Causative agent
It is caused by poliovirus.

Clinical features
The disease mainly affects young children. It can cause fever, headache, vomiting, abdominal discomfort, muscle pain, stiffness in the neck and back, and paralysis. Most patients will recover, but in severe cases, it can lead to permanent disability and death.

Mode of transmission
The disease is highly infectious. It is spread from person-to-person, mainly through the faecal-oral route. The virus enters the body through oral route and finally invades the central nervous system.

Incubation period
It is usually 7 to 14 days, with a range from 3 to 35 days.

Management
Suspected infected persons should be referred to the hospital for further management and isolation. Currently, there is no curative treatment for the disease.

Prevention
Vaccination is the most effective way of preventing the disease. There are two types of polio vaccine: Oral Polio Vaccine (OPV) to be taken by mouth and Inactivated Polio Vaccine (IPV) to be given by injection. Children in Hong Kong should follow the recommended schedule in the Hong Kong Childhood Immunization Programme (HKCIP) for vaccination. Inactivated poliomyelitis vaccine has been used in HKCIP since 2007. Parents should consult family doctors for details.