Researchers have assessed the likely toll of Israel’s military campaign, including vast indirect casualties. Illustration : Mona Chalabi/The Guardian

Even if Israel’s bombing campaign were to stop, the death toll in Gaza is expected to soar. A letter published in the medical journal the Lancet claims that the final figure could eventually be about 186,000. Written by scientists who model how war affects health, the letter lays out the importance of an accurate count – and the difficulty of achieving one.

For the past nine months, Israeli forces have waged an intense military campaign that has killed about 38,000 people in Gaza, according to Gaza’s health ministry. Over time these numbers (acknowledged by the United Nations, the World Health Organization and Israeli intelligence services) have become more difficult to assess, with officials less able to keep pace with the killings. An additional 10,000 people are believed to be buried under the rubble in Gaza. They have not been counted among the dead.

If a permanent ceasefire were declared today, you might think the death toll would stop there. But warfare doesn’t just kill people through direct violence. In recent years, epidemiologists who study the spread of disease during armed conflict have begun to count what they call the indirect casualties of war. These deaths are caused by factors such as malnutrition, lack of medication, and unsanitary living conditions – the reverberations of warfare, which follow inevitably and predictably from it.

The number of indirect casualties often vastly exceeds direct ones. In East Timor, about 19,000 people were either killed or disappeared between 1974 and 1999, most of them during an Indonesian invasion and occupation that some scholars have called a genocide. But that count doesn’t come close to capturing the full human cost : an estimated 84,000 additional people eventually died after an Indonesian campaign of mass displacement and starvation. That’s four indirect deaths for every direct death.

This article was amended on 12 July 2024 to refer to the ICJ finding there was a “risk” of genocide in Gaza.</p

I spoke to two co-authors of the Lancet letter, Salim Yusuf and Rasha Khatib, about the eventual death toll in Gaza.

Yusuf, the director of the Population Health Research Institute at McMaster University in Canada, said that early in the conflict, he considered four to one a baseline ratio for Gaza, based on data from previous conflicts : at a minimum, he expected four indirect deaths for every direct death. But now he was worried that the final total could be much higher.

In the most recent draft of their analysis, Yusuf and his colleagues found the four-to-one ratio could mean 186,000 total deaths in Gaza. These numbers represent a staggering 8% of Gaza’s 2.4 million people.

Khatib, the lead author of the letter and a clinical epidemiologist at Advocate Aurora Research Institute in Wisconsin, told me that these figures should be treated as very rough estimates, not hard predictions. “As healthcare systems collapse, information systems collapse too,” she said. “Direct death figures are going to become less reliable as time goes on, and that’s the most important number to make these projections.”

This has already happened. The damage to infrastructure, including hospitals and mortuaries, has meant that Gaza’s health ministry has been obliged to add unidentified bodies to its previously published list of names (the unidentified make up 30% of the total count).

Accurate death counts are essential. For accountability to happen, the true cost of war must be understood. And recovery, if there is to be any, requires accurate death counts in order to assess infrastructure and aid needs. What’s more, the dead deserve to be counted. At a minimum, the bereaved hope that their loved ones will be counted among the dead and help to persuade those with power to prevent future casualties. The concept of a martyr or “shahid” to the Palestinian cause has existed since the Israeli occupation first began.

For now, though, “the precision of these numbers is not as important as their magnitude,” Yusuf said. Even if the team’s calculations include a large margin of error, the final death toll still probably won’t be measured in tens of thousands – it is likely to be measured in hundreds of thousands.

Illustration : Mona Chalabi/The Guardian

There are many reasons why conflicts kill so many people indirectly. For one, damage to healthcare infrastructure matters. When there aren’t enough doctors, hospital beds, medical supplies, or functioning diagnostic laboratories, Khatib explained, the probability of death increases not just for people who are injured by bombs or bullets, but also for those who are pregnant, or disabled, or who just happen to have had an ill-timed heart attack.

Gaza had much stronger healthcare infrastructure (in terms of vaccination rates and access to sanitation) than East Timor. But the healthcare system was under strain long before the latest military escalation. According to an April 2023 report from the Israeli human rights group B’Tselem, a more than 15-year blockade maintained by Israel led to “a constant shortage of medicines and medical equipment”. As of mid-June, only 17 of Gaza’s 36 hospitals were partially functioning, and the rest were entirely destroyed.

