Polio–not quite eradicated

Some experts say it’s possible a new polio epidemic could happen in the United States as more parents opt out of immunizing their children.

Iron lungs crowd a polio ward in Boston during 1955 epidemic (AP)

By the 1950s, polio had become one of the most serious communicable diseases among children in the United States. In 1952 alone, nearly 60,000 children were infected with the virus; thousands were paralyzed, and more than 3,000 died.¹

Poliomyelitis – commonly shortened to polio – is an infectious disease caused by the poliovirus.  It only occurs naturally in humans. In about 0.5% of cases, it affects the central nervous system with muscle weakness resulting in a flaccid paralysis. The weakness most often involves the legs, but may less commonly involve the muscles of the head, neck, and diaphragm.  In those with muscle weakness, about 2 to 5% of children and 15 to 30% of adults die.  Up to 70% of children infected are asymptomatic, about 25% have minor symptoms such as a fever and sore throat and up to 5% have headache, neck stiffness, and pains in the arms and legs.²

Through vaccinations, the numbers of paralytic cases in the U.S. dropped from more than 21,000 in 1952 to 2,525 reported in 1960 and only 61 in 1965. World-wide, the incidence of poliomyelitis declined significantly with widespread use of the poliovirus vaccine. Polio paralyzed an estimated 350,000 individuals per year in the 1980s in more than 125 countries. In 1994, the Western Hemisphere was certified to be free of indigenous wild poliovirus.  By 2019, only 125 cases caused by wild poliovirus were reported globally.  Unfortunately, a vaccine-derived poliovirus (VDPV) – a  strain of the weakened poliovirus that was initially included in oral polio vaccine – caused outbreaks in 20 countries in Africa and Asia, and paralyzed 369 children.³

1. Beaubien, Jason. “Wiping out Polio: How The U.S. Snuffed out a Killer.” NPR. October 15, 2012. Accessed August 13, 2021. https://www.npr.org/…. wiping-out-polio-how-the-u-s-snuffed-out-a-killer.
2. “Polio.” Wikipedia. last edit August 7, 2021. Accessed August 12, 2021. https://en.wikipedia.org/wiki/Polio.
3. Estivariz, Concepcion F, Ruth Link-Gelles, and Tom Shimabukuro. “Pinkbook: Poliomyelitis.” Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, updated last November 16, 2020. Accessed August 12, 2021. https://www.cdc.gov/vaccines/pubs/pinkbook/polio.html.