Is Africa Truly Free of Wild Polio?

Public health worker in Africa distributing vaccines

Utibe Effiong, MPH ’14 and Uju Okeke

Utibe Effiong, MPH ’14 and Uju Okeke

This article first appeared on Africa Portal.

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In August 2020, the World Health Organization (WHO) certified the African region as wild polio-free after four years without a case on the continent.

The announcement came after Nigeria—which has long battled challenges such as vaccine hesitance, political instability, ethnic violence and rough terrain with regard to eradication of the disease—became the last African country to be declared free of wild polio. Less than a decade ago, Nigeria accounted for more than half of all global cases. The last case of wild polio in Nigeria was reported in 2016.

Polio, or poliomyelitis, is a disabling and life-threatening disease caused by the poliovirus. The virus spreads from person to person and can infect a person’s spinal cord, causing paralysis. In the early 20th century, polio was one of the most feared diseases in industrialized countries, paralyzing hundreds of thousands of children every year. Soon after the introduction of effective vaccines in the 1950s and 1960s, polio was controlled and practically eliminated as a public health problem in those countries.

Challenges such as political instability, ethnic violence, and rough terrain persist.

It took longer for polio to be recognized as a problem in the developing world. Lameness surveys during the 1970s revealed that the disease was also prevalent in developing countries. As a result, during the 1970s, routine immunization was introduced worldwide as part of national immunization programs, helping to control the disease in many developing countries.

Rotary International launched a global effort to immunize the world’s children against polio in 1985. The establishment of the Global Polio Eradication Initiative (GPEI) followed in 1988. These efforts led to a 99% decline in the global incidence of polio. However, social, cultural, religious, and political factors hindered the eradication of wild polio in Nigeria.

Nigeria’s Challenges

The controversy surrounding the safety of the oral polio vaccination in northern Nigeria contributed immensely to the delay that led to continued infectivity of children with the poliovirus. Some of the delays to eradication were attributable to eccentric views upheld by parents who refused vaccination for their children due to religious, traditional, and superstitious beliefs. That is in addition to the initial vaccine boycott that followed rumors of contaminants likely to be carcinogenic and general misunderstanding about the possibility of developing polio after vaccination. Additionally, there was a lack of community involvement, information dissemination and disregard for cultural beliefs and norms.

Polio eradication in Nigeria took so long because challenges such as political instability, ethnic violence, and rough terrain persist. The Boko Haram insurgency claimed the lives of nine polio vaccinators in high-risk northern Nigeria. The supplementary implementation activities in localized areas continue to be inefficient, while anti-vaccine sentiments still echo within the communities. Children who live in border settlements are known to carry a different strain of poliovirus. That highlights the possibility of cross-border spread. In these hard-to-reach areas, only about 53% of children aged 12-23 months received three doses of the polio vaccination.

So we must pause to ask just how accurate the data on wild polio in Africa is.

Four cases of wild poliovirus infection (WPV1) were detected in July 2016 in a remote and security-challenged area of Borno State in northeastern Nigeria. This discovery was made two years after the WHO removed Nigeria from the list of polio-endemic countries and put Nigeria back on the list as having a strain of WPV1 that was in circulation but undetected since 2011. In 2012, cases appeared in three countries that had reported eradication. The virus strain involved was determined to have been imported from Nigeria.

An initiative between the national polio program and the Nigerian military to reach inaccessible areas —called the Reaching Every Settlement Initiative—was able to provide immunizations to approximately 99.6% of all partially accessible settlements at least once by February 2020. This means that some children are yet to be reached.

Polio anywhere is polio everywhere.

With laboratory poliovirus containment, the destruction of all potentially infectious poliovirus substances has taken place in all 47 African countries where cases were present. In 2018 South Africa received an initial certificate of participation per the Containment Certification Scheme to retain poliovirus infectious materials in their laboratories. Some laboratories opt to retain infectious agents for the purpose of research. The certificate of participation is awarded only to facilities in countries that have demonstrated compliance with the required safeguards for the containment of polioviruses.

Hopefully, we will not see a repeat of the case of Dr. Henry Bedson who, in 1978, stored the smallpox virus in his laboratory at the University of Birmingham that led to the death of a medical photographer. Janet Parker, who occupied the darkroom above the laboratory, was infected with the smallpox virus two years after its eradication. This tragedy underscores the dangers of stored viruses due to their inadvertent potential to cause harm.

It is important to remember that polio anywhere is polio everywhere.

Despite interventions with childhood immunizations, sub-Saharan Africa still records over two million deaths from vaccine preventable diseases (VPDs) annually. Nigeria remains a contributor to global childhood deaths. Although significant factors such as child, parental, socioeconomic and political barriers continue to impede immunization programs, applying the aggressive approach taken on polio to other VPDs will increase access to routine immunizations.

A synergistic strategy is necessary to address the peculiarities of the region, that will assure progress towards the prevention of the mortality and morbidity associated with polio and VPDs. As seen with polio eradication programs, continuous, tenacious and concerted efforts will be needed to ensure the success and efficacy of public health programs.

About the Authors

Utibe Effiong, MPH ’14, MD, is an internal medicine physician, public health scientist, and clinical assistant professor of medicine at Central Michigan University, USA. He is also a Senior Fellow at the Aspen Institute. Read more about Dr. Effiong in A Desire to Be More: How Public Health Connects Medicine to Patient Communities.

Uju Okeke, MBBch, MPH, is an Ambassador of the Texas A&M Opioid Task Force and Ambassador of SPH Health and Wellness School of Public Health.