There had been no cases of polio in the United States for almost a decade, and in upstate New York for more than 20 years. The contagious infectious disease was considered eradicated in the USA. In the summer, however, a young man north of the metropolis New York became infected with the virus, and his legs are now partially paralyzed. Since then, polio viruses have been repeatedly detected in the wastewater of several communities in the state and also in the metropolis.
“If you have a polio patient with paralysis, you know immediately that there is a bigger problem,” said polio expert Diedrich from the Robert Koch Institute (RKI) in Berlin recently. Because only in about one in 200 cases does an infection lead to the irreversible paralysis typical of polio – and that only in unvaccinated people. Such a case can therefore mean hundreds of infected people without symptoms in the region.
Risk for unvaccinated high
Governor Kathy Hochul declared a state of emergency. The risk is high for people not vaccinated against polio, said the governor and called on all residents to catch up on immunizations if necessary.
“If your child isn’t vaccinated or their vaccination status isn’t up to date, then the risk of a debilitating disease is real,” New York City Health Commissioner Mary Bassett said to all parents. According to the authorities, around 14 percent of children between the ages of six months and five years in the metropolis are not or not fully vaccinated against polio. Routine vaccinations such as polio have been suspended in many countries during the pandemic years.
The disease, which is often spread through contaminated hands as a so-called smear infection or through contaminated water, can cause paralysis and lead to death, and small children in particular can suffer permanent paralysis.
Before the introduction of vaccinations, there were thousands of sick people and hundreds of deaths every year in Germany alone. The worldwide vaccination campaigns initiated in 1988 have so far saved around 20 million people from paralysis and one and a half million from death, according to the World Health Organization (WHO). In the meantime, however, the vaccination rates are far too low in many places.
Not only USA affected
It’s not just the United States that’s affected. In Israel, the pathogen was first detected in a four-year-old child in Jerusalem at the beginning of March. Subsequently, more cases and polioviruses were found in the sewage of several cities in the country. In London, health authorities became aware in June when polioviruses were repeatedly found in sewage samples. According to the government, tens of thousands of children are at risk there alone.
The pathogens detected in the three countries are not the wild type of the polio virus, but viruses that go back to the oral vaccination with weakened but living polio pathogens. They can be excreted by vaccinated people for up to six weeks. Initially, infection via saliva and throat secretions is also possible. According to experts, other countries could also be affected.
Israel uses live oral vaccines (OPVs), but the US and UK do not. Inactivated vaccines (IPV) that do not contain any viable viruses have been in use there for a long time – as in Germany since 1998 exclusively. The pathogens circulating in London and New York were probably first introduced by people who had received the oral vaccination, which is still widespread in their country.
No cure for polio
The WHO has now put the USA on the list of countries – currently around 30 – in which vaccination-based polioviruses are spreading. “The United States is taking all appropriate action to prevent new cases of paralysis,” the CDC said. So far there is no cure for polio.
In Africa and Asia in particular, oral vaccination with live vaccines is still widely used. The very low risk of a vaccination polio case is accepted in favor of a large-scale immunization of the population.
In the USA, too, following the polio outbreak in New York, the reintroduction of the oral vaccination is now being considered. There is now a new live vaccine with a virus that does not multiply as well and cannot be excreted for as long. “Since the outbreak in New York, we’ve decided that we need to look at polio again,” Oliver Brooks, chair of a CDC working group on the issue, told CNBC. “We just have to do that.”
In Germany, babies are vaccinated from the age of two months, and according to RKI expert Diedrich, the vaccination rate is around 90 percent nationwide. “That’s not enough,” she emphasized. The rate is particularly low in Bavaria and Baden-Württemberg, for example. One problem in this country is that the collective memory has lost the terrible consequences polio had for countless children – and could have again. “This is by no means to be taken lightly.”
