In 1996, African leaders committed to the Global Polio Eradication Initiative (GPEI) when South Africa, led by then-President Nelson Mandela, launched the Kick Polio Out of Africa campaign. Twenty-four years later, on August 25th of 2020, Africa has finally been declared wild polio free.
The GPEI is a consortium led by the World Health Organization (WHO) in partnership with Rotary International, the US Centers for Disease Control and Prevention (CDC), United Nations Children’s Fund (UNICEF), the Bill & Melinda Gates Foundation and Gavi, the Vaccine Alliance. This initiative began in 1988 and aimed to eliminate the transmission of polio worldwide by working alongside national governments and local leaders.
Polio stands for poliomyelitis — an infectious disease caused by the poliovirus, which mostly affects children under the age of five. The poliovirus is transmitted from person-to-person through the ingestion of fecal matter, which can be found in contaminated water sources, food or even soil. Viruses like polio thrive on communities with poor sanitation and hygiene practices, which is why impoverished nations and developing countries have suffered most from the disease. Infection with poliovirus is initially established at the oropharyngeal and intestinal mucosa membranes. From there, viruses will replicate and shed, reaching the bloodstream. Viral shedding in the feces of an infected individual is what primarily propagates transmission of the poliovirus. Most infections subside at this stage and the majority of individuals are asymptomatic or have minor non-specific symptoms which include fever, sore throat and general discomfort. However, some viral particles may take a detour and infect other tissues like muscle, fat or — in the worst-case scenario — motor neurons of the central nervous system.
Poliomyelitis constitutes the neurological phase of a poliovirus infection and occurs only in one to two percent of all infections. When the nervous system is compromised, the patient will develop flaccid muscle paralysis, and that is where the real danger of the poliovirus lies. Paralysis can affect only the limbs when the virus targets the spinal cord, or it can affect breathing muscles and the heart if the virus targets the brain — ultimately leading to death due to respiratory and cardiac failure. This phase is supposedly an accidental diversion from the natural course of the virus since it does not seem to contribute to viral transmission in any way. Although the percentages may seem low the actual numbers can be extremely high because the poliovirus is highly contagious. When the GPEI was launched in 1988, polio paralyzed more than one thousand children worldwide every day.
The poliomyelitis incidence rate has decreased by 99% since then, thanks to the tremendous effort of everyone involved in the vaccination and surveillance programs. These campaigns were led by health care workers and polio survivors working with the GPEI. Although there is no cure for polio, we currently have two different highly effective vaccines against the virus. The most prevalent one is the inexpensive and easy to administer oral polio vaccine (OPV), which consist of an attenuated (weakened) strain of the virus and was widely distributed in Africa. The alternative is the injectable inactivated polio vaccine (IPV), commonly administered in combination with other vaccines.
The WHO African Region is the fifth region to achieve the label of wild polio free in 2020, four years after the last reported case of polio in Nigeria. It followed South-East Asia (2014), Europe (2002), the Western Pacific Region (2000) and the Americas (1994). Wild poliovirus remains endemic in only two countries of the Eastern Mediterranean Region: Afghanistan and Pakistan.
The eradication of polio has not only been a fight against a natural disease but also a fight against the worst side of humanity. What has been halting the progress towards a world free of polio is a combination of war, religious extremism and anti-vaccination campaigns. Taliban groups in Afghanistan and Pakistan have been campaigning against polio vaccines for a long time. They believe these vaccines are a scheme designed by the United States of America to sterilize the muslin population. These campaigns took the form of violent assaults on health care workers and facilities, a tactic which spread to other terrorist groups in Nigeria. Anti-vaccination conspiracy theories gained support since it was reported in 2012 that the Central Intelligence Agency ran false vaccination campaigns in Pakistan, in order to track down Osama Bin Laden. These false campaigns made irreparable damage to the public’s trust in health care workers and vaccines. Both countries are still rebounding from this and we can only hope that they do so.
The challenges facing the Global Polio Eradication Initiative today include the ongoing transmission in the Eastern Mediterranean and the recent outbreaks of vaccine-derived polio — a rare but dangerous consequence of the attenuated virus present in oral vaccines, which may mutate and regain the ability to spread and cause disease. Additionally, there is also the impact that the COVID-19 pandemic had on health care facilities and ongoing vaccination campaigns, which have been temporarily halted. These obstacles however do not undermine the hallmark that is an Africa free from wild polio and the progress that has been made over the last years. We are closer than ever to a polio-free world.
