What you need to know about the disease

Polio can be eradicated and there are effective vaccines against it. (Representation)

Birmingham, United Kingdom:

The British Public Health Agency (UKHSA) has announced a recurrent national outbreak of poliovirus in sewers north and east of London, as monkeys are expected to pose a new virus threat by 2022. Recurrent positive polio rates indicate the presence of ongoing infection and infection in the area. This came as a surprise as the UK has been declared polio-free since 2003. Here’s what you need to know.

Poliomyelitis (poliomyelitis) is a devastating disease that has historically led to paralysis and death around the world. It is caused by polioviruses, small RNA viruses that can damage the cells of the nervous system.

It is not found in animals, so it can be eradicated like smallpox. And thanks to an effective vaccination campaign, we are getting closer to this goal every year.

There are three types of polio and one type of infection or vaccination does not protect against the other. Type 1 polio continues to cause epidemics, but types 2 and 3 have been successfully stopped by vaccination.

Polio is transmitted by respiratory droplets, but it can also be spread through food or water that comes in contact with an infected person’s face.

Can live for many days at normal temperatures. The remaining recent epidemics have been associated with poor sanitation and inaccessibility of vaccines. Afghanistan and Pakistan are the only two countries where wild polio is still endemic, and targeted programs to stop the spread of the virus to other countries.

The crucial role of vaccines

Vaccines have been important in eradicating polio. In 2021, there will be less than 700 cases worldwide.

In the UK, an injectable polio vaccine is used. It contains the inactivated virus (IPV) and is safe and effective in protecting an immunized person from polio, but is not effective in creating local immunity in the gut, so vaccinated people can still become infected and shed infectious viruses. The signs themselves show.

BTI offers excellent protection for humans, but is not sufficient to control the epidemic in poor sanitation. A live but attenuated polio vaccine (OPV) is ideal for this purpose. OPV equipment is drip-operated and does not require trained personnel or a sterile apparatus to operate, so it can reach more communities.

This vaccine creates a strong intestinal immunity and prevents the spread of wild polioviruses. Because it contains a live virus, it spreads to close contacts of the immunized person and protects them. It is also cheaper than BTI.

The downside of using OPV is that the weakened virus can mutate, and in rare cases it can return to the paralytic-causing variants.

OPV is cleared by our immune system within a few days, but this may not be the case in people with weakened immune systems, as they can carry the virus longer, increasing the chances of mutations. In non-immunized countries, this vaccine can cause polio virus (VDPV). In fact, the virus found in the sewers of London was a type of VDPV 2 derived from the vaccine. There is still no wild poliovirus in the UK.

Vaccinated poliomyelitis can cause asymptomatic infection in people vaccinated with IPV, and it is shed in the feces because there is no local intestinal protection with IPV. Therefore, it can be found in wastewater.

Verification methods are sensitive, but only a positive indicator does not raise the alarm. Type 1 VDPV was recently found in a sewer in Calcutta. This is thought to be due to the importation of the vaccine strain from the body of a vaccinated person whose immune system is weakened.

There are no reports of polio-related polio in the UK.

To prevent the disease, we need to ensure that family members are vaccinated, especially children who have missed a vaccination course due to the COVID pandemic. IPV is safe, free and effective in preventing polio. Unlike vaccines that are available for monkey smallpox vaccines and high-risk groups, IPV is available to everyone in the UK through their GP.A talk

(Author: Zania Stamataki, Senior Lecturer in Viral Immunology, University of Birmingham)

(Disclosure Notice: Dr. Zania Stamataki is funded by the Medical Research Foundation, Innovate UK and BCHRF, and she shares her PhD with AstraZeneca in the iCASE MRC UKRI student program.)

This article was republished in The Conversation magazine under a Creative Commons license. Read the original article.

(Except for the headline, the story was not edited by NDTV staff and was broadcast on a syndicated channel.)


Leave a Comment

Your email address will not be published.