Surveillance of transmitted HIV drug resistance among women attending antenatal clinics in Dar es Salaam, Tanzania.

Background: In resource-limited settings where antiretroviral treatment (ART) access is being scaled-up, the World Health Organization (WHO) recommends surveillance of transmitted HIV drug resistance (HIVDR). We used the WHO HIVDR threshold survey method to assess transmitted HIVDR in Dar es Salaam where ART was introduced in 1995 and where approximately 11,000 people are currently on ART.

Methods: From November 2005 to February 2006, dried blood spot (DBS) specimens were made from remnant specimens collected during the national HIV serosurvey from 60 primagravidas <25 years old attending six antenatal clinics for routine syphilis testing.

Socio-economic and demographic factors associated with prevalence of HIV infection among pregnant women in Dar es Salaam, Tanzania.

Background: HIV/AIDS epidemic has become generalised in low resource settings in sub-Saharan Africa where 90% of all maternal-foetal transmission of HIV infection occurs. Global effort to scale-up pMTCT is underway, however, mechanisms to maximise screening of HIV- 1 positive women for Nevirapine treatment and other interventions, are not clear.

Objective: To identify socioeconomic and demographic characteristics associated with the prevalence of HIV- 1 infection among Tanzanian women.

HIV-1 LTR subtype and perinatal transmission.

Multiple subtypes of HIV-1 have been identified; however, there is little data on the relative transmissibility of viruses belonging to different subtypes. A matched case-control study addressed whether viruses with different long terminal repeat (LTR) subtypes were transmitted equally from mother to infant. The LTR subtype was determined for 45 matched cases and controls who participated in a clinical trial in Tanzania.

A new human immunodeficiency virus type 1 circulating recombinant form from Tanzania.

It is becoming increasingly important to identify and to study human immunodeficiency virus type 1 (HIV-1) circulating recombinant forms (CRFs) with evidence of epidemic spread, since mosaic strains arise frequently, especially in populations where multiple subtypes cocirculate. We describe the almost complete nucleotide sequence of 3 subtype C and D recombinant viruses, selected from a pool of 13 D(gag)-D/C/D(env) perinatally infected infants from Dar es Salaam, Tanzania. All three genomes had cross-over points with approximately the same genomic localization.

Differences in perinatal transmission among human immunodeficiency virus type 1 genotypes.

Objective: To determine whether genotypes from human immunodeficiency virus type 1 (HIV-1) subtypes A, C, or D or intersubtype recombinants have the same probability of being transmitted from mother to child.

Methods: We determined the HIV-1 genetic subtype and maternal risk factors of 51 matched transmitting and nontransmitting mothers from Tanzania. The HIV-1 gag (p24-p7) and env (C2-C5) nucleotide sequences were used for genotype classification, and matched logistic regression analysis was used to assess differences among genotypes.