title: HIV-1 vertical transmission in Rio Grande, Southern Brazil.
abstract: The aim of this study was to determine the rate and risk factors of HIV-1 mother-to-child transmission (MTCT), the timing of transmission and the transmitted subtype in a population where subtypes B and C co-circulate. One hundred and forty-four babies born to HIV-1-infected mothers were studied. Subtype and timing of transmission were determined by a nested polymerase chain reaction of the gp41 gene. Seven children were infected (4.9%): four were infected intrautero and one intrapartum. The higher frequency of intrautero transmission was statistically significant (P = 0.001). Use of antiretrovirals (ARVs) in the three stages of gestation was a protective risk factor for MTCT (PR = 0.42; CI: 0.21-0.83; P = 0.013). A higher HIV viral load at delivery was the only independent risk factor for MTCT. Early and universal access to ARVs during pregnancy are the most important measures to decrease vertical HIV-1 transmission even in areas where HIV clade distribution differs.
authors.affiliation: Universidade Federal do Rio Grande, Rio Grande do Sul, Brazil.
authors.forename: M
authors.initials: M
authors.lastname: Tornatore
authors.forename: C V
authors.initials: CV
authors.lastname: Gonçalves
authors.forename: R A
authors.initials: RA
authors.lastname: Mendoza-Sassi
authors.forename: J M
authors.initials: JM
authors.lastname: Silveira
authors.forename: N E
authors.initials: NE
authors.lastname: D'ávila
authors.forename: C G
authors.initials: CG
authors.lastname: Maas
authors.forename: M S
authors.initials: MS
authors.lastname: Bianchi
authors.forename: E M
authors.initials: EM
authors.lastname: Pinheiro
authors.forename: E S
authors.initials: ES
authors.lastname: Machado
authors.forename: M A
authors.initials: MA
authors.lastname: Soares
authors.forename: A M B
authors.initials: AM
authors.lastname: Martinez
mesh_terms: D000328:Adult; D044966:Anti-Retroviral Agents / Q000627:therapeutic use; D001938:Brazil; D005260:Female; D015700:HIV Envelope Protein gp41 / Q000235:genetics; D015658:HIV Infections / Q000635:transmission*; D015497:HIV-1; D006801:Humans; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control; D008297:Male; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D019562:Viral Load
chemical_list: D044966:Anti-Retroviral Agents; D015700:HIV Envelope Protein gp41; C514787:gp41 protein, Human immunodeficiency virus 1