UK health officials are urging parents to get their children vaccinated on time after a sample taken from a London sewer was found to contain the polio virus. The health department has asked the officials to be alert after the virus was found.

The UK Health Protection Agency (UKHSA) said further investigations were underway for poliovirus detected in samples taken in February and May.

According to experts, the polio virus found in the sample has been identified as Vaccine Derived Poliovirus Type 2 (VDPV-2). The virus can cause serious illness, such as paralysis in unusual cases. People who have not been fully vaccinated are more likely to get this type of disease.

The polio virus has been a major concern in the UK since 1984. Britain was declared polio free in 2003. Areas where vaccination is low. The virus is likely to spread rapidly in such areas.