Polio is becoming harder and harder to find. An amazing feat thanks to vaccines and joint efforts of government agencies, local communities, organizations and more. 2019 marked very monumental moments in the movement towards complete eradication of Polio in the world. It marked the 25th anniversary of the Americas’ polio free status. Most importantly the Global Certification Commission’s certified the eradication of the WPV3 which is a a wild type poliovirus. Two out of three wild type polioviruses are now eradicated. WPV2 was eradicated in 1999. WPV1 is now only present in circulation in Afghanistan and Pakistan.
This is a worldwide movement. The eradication of polio relies on people receiving their vaccinations. It is the vaccinations that will protect the children and secure herd immunity from the disease. The opportunity to eradicate polio is at our fingertips and we must not let this opportunity slip between them. Although you might not live in a country where polio is circulating you are still a major player in the end of the disease. By receiving your vaccination you are closing the gaps and ensuring all children are protected. You never know where you will travel, or who you will talk to or come into contact with. Do us all a favor and get yourself and your loved ones vaccinated. Do it for the kids and do it for those who cannot protect themselves.
The Vaccines Behind It:
There are two vaccines for polio:
- Oral Polio Vaccine (OPV)
- Bivalent: targets type 1 and 3
- Trivalent: targets all 3 types
- Inactivated Polio Vaccine (IPV)
OPV is an oral drop and is the main preventative measure against polio in many parts of the world. OPV is not commonly used and has been no longer licensed in the US since 2000 because of the link to vaccine derived poliovirus. Circulating Vaccine Derived Poliovirus (cVDPV) which stems form a mutated version of OPV which can spread from person to person and cause paralysis. This type of polio is often derived from the trivalent vaccine because it is caused by a mutation in the type 2 vaccine derived virus. There is now a call to switch to bivalent OPV in countries where OPV is administered because it is more powerful against 1 and 3 and does not have severe risk of paralysis. Since the there is no more wild type 2 polio in the world there is no need for a vaccine to target type 2 especially when there are complex and serious medical complications that can arise from them. It is the trivalent OPV vaccine that could prevent the full eradication of the poliovirus. Ironic, how the vaccine could stand in the way of its elimination. But that shows the importance of medical advancements and research as we understand more about viruses we are able to more efficiently eradicate them.
Only OPV is linked to vaccine derived poliovirus. They are extremely rare and occur because the supplemental vaccines are poorly administered where there is a high risk for polio. Notice, in the picture below how cVDPV is present in the Middle East, Africa and southeast Asia. All locations with very low vaccination rates for the poliovirus as well as limited access to adequate healthcare systems to administer proper vaccines. IPV does not cause vaccine derived poliovirus which is a supporting reason why the United States has been stayed poliovirus free for 25 years.
IPV is just as effective as OPV. IPV is a booster shot and requires multiple administrations over time. Two doses provides 90% immunity while three doses provide 99% immunity. This is how we are going to eliminate poliovirus. Is it doing our job as humans to vaccinate ourselves and our children. The less people vaccinate the more prevalent a disease becomes. The work of modern vaccines has put us too far in the movement of eradication of polio for us to go back now simply because of an anti-vaxx movement based on false claims.
The Good, The Bad, The Microbiome 