Poliovirus discovered in sewage samples from London

The first evidence that the virus may be returning to the country since the 1980s has been found in sewage samples from the British capital, but no cases have been reported, according to officials.

According to the UK Health Security Agency (UKHSA), the disease’s risk of infection was also minimal due to high immunization rates, which cause paralysis in children in less than 1% of cases.

After the virus was discovered during routine wastewater surveillance, the government nevertheless urged parents to make sure their kids were immunized, especially those who might have missed shots during the Covid-19 outbreak.

Nationwide vaccination rates are higher than the 90 percent threshold needed to stop outbreaks, but in recent years, London’s coverage rates for children under two have fallen below that benchmark.

Parents of children under five who are not immunized will start receiving calls from the city’s National Health Service.

Every year, thousands of children around the world are killed or paralyzed by polio, which is primarily spread through feces. Although there is no treatment, immunization has almost completely eradicated the disease’s wild, or naturally occurring, form.

UKHSA reported that while it typically discovers one to three samples of poliovirus in sewage each year, there have only ever been isolated cases in the past.

The Beckton Treatment Works in east London, which serves over 4 million people, identified one sample this year in February, and continuing detection has been occurring there since April.

In the past, the detections, according to UKHSA, happened when someone who had received the live oral polio vaccine overseas returned or visited the country and momentarily shed the virus in their feces.

They believe that this is also what occurred this time, with the important exception that the virus is likely to have spread among individuals who were previously in close contact with one another and mutated into a pathogenic form known as “vaccine-derived poliovirus.”

The agency stated that inquiries into community transmission were still ongoing.

The vaccine-derived poliovirus is a known, albeit rare, concern worldwide in countries with low immunization coverage, whereas this kind of incident is practically unheard of in Britain. It can lead to outbreaks, and cases have recently been documented in Israel and Ukraine.

In countries like Yemen and Nigeria, outbreaks are more frequent.

The last occurrence of polio in the UK occurred in 1984, and as of 2022, imported outbreaks are expected in Malawi and Mozambique. “Wild” polio is currently only found in Afghanistan and Pakistan.

Tedros Adhanom Ghebreyesus, the director-general of the World Health Organization, stated that the organisation was coordinating the response with the UK.

To stop polio, investment, vaccine, and surveillance are essential, he tweeted.