Elevated risk for HIV-1 infection in adolescents and young adults in São Paulo, Brazil.
BACKGROUND
Recent studies have sought to describe HIV infection and transmission characteristics around the world. Identification of early HIV-1 infection is essential to proper surveillance and description of regional transmission trends. In this study we compare people recently infected (RI) with HIV-1, as defined by Serologic Testing Algorithm for Recent HIV Seroconversion (STARHS), to those with chronic infection.


RESULTS
Subjects were identified from 2002-2004 at four testing sites in São Paulo. Of 485 HIV-1-positive subjects, 57 (12%) were defined as RI. Of the participants, 165 (34.0%) were aware of their serostatus at the time of HIV-1 testing. This proportion was statistically larger (p<0.001) among the individuals without recent infection (n = 158, 95.8%) compared to 7 individuals (4.2%) with recently acquired HIV-1 infection. In the univariate analysis, RI was more frequent in <25 and >59 years-old age strata (p<0.001). The majority of study participants were male (78.4%), 25 to 45 years-old (65.8%), white (63.2%), single (61.7%), with family income of four or more times the minimum wage (41.0%), but with an equally distributed educational level. Of those individuals infected with HIV-1, the predominant route of infection was sexual contact (89.4%), with both hetero (47.5%) and homosexual (34.5%) exposure. Regarding sexual activity in these individuals, 43.9% reported possible HIV-1 exposure through a seropositive partner, and 49.4% reported multiple partners, with 47% having 2 to 10 partners and 37.4% 11 or more; 53.4% of infected individuals reported condom use sometimes; 34.2% reported non-injecting, recreational drug use and 23.6% were reactive for syphilis by VDRL. Subjects younger than 25 years of age were most vulnerable according to the multivariate analysis.


CONCLUSIONS
In this study, we evaluated RI individuals and discovered that HIV-1 has been spreading among younger individuals in São Paulo and preventive approaches should, therefore, target this age stratum.
Bassichetto
Katia Cristina
KC
Public Health Department of São Paulo, São Paulo, Brazil. kbassichetto@prefeitura.sp.gov.br
Bergamaschi
Denise Pimentel
DP
Oliveira
Solange Maria
SM
Deienno
Marylei Casteldelli Verri
MC
Bortolato
Reginaldo
R
de Rezende
Heloíza Vilma
HV
Arthur
Thaís
T
Tomiyama
Helena
H
Watkins
Colyn
C
Mesquita
Fabio
F
Abbate
Maria Cristina
MC
Kallas
Esper Georges
EG
D000293:Adolescent; D000328:Adult; D001938:Brazil / Q000453:epidemiology; D005260:Female; D015658:HIV Infections / Q000453:epidemiology*; D015497:HIV-1 / Q000302:isolation & purification; D006801:Humans; D008297:Male; D012307:Risk Factors