COVID-19 public health measures threaten efforts to eliminate polio, say experts

Strategies adopted in 2020 to fight COVID-19 around the world have impacted routine vaccination against poliomyelitis and even measles.

In 2020, about 7.7 million children did not receive the life-saving first dose of diphtheria-tetanus-pertussis, measles and polio vaccines as a result of COVID-19 lock down measures, the World Health Organization (WHO) says in an article published in 2021.

According to WHO, missed vaccination in Africa compared to the previous year rose to about ten percent because of the disruption of health services due to the pandemic.

"In March 2020, when the COVID-19 pandemic was officially declared, all service delivery was suspended in countries, including polio campaigns and the fight against other vaccine-preventable diseases [such as measles and yellow fever]," Modjirom Ndoutabe, polio program coordinator at the WHO regional office for Africa, told SciDev.Net.

"Countries have continued to isolate the poliovirus, either from target children or from the environment. In the countries affected by COVID-19 and polio epidemics, we have seen that vaccine responses were slowly executed in 2020 and 2021, and this allowed the virus to circulate intensely in the African region," he added.

Phobia

In Cameroon, for example, the pandemic period was marked by a resurgence of measles and poliomyelitis.

"Measles spread from 44 health districts in 2019 to 80 districts in 2020," said Shalom Tchokfe Ndoula, the permanent secretary of the Expanded Vaccination Program in Cameroon.

"In March 2020, when the COVID-19 pandemic was officially declared, all service delivery was suspended in countries, including polio campaigns," said Modjirom Ndoutabe, of WHO Africa. "In 2021, the response measures put in place made this number reduce to 31. In 2022, however, the number shot up and approximately 60 health districts were affected," he added.

Ndoula said, "Cameroon went from having four cases of the poliovirus in 2019 to having 16 cases in 2020." He said while the number of cases reduced from 16 to six in 2021 and then to two in 2022, any case of derived polio is a "sign of insufficient immunity within the communities."

The situation was similar in Senegal where vaccination campaigns halted because of the public health measures—including school closures—put in place to slow down the spread of COVID-19. This measures, Ousseynou Badiane, the coordinator of the Expanded Vaccination Program in Cameroon, resulted in a drop in attendance at health facilities.

"Health personnel were practically occupied with the fight against COVID-19 to the point that other programs were neglected," Ousseynou said.

In Guinea, the period preceding the COVID-19 years had better vaccine coverage than the period of the virus.

"We analyzed the vaccination data from the COVID-19 period to those for the period of 2018 or 2019, we realized that there was a slight drop in vaccination coverage," says Mamadou Dian Bah, head of the planning and mobilization department at the Expanded Vaccination Program in Guinea.

Fake news

Rumors and fake news on vaccination against COVID-19 have also caused many families to refuse childhood vaccination.

Ndoula told SciDev.Net that vaccines campaigns also suffered a setback too. "Due to misinformation, various vaccination campaigns encountered unusual difficulties, particularly refusals to receive vaccines.

"The main obstacles being rumors that COVID-19 vaccines will be given under the guise of the usual vaccine campaigns, children would be discreetly vaccinated against COVID-19, harmful substances will be snuck in through vaccine campaigns and children would be sterilized," he said.

Ousseynou Badiane, the coordinator of Senegal's Expanded Vaccination Program, also agrees that vaccination programs suffered from fake news and that this led to vaccine hesitancy.

"When we started the COVID-19 vaccination, there were a lot of people who did not want to be vaccinated against other genes (viruses), especially those for infants," Ousseynou, told SciDev.Net.

He said people begun to believe other vaccines were a masked way of giving the COVID-19 vaccine to children. They believed that COVID-19 vaccines are dangerous.

Ousseynou added that vaccination campaigns against yellow fever, the derived polio and a selective campaign against measles organized during COVID-19 were impacted and a lot of vaccine refusals occurred.

"Fake news had an impact, even if it was not very big, on these campaigns because we registered a lot of cases of refusal during these campaigns," he said.

Some mitigation

In the midst of the pandemic, WHO was keen to strengthen "interpersonal communication to encourage parents to have their children vaccinated against polio and measles," said Modjirom Ndoutabe.

It was this communication strategy that enabled Guinea mitigate the impact of COVID-19 on routine vaccination and maintain vaccination coverage "at an acceptable level," Mamadou Dian Bah told SciDev.Net.

For Senegal, Ousseynou says that the Expanded Program on Immunization adopted some "corrective measures" to mitigate the impact of the pandemic on the health system.

"We raised the vaccination coverage a little and brought it to satisfactory levels," he said.

In Cameroon, according to Ndoula, the health authorities developed guidelines that help health personnel know how to continue providing vaccination services while protecting themselves and others against COVID-19 was created.

The health personnel also now know how to effectively communicate with the parents, said Ndoula.

Other strategies such as mobile campaigns were organized in urban areas "to sensitize populations on the benefits of vaccination and the risks that children who are not vaccinated face," he said.

Ndoula added that advanced strategies have been put in place in under-vaccinated communities to bring the vaccination offer closer to the populations.

"These advanced strategies include door-to-door outreaches and intensified vaccination activities in some regions and districts of the country to catch up with children who have missed their vaccine doses," Ndoula explained.

Sensitization

In 2022, the WHO implemented response plans "which enabled a dozen countries to stop the circulation of all types of poliovirus," Modjirom Ndoutabe, polio program coordinator at the WHO Regional Office for Africa, tells SciDev.Net.

However, there is still a risk of spreading these infectious diseases, especially if the viruses circulate in areas where children are not vaccinated.

Modjirom said that strengthening communication is essential to enable parents adhere to the various initiatives to eradicate or control diseases preventable by vaccines.

"Routine vaccination should be reinforced by the implementation of integrated multi-antigen mini-campaigns," he recommends.

Badiane says that routine immunizations must be prioritized.

"We were almost at the final phase of eradicating poliomyelitis; we were moving towards the elimination of measles… It is thanks to vaccination that we had these achievements. To prevent these diseases from coming back, emphasis must be placed on routine vaccination," he said.

Ndoula added that providing people with information on vaccination and the vaccination schedule for children of 0 to 23 months, could contribute to the eradication polio and measles.

He recommends adapting health services to the life style of community members.

"Health services will have to adapt to the habits of the community, even if it means offering vaccination services during office hours to give all children the chance to receive their doses of vaccines," he added.