Nearly 75 percent of those infected with polio do not show any symptoms, says Health Ministry’s Disease Control Division public health specialist Dr Rohani Jahis.
According to Rohani, only one in four people infected with polio experience flu-like symptoms such as fever, fatigue, nausea, vomiting and headaches.
"Only 0.5 percent of the people infected with the virus suffer from paralysis. This means that not everyone becomes paralysed. But when we are infected with the virus, it will be secreted through faeces," she said when appearing as a guest on the ‘Ruang Bicara’ programme aired on Bernama TV yesterday.
The Health Ministry in a statement said a three-month-old baby was infected with vaccine-derived poliovirus type 1 (VDPV1) while being treated at a hospital's intensive care unit on Dec 6.
The polio case was the first in Malaysia since the country was declared free of the disease 27 years ago.
Rohani said polio has not yet been completely eradicated around the globe. At present, the virus is still endemic in three countries, namely Nigeria, Afghanistan and Pakistan.
"So the possibility of the virus coming from another country is there if children or people in the country are not vaccinated. So there is a risk of getting the infection," she said.
Rohani said if a person is infected with polio, there is no specific treatment to kill the virus, with healthcare only being supportive in nature such as by treating the flu and providing physiotherapy in the event of foot paralysis.
She stressed that the best course of action possible was to ensure that children and the public, in general, were immunised.
"In a community where most people have been vaccinated, when a poliovirus enters into the community, the virus cannot survive in the community, because everyone has been immunised.
"The issue is when there is absolutely none or low level of immunisation in the population, so the virus can survive and spread in the community, causing problems," she said.
According to the Malaysian National Immunisation Schedule, infants should receive the polio vaccine (IPV) at two months, three months and five months. Infants should also be given an additional dose when they are 18 months old.