What is hindering the complete eradication of polio in Africa?
A nurse vaccinates a baby in Accra, Ghana, in 2020. Image is public domain
By Keletso Thobega
As of August 2020, Africa was declared free of wild poliovirus, a disease that had previously paralyzed thousands of children across the continent each year. This was a major milestone in the fight against polio, which began with the World Health Organization's Global Polio Eradication Initiative in 1988. This initiative led to a 99 percent decrease in new polio cases globally.
However, a new vaccine-derived mutation of this virus has emerged in Southern Africa, largely linked to low immunization coverage.
In an online interview with Global Voices, some health experts working on the continent highlighted several challenges hindering the complete eradication of polio. They emphasized that successful eradication efforts must go beyond vaccination campaigns to include strengthening supply chain systems, ensuring that polio education and vaccines reach even the most remote and rural communities across Africa.
Village Reach, a non-profit organization that focuses on improving health products and services’ accessibility in low-income and low-resource communities, shared insights on why and how they strengthened their supply chain systems.
Luciana Maxim, director of Health Supply Chain and Lab System Strengthening at Village Reach, told Global Voices that at the end of 2021, they received funding from the Global Polio Eradication Initiative (GPEI) to conduct national assessments of the lab sample referral and transport system for polio in several countries across Africa. According to Maxim, many areas in Africa — particularly rural areas — have poor transport infrastructure, which makes it challenging to reach the communities.
For example, in some areas, some roads have potholes or are unpaved, making it difficult for vehicles to get there. In these places, healthcare workers must find other ways to distribute vaccines, which might take significant time or money, such as through bicycles or helicopters.
The same logistical challenges occur regarding the timeliness and quality of transportation for lab samples, including human and environmental samples suspected of polio. These challenges make it difficult for healthcare workers to meet WHO guidelines that infected samples should be transported to a national or international polio lab within three days of specimen collection.
Tsedeye Girma, UNICEF’s global polio outbreak response coordinator, told Global Voices that depending on the context, they used various modes of transport to get polio vaccines to the most remote health facilities. “This includes refrigerated trucks, motorcycles, boats, pack animals, and also by foot,” she said. She added that in some countries, like Malawi and Mozambique, they have even used drones to deliver vaccines.
Girma detailed how the recent vaccine-derived polio cases in Southern Africa were swiftly contained:
Once wild polio was detected again particularly in Malawi and Mozambique in early 2022, everyone went into emergency mode to contain these outbreaks. It was imperative to get samples to the labs as soon as possible, to raise awareness at the community and health worker level, and to catch up all children on their routine immunizations post-COVID19. We were part of these efforts, and the wild polio outbreaks were contained quickly that same year, she noted.
Maxim pointed out that 13 out of the 15 countries where they have been working since have experienced vaccine-derived polio outbreaks. A vaccine-derived poliovirus (VDPV) is a rare strain of poliovirus that evolves from the weakened live virus used in the oral polio vaccine (OPV). This live virus is designed to stimulate the immune system and build protection against polio. However, if it circulates in under- or unimmunized populations for long enough or replicates in an individual with an immune deficiency, it can mutate and regain the ability to cause disease.
Maxim added:
We quickly realized that, in order to help suppress outbreaks, we need an integrated approach that ensures samples for all outbreak-prone diseases reach labs within days. We took every opportunity to integrate resources, staff and data across diseases and across health system functions.
Girma said it is critical to build a decentralised presence and ties with communities.
She explained:
We take a community-centric approach in engaging local communities as active partners in the fight to end polio. We recruited and trained thousands of local community members including traditional leaders, religious leaders, polio survivors, women groups, youth, and other community influential people to work as polio outreach workers and mobilizers.
Most households in Africa have women as breadwinners, and the majority of polio community mobilizers have been women, which is critical in areas where cultural norms restrict their male healthcare workers from entering households with only women.
This approach makes all the difference in getting the message across and ensuring children get vaccinated, Girma added.
To enhance the reach of the vaccination campaigns, UNICEF and other stakeholders have made efforts to craft messages in a multitude of local languages, but the language barrier in polio vaccine campaigns persists. These messages are often broadcasted through megaphones by town announcers and mobile public announcement vans that traverse from one community to another.
Vaccine misinformation also remains a significant barrier to reaching children. Girma said that community mobilizers play a key role, addressing parents’ and caregivers’ concerns about vaccines during visits.
“We also use social listening tools to track and counter false information about vaccines both online and offline. UNICEF’s digital community engagement program mobilizes over 70,000 online volunteers worldwide to counter misinformation and provide accurate and timely information about vaccines.” Some of the common falsehoods they encounter include claims that vaccines are painful and cause illness, weaken the immune system, are designed to harm young people, or are not culturally or religiously acceptable.
In a message to mark World Polio Day 2024, WHO Regional Director for Africa, Matshidiso Moeti, reported that 134 cases of polio type 2 had been detected in 2024 alone as of September 5. The circulating variant was identified in Burkina Faso, Cameroon, the Central African Republic, Chad, Mali, Niger, and Nigeria.
As polio eradication efforts continue, Maxim and Girma express hope that governments, the private sector, and non-governmental organizations will collaborate to combat vaccine misinformation. They also stress the importance of prioritizing funding to strengthen supply chain systems, ensuring equitable access to vaccines and healthcare services across the continent.