Estimated incidence and genotypes of HIV-1 among pregnant women in central Brazil.
OBJECTIVE
To estimate the incidence of HIV-1 infection among pregnant women from central-western Brazil.


METHODS
Observational cross-sectional study.


METHODS
A total of 54,139 pregnant women received antenatal HIV screening from a network of public healthcare centers in 2011. The incidence of confirmed HIV-1 infection was estimated using the Serological Testing Algorithms for Recent HIV Seroconversion (STARHS) methodology and BED-capture enzyme immunoassay (BED-CEIA). The yearly incidence was calculated, and adjusted incidence rates were estimated. For a subgroup of patients, protease and partial reverse transcriptase regions were retrotranscribed from plasma HIV-1 RNA and sequenced after performing a nested polymerase chain reaction.


RESULTS
Of the participants, 20% had a pregnancy before the age of 18 and approximately 40% were experiencing their first pregnancy. Of the 54,139 pregnant women screened, 86 had a confirmed HIV-1 diagnosis, yielding an overall prevalence of 1.59 cases per 1000 women (95% CI 1.27-1.96). A higher prevalence was detected in the older age groups, reflecting cumulative exposure to the virus over time. Among the infected pregnant women, 20% were considered recently infected according to the BED-CEIA. The estimated incidence of HIV infection was 0.61 per 1000 person-years (95% CI 0.33-0.89); the corrected incidence was 0.47 per 1000 person-years (95% CI 0.26-0.68). In a subgroup of patients, HIV-1 subtype C (16.7%) was the second most prevalent form after subtype B (66.7%); BF1 recombinants (11.1%) and one case of subtype F1 (5.5%) were also detected.


CONCLUSIONS
This study highlights the potential for deriving incidence estimates from a large antenatal screening program for HIV. The rate of recent HIV-1 infection among women in their early reproductive years is a public health warning to implement preventive measures.
Faculty of Medicine, Federal University of Goias, Goias, Brazil.
Zelma Bernardes
ZB
Costa
Mariane Martins de Araujo
MM
Stefani
Yanna Andressa Ramos
YA
de Lima
Wayner Vieira
WV
de Souza
Noemia Teixeira
NT
de Siqueira Filha
Marilia Dalva
MD
Turchi
Walter Costa
WC
Borges
Clidenor Gomes
CG
Filho
Jose Vicente Macedo
JV
Filho
Ana Lucia
AL
Minuzzi
Celina Maria Turchi
CM
Martelli
D015492:AIDS Serodiagnosis / Q000379:methods; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001938:Brazil / Q000453:epidemiology; D002648:Child; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005838:Genotype; D015658:HIV Infections / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology*; D015497:HIV-1 / Q000145:classification / Q000235:genetics*; D006801:Humans; D015994:Incidence; D008403:Mass Screening / Q000379:methods*; D010802:Phylogeny; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000175:diagnosis / Q000453:epidemiology* / Q000821:virology; D015995:Prevalence; D055815:Young Adult; D054302:pol Gene Products, Human Immunodeficiency Virus / Q000235:genetics
D054302:pol Gene Products, Human Immunodeficiency Virus