I am glad that you heard about this recent case of polio in New York City. This young man did not receive polio vaccine, and developed paralysis in his legs after a short illness. Tests of his stool showed that he was infected with poliovirus. This incidence highlights the importance of polio vaccine in preventing poliovirus infection here and around the world.

Polio was a terrifying disease in the last century. Many children and adults around the world were paralyzed and died after contracting poliovirus. When paralysis involved the diaphragm, the muscle between the chest and abdomen that helps us to breathe, they were put inside a chamber called “iron lungs” that helped them to breathe and kept them alive. Although they didn’t die, they had to stay in the chambers for the rest of their lives.

Images of those paralyzed in their legs and walking with crutches, as well as those kept alive in “iron lungs” motivated parents to immunize their children with polio vaccines when they were invented in 1950s and 1960s. Within a few decades, polio was wiped out of most countries around the world.

Unfortunately, poliovirus is not eradicated everywhere. There are still places where the virus is circulating; children are still being paralyzed and dying because polio vaccine couldn’t reach them due to various geopolitical reasons. With the ease of worldwide travel, it is easy for poliovirus to spread again in North America where many parents have let their guards down.

Because polio vaccines are so effective, many parents have not heard about this devastating disease. Some question the need for childhood vaccination because they haven’t heard about diseases like polio or meningitis that were rampant in their parents’ or grandparents’ generation. In some regions of Canada and United States, the percentage of children receiving their childhood vaccination has dropped to dangerously low levels. We have already seen outbreaks of whooping cough because children didn’t get their vaccine.

When New York City investigated this young man paralyzed by polio, they found the presence of poliovirus in the sewage system in those counties where the vaccination rates were low. This indicates that there is spread of poliovirus in the community, although others didn’t develop paralysis. We cannot predict who will get paralyzed after poliovirus infection; those who have weakened immune system are more likely to develop paralysis.

With this report of polio in New York, scientists in Canada are concerned as well. Our childhood immunization rate has dropped in recent years, polio can once again happen in Canada. As a result, there is a plan to test for poliovirus (in addition to Covid-19 virus) in our sewage system. This can be used as an early warning system to detect poliovirus infection in Canada.

Since you didn’t receive polio vaccine as a child, you are likely unprotected against poliovirus. If you come across this virus, almost certainly you will get infected. It is impossible to know how sick you may get. We know that polio vaccine is safe and effective, you should get vaccinated even as an adult. Public health offices around the country have protocols to immunize adults with polio and other vaccines.

Furthermore, your children should receive their childhood vaccines, which include polio vaccine. These vaccines will protect them against serious infections and keep them healthy. Please don’t delay that any longer.