A: Polio was never gone, but there is a re-emergence in places where it has not been found for many decades.
Polio is an infectious disease that many Americans over 70 might remember from their childhoods. Mass vaccination campaigns in the U.S. and many other countries largely stopped the virus from circulating for many decades, although children do continue to be vaccinated. Less than 1% of cases will result in paralysis. Wild polio virus still spreads in some parts of the world, including, for example, in Pakistan and Afghanistan.
In August 2022, a man was diagnosed with polio and hospitalized in New York. There have been recent cases in London, Jerusalem, and in the greater New York area. The man who was hospitalized in New York was unvaccinated. In some countries, a live polio vaccine is given that has a tiny chance of causing some people to develop the infection due to fecal shedding. This vaccine is not used in the U.S. and poses minimal threat to anyone who is vaccinated, but if an unvaccinated person travels to a country where that version of the vaccine is used, there is a chance that person will catch polio. This is what probably happened in the case in New York.
Although the polio virus was detected in New York City sewer systems, the virus does not pose much of a threat to people who have been vaccinated against it. There are increasing pockets of people who have not been vaccinated, and this is probably responsible for the current re-emergence. People who are not vaccinated may travel to other parts of the world where the virus is still active and return with the illness. The fall in vaccination rates may in some cases be related to a general fall in routine vaccinations during the COVID pandemic, although low vaccination rates may already have been a problem in certain communities.
If you are concerned about the polio virus, the most important thing to do is to determine whether or not you are already vaccinated. This would most likely have occurred when you were a child, and your pediatrician should have a record. You can also try to request old vaccination rates if your state has an Immunization Information System (IIS) in place. In New York City, these records can be accessed online. Adults and children who are not vaccinated should consult with their doctors to get vaccinated as soon as possible.
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