Investigation of airport sewage to detect importation of poliovirus, Poland, 2017 to 2020

Abstract

Background Polioviruses are human pathogens which may easily be imported via travellers from endemic areas and countries where oral polio vaccine (OPV) is still routinely used to polio-free countries. Risk of reintroduction strictly depends on polio immunisation coverage. Sustaining a polio-free status requires strategies that allow rapid detection and control of potential poliovirus reintroductions. Aim The aim of this study was to apply environmental surveillance at an international airport in Poland to estimate the probability of poliovirus importation via air transport. Methods Between 2017 and 2020, we collected 142 sewage samples at Warsaw Airport. After sewage concentration, virus was isolated in susceptible cell cultures. Poliovirus isolates were characterised by intratypic differentiation and sequencing. Results Seven samples were positive for polioviruses. All isolates were characterised as Sabin-like polioviruses type 3 (SL-3). No wild or vaccine-derived polioviruses were found. The number of mutations accumulated in most isolates suggested a limited circulation in humans. Only one SL-3 isolate contained seven mutations, which is compatible with more than half a year of circulation. Conclusion Since OPV was withdrawn from the immunisation schedule in Poland in 2016, detection of SL-3 in airport sewage may indicate the events of importation from a region where OPV is still in use. Our study shows that environmental surveillance, including airport sewage investigation, has the capacity to detect emerging polioviruses and monitor potential exposure to poliovirus importation. Poliovirus detection in sewage samples indicates the need for sustaining a high level of polio immunisation coverage in the population.

Optimization and performance analytics of global aircraft-based wastewater surveillance networks

“…Traditionally, wastewater surveillance has been used to monitor community prevalence of pathogens such as SARS-CoV-2 variants [6,7], polio [8,9], and influenza [10,11]. Expanding wastewater surveillance at airports to create a global wastewater surveillance network (WWSN) has been recently proposed as a novel, early warning system against emerging pathogens [12][13][14][15][16][17]. Sampling aircraft wastewater provides a noninvasive method to monitor the spread of pathogens, but the creation of a global…”