More than 80,000 Palestinians have been injured in the war, according to Gaza’s health ministry. “I had many, many pediatric patients who were war-wounded, burned orphans, traumatic amputations, and that is something different than what I witnessed in Iraq, or elsewhere,” Seema Jelani, a pediatrician who worked in Gaza’s Al-Aqsa hospital in December, recently told the New Yorker. “Within the two weeks that I was there, I saw it go from a semi-functional hospital to a barely or non-functional hospital as a result of increasing violence in surrounding areas.”

To live and to heal, you also need access to food and clean water. Between 1999 and 2005 during the war in South Sudan, government forces and militias looted food supplies ; severe shortages contributed to an indirect-to-direct death ratio of about nine to one, according to a Geneva Declaration report. In Gaza, Israeli forces have destroyed farms that once grew citrus fruits, olives, grapes, dates and watermelons. They have also halted trucks full of humanitarian supplies at the border. Meanwhile, many countries, including the US and much of Europe, are currently withholding funding from the United Nations Relief and Works Agency for Palestine Refugees in the Near East, because of Israeli allegations that some Unrwa employees were linked to the 7 October attacks in Israel. “Food insecurity means that people have to travel and wait in line for food and water,” Khatib said. “They’re standing in cold weather in crowded spaces.” More than 90% of Gaza’s population was facing crisis levels of hunger in December, according to the World Health Organization, and clean water is scarce.

A third key factor is displacement. When people are forced to leave their homes, there is not just emotional trauma – displaced people suffer from elevated rates of PTSD and suicide – but physical consequences. In overcrowded, unsanitary camps, infectious disease spreads fast. In Sierra Leone, where almost half of the population was displaced during the country’s 11-year war, the indirect-to-direct death ratio was a staggering 16 to one.

Even before the war, most of Gaza’s inhabitants were refugees. In December, Unrwa reported that at least 1.9 million people – nearly 80% of the population – had fled their homes, many of them in response to Israeli warnings to move or risk death. Because Gaza’s only available exit, the Rafah border crossing with Egypt, remains severely restricted, the population of Rafah rose from about a quarter million to more than a million. Consequently, about half of Gaza’s population was concentrated on just 17% of its land. According to the World Health Organization, diseases that spread in close quarters are “thriving” : doctors have observed “numerous cases” of meningitis, skin rashes, scabies, lice and chickenpox. In May, Israeli forces escalated attacks on Rafah, causing half of Gaza’s population to be displaced yet again.

Khatib fears that the war in Gaza could have the highest indirect death rate of any conflict in recent history and the figures published in the Lancet letter are “conservative”. “There will be more loss around everyone,” she said. “The recovery, mental and physical, the rebuilding of infrastructure – all of it becomes harder for those who are left.”

Illustration : Mona Chalabi/The Guardian

At the start of the Covid-19 pandemic, public health authorities warned that if the novel coronavirus spread unchecked, it could kill millions of people. To contain it, they recommended interventions such as lockdowns, masking, testing and the rapid development of vaccines. These measures slowed the spread of the virus and changed the course of the pandemic.

Lifesaving interventions are possible in Gaza, too. The Israeli government has the power to limit the casualties – not just the number of direct deaths now, but also the much larger number of indirect deaths in the future. Israeli forces can do much more to spare crucial infrastructure such as hospitals, refugee camps, and schools. Israel can lift restrictions on aid and imports, allowing more food, fuel, clean water and medical supplies, to enter Gaza. These resources would not only help the injured, but also those with cancer, diabetes or short-term illnesses. They could also reduce the harms of displacement by allowing Palestinians to safely return to what is left of their neighborhoods, and to rebuild. Most significantly, of course, Israel could stop its military assault on Gaza.

Without drastic change, Israel will further support claims in the international court of justice that it is committing genocide. Genocidal acts include inflicting “conditions of life” that are intended to bring about the destruction of a group – in other words, indirect deaths must be considered, too. South Africa listed many of these conditions when it made its case against Israel at the ICJ, which ruled there was a plausible risk of genocide.

It might be years before researchers establish a precise death toll in Gaza but what’s clear is that the continuing campaign of direct and indirect violence will have a toll far beyond the immediate catastrophe.

Mona Chalabi