Zika virus infection and microcephaly: spatial analysis and socio-environmental determinants in a region of high Aedes aegypti infestation in the Central-West Region of Brazil

Abstract

Background More than 5 years after the Zika virus (ZIKV) epidemic, Zika infection remains a major concern in regions with high Aedes infestation. The objectives of this study were (i) to identify clusters of ZIKV infection and microcephaly, and/or central nervous system (CNS) alterations associated with congenital infection during the epidemic peak in 2016 and subsequently, in 2017 and 2018; (ii) to measure the non-spatial correlation between ZIKV infection and microcephaly and/or CNS alterations associated with congenital infection; and (iii) to analyse the sociodemographic/economic, health, and environmental determinants associated with the incidence of ZIKV in a region of high infestation by Aedes aegypti in the Central-West Region of Brazil. Methods This ecological study analysed 246 municipalities in the state of Goiás (6.9 million inhabitants). The data were obtained from the Information System for Notifiable Diseases (ZIKV cases) and the Public Health Event Registry (microcephaly and/or CNS alterations associated with congenital infection). Incidence rates and prevalence of ZIKA infection were smoothed by an empirical Bayesian estimator (LEbayes), producing the local empirical Bayesian rate (LEBR). In the spatial analysis, ZIKV infection and microcephaly cases were georeferenced by the municipality of residence for 2016 and grouped for 2017 and 2018. Global Moran's I and the Hot Spot Analysis tool (Getis-Ord Gi* statistics) were used to analyse the spatial autocorrelation and clusters of ZIKV infection and microcephaly, respectively. A generalised linear model from the Poisson family was used to assess the association between ecological determinants and the smoothing incidence rate of ZIKV infection. Results A total of 9892 cases of acute ZIKV infection and 121 cases of microcephaly were confirmed. The mean LEBR of the ZIKV infection in the 246 municipalities was 22.3 cases/100,000 inhabitants in 2016, and 10.3 cases/100,000 inhabitants in 2017 and 2018. The LEBR of the prevalence rate of microcephaly and/or CNS alterations associated with congenital infection was 7 cases/10,000 live births in 2016 and 2 cases/10,000 live births during 2017–2018. Hotspots of ZIKV infection and microcephaly cases were identified in the capital and neighbouring municipalities in 2016, with new clusters in the following years. In a multiple regression Poisson analysis, ZIKV infection was associated with higher population density, the incidence of dengue, Aedes larvae infestation index, and average rainfall. The important determinant of ZIKV infection incidence reduction was the increase in households attended by endemic disease control agents. Conclusions Our analyses were able to capture, in a more granular way, aspects that make it possible to inform public managers of the sentinel areas identified in the post-epidemic hotspots.

Risk of adverse pregnancy and infant outcomes associated with prenatal Zika virus infection: a post-epidemic cohort in Central-West Brazil

“…Whereas 67% of the ZIKV-positive women were detected in 2017, 89% of the ZIKV-negative group were recruited in 2018. Consistent with previous findings from an ecological study using surveillance data from Goiânia 18 , our findings underscore the persistence of the ZIKV circulation beyond the peak in 2015–2016 but also highlight the rapid decline of ZIKV transmission in subsequent years. These observations are also consistent with national surveillance data 19 , 20 as well as the broader epidemiological trends in ZIKV circulation across the American region 21 .…”

“…In this hotspot, the risk of microcephaly was 56.7 per 10,000 newborns during 2015–2016, the peak of the epidemic, compared with the historical risk of microcephaly of 2.0 per 10,000 newborns 17 . The Central-West region, where this study was conducted, was less affected with an estimated risk of microcephaly of 14.5 per 10,000 newborns during 2015–2016, with a sharp decline in subsequent years 17 , 18 . Using data from a prospective cohort of pregnant women who presented with rash (i.e., a common symptom of ZIKV infection) between January 2017 and April 2019 in the Goiânia metropolitan area in Central-West Brazil, this study aimed (i) to estimate the risks of adverse pregnancy and infant outcomes (i.e., in the first year of life) related to prenatal ZIKV exposure and (ii) to investigate whether specific symptoms could distinguish between ZIKV-positive and ZIKV-negative pregnant women with rash during a period of low ZIKV circulation.…”

Molecular functions of ANKLE2 and its implications in human disease

“…CZS is characterized by a range of significant birth defects, including congenital contractures, ocular abnormalities ( Campo et al, 2017 ), hip displacement ( da Fonseca et al, 2023 ) and, in the most severe cases, MCPH ( de Araújo et al, 2016 ; Mlakar et al, 2016 ; Moore et al, 2017 ). The occurrence of microcephaly after congenital ZIKV exposure is ∼5% and varies dramatically with gestational timing ( Roth, 2022 ) as well as many other environment- and virus-associated factors ( Adachi et al, 2020 ; Nunes et al, 2021 ). CZS-associated microcephaly has a mortality rate of ∼10%, but this also varies with severity of disease and other factors (N. Costa et al, 2020 ).…”