Seroprevalence of Chikungunya virus and living conditions in Feira de Santana, Bahia-Brazil.

Background: Chikungunya is an arbovirus, transmitted by Aedes mosquitoes, which emerged in the Americas in 2013 and spread rapidly to almost every country on this continent. In Brazil, where the first cases were detected in 2014, it currently has reached all regions of this country and more than 900,000 cases were reported. The clinical spectrum of chikungunya ranges from an acute self-limiting form to disabling chronic forms.

The spatiotemporal trajectory of a dengue epidemic in a medium-sized city.

Understanding the transmission dynamics of infectious diseases is important to allow for improvements of control measures. To investigate the spatiotemporal pattern of an epidemic dengue occurred at a medium-sized city in the Northeast Region of Brazil in 2009, we conducted an ecological study of the notified dengue cases georeferenced according to epidemiological week (EW) and home address. Kernel density estimation and space-time interaction were analysed using the Knox method.

Arterial hypertension and skin allergy are risk factors for progression from dengue to dengue hemorrhagic fever: a case control study.

Background: Currently, knowledge does not allow early prediction of which cases of dengue fever (DF) will progress to dengue hemorrhagic fever (DHF), to allow early intervention to prevent progression or to limit severity. The objective of this study is to investigate the hypothesis that some specific comorbidities increase the likelihood of a DF case progressing to DHF.

Methods: A concurrent case-control study, conducted during dengue epidemics, from 2009 to 2012.

Dengue hemorrhagic fever is associated with polymorphisms in JAK1.

To identify genes associated with the clinical presentation of dengue, 50 cases of probable or possible dengue hemorrhagic fever (DHF), 236 dengue fever (DF), and 236 asymptomatic infections were genotyped for 593 single-nucleotide polymorphisms (SNPs) in 56 genes across the type 1 interferon (IFN) response pathway as well as other important candidate genes. By single locus analysis comparing DHF with DF, 11 of the 51 markers with P<0.05 were in the JAK1 gene.

Allergies and diabetes as risk factors for dengue hemorrhagic fever: results of a case control study.

Background: The physiopathology of dengue hemorrhagic fever (DHF), a severe form of Dengue Fever, is poorly understood. We are unable to identify patients likely to progress to DHF for closer monitoring and early intervention during epidemics, so most cases are sent home. This study explored whether patients with selected co-morbidities are at higher risk of developing DHF.

[Progression of dengue virus circulation in the State of Bahia, Brazil, 1994-2000].

Introduction: The strength of the re-emergence of dengue virus and the severity of these infections put this disease in the priority agenda of the institutions responsible for protecting the health of populations. Important for understanding the epidemiology of dengue nowadays refers to the knowledge of the patterns of spatial-temporal diffusion, though there is few research addressing this issue. This study describes the process of dissemination of dengue in the state of Bahia, from 1994 to 2000.

Genetic ancestry and income are associated with dengue hemorrhagic fever in a highly admixed population.

To test whether African ancestry is protective for severe dengue, we genotyped 49 hospitalized cases of dengue hemorrhagic fever (DHF) as well as 293 neighborhood cases of dengue fever and 294 asymptomatic controls in Salvador, Bahia, Brazil. Ancestry-informative markers and 282 unlinked SNPs not associated with the clinical presentation of dengue were used to estimate ancestry. After controlling for income, both self-defined Afro-Brazilian ethnicity and African ancestry were protective for DHF (P=0.

Infestation of Aedes aegypti estimated by oviposition traps in Brazil.

Objective: To assess infestation levels of Aedes aegypti using the oviposition trap (ovitrap) method and to compare these results with data obtained with the use of indices traditionally applied in public programs aimed at fighting this vector.

Methods: Nine sentinel areas in Northeastern, Brazil, were assessed and infestation levels were measured for a nine-month period. Egg density and container indices were estimated and compared with previous results found using the house index and Breteau index.