Health
Why London’s Kids Are Getting Polio Vaccine Boosters?
(CTN News) – It was reported in June that poliovirus had been detected in sewage in north and east London between February and May 2022.
Following this, people were advised to vaccinate their children against polio.
As a result of the JCVI’s recommendation on August 10, all London children between the ages of one and nine should receive a further booster dose of the polio vaccine.
Why did the vaccination policy change between June and now?
First, a little background. Poliomyelitis, or polio, is a devastating disease that has historically led to paralysis and death, mostly in children.
It’s caused by an RNA virus (poliovirus) that spreads easily from person to person, usually through feces.
Most poliovirus infections go unnoticed, but a small proportion develop paralysis (paralytic poliomyelitis), which can cause respiratory failure and long-term deformities.
There were two types of polio vaccines developed in the 1950s: a live attenuated vaccine given orally (the Sabin vaccine) and an inactivated vaccine given by injection (the Salk vaccine).
Live attenuated vaccines are based on viruses still capable of reproducing, but weakened so they do not cause disease. Inactivated vaccines, on the other hand, cannot reproduce.
There is high efficacy for both vaccines in preventing paralytic poliomyelitis.
Particularly, the oral vaccine induces strong immunity in the gut, which reduces faecal shedding, and thus transmission.
The oral vaccine can, however, occasionally cause paralysis (about two to three cases per million doses).
As a result, most countries, including the UK, now prefer to use inactivated vaccines. There are still a few countries that use the oral vaccine, however.
Related CTN News:
