Dados do Trabalho

Título

Risk factor of Zika sexual transmission in two urban setting of Brazil

Introdução

  The Zika virus was first reported in March 2015 in Camaçari, a city in the state of Bahia, and in Natal, the state capital of Rio Grande do Norte. Following these initial reports, other cities in Bahia state quickly reported Zika cases, including the capital city of Salvador, which accounted for about 90% of all notified Zika virus (ZIKV) cases in Brazil that year. The public health services (Sistema Único de Saúde - SUS) in Bahia state were overwhelmed due to the concurrent Chikungunya virus (CHIKV) epidemic. In this study, we examine the Zika outbreak in two cities: Feira de Santana and Salvador. Feira de Santana is an urban center in Brazil, located approximately 100 km from Salvador, the capital of Bahia. The South American epidemic was declared a public health emergency by the World Health Organization (WHO) in 2016. While the Zika virus is primarily transmitted through the bite of an infected Aedes mosquito, it can also be transmitted sexually. This mode of transmission is significant as it broadens the potential spread of the virus beyond the traditional vector-borne pathway.  

Objetivo (s)

Our main goal is to estimate the risk of sexual transmission during the 2015 Zika virus outbreak in Feira de Santana and Salvador, Brazil. In this study, we calculate the sexual transmission risk for ZIKV using the basic reproduction number, R0, estimated from the notification data of these cities.  

Material e Métodos

Our primary objective is to assess the risk of sexual transmission during the 2015 Zika virus outbreak in Feira de Santana and Salvador, Brazil. To achieve this, we estimate the basic reproduction number (R0) using notification data from the Sistema de Informações de Agravos de Notificação (SINAN) for these cities. We employ the methodology proposed by Pinho et al. to calculate R0. Additionally, for the analysis of sexual transmission, we utilize an analytical expression developed by Cruz-Pacheco et al., derived from a recent mathematical model they proposed.  

Resultados e Conclusão

We evaluated the rates of sexual and vector transmission of ZIKAV in Salvador city, revealing that this rate is approximately twice as high as our estimate for Feira de Santana. Our findings emphasize the crucial role of sexual transmission in the disease's spread, highlighting the pressing need for public health policies to address it. Our findings emphasize the crucial role of sexual transmission in the disease's spread, highlighting the pressing need for public health policies to address it.

Palavras Chave

Zika Vírus; Basic reproduction number; sexual transmission