. DI was confirmed when maximum sequence divergence was excessive and supported by phylogenetic analysis. Co-infection was defined as DI at baseline; superinfection was monoinfection at baseline and DI at a later timepoint.Results. Of 118 participants, 7 were co-infected and 10 acquired superinfection. Superinfection incidence rate was 4.96 per 100 person-years (95%CI 2.67-9.22); 6 occurred in the first year and 4 in the second. Overall cumulative prevalence of intrasubtype B DI was 14.4% (95%CI 8.6%-22.1%). Primary HIV-1 incidence was 4.37 per 100 person-years (95%CI 3.56-5.36).Conclusions. Intrasubtype DI was frequent and comparable to primary infection rates among MSM in San Diego, however, superinfection rates declined over time. DI is likely an important component of the HIV epidemic dynamics, and development of stronger immune responses to the initial infection may protect from superinfection.
|Alternate Title||J. Infect. Dis.|