Recent dengue virus infection: epidemiological survey on risk factors associated with infection in a medium-sized city in Mato Grosso

ABSTRACT BACKGROUND: Dengue is considered to be the most important arbovirus worldwide, with important complications that increase its lethality. In Brazil, an endemic country, the disease reaches significant incidence levels, with occurrences of serious cases and high costs of hospitalizations for its treatment. OBJECTIVE: To analyze risk factors among individuals with recent histories of dengue infection in a medium-sized city in Mato Grosso. DESIGN AND SETTING: Descriptive cross-sectional study, of epidemiological-survey type, conducted among the urban population of a city located in mid-northern Mato Grosso. METHODS: A seroepidemiological survey using questionnaires and collection of biological material was conducted among 596 adults aged ≥ 18 years who had been selected through a cluster sampling process. Positive dengue cases were those with positive results from anti-dengue immunoassays (ELISA). Statistical analyses with descriptive and inferential techniques were used, with 95% confidence intervals and a 5% significance level. RESULTS: The seroepidemiological profile of the study participants was predominantly female, with ages between 18 and 39 years, self-declared non-white race/color, not more than eight years of education and not living with a companion. Among the sanitary factors analyzed, the following were risk factors for dengue virus infection: no running water at home; no water supply from the public piped network; no waste from drains or toilets sent to the sewage network; endemic disease combat agents visiting the home; and presence of mosquito breeding sites at home. CONCLUSION: Low schooling levels and previous dengue virus infection were associated with current dengue virus infection.

Recent dengue virus infection: epidemiological survey on risk factors associated with infection in a medium-sized city in Mato Grosso.

BACKGROUND: Dengue is considered to be the most important arbovirus worldwide, with important complications that increase its lethality. In Brazil, an endemic country, the disease reaches significant incidence levels, with occurrences of serious cases and high costs of hospitalizations for its treatment. OBJECTIVE: To analyze risk factors among individuals with recent histories of dengue infection in a medium-sized city in Mato Grosso. DESIGN AND SETTING: Descriptive cross-sectional study, of epidemiological-survey type, conducted among the urban population of a city located in mid-northern Mato Grosso. METHODS: A seroepidemiological survey using questionnaires and collection of biological material was conducted among 596 adults aged ≥ 18 years who had been selected through a cluster sampling process. Positive dengue cases were those with positive results from anti-dengue immunoassays (ELISA). Statistical analyses with descriptive and inferential techniques were used, with 95% confidence intervals and a 5% significance level. RESULTS: The seroepidemiological profile of the study participants was predominantly female, with ages between 18 and 39 years, self-declared non-white race/color, not more than eight years of education and not living with a companion. Among the sanitary factors analyzed, the following were risk factors for dengue virus infection: no running water at home; no water supply from the public piped network; no waste from drains or toilets sent to the sewage network; endemic disease combat agents visiting the home; and presence of mosquito breeding sites at home. CONCLUSION: Low schooling levels and previous dengue virus infection were associated with current dengue virus infection.

Serological evidence of Bartonellosis in an indigenous community in the Brazilian Legal Amazonia.

BACKGROUND: Due to immunological susceptibility, close contact with the environment and way of life, indigenous communities are in a highly vulnerable condition to be affected by zoonoses, such as bartonellosis. METHODS: Seventy three paired serum samples were collected from indigenous people from a region of the Brazilian Legal Amazon, in cohorts carried out in 2014 and 2015, with the performance of serological tests by indirect immunofluorescence to detect anti-Bartonella IgG antibodies. The interviews and laboratory results were double entered in the EpiInfo 7 software, and the data processing was performed in the MiniTab 17 software. RESULTS: 5.47% of the indigenous people were seroreagent. The female gender was predominant (65.75%), aged between 20 and 39 years old (39.73%) with complete elementary school (42.47%). As for housing, wooden residences predominated (50.68%). Rodents were seen by 46.58% of the interviewees, and 55.88% of them reported that the animal was close to or inside the house. It was identified that each indigenous family, in its majority, had four to six cats, for the function of hunters of rodents. CONCLUSION: The high concentration of domestic cats, the close contact of indigenous people with wild rodents and the lack of care and poor hygiene of both are aspects that imply the possibility of infection by Bartonella sp. Health surveillance through seroepidemiological studies is essential to find evidence of the circulation of bartonellosis in these populations.