The World Health Organization (WHO) published a report last week, which recorded nine new polio cases that were caused by the vaccines in four African countries in Nigeria, Central African Republic, Angola and the Congo.
A total of 16 countries have had similar outbreaks. That includes cases in other African counties, and in Asia in places such as the Philippines, China, Myanmar. It’s risen the count of polio cases caused by vaccines to 157.
Afghanistan and Pakistan, the two countries where polio continues to be endemic, have a reported 107 cases of wild polio.
According to the Associated Press, all the current cases where people have contracted polio through the vaccine, have been caused by a Type 2 virus, whose wild form has been eliminated since 2015.
Following the eradication process, the live oral vaccine was created. WHO and other organizations have relied on oral polio vaccines, which requires two drops per dose, because they are less expensive and can be easily administered. Western countries are known to use a more expensive injectable vaccine, which contain an inactivated virus that is incapable of actually causing polio.
While the oral vaccine did help some, it gained strength to the point that it can now cause paralysis in the same way as the wild disease. Polio, of which there are three distinct strains that each requires a different vaccine, is known to spread through contaminated food or water, and is most common to strike children under 5. The highly infectious disease has a 0.5 per cent change of leading to paralysis, but it can also lead to death when breathing muscles are crippled.
In April 2016, organizations around the world pulled the vaccines that contained all three strains of the polio virus. It was replaced by a new vaccine for Types 1 and 3. If a Type 2 virus were to pop up, as a rogue, the plan was to quickly attack the outbreak, with the expectation that Type 2 vaccine polio would eventually die out relatively quickly.
That hasn’t been the case. When Type 2 outbreaks occur, health officials vaccinate kids near the outbreak with a vaccine that protects only against Type 2. While performing these mop-ups, it gives the virus another chance to enter an environment, sometimes in a community where people haven’t been immunized, which could spark another outbreak.
To eradicate polio, more than 95 per cent of a population needs to be immunized, according to the Associated Press.
“Vaccine-derived poliovirus is moving across Africa, with vaccine-derived Type 2 poliovirus spreading uncontrolled in West Africa, bursting geographical boundaries and raising fundamental questions and challenges for the whole eradication process,” writes a report by WHO’s Independent Monitoring Board.
The same reports notes that officials have been “failing badly”, while the attitude of WHO and other partners are “relaxed” as they try to execute their approved polio goal of stopping all vaccine-derived outbreaks within 120 days of detection