A resurgence of polio outbreaks in East Africa could frustrate the global campaign to make the world polio-free by 2018.

In the past eight years, fresh outbreaks have been reported in Kenya, Somalia and South Sudan. In Uganda, Rwanda and Tanzania polio cases were recorded almost a decade ago.

Poliomyelitis, an infectious viral disease, commonly called polio, causes temporary or permanent paralysis. The infection affects children and young adults. The virus enters the nervous system and infects nerve cells that control muscles, causing paralysis, often of the legs.

It is an incurable disease whose symptoms, even though impossible to detect, include fever, fatigue, nausea, headache, nasal congestion, sore throat, cough, stiffness in the neck and back, and pain in the arms and legs.

In its most dangerous form, the polio virus attacks the brain and the respiratory system, creating complications that sometimes result in death.

Last month, South Sudan announced that it had confirmed three cases of poliomyelitis after laboratory tests at the Kenya Medical Research Institute in Nairobi.

Two of the infections were in children, aged two and eight, living in Aweil South County, Northern Bahr el Ghazal State, which borders Central African Republic. The other case was that of a two-year old girl from Ikotos County in Eastern Equatoria State, which borders the Democratic Republic of Congo and is near Kenya and Uganda.

The government declared the outbreak a national health emergency and mobilised partners to conduct additional polio vaccination campaigns in Upper Nile, Jonglei, Eastern Equatoria, Central Equatoria and Unity states that were considered most at risk.

“As long as polio exists anywhere in the world, every unimmunised child is at risk,” South Sudan’s Minister of Health Dr Riek Gai said.

The last time the country reported an outbreak was in 2009.

With 191 polio infections reported in Somalia — mainly attributed to inability by health workers to immunise children owing to the country’s instability and insecurity — neighbouring countries see it as the source of the infections.

“The polio cases in Kenya are imported from our neighbour, Somalia. The infections were at Dadaab camp that is home to thousands of refugees from Somalia,” said Dr S. K. Sharrif, Director of Public Health in Kenya.

Lack of access to routine immunisation in Somalia has created the largest known reservoir of unvaccinated children in a single geographic area in the world. The total number of Somali children who had never been vaccinated between 2008 and 2012 was estimated to reach a million.

This left a large segment of the population vulnerable to polio, which quickly infected children and adults. This is despite Somalia being polio-free since 2007.

Somalia’s immunisation campaigns have also been frustrated by the terrorist group Al Shabaab’s propaganda, urging citizens to boycott the vaccination.

In May and June, the Somali government led a polio immunisation campaign with funding from Japan which targeted more than one million children aged 10 and under. The campaign was however derailed and watered down as Al Shabaab spread propaganda about the vaccine that put off parents.

The spread of the virus in the region is further aided by a highly mobile population with frequent travel across borders for cultural, social and economic reasons.

The infections in Kenya are restricted to the Dadaab Refugee Camp and adjoining communities. Dadaab has offered the optimum environ for the virus as highly infectious polio is spread by person-to-person contact, exacerbated by poor sanitation and lack of clean water.

The border areas of Kenya and Ethiopia are at greatest risk due to low routine immunisation coverage and the high levels of population movement, including large numbers of Somali refugees.

Again, since the origin of the current scare is a refugee camp, movement of refugees across the country could contribute to the spread of polio to the unaffected regions.

The most recent vaccination campaign in Kenya took place from August 17-21 and targeted 5.3 million children under five years and adult populations in about 22 counties.

READ: UK to fund polio vaccination in Kenya and Somalia

The vaccinations also complement previous efforts by offering booster doses to all children aged five years and below. Adults in Garissa and Wajir counties were vaccinated as well. The Ministry of Health plans to take the campaign nationwide from November to December.

In Rwanda, no new infections have been reported since 1993. This could be due to its low population density a far less mobile population. Nonetheless, polio vaccination is on-going.

Between July and October, Uganda rolled out a polio immunisation campaign that targeted about 2.1 million children especially those in border towns that are at risk of polio. Plans are also under way to carry out more campaigns in December.

In Tanzania, until recently, there was concern on the possibility of the disease spilling in through its border with the DRC. Consequently, as of 2008, immunisation was undertaken and continues to date.

It is therefore clear that polio is back, and is spreading through the region.

According to Dr Sharrif, “one strain of the virus —the Wild Polio Virus —has been isolated in Somalia, Kenya and Ethiopia.”