Spotted fever outbreak with cases and deaths in the same family in a municipality in south eastern Brazil, 2019

Abstract

Background: Brazilian Spotted Fever (BSF) is a highly lethal hemorrhagic febrile infectious disease whose etiological agent is the bacterium Rickettsia rickettsii, transmitted by the Amblyomma sculptum tick. Between May and June/2019 there was an outbreak of the disease in the municipality of Contagem, state of Minas Gerais, with previous identification of Rickettsia rickettsia in 2017. The objectives were to investigate the outbreak, describe cases and deaths and raise hypotheses for illness. Methods and materials: Was conducted a descriptive study, with a semi-structured questionnaire from May to June/2019. The population was individuals attended or notified by Contagem municipality as a possible exposed to the probable site of infection. Suspected Cases were individual with fever, headache, myalgia who reported tick bite and/or contact with domestic and/or wild animals and/or visited known area with transmission of BSF from April 28 to June/02, 2019. Confirmed cases were individuals with laboratory confirmation for BSF by Polymerase Chain Reaction. Results: Among the 10 individuals that attended to the suspected case definition, five were confirmed and four died (80% lethality). Median age of the cases were 40 years, four male and all had fever, myalgia and headache; three manifested rash and petechiae; four participated together in a weeding activity and three related tick bite. All deaths happened in the same family and had dengue as the first diagnostic hypothesis; three of these had first health assistance in a private medium complexity service and a seven days median between symptoms and death. Conclusion: There was a high lethality outbreak, with cases and deaths in the same family, possibly related to a weeding activity in a preserved forest area where cases developed all classic symptoms of the disease. It's recommended cleaning and maintenance routines in public spaces with grass and vegetation; local professionals training for the need to investigate BSF in the health assistance routine; investigation and diagnostic capacity increase for BSF and intensification of educational actions aimed in the transmission mode, disease control and prevention.