Insights from a Systematic Search for Information on Designs, Costs, and Effectiveness of Poliovirus Environmental Surveillance Systems
by Radboud J. Duintjer Tebbens, Marita Zimmermann, Mark A. Pallansch, and Kimberly M. Thompson, Food and Environmental Virology 2017; doi: 10.1007/s12560-017-9314-4 (published on-line July 7, 2017).

Answers to frequently asked questions

What are the study’s main findings?
What are the study’s main recommendations?
Background on polio

What are the study’s main findings?

• Motivated by the ongoing global expansion of poliovirus environmental surveillance (ES), this systematic review identified 101 distinct poliovirus ES activities conducted in 48 countries between 1975 and 2016 that varied widely in objectives, sample collection sites and methods, and laboratory processing methods. More recent ES activities conducted in the context of global polio eradication efforts showed relatively greater consistency in methods in accordance with World Health Organization ES guidelines.
• Very few studies provided any estimates of the costs of conducting ES and no studies provided complete cost information.
• Although we found information from some studies about catchments area population sizes, collected sample volumes, and fractions of the volume tested for polioviruses, the studies did not consistently report all of the information needed to determine the sensitivity of ES.
• Studies that deliberately introduced poliovirus in sewage systems, studies that compared ES findings to isolation rates from stools (in the context of known exposure to polioviruses in the population), and studies that detected limited transmission in the absence of clinical polio detections in the same population confirm the potentially very high sensitivity of ES for large catchment areas connected by converging sewage networks.
• The overall population-level sensitivity of ES globally probably remains low because most people do not reside in catchment areas monitored by ES.
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• Determining the value of ES requires additional research to characterize the costs and effectiveness of ES.
• Systematic reporting by investigators of catchment area population sizes, collected sample volumes, and the fraction of concentrated samples tested for poliovirus would improve the assessment of the sensitivity of ES activities.
• Acute flaccid paralysis (AFP) surveillance remains the only poliovirus surveillance system with comprehensive global coverage. While ES can play an increasing role in detecting poliovirus transmission in high risk areas, continued investments in AFP surveillance remain critical for a successful polio endgame.
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