A World Health Organization (WHO) spokeswoman warned on Tuesday that if the Gaza Strip’s health system is not fixed, more people there may perish from illness than from bombardment.

Around 40% of the almost 15,000 verified deaths from Israel’s shelling of Gaza are believed to have been children, according to Gaza health officials recognized as credible by the UN. Many more deaths are thought to have been lost under debris.

Israel has sworn to annihilate Hamas, the militant group that rules Gaza, after its gunmen burst across the fence and killed around 1,200 people and seized 240 captives on October 7.

“Eventually we will see more people dying from disease than we are even seeing from the bombardment if we are not able to put back [together] this health system,” said the WHO’s Margaret Harris at a UN briefing in Geneva.

She repeated concerns about a rise in outbreaks of infectious diseases, particularly diarrheal diseases.

Citing a UN report on the living conditions of displaced residents in northern Gaza, she said: “[There are] no medicines, no vaccination activities, no access to safe water and hygiene and no food. We saw a very high number of cases of diarrhea among infants,” she said.

She described the collapse of Al-Shifa Hospital in northern Gaza as a “tragedy” and voiced concern about the detention of some of its medical staff by Israeli forces during a WHO evacuation convoy.

James Elder, a spokesperson from the UN Children’s Agency in Gaza, told reporters by videolink that hospitals in Gaza were full of children with war wounds and gastroenteritis from drinking dirty water.

“I met a lot of parents… They know exactly what their children need. They don’t have access to safe water and it’s crippling them,” he said.