Infecção por Zika vírus, precipitação pluviométrica e fatores socioeconômicos em Mato Grosso, 2016

Abstract

The Zika virus (ZIKV) is an arbovirus, flavivirus of the Flaviviridae family, with two lines described so far: African and Asian. The ZIKV, discovered in 1947 in Uganda, is mainly transmitted by mosquitoes in the genus Aedes. The incidence of ZIKV may be related to factors resulting from human activity in the environment, such as deforestation, increasing urbanization, low socioeconomic levels, and also related to a natural factor such as rapid climate change. In 2015, Brazil recorded the first autochthonous human cases of ZIKV, confirming the recent entry of this arbovirus in the country. In the year 2016, Mato Grosso registered incidence of 704 cases per 100,000 inhabitants, being at an alarming risk. In addition to the high incidence in the state, 85 municipalities were classified with high risk of the disease. Among the symptoms caused by the ZIKV infection are low fever, maculopapular rash, arthralgia, myalgia, headache and conjunctival hyperemia. ZIKV infection is also related to cases of fetal microcephaly and neurological complications in adults. This study aimed to analyze the incidence of Zika virus infection, socioeconomic factors and rainfall in Mato Grosso, in the year 2016. This is an ecological study. The notified case data will be collected from the SINAN Information System, provided by the State Health Department of Mato Grosso, data on socioeconomic conditions will be collected from the Firjan Municipal Development Index (FMDI) and the rainfall data will be collected from the Tropical Rainfall Measuring Mission (TRMM) information base. In the first manuscript presented in this dissertation, the clusters of space-time risk for ZIKV infection were identified. It was identified that the highest occurrence of cases was concentrated between the 1st to 13th Epidemiological Week (SE), with reports falling in the following weeks. The high-risk primary clusters were located in the North and Northeast-Matogrossense mesoregions. The municipalities of Agua Boa and Nova Mutum, located in the central region of the state, presented the highest relative risks (RR) in the periods analyzed. In the second manuscript, it was observed that the highest incidence occurred during the summer in the state, marked by high temperatures and higher volume of rainfall. However, when correlating these variables with different times lag, it was observed that the associations are weak. Regarding socioeconomic factors, the municipalities with ZIKV infection rates above the state rate had higher rates than those with rates below the state average, and there appeared to be no relation between cases of the disease and socioeconomic indexes. In summary, to control the disease, it is imperative that intersectoral actions that transcend the exclusive actions of chemical control of the vector are agreed upon. Thus, health sector initiatives should be integrated with other segments, such as education, housing, basic sanitation, solid waste and urban planning.