Yellow fever outbreak in a rural-urban mixed community of Espírito Santo, Brazil: epidemiological aspects

Objective. To describe the epidemiological aspects of an outbreak of yellow fever (YF) that occurred in the state of Espírito Santo, Brazil, from 1 January 2017 – 31 July 2017. Methods. A descriptive, quantitative, retrospective approach analyzed secondary data obtained from the national notification systems, Information System of Diseases Notifications (SINAN), Laboratory Environment Manager (GAL), and the Espírito Santo Health Secretariat (SESA). Results. From 1 January 2017 – 8 July 2017, a total of 824 cases were reported in Espírito Santo, 307 (37%) of which were confirmed as YF. Of these, 95 (30.9%) died from the disease. Men were those most affected, corresponding to 244 (79.5%) cases, and women to 63 (20.5%) cases. The greatest incidence rate registered was in the city of Santa Leopoldina (380.2 cases/100 000 inhabitants). The outbreak evolved rapidly and a response was possible due to a multidisciplinary group created specifically to tackle the YF outbreak. Conclusions. The data were received and analyzed quickly and the response, consisting of immediate treatment of the cases and a blocking vaccination strategy, was developed to halt the progression of this fatal disease. In spite of these efforts, the case fatality rate of yellow fever remained high

First isolation of West Nile virus in Brazil

BACKGROUND Serological evidence of West Nile virus (WNV) infection has been reported in different regions of Brazil from equine and human hosts but the virus had never been isolated in the country. OBJECTIVES We sought to identify the viral etiology of equine encephalitis in Espírito Santo state. METHODS We performed viral culture in C6/36 cells, molecular detection of WNV genome, histopathology and immunohistochemistry from horse cerebral tissue. We also carried out sequencing, phylogenetic analysis and molecular clock. FINDINGS Histopathologic analysis from horse cerebral tissue showed injury related to encephalitis and WNV infection was confirmed by immunohistochemistry. The virus was detected by reverse transcription quantitative polymerase chain reaction (RT-qPCR) from brain tissue and subsequently isolated in C6/36 cells. WNV full-length genome was sequenced showing the isolated strain belongs to lineage 1a. The molecular clock indicated that Brazilian WNV strain share the same common ancestor that were circulating in US during 2002-2005. MAIN CONCLUSIONS Here we report the first isolation of WNV in Brazil from a horse with neurologic disease, which was clustered into lineage 1a with others US WNV strains isolated in beginning of 2000’s decade