The British health and Safety Authority said in a statement on the 22nd that poliovirus had been detected in sewage in North and East London and was currently classified as "vaccine derived" type 2 poliovirus. In rare cases, for those who have not been fully vaccinated, the virus can lead to serious diseases such as paralysis. The British health and Safety Authority said on the same day that the agency, in cooperation with the British drug and health products administration, found some poliovirus in the sewage samples collected from London Beckton sewage treatment plant from February to May. At present, it is classified as "vaccine derived" type 2 poliovirus. The British health and Safety Authority said the relevant findings showed that the virus may have spread among some closely related people in North and East London, and the virus exists in their excreta. The agency is investigating whether there is community transmission. However, the health and Safety Bureau stressed that no relevant cases of paralysis had been reported. Dr. Vanessa Saliba, an epidemiological consultant of the agency, said in a statement that vaccine derived poliovirus is rare and the overall risk to the public is extremely low; However, vaccine derived poliovirus has the potential to spread, especially in communities with low vaccination rates. In rare cases, it may paralyze people who have not been fully vaccinated. In 2003, Britain declared that the country had been polio free. According to the British health and safety authority, it is normal to find a small amount of "vaccine like" poliovirus in sewage samples every year during routine monitoring, but it was found once before and was not detected again. These traces of the virus came from the excreta of those who had received OPV overseas after returning or arriving in the UK. It is reported that some oral polio vaccines are inactivated vaccines, that is, the virus in the vaccine has not completely lost its activity. Polio, commonly known as polio, is an acute infectious disease caused by poliovirus, which mainly affects children under the age of 5. At present, there is no cure for poliomyelitis, and vaccination is still the most economical and effective way to prevent and control related diseases. (Xinhua News Agency)