Congenital Zika syndrome and living conditions in the largest city of northeastern Brazil

Souza et al. BMC Public Health (2022) 22:1231

https://doi.org/10.1186/s12889-022-13614-x

RESEARCH

Congenital Zika syndrome and living

conditions in the largest city of northeastern

Brazil

Marcos Paulo Almeida Souza1,2*†, Márcio Santos da Natividade1†, Guilherme Loureiro Werneck3,4† and

Darci Neves dos Santos1†

Abstract

Background: The Zika virus (ZIKV) epidemic hit Brazil in 2015 and resulted in a generation of children at risk of

congenital Zika syndrome (CZS). The social vulnerability of certain segments of the population contributed to the

disproportional occurrence of CZS in the Brazilian Northeast, the poorest region in the country. Living conditions

are essential factors in understanding the social determination of CZS, which is embedded in a complex interaction

between biological, environmental, and social factors. Salvador, the biggest city in the region, played a central role in

the context of the epidemic and was a pioneer in reporting the ZIKV infection and registering a high number of cases

of CZS. The aim of the study was identifying the incidence and spatial distribution pattern of children with CZS in the

municipality of Salvador, according to living conditions.

Methods: This is an ecological study that uses the reported cases of ZIKV and CZS registered in the epidemiological

surveillance database of the Municipal Secretariat of Health of the city of Salvador between August of 2015 and July

of 2016. The neighborhoods formed the analysis units and the thematic maps were built based on the reported cases.

Associations between CZS and living conditions were assessed using the Kernel ratio and a spatial autoregressive

linear regression model.

Results: Seven hundred twenty-six live births were reported, of which 236 (32.5%) were confrmed for CZS. Despite

the reports of ZIKV infection being widely distributed, the cases of CZS were concentrated in poor areas of the city. A

positive spatial association was observed between living in places with poorer living conditions and births of children

with CZS.

Conclusions: This study shows the role of living conditions in the occurrence of births of children with CZS and indi￾cates the need for approaches that recognize the part played by social inequalities in determining CZS and in caring

for the children afected.

Keywords: Congenital Zika syndrome, Ecological study, Social determinants of health

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Background

Zika virus (ZIKV) infection and its efects on infant

development emerged around 5 years ago as a new and

serious public health problem in Brazil and the world [1,

2]. Epidemiological and clinical evidence have suggested

an association between ZIKV infection during pregnancy

and neurological alterations in newborns [3–5]. Tis

Open Access

†

Marcos Paulo Almeida Souza, Márcio Santos da Natividade, Guilherme

Loureiro Werneck and Darci Neves dos Santos contributed equally to this

work.

*Correspondence: [email protected]

2

Department of Surgery, University Hospital of Lagarto, Federal University

of Sergipe, Lagarto, Sergipe, Brazil

Full list of author information is available at the end of the article