Social determinants of health associated with topical repellent use in pregnancy: a cross-sectional study during a Zika outbreak in Brazil

Background: Repellent use during pregnancy was strongly recommended after uncovering Zika virus (ZIKV) involvement with congenital malformations. In this context, Pernambuco, Brazil played a key role since it was the epicentre for the main studies suggesting ZIKV teratogenicity and one of Brazil's most affected states during the 2014-2016 epidemics. Thus we aimed to identify possible associations between social determinants of health and repellent use in pregnancy during the ZIKV outbreak in Pernambuco. Methods: We conducted a cross-sectional study (July-December 2016) with 539 pregnant women residing in Pernambuco and estimated the associations by prevalence ratio and multivariable logistic regression. Results: Repellents were associated with pregnant women ≥30 y; graduates, employed, health professionals, private health system users and with a monthly income per person greater than two minimum wages. Women whose domiciles favour mosquitoes (ground-floor houses, intermittent water supply from general distribution or water trucks and for ≤6 d/week, cesspools/open wastewater, indoor household water storage) were less likely to use repellents. There was no association for peridomiciles. Conclusions: Repellents were not associated with ZIKV in most vulnerable pregnant women, despite all the general recommendations made during the Pernambuco epidemic. This study observed a demand for public policies focused on health, education and sanitation problems related to deprived social groups along with their co-responsibility rather than focusing on individual attitudes against mosquitoes.