Diphtheria, a once vanquished killer of children, is resurgent

By Stephanie Nolen

MOGADISHU — Qurraisha Mukhtar’s two youngest children fell sick in early September, with a fever, cough and short gasping breaths. Their throats turned white, their necks swelled. She asked a healer in the neighbourhood for a remedy, but 1-year-old Salman’s struggle for air grew much worse one night and he died. The next day, Hassan, 2, began to choke, and he died, too.

Mukhtar, who lives with her family in a stick-and-tin shack on the edge of Mogadishu, the capital of Somalia, could not sit and grieve, because two more of her children began to show signs of the same illness. She and her husband appealed to friends and relatives and scraped together the money to take them to a hospital in a three-wheeled taxi.

At Demartino Hospital in the centre of the city, she was directed to a new building erected during the first year of the COVID-19 pandemic. These days, it has been repurposed to respond to an old foe: diphtheria, a horrific and vaccine-preventable disease, which is infecting thousands of children and some adults, too.

Diphtheria is caused by a bacteria that produces a powerful toxin that kills cells, usually in the throat and tonsils, creating a thick, grey membrane of dead tissue that can grow large enough to block the airway and cause suffocation. It is particularly dangerous in young children with small airways. If caught early, it can be treated effectively with antibiotics, but if not, cases can swiftly turn fatal.

It is among the diseases that were relics of pre-vaccine days but have resurged in recent years, with mass displacement driven by climate change and war. The disruptions in routine immunization that came with COVID and its stress on global health systems, and the rise in vaccine hesitancy, have fuelled their spread.

There are large diphtheria outbreaks now in Somalia, Sudan, Yemen and Chad — countries with civil wars or large populations of refugees where vaccination coverage is low, surveillance is weak and frail health systems leave children undiagnosed or treated too late.

Diphtheria was once a major killer of children in the United States and other industrialized countries, but cases began to drop with the introduction of a diphtheria vaccine in the 1940s, and by the 1970s, the disease had become rare. There was just one case a year reported in the United States in the two decades after 1996, and only a handful since.

The disease was vanishing from developing countries, too, at the beginning of the 21st century. But cases began to resurge about 15 years ago. Venezuela had a major outbreak, when its once-strong public health system fell apart during years of political instability. Bangladesh had one, beginning in 2017, mostly among Rohingya refugees packed into crowded camps. There have been nearly 30,000 reported cases in Nigeria in the past two years, mostly in the country’s north, where vaccination coverage is lower.

There have also been cases in Europe in recent years, usually among young people who emigrated from Syria or Afghanistan and were not immunized.

In the United States, the few cases have been associated with travellers. However American vaccination rates have declined slowly but steadily for the past five years; 92% of kindergarten students nationally had full coverage with diphtheria vaccination in the 2024-25 school year, down from 95% in 2020. Achieving broad immunity requires at least 85% coverage.

A child is typically vaccinated against diphtheria with a 5-in-1 combination vaccine given at 6, 10 and 14 weeks of age. If a child doesn’t get all three shots, protection is limited — and that’s often the problem for displaced and struggling families such as Mukhtar’s.

Katy Clark, an expert in diphtheria with Gavi, the international organization that helps low-income countries procure vaccines, said that as many as 1 in 4 children with diphtheria might die of the infection in countries where diagnostic and treatment options were limited. The fatality rate is closer to 1 in 20 in health systems with more resources, she said.

Somalia is the first country to apply to Gavi for new funding to give children diphtheria boosters — shots delivered to children in their second year of life, then between 4 and 7 years old and 9 to 15 years old — in areas where the outbreak has seemed most severe.

“We didn’t even have a diphtheria support modality, because we didn’t need one,” Clark said. “And now we have to build out a whole new process to help countries respond.”

Somalia’s current diphtheria outbreak has grown steadily since it began in 2023, with more than 2,000 cases reported across the country so far this year (although surveillance and reporting are both very weak, and Clark said this was most likely a significant undercount).

At Demartino Hospital in Mogadishu, nearly 1,000 patients have been admitted to the diphtheria ward this year, compared with 49 in 2024. Eighty per cent of them are children.

A health system already undermined by decades of civil war has been further hampered by the loss of much of the assistance that came from the US government, cut by the Trump administration. Diphtheria and other infectious diseases are surging as more children become critically malnourished amid a sharp drop in food aid.

Mukhtar and her family were displaced from Baidoa, in southern Somalia, by years of brutal drought. A family member in the city let them build their shack on his land.

She said that her 12 children had been vaccinated with at least some of their shots; she took them to health centres when they were small. But she had a lot of children to keep track of, and she cannot read, so she was not able to track their immunizations too closely.

The two children she brought to the hospital, a 3-year-old daughter and a severely malnourished 10-year-old son, recovered from their diphtheria infections. But Mukhtar incurred about $200 in costs for their tests and medications (the hospital operates on a ‘cost-recovery’ basis; Somalia’s Health Ministry provides just a fraction of the funds it needs to operate).

In the large ward at Demartino, every one of the 34 beds was full, and some held a couple of children. Dr Mohamud Omar, a paediatrician, made rounds monitoring their airways, making sure that the lumpy obstructions in their throats did not threaten their ability to breathe. He ordered supplemental oxygen for a few of them. Exhausted parents slumped at the end of the beds; many had four or five infected children to shuttle between.

Three of Amina Hassan’s children were admitted to the diphtheria ward in mid-September. The oldest and youngest of them improved after a few days, but her 4-year-old daughter still needed oxygen, and had proved to be allergic to the antibiotics that usually treat diphtheria. The hospital sometimes has access to the antitoxin that can neutralize the infection and is used in emergency treatment in high-income countries — but it often runs short, said Dr. Abdirahim Omar Amin, the hospital’s director.

Hassan said the children were not vaccinated: she wanted to have them immunized, she said, but when the oldest of her six children received the tuberculosis vaccine at birth, the injection site became infected, and after that her husband refused to allow the children to receive any shots.

She sat in a hospital bed with her 4-year-old in her lap and her 1-year-old, whose neck was still badly swollen, slumped against her back. “After this I am going to try to convince him to get them vaccinations, and I think he will agree,” she said of her husband.

Across the aisle from Hassan, Hawa Mahmoud was sitting between two beds that held three of her children. She was waiting for their father to arrive with three more, who had developed symptoms at home. The sickness has afflicted many students in her older children’s school in recent weeks, Mahmoud said. Now six of her seven children were infected; so far, the oldest had no signs, but she wasn’t optimistic. “They’re coming, one after the other,” she said.

-New York Times