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A living systematic review can help us to refine our understanding of the epidemiology of Zika virus. In this Q&A, Michel Counotte and Nicola Low, University Bern, Switzerland, talk about their living systematic review, the first of its kind to publish on F1000Research, and explain how it can help researchers handle the immense literature on the virus.

Why conduct this living systematic review and what do you hope it will achieve?

The volume of research on Zika virus that has accumulated over a short time period is enormous. This means that any systematic review in the field quickly becomes outdated. We want our living systematic review to be an up-to-date high-quality summary of research about Zika virus and its complications. Through our Zika Open Access Project (ZOAP), we want researchers and the public to know what research about Zika virus is being done.

What did you find? Do your findings agree with the earlier evidence that ‘Zika virus is a cause of congenital abnormalities and is a trigger of Guillain-Barré syndrome?

Our living systematic review reinforces the conclusions about the complications of Zika virus infection from our first update, where we explained how we moved from a classical to a living systematic review. The findings in this update are consistent, although there is a lot of heterogeneity between studies.

How has your review improved our understanding of the virus and are there any knowledge gaps that need to be filled?

With every update, new evidence refines our understanding of the epidemiology of Zika virus infection and its complications. In this update, we have been able to quantify the strength of associations between Zika virus infection in pregnancy and congenital abnormalities, including microcephaly (a condition where the head is smaller than normal due to damage of the developing brain tissue) and between Zika virus infection and Guillain-Barré syndrome (a condition that affects the nerves causing muscle weakness). But we still need to understand why the findings are so heterogeneous. We’ve also found gaps, for example, by identifying places in which a Zika virus outbreak did take place, but where there is no evidence of adverse outcomes. Is this an absence of evidence about clinical outcomes, or evidence of an absence of Zika virus complications?

What are the strengths of this article type? How many articles are added every month and why is it important to keep updating this review with new evidence?

With a living systematic review, we can include important research as soon as it is published. There are still about 200 new research publications about Zika every month, and our focused search strategy for studies about causality means that we screen 50-60 of these per month. Having regular updates increases our certainty about the whole body of evidence.

How can this benefit the research community and the public?

Researchers and the public can follow our project via Twitter @ISPM_ZOAP, since our automated workflow provides daily updates of new publications about Zika virus for everyone. Living systematic reviews also reduce the workload for many researchers, as we often start by finding an ‘old’ systematic review and then search the literature ourselves to update it, so that we have a resource that is always up to date.

What are the plans for future research?

We will keep incorporating evidence as it is published. We also continue to improve our workflow and explore new dynamic methods of visualizing information that changes over time, like the shiny map that we piloted in the last version of our review.