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bioRxiv · 10.1101/039610

Model-based projections of Zika virus infections in childbearing women in the Americas

Alex Perkins·Amir Siraj·Corrine Warren Ruktanonchai·Moritz Kraemer·Andrew Tatem
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Abstract

Zika virus is a mosquito-borne pathogen that is rapidly spreading across the Americas1. Due to a probable association between Zika virus infection and a congenital neurological disorder called microcephaly2, the epidemic trajectory of this viral infection poses a significant concern for the nearly 15 million children born in the Americas each year. The potential magnitude of the ongoing Zika epidemic is exceedingly difficult to gauge based on existing data3, due to a number of uncertainties that cloud the relationship between observed cases and true infections. As an alternative to methods that depend on unreliable case data, we developed and applied a new method that leverages highly spatially resolved data about drivers of Zika transmission to project that 1.1 (1.0-1.9) million infections in childbearing women and 64.2 (53.6-108.1) million infections across all demographic strata could occur before the first wave of the epidemic concludes. Our projection is largely consistent with annual, region-wide estimates of 53.8 (40.0-71.8) million infections by dengue virus4, which has many similarities to Zika. Our projection is also consistent with state-level data from Brazil on confirmed, Zika-associated microcephaly cases5, and it suggests that the current epidemic has the potential to negatively impact tens of thousands of pregnancies. These projections constitute an important early contribution to efforts to understand the potential magnitude of the Zika epidemic, and our methods offer a new way to make rapid assessments of the threat posed by emerging infectious diseases.

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Alex Perkins, Amir Siraj, Corrine Warren Ruktanonchai, Moritz Kraemer, Andrew Tatem. 2016-02-12. Model-based projections of Zika virus infections in childbearing women in the Americas. https://doi.org/10.1101/039610

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