Prevalence and Risk Factors for HTLV-1/2 Infection in Quilombo Remnant Communities Living in the Brazilian Amazon.

Human T-lymphotropic viruses 1 and 2 (HTLV-1 and HTLV-2) are retroviruses that originated on the African continent and dispersed throughout other continents through human migratory flows. This study describes the prevalence of HTLV-1 and HTLV-2 infection in residents of 11 quilombo remnant communities in the state of Pará, Brazil, and the associated risk factors. A total of 859 individuals (334 men and 525 women), aged between 7 and 91 years, participated in the study. All subjects answered a questionnaire with questions on sociodemographic characteristics and on risk factors associated with HTLV infection, and blood samples were collected and separated into plasma and leukocytes. An immunoenzymatic assay (ELISA; Murex HTLV-I+II, DiaSorin, Dartford, UK) was used as a screening test, and positive samples were subjected to line immunoassay confirmatory tests (Inno-LIA HTLV I/II Score FUJIREBIO) and DNA extraction for subsequent real-time PCR to differentiate the viral type. Four of the 859 individuals were seropositive for HTLV. HTLV-1 infection was confirmed in one individual from the Itamoari community (0.92%), and HTLV-2 infection was confirmed in two individuals from São Benedito (3.17%) and in one individual from Arimandeua (2.22%). Blood transfusion was the only risk factor associated with HTLV infection in this study. This study reports the occurrence of HTLV-1 and HTLV-2 in quilombo remnant communities in the state of Pará. Considering the African origin of the virus and its introduction into Brazil from the slave trade, the continued evaluation of quilombola communities in the state of Pará is essential to better characterize the distribution of infections in these populations and to create public health policies for the control of the spread of the virus and associated diseases.

Long-lasting insecticide-treated nets (LLINs) used to reduce the incidence of malaria in a municipal district of the Brazilian Amazon

Malaria is still the parasitic disease with the greatest worldwide impact. Recently in Brazil, almost all cases of the disease have been recorded in the Amazon region. The struggle against the vectors through insecticide treated nets associated with rapid diagnosis and treatment, is currently the main strategy. This study aimed to determine the protective effect of these devices on the incidence of malaria in one municipality in the Amazon, and was conducted with information from the Brazilian Ministry of Health and with the analysis of 10,050 slides of thick blood smears that were prepared and examined in loco. The Shapiro-Wilk test was used to determine the normality of the data and the Mann-Whitney test was used for all comparisons of the analyzed variables. The significance level was set at p≤0.01. The results revealed a significant reduction in the number of malaria cases in all analyzed variables, including the species of the parasite, the level and type of infection, and the gender and age of the diagnosed individual (p˂0.01). These findings confirmed that these devices are an important tool for disease control, presenting a new variable in combating the disease in the studied population. Therefore, the use of insecticide-treated nets is recommended as a preventive measure and guidance to the population regarding the correct way to use this device is required to avoid problems such as the loss of naturally acquired immunity, reduction in the protective effect of the device and the development of resistance to the insecticide.