Risk Assessment and Control on Vaccine-Preventable Diseases

Poliomyelitis (polio) is a highly infectious intestinal disease caused by the poliovirus. Poliovirus is transmitted by person-to-person spread mainly through the fecal–oral route, or, less frequently, by contaminated water or food. Humans are the only known reservoir of poliovirus, which is transmitted most frequently by persons with inapparent infections. Initial symptoms of polio include fever, fatigue, headache, vomiting, stiffness in the neck, and pain in the limbs. In a small proportion of cases (1 in 200 infections), poliovirus causes paralysis, which is often permanent. Instead of a cure for polio, it can only be prevented. The Polio vaccine, given multiple times, can protect a child for life.