Nurse Lydia Fulton prepares the measles, mumps and rubella vaccine, as well as the vaccine used to prevent diphtheria, pertussis, tetanus and polio, at Children’s Primary Care Clinic in Minneapolis.
Courtney Perry | The Washington Post | Getty Images
Childhood polio vaccination rates are as low as 37% in some communities in the New York City metro area despite vaccine mandates, raising the risk of an epidemic as the virus spreads locally for the first time in decades.
Polio vaccination is mandatory for all children attending daycare and K-12 schools in New York, regardless of state, private or religious affiliation.
There are no exemptions from New York State’s vaccine mandate for religion or personal belief. Examples are given only if the child actually has a medical condition that would prevent the child from receiving the vaccine.
Despite this mandate, childhood polio vaccination rates have declined in some communities. According to the Centers for Disease Control and Prevention, in suburban Rockland County, New York, vaccination rates for children under 2 years old fell from 67% in 2020 to about 60% in 2022. In some districts of the county, only 37% of children of this age are vaccinated against poliomyelitis.
Children should receive four doses: one at 2 months, a second at 4 months, a third between 6 and 18 months and a fourth between 4 and 6 years of age, according to the CDC.
According to the New York State Department of Health, the overall polio vaccination rate for 2-year-olds is 79%. According to a CDC survey published in October 2021, nearly 93% of US children under the age of 2 have been vaccinated against polio.
But this summer, an outbreak of polio among young adults in Rockland County has alarmed public health officials. Sewage samples collected in Rockland County, Orange County and New York City since May have tested positive for polio, indicating the virus has been circulating in the metropolitan area for months.
The case of an adult in Rockland County is the second case of the virus causing local transmission of polio in the United States since 1979, according to the CDC. New York State Health Commissioner Dr. Mary Bassett called the sewage findings alarming, and the CDC warned that the virus poses a continuing threat to unvaccinated people.
According to the CDC, every case of polio represents a public health emergency.
“It’s a wake-up call that we need to address this problem with our vaccination rates because I’ve never seen a child with iron lung and I don’t want to,” said Dr. Adam Ratner, director of pediatric infectious diseases at NYU Langone Health.
According to Ratner, New York State previously had a religious exemption from school vaccine mandates, which led to a decline in vaccinations. This exemption was lifted in 2019 after a drop in vaccinations led to an outbreak of measles. But the onset of the Covid pandemic in 2020 led to school closures and health care worker disruptions, leading to a decline in polio vaccine administration, according to the CDC.
“Once people started going to the doctor because a lot of the schools were so far away, the vaccine mandates weren’t being met in places. So you still have a group of kids who aren’t immunized,” Ratner said.
Ratner said there was only one way to prevent further cases of polio: “Getting vaccinated is the solution.”
The Rockland County Health Department launched a campaign in late July to help close the vaccination gap, but the CDC says not enough doses have been given to significantly increase vaccination coverage in the county.
Two doses of the polio vaccine are at least 90% effective in preventing paralysis from the virus, and three doses are 99% to 100% effective, according to the CDC.
What is poliomyelitis?
Poliovirus, which can cause the disease known as poliomyelitis or poliomyelitis, is a devastating, highly contagious virus that struck a chord with parents before vaccines became available in the 1950s. In the United States in the late 1940s, on average, more than 35,000 people were disabled by polio each year. There is no cure for poliomyelitis.
The virus enters a person’s spinal cord and causes permanent paralysis of the arms and legs. In some cases, poliomyelitis is fatal because it paralyzes the muscles needed for breathing and swallowing. Most people infected with the virus do not show symptoms, but they can spread the virus to others and make them sick.
The virus, which lives in the intestines and food, is spread through what doctors call the fecal-oral route. Young children are at particular risk of putting their hands, toys, or other fecal-contaminated objects in their mouths. According to the CDC, the virus can also be spread through respiratory droplets when a person sneezes or coughs, but this is less common.
A successful vaccination campaign reduced polio cases from more than 15,000 cases per year in the early 1950s to 10 in the 1970s. Since 1979, not a single case of polio has been reported in the United States
“We’ve gotten to this point in the U.S. with tremendous effort. It’s sad to see us backtrack,” Ratner said.
According to the World Health Organization, two of the three natural strains of poliovirus have been eradicated worldwide. But travelers have occasionally brought the virus into the United States, and the strain now spreading in the New York area almost certainly came from overseas.
The strains in the Rockland County adults were linked to a weakened form of the virus used in the oral polio vaccine. The US stopped using this vaccine more than 20 years ago, so someone vaccinated outside the country introduced the virus into the US.
The oral vaccine uses a weakened virus that can still reproduce in the human body, and in rare cases the strain can revert to the type that attacks the nervous system. When this happens, a person who has recently been vaccinated with the oral vaccine can infect an unvaccinated person, which can cause paralysis.
“This is one of the reasons why we don’t use the oral polio vaccine because there is always a risk of transmission, especially to people who are immunocompromised or unvaccinated,” said Dr. Waleed Javid, an epidemiologist at Mount Sinai Hospital in New York. The oral vaccine is used in some countries because it is effective, inexpensive, easy to administer, and usually safe.
The US uses the polio vaccine as a series of vaccines in which the strain of the virus is inactivated so it cannot multiply, spread or cause disease.
According to the CDC, the polio vaccine protects people for years after the primary vaccination series, but the exact duration of protection is unknown. Adults who were vaccinated as children but are at high risk for polio can receive one booster. Javid said people with concerns, such as those with compromised immune systems, should consult with their primary care physician to determine their risk category and receive a different dose of the vaccine.
But there is no reason for the general public to panic, Javid said. Most people are vaccinated and protected against polio. And for those who don’t, the solution is simple—vaccination.