Staying one step ahead of polio: WHO builds awareness of advanced sequencing technology

WHO/Europe has joined forces with Imperial College and the Medicines and Healthcare products Regulatory Agency (MHRA) in the United Kingdom to organize a series of training workshops on the use of direct detection and nanopore sequencing (DDNS) to detect and characterize polioviruses - the type of virus that causes poliomyelitis (polio). Funded by the Bill and Melinda Gates Foundation, this activity is expected to build awareness of this advanced technology and its use in strengthening poliovirus surveillance in the WHO European Region.

The latest workshop in the series took place on 17-21 June 2024, hosted by the WHO Polio Global Specialized Laboratory at the MHRA. It included both theoretical and practical training sessions on the use of DDNS for polioviruses, and was attended by virology specialists from Finland, France, Italy, Netherlands (Kingdom of the), Spain and Ukraine.

Early detection saves lives

Polioviruses are stealthy - by the time the first signs of life-threatening polio appear in a country, many hundreds of children and/or adults are typically already infected and can unknowingly pass on the dangerous virus to others who may not be fully vaccinated and protected.

The Region was declared polio-free in 2002, but importations of the virus into the Region will continue to occur until global eradication is achieved. Suboptimal vaccination coverage in some areas or population groups in the Region create persistent pockets of vulnerability to the disease. Detecting the virus's reappearance quickly and reliably is critical to allow for the rapid initiation of measures to stop the spread and minimize its potential impact.

The DDNS approach is currently under validation by the WHO Global Polio Laboratory Network (GPLN) but can already be used today reliably for poliovirus sequencing. It can also be of interest to countries that conduct non-polio enteroviruses surveillance, as the clinical significance of these viruses is increasing.

Region-wide laboratory network

The WHO European Polio Laboratory Network, coordinated by WHO/Europe, is part of the GPLN and consists of 47 laboratories in 37 countries that provide poliovirus diagnostic services to all 53 Member States in the Region. This network conducts testing of samples suspected of containing polioviruses in the Region and sequencing of polioviruses to identify origins and chains of transmission. These laboratories play a critical role in enabling the Region to sustain its polio-free status.