More than 4.6 million children have been displaced by the war in Sudan. We met the health workers striving to keep them protected from disease. 

Achok Ajak and her children fled Khartoum after the civil war began. When they arrived in Abyei, South Sudan, in November 2023, Ajak’s daughter Nyanriak was almost three years old and still unvaccinated.

Back in Sudan, Ajak explained, the health facilities had been distant from their settlement, and transport had been costly. When fighting broke out, the roads were suddenly choked with checkpoints, and the risk of travelling them became too high.

But in Abyei, Ajak recalled, “I didn’t think of taking Nyanriak for vaccination to the health facility because she already passed the recommended age for receiving vaccines. I believed the health workers will not vaccinate her.” Moreover, she said, she worried she’d be blamed for negligence.

Then, in early April 2024, a team of health workers conducting a door-to-door immunisation campaign arrived at the locality where Ajak and her children had taken up residence, and struck up a conversation with the mother of three.

“I encourage GOAL to continue with this approach of vaccinating our children. Many children in my community did not receive their scheduled vaccine doses due to insecurity and displacement. I am happy that my child is now fully immunised and protected [...]”

- Achok Ajak, displaced mother of three, Abyei

Nyanriak was identified as a zero-dose child, and, on the same day, given the vaccines that signal her graduation from that unenviable roster: doses of the oral polio vaccine, the pentavalent jab (which protects against diphtheria, tetanus, pertussis, hepatitis B and Hib), and the measles immunisation. The health workers noted down her details and made sure that, over the next two months, she received all of her recommended follow-up doses.

Fleeing danger

Children like Nyanriak, whose childhoods are unsettled by conflict, are legion: more than 4.6 million have been displaced by the Sudan civil war alone, with a million of them having fled across borders. Worldwide, the number of children displaced by conflict and violence reached 47.2 million at the end of 2023.

On the move, these children are likely to be lost to health systems, leaving them exposed even after they escape the line of fire. But in South Sudan, a vaccination initiative specifically tailored to catch up unimmunised kids in conflict and border zones is managing to find and shield them, one by one.

Between December 2022 and June 2024, more than 49,000 children in South Sudan received their first doses of the basic pentavalent vaccine and oral polio drops via REACH, a consortium led by the International Rescue Committee (IRC) and funded by Gavi.

A rising proportion of those children had, like Nyanriak, been acutely vulnerable to outbreaks of vaccine-preventable diseases for years at the point that health workers found them.

The first dose of the pentavalent jab – penta 1, in the technical shorthand – is typically scheduled for babies of six weeks, but REACH’s data shows that in South Sudan the proportion of those doses that have been going to children above age two increased, month to month, over the first five months of 2024.

Navigating the boundary zones

The pentavalent vaccine is important in its own terms, but it’s also an indicator vaccine – a conventional marker for a health system’s ability to reach zero-dose children and bring them into the routine vaccination schedule.

That bar is sky-high in Abyei Special Administrative Area. Abyei is a contested territory on the border between Sudan and South Sudan that plays host to state-armed actors from the rival countries, is dogged by inter-communal conflict and violent crime along important supply routes, and has a tendency to flood. Since the war in Sudan began in mid-April 2023, people – many of them South Sudanese returnees – have streamed across the frontier from the north.

Both governments have been reluctant to invest in this disputed region, which is consequently very poor, and deprived of essential infrastructure for health – not one of REACH’s target locations in Abyei had a functional refrigerator in which vaccines could be stored when the project began.

Lack of cooling facilities is a decisive hurdle for any vaccination programme, but for this one it was probably one of the more straightforward problems to fix. REACH partners and local health authorities got hold of Arktek devices – chunky teal dumbbell-shaped vaccine storage containers, each capable of keeping more than five litres’ worth of vaccines cool for a month without being plugged into an energy source – from UNICEF’s Vaccine Supply Division in Copenhagen.

Navigating the conflict took careful coordination with local security organs and the UN Interim Security Force for Abyei. It also took a knack for timing. Even amid persistent insecurity, there are periods of relative calm. Over the months, REACH partners have been able to make it into locations that had been previously inaccessible because of intercommunal skirmishes, or road ambushes and looting.

Reaching communities has been dependent on community trust and buy-in. REACH teams – staffed by local partners with indispensable local knowledge – worked together with community leaders to pinpoint obstacles, track progress, and share information. To communicate with the people at large, vaccination teams used mobile public address systems that played educational jingles and radio-style dramas – actual radio stations do not make it to these frontier zones – that touted the importance of immunising zero-dose children.

And finally, the vaccinators went house-to-house. The health workers who knocked on Achok Ajak’s door in April had been dispatched by the humanitarian agency GOAL, one of REACH’s partners in South Sudan. Said Ajak, “I encourage GOAL to continue with this approach of vaccinating our children. Many children in my community did not receive their scheduled vaccine doses due to insecurity and displacement. I am happy that my child is now fully immunised and protected from preventable diseases.” 

• By Chantal McGill ,  Onyango Okech ,  Kon Thon Miyen ,  George Njenga, Gavi