New York health officials are stepping up efforts to increase polio vaccination rates in local children as even more polio virus has turned up in sewer samples.
On Friday, Aug. 12, New York State and New York City health officials announced that polio virus had been detected for the first time in New York City’s sewers, indicating local circulation of the virus.
The finding follows similar detections in sewer sampling in nearby Rockland and Orange counties in May, June and July. On July 21, Rockland County health officials reported a case of paralytic polio in a young, unvaccinated male resident who had not recently traveled out of the country. The man’s symptoms began in June.
The Centers for Disease Control and Prevention estimate that only about one in 200 people infected with poliovirus develop paralysis. For example, the identification of the paralyzed case last month indicates that hundreds of others could also be infected. And, over time since the start of the case, the cumulative total of cases could run into the thousands.
“For every identified case of paralytic polio, hundreds may go undetected,” New York state health commissioner Mary Bassett said in a statement. “The detection of poliovirus in wastewater samples in New York City is alarming, but not surprising.” New York City, state and CDC officials are responding “urgently” and “aggressively assessing the spread,” she added.
The circulating polio virus is only a threat to those who have not been vaccinated. Fortunately, most Americans are vaccinated and are therefore not at risk. The four-dose inactivated poliovirus vaccine is part of routine vaccination schedules in the US, and most children receive the first three doses within 18 months. The fourth dose is given between the ages of 4 and 6 years. Not all children are vaccinated, however, and there are some communities with low vaccination rates, including some in New York City and neighboring suburbs.
Risk and luck
In New York, 78.96 percent of children statewide received the first three doses by age 2. But in Rockland County, the vaccination rate for children under age 2 is only 60 percent. And in Orange County, it’s just under 59 percent in children under age 2. Vaccination coverage in New York City is higher, but officials say it has been declining since 2019. Currently, only 86 percent of NYC children under the age of 5 are fully vaccinated, meaning 14 percent are vulnerable to the dangerous disease.
“The risk to New Yorkers is real, but the defense is so simple: Get vaccinated against polio,” said New York Health Commissioner Dr. Ashwin Vasan, in a statement. “Now that polio is circulating in our communities, there is simply nothing more essential than vaccinating our children to protect them from this virus, and if you are an unvaccinated or incompletely vaccinated adult, choose now to get the vaccine. Polio is completely preventable and it’s return should be a call to action for all of us.”
New York officials aren’t the only ones struggling to deal with a resurgence of the polio virus. UK officials announced this week that they had detected 116 polio virus isolates from 19 sewer samples in at least eight boroughs of London since February. Officials are now working to vaccinate all children aged 1-9 across London.
“In London, it’s just luck that no one has been paralyzed by these viruses that have been picked up,” David Salisbury, WHO Global Commission for Certification of Polio Eradication, said in a statement. “Those who have been vaccinated are well protected — it is those people who have not been vaccinated or have been insufficiently vaccinated who are at risk.”
In London and New York, officials have detected genetically linked isolates of the vaccine-derived poliovirus (specifically, vaccine-derived poliovirus type 2 or VDPV2), which arises from oral polio vaccines. These vaccines, which are no longer used in the UK and US, contain attenuated, replicating viruses and are safe, effective and affordable. But if given in areas with poor hygiene, poor sanitation and low vaccination rates, the vaccine virus can spread, mutate and regain the ability to cause disease and paralysis.
