Dengue Fever and Aedes aegypti in indigenous Brazilians: seroprevalence, risk factors, knowledge and practices.

OBJECTIVE: Dengue remains an important public health problem in Brazil. We estimated the associated factors of dengue seroprevalence among native Indians of the Tremembé ethnic and their knowledge about the aspects related to the presence of mosquitoes of the genus Aedes. METHODS: An analytical cross-sectional study and a prospective environmental study to monitor the trapping of mosquito eggs monthly were performed. The serological portion of the study involved indigenous people living in the village of Tapera in northeastern Brazil. Ovitraps were monitored for 12 months. RESULTS: Two hundred and ninety of 350 indigenous people (82.9%) participated in the study, with an average age of 30.2 years. The seroprevalence was 22.1% and positivity increased with age, with rates of 4.2% in children under 15 years of age, 26.8% in 15 to 59-year-olds and 42.3% in those older than 59 (CI: 2.25-15.96; P < 0.001). A higher incidence of moving to the city and the presence of underlying diseases were associated with the occurrence of dengue (P < 0.001). Four serotypes were detected, with the highest prevalence of DENV-1 (77.8%), followed by DENV-2 (70.4%), DENV-3 (14.8%) and DENV-4 (11.1%). Eggs were collected in all months of the year and in the traps located in the vicinities of the domiciles (57%). CONCLUSIONS: We present the first seroepidemiological survey of dengue conducted among indigenous populations in Brazil. This lack of studies is likely due to the great bureaucratic challenge of working with indigenous populations, which may lead to greater negligence in the health of these populations.

Death by dengue fever in a Brazilian child: a case report.

BACKGROUND: Dengue is an important worldwide public health problem, and continues to spread in Brazil. This article presents the first Brazilian case report of the death of an indigenous child by dengue fever. CASE PRESENTATION: In August 2013, a child aged 2 years and from the Tremembé ethnic group, who was previously healthy with no complaints, suddenly presented intense crying, precordial pain, and general malaise. A few minutes after these non-specific symptoms, the patient started tonic-clonic convulsions and had cyanosis, a substantial increase in body temperature to the touch, cold sudoresis, sphincter relaxation, and unconsciousness. This situation remained for 15 minutes, progressing to respiratory insufficiency, with consequent absence of peripheral pulses. Death was confirmed approximately 40 minutes after the first symptoms. An autopsy was performed using the usual techniques. Immunohistochemistry was positive for dengue, and microscopic examination indicated micro perivascular edema and cerebral hemorrhage. CONCLUSION: Considering that the death occurred during the major endemic seasonal period for dengue fever, primary clinical evidence suggestive of viral infection presenting with sudden and quick death, and positive immunohistochemistry results, the case was closed as severe dengue fever. Clinicians must consider dengue as a diagnostic hypothesis among the indigenous population in Brazil.