Polio emergency response teams in Malawi are ramping up disease surveillance and deepening investigations after the country detected a case of wild poliovirus—the first of its kind in Africa since 2016. Determining the extent of the risk and searching for any further cases are among the crucial steps for an effective response to halt the virus and protect children from its debilitating impact.
The African region was declared and certified as free of indigenous wild polio in August 2020 after eliminating all forms of wild poliovirus. Laboratory analysis linked the strain detected in Malawi to the one circulating in Pakistan’s Sindh Province in 2019.
In January 2022 soon after Malawi received preliminary results of poliovirus, the Ministry of Health, with support from World Health Organization (WHO), swiftly launched response measures, collecting additional stool samples from contacts of the index case, and shipping them for further analysis, as well as actively searching for possible new cases. The country declared an outbreak of wild polio on 17 February following confirmation of the virus type. This is the first case of wild poliovirus in Malawi since 1992.
Within days of the outbreak being declared, expert teams deployed to the country to support key response measures including setting up a fully functional environmental surveillance system to complement clinical acute flaccid paralysis surveillance for possible polio cases. This entails identifying suitable wastewater locations to serve as environmental surveillance sites and training responders at national and local levels to collect and package samples for shipping and analysis.
Environmental surveillance for polioviruses has now been established in six sites in two districts. These include Lilongwe District that encompasses the capital Lilongwe where the initial, and so far the only case, was detected. Other sites are in Blantyre, Mzuzu and Zomba cities.
The polio response teams have also undertaken a risk assessment, which includes detailed disease investigation, epidemiological surveillance assessment as well as analysing factors that can hinder or ease response operations. Additionally, educating and informing the media and the public about polio is ongoing, so they can also report any suspected cases.
To support the country team, experts from the WHO Regional Office for Africa were deployed within days of Malawi declaring the outbreak. The surge team of six includes a coordinator, a technical and operations expert, surveillance experts and a data manager. The WHO team is part of a broader multi-partner Global Polio Eradication Initiative (GPEI) support to the country.
“We have all the necessary tools and all the necessary tactics to successfully stop this outbreak,” said Dr Janet Kayita, acting WHO Representative in Malawi. “Malawi has been polio-free before and can rapidly be so again. The key is to optimize operations and now ensure that every child is reached with the life-saving polio vaccine.”
Malawi has scheduled a mass supplemental polio vaccination response targeting under-five children, using the Bivalent Oral Polio Vaccine recommended by WHO and the GPEI partners for wild poliovirus (type 1). Four rounds of polio vaccination campaigns are planned. All the neighbouring countries – Mozambique, Tanzania and Zambia – have been alerted and are planning to conduct immunization campaigns as well.
“The quality of the vaccination campaign is essential to interrupt transmission of poliovirus from child to child. Therefore it is critical to ensure that the vaccination rounds reach every child,” said Deputy Minister of Health, Honourable Enock Phale. “We ask all our political leaders, religious leaders and community leaders to support the government in encouraging our communities to take part in the polio eradication activities by taking their children for the routine polio immunization.”
An immediate-response public awareness campaign has been launched by the Ministry of Health and partners to alert the public of the outbreak, describe the planned response and provide information about polio and the vaccine.
Malawians are treating the outbreak with due urgency.
“I am ready to do whatever it takes to protect my children including getting the polio vaccine. We do not want to see polio paralysing children again as it was 30-plus years ago,” said a resident of Area 24 in Lilongwe, who wished to remain anonymous.
Polio is a highly infectious disease caused by a virus. It invades the nervous system and can cause total paralysis within hours, particularly among children under five. The virus is transmitted from person to person mainly through faecal matter or, less frequently, through contaminated water or food, and multiplies in the intestine. While there is no cure for polio, the disease can be prevented through administration of a safe, simple and effective vaccine.
“Malawi is now considered a polio-affected country. We are working tirelessly with the government and our GPEI partners to reverse this. The WHO African Region’s status as wild polio-free remains intact. However, our work now is to quickly prevent any in-country spread of wild poliovirus and keep children safe,” said Dr Christopher Kamugisha, the GPEI Coordinator.