First outbreak of highly infectious polio detected in UK since 1984

[Gefn]

POLIO is spreading in the UK for the first time in decades, officials claim.

Health bosses urged Brits to check their children's jabs are up to date after picking up signs of the virus being passed between individuals.


Experts have detected the same bug in London sewage samples since April – a clear signal of a community outbreak.

No cases have yet been confirmed in the UK and the UKHSA said samples were found in East and North London.

This, chiefs say 'suggests it is likely there has been some spread between closely-linked individuals'.

https://www.the-sun.com/health/5615177/first-outbreak-highly-infectious-polio-uk-signs/

[Kamaji]

Oh boy.  We do not need a polio outbreak.  That is definitely a nasty disease.

[Wingnut]

Immigrants. 

[PeteS in CA]

Reading the article, it looks like the initial source was someone who received a weakened virus polio vaccine, which works by the recipient actually being infected and thereby developing antibodies against polio. This usually works well enough, but with poor hygiene or inadequate sanitary facilities, an outbreak of the weakened virus could (and on occasion, has) occur.

This is an issue that protein sub-unit, viral vector, and mRNA vaccines do not have.

[PeteS in CA]

This article gives more details, https://arstechnica.com/science/2022/06/poliovirus-may-be-spreading-in-london-virus-detected-in-sewage-for-months/ :

Briefly, there are two types of polio vaccines: the attenuated oral vaccines and inactivated vaccines. Many high-income countries that are considered polio-free—including the UK and the US—use the inactivated vaccines, which do not have viruses capable of replicating or spreading. These vaccines are highly effective at preventing paralytic polio, but they do not produce high levels of local immune responses in the gut. So, if a vaccinated person encounters wild poliovirus, the virus may still be able to replicate in their gut and spread. In areas affected by wild polio outbreaks, this means that the virus can continue spreading.

Oral polio vaccines, on the other hand, can not only prevent paralytic polio, they can also produce strong local immune responses in the gut that block the virus from replicating there, thus disrupting its spread. These vaccines can also be more than five times cheaper than the inactivated kind. For all of these reasons, oral polio vaccines are the predominant vaccines used in the long, drawn-out battle to eradicate wild polio. Currently, wild polio is still found in Afghanistan and Pakistan, and Malawi and Mozambique have recently reported single cases.

But, one of the downsides to oral polio vaccines is that vaccinated people can shed the attenuated vaccine virus in their stool for several weeks after vaccination. If this happens in a community with poor sanitation, hygiene, and low vaccination coverage, the vaccine virus can spread from person to person. Over time, as the vaccine virus spreads to more people, it can pick up mutations that make it more like wild-type polio, allowing it to regain the ability to cause disease and, in rare instances, paralysis in unvaccinated people. At this point, the mutated vaccine virus gets dubbed "vaccine-derived poliovirus" or VDPV. Recently, VDPV cases have been reported from several African countries and Israel.