Molecular epidemiology of HIV-1 transmission in a cohort of HIV-1 concordant heterosexual couples in Dakar, Senegal
Background: A large number of HIV-1 infections in Africa occur in married couples. The predominant direction of
intracouple transmission and the principal external origins of infection remain important issues of debate.
Methods: We investigated HIV-1 transmission in 46 HIV-1 concordant positive couples from Dakar, Senegal. Intracouple
transmission was confirmed by maximum-likelihood phylogenetic analysis and pairwise distance comparisons of HIV-1 env
gp41 sequences from both partners. Standardized interview data were used to deduce the direction as well as the external
sources of the intracouple transmissions.
Results: Conservative molecular analyses showed linked viruses in 34 (74%) couples, unlinked viruses in 6 (13%) couples,
and indeterminate results for 6 (13%) couples. The interview data corresponded completely with the molecular analyses: all
linked couples reported internal transmission and all unlinked couples reported external sources of infection. The majority
of linked couples (93%) reported the husband as internal source of infection. These husbands most frequently (82%)
reported an occasional sexual relationship as external source of infection. Pairwise comparisons of the CD4 count,
antiretroviral therapy status, and the proportion of gp41 ambiguous base pairs within transmission pairs correlated with the
reported order of infection events.
Conclusions: In this suburban Senegalese population, a majority of HIV-1 concordant couples showed linked HIV-1
transmission with the husband as likely index partner. Our data emphasize the risk of married women for acquiring HIV-1 as
a result of the occasional sexual relationships of their husbands.
Auteur(s) : Jennes W, Kyongo J, Vanhommerig E, Camara M , Coppens S, Seydi M, Mboup S, Heyndrickx L, Kestens L
Pages : e37402
Année de publication : 2012
Revue : PLoS ONE
N° de volume : 07
Type : Article
Mise en ligne par : CAMARA Makhtar