Child wasting in Gaza tracked aid access, three times in 19 months

A surveillance study published in The Lancet on 8 October reports 265,974 mid-upper arm circumference measurements taken from 219,783 uniquely identified children aged 6 to 59 months across the Gaza Strip between 1 January 2024 and 15 August 2025 [s1]. It is one of the largest nutrition datasets assembled inside an active conflict, and its value lies less in any single prevalence figure than in the shape of the curve it produces.

What was measured, and how

Screening took place at 16 UN Relief and Works Agency for Palestine Refugees in the Near East health centres and 78 medical points established inside school shelters and tent encampments across Gaza's five governorates [s1]. Children were screened by mid-upper arm circumference, a tape measurement of the upper arm; those with a MUAC under 125 mm were enrolled into therapeutic feeding [s1].

The authors converted raw measurements into MUAC Z scores using published WHO age-specific and sex-specific arm circumference growth curves, then reported monthly prevalence of acute wasting (Z score below -2) and severe wasting (Z score below -3) [s1]. UNRWA funded the study [s1].

Two-thirds of children screened were in Khan Younis and the Middle Governorates [s1]. That is a sampling reality, not a random sample of Gaza's children, and it is the study's most important limitation: this is surveillance data from where screening was possible, in a population that was repeatedly displaced.

The curve

Between January and June 2024, monthly acute wasting prevalence ranged from 5 percent (34 of 722 children screened) to 7 percent (794 of 10,907) [s1].

After approximately four months of severe aid restrictions running from September 2024 to mid-January 2025, prevalence rose from 8.8 percent (1,601 of 18,225 children) to 14.3 percent (1,661 of 11,619) [s1]. The highest figures within that period were in Rafah, at 32.2 percent (95 of 295 children screened), and among children aged 24 to 59 months, at 21.0 percent (1,366 of 6,518) [s1].

Then a six-week ceasefire, marked by a substantial increase in aid trucks entering through territory borders, and by March 2025 wasting prevalence had fallen to 5.5 percent (831 of 15,165) [s1].

Then an 11-week blockade from March to May 2025 and continued severely restricted entry of food, water, medicines and fuel afterwards. By early August 2025, 15.8 percent of screened children (1,213 of 7,668) were acutely wasted, including 3.7 percent (280 of 7,668) severely wasted [s1]. The authors estimate that corresponds to more than 54,600 children in need of therapeutic care [s1].

Why the shape matters more than the level

Prevalence estimates from convenience screening in a displaced population are hard to interpret in absolute terms. Families with visibly unwell children are more likely to present; the composition of who is screened changes month to month as people move.

The three-phase pattern is more robust than any one number, because the same measurement method in the same facility network produced a fall and then a rise. Wasting went up under restriction, down during a period of increased aid entry, and up again under renewed blockade. That is close to a natural experiment, and it identifies the binding constraint as aid access rather than any slower underlying process.

The 5.5 percent figure recorded in March 2025 is the most informative single data point in the series. It shows that the March-to-May deterioration started from a low base — the population's nutritional status was recoverable, and had recovered, within weeks of supplies entering.

What MUAC does and does not capture

MUAC is used in emergencies because it is fast, needs no scales, and predicts mortality risk well in young children. It is not a complete measure of malnutrition. It does not capture stunting, which reflects chronic deprivation over years, and it can miss some children who would be classified as wasted by weight-for-height. A MUAC-based prevