Dados do Trabalho

Título

Density of Culex quinquefasciatus associated with socio-environmental conditions in a municipality with indeterminate transmission for lymphatic filariasis in the northeastern region of Brazil

Introdução

Lymphatic filariasis (LF) is a neglected tropical disease transmitted by mosquitoes and associated with poverty and poor environmental conditions. With the inclusion of vector control activities in LF surveillance actions, there is a need to develop simple methods to identify areas with higher mosquito density and consequent risk of W. bancrofti transmission. 

Objetivo (s)

The objective of this study was to analyze the spatial distribution of C. quinquefasciatus density according to socio-environmental conditions in an area with undetermined transmission of W. bancrofti. 

Material e Métodos

An ecological study was conducted, with the unit of analysis being the urban census tracts of Igarassu in the Metropolitan Region of Recife, Pernambuco, northeastern Brazil. The mosquitoes were captured in 2,060 houses distributed across 117 census tracts. The vector density index (VDI) was constructed, that measures the average number of lymphatic filariasis transmitting mosquitoes per number of houses collected in the risk stratum. Moreover, the social deprivation indicator (SDI) was constructed and was carried out through principal component factor analysis. The study was approved by the Research Ethics Committee of the Instituto Aggeu Magalhães, FIOCRUZ - PE, under approval number 039627/2019. The study was supported by the Fundação de Apoio à Fiocruz (Fiotec) - Finace Code: VPPCB-007-FIO-18-2-107.

Resultados e Conclusão

There was a statistically significant correlation among seven eligible variables for forming the SDI. To create the SDI strata, was chosen strata 1, 2, and 3 (very low risk, low risk, and medium risk) that were not statistically significant. Stratum 4 (high risk) was statistically significant. The average number of female C. quinquefasciatus found in the high-risk stratum was 242, while the low-risk stratum had an average of 108. The overall VDI was 6.8 mosquitoes per household. The VDI for the high-risk stratum was 13.2 mosquitoes per household, while for the low/medium-risk stratum, it was 5.2. Rapidly and cost-effectively detecting areas indicated for vector control can be highly valuable for health services. Thus, this study offers an SDI for the density of C. quinquefasciatus mosquitoes, which reduces the cost associated with data collection and allows for indicating priority areas for vector control actions.

Palavras Chave

Lymphatic filariasis; Culex quinquefasciatus; vector density index; social deprivation indicator