The municipality of Londrina ranks second in the number of AIDS cases in the state of Paraná, Brazil, with the Ministry of Health notified of 1070 cases from 1984 to 2002. The aim of this study was to determine the seroprevalence and risk factors for HTLV-1/2 infection in HIV-infected patients attending the AIDS Reference Center serving Londrina (and surrounding region), Paraná, Brazil. Data concerning sociodemographic conditions and risk factors were collected from 784 HIV-infected patients, using a questionnaire. Blood samples were obtained from 758 of the patients and subjected to serologic screening tests for the determination of HTLV-1/2, as well as hepatitis B virus (HBV), hepatitis C virus (HCV), and syphilis. Most patients were white (mean age, 35.9 years); 55.9% were males and 44.1% were females. The most frequent sexually transmitted disease was gonorrhea (28.5%), followed by syphilis (14.3%) and condyloma (12.2%). The major risk factors associated with the acquisition of retroviruses were sexual contact (84.8%) and intravenous drug use (IDU, 11.9%). The overall infection seroprevalence was 6.4% for HTLV-1/2, 37.2% for HBV, 21.0% for HCV, and 24.4% for syphilis. HTLV-1 and HTLV-2 infections were confirmed in 0.8 and 4.9% of patients, respectively. HIV/HTLV-1/2 coinfection was more frequent in IDUs (59.2% of cases) and was strongly associated with HCV (22.60 [95% CI, 10.35-49.35]). A weak association with HBV (2.09 [95% CI, 1.13-3.90]) and no association with syphilis were observed. The results showed that human retroviruses are circulating in southern Brazil, mainly among white people of both genders of low socioeconomic conditions and educational level. Although the sexual route was considered to be the major risk factor for HIV infection, HTLV-1/2 infection was strongly associated with IDU.

The current diagnosis of human T-lymphotropic virus type-2 (HTLV-2) infection is based on the search of specific antibodies; nevertheless, several studies conducted in Brazil pointed deficiencies of the commercially available kits in detecting HTLV-2, mostly in HIV/AIDS patients. This study searched for the presence of HTLV-1 and -2 in 758 HIV/AIDS patients from Londrina, Paraná, Brazil. Serum samples were screened for HTLV-1/2 antibodies using two EIA kits (Vironostika and Murex), and confirmed by WB (HTLV Blot 2.4, Genelabs). The results obtained by EIA disclosed 49 (6.5%) reactive sera: 43 positive by both EIA kits, and six with discordant results. WB confirmed HTLV-1 infection in seven samples (0.9%) and HTLV-2 in 21 sera (2.8%). Negative and indeterminate results were detected in four (0.5%) and 16 (2.1%) sera, respectively. Blood from 47 out of 49 HTLV seroreactive patients were collected and analyzed for the presence of env, LTR and tax genomic segments of HTLVs by PCR. PCR confirmed six cases of HTLV-1 and 37 cases of HTLV-2 infection (14 out of 16 that were found to be WB indeterminate). Restriction analysis of the env PCR products of HTLV-2 disclosed 36 isolates of HTLV-2a/c subtype, and one of HTLV-2b subtype. These results emphasize the need of improving serologic tests for detecting truly HTLV-2 infected patients from Brazil, and confirm the presence of HTLV-2b subtype in the South of this country.

The ability to control human immunodeficiency virus type 1 (HIV-1) infection and progression of the disease is regulated by host and viral factors. This cross-sectional study describes the socio-demographic and epidemiological characteristics associated with HIV-1 infection in 1,061 subjects attended in Londrina and region, south of Brazil: 136 healthy individuals (Group 1), 147 HIV-1-exposed but uninfected individuals (Group 2), 161 HIV-1-infected asymptomatic patients (Group 3), and 617 patients with AIDS (Group 4). Data were obtained by a standardized questionnaire and serological tests. The age of the individuals ranged from 15.1 to 79.5 years, 54.0% and 56.1% of the Groups 3 and 4 patients, respectively, were men. The major features of groups 2, 3, and 4 were a predominance of education level up to secondary school (55.8%, 60.2% and 62.4%, respectively), sexual route of exposure (88.4%, 87.0% and 82.0%, respectively), heterosexual behavior (91.8%, 75.2% and 83.7%, respectively), and previous sexually transmitted diseases (20.4%, 32.5%, and 38.1%, respectively). The patients with AIDS showed the highest rates of seropositivity for syphilis (25.6%), of anti-HCV (22.3%), and anti-HTLV I/II obtained by two serological screening tests (6.2% and 6.8%, respectively). The results documenting the predominant characteristics for HIV-1 infection among residents of Londrina and region, could be useful for the improvement of current HIV-1 prevention, monitoring and therapeutic programs targeted at this population.

Abstract. The frequency of CCR5-Δ32 allele in human immunodeficiency virus type 1 (HIV-1) infection in the southern Brazilian population was determined in a crosssectional study carried out from

The interaction of viral and host factors is believed to determine not only the risk for initial human immunodeficiency virus type 1 (HIV-1) acquisition but also the course of the infection. Genetic polymorphisms in the chemokine receptors and their ligands were related to the susceptibility and resistance to HIV-1 infection. A polymorphism in the conserved 3' untranslated region of the stromal cell-derived factor-1 (SDF1) gene, which encodes a ligand of the CXCR4 receptor, has been related either to delayed progression to AIDS or to rapid disease progression and death. Global, regional, and ethnic distributions of frequencies of SDF1 genotypes and of the SDF1-3'A allele vary significantly. Although the HIV-1 epidemic is increasing in Brazil, little information about the frequencies of host genetic mutations related to HIV/AIDS resistance in the Brazilian population has been reported. To address this question, this study was carried out in order to determine the frequencies of the SDF1 polymorphism and the SDF1-3'A allele on 1061 genomic DNA samples purified from peripheral blood cells of 136 healthy individuals (group 1), 147 HIV-1-exposed seronegative individuals (group 2), 161 HIV-1-infected asymptomatic individuals and with CD4(+) T-cells count 350 mm(-3) (group 3), and 617 HIV-1-infected individuals with AIDS and/or CD4(+) T-cells count < 350 mm(-3) (group 4). The frequencies of the SDF1-3'A homozygous mutation were 3.7%, 6.1%, 4.3%, and 5.3% among groups 1, 2, 3, and 4, respectively (P = 0.5120). The overall frequency of the SDF1-3'A allele was 0. 1984 and did not differ among the four groups (P = 0.2744). The results underscore the global distribution of the SDF1 polymorphism and the hypothesis that the SDF1-3'A allele, itself, may not be sufficient to prevent the risk of HIV-1 infection and may be not related to the progression of the disease in the Brazilian population.