Poliomyelitis is an ancient disease that has resulted in significant morbidity and mortality worldwide for centuries. Its history is complicated by changes in the way humans adapt and live, and advancements in prevention and treatment were fueled by human emotion and personal experience that have been rarely rivaled throughout history. The progression of the fight against polio has shown us the life-saving power of vaccines, the unexpected impact of improved hygiene and quality of life on disease transmission and the impact of global collaboration and discovery.
What is polio? Poliovirus is a member of the genus Enterovirus within the family Picornaviridae. Poliomyelitis is a highly infectious disease caused by poliovirus that tends to impact children most significantly. The disease is spread from person to person via the fecal-oral route or when someone comes in contact with food or water containing infected fecal material.
Once inside the body, the virus replicates in the oropharyngeal and intestinal mucosa . From this point, the virus moves into the cervical and mesenteric lymph nodes (lymph nodes in the membrane that connects the bowel to the abdominal wall), followed by the blood, causing viremia that results in a flu-like illness. This will be the result for most people infected with poliovirus, particularly if they have some existing level of immunity.
However, the virus sometimes invades the nervous system and causes paralysis. One in 200 infections lead to irreversib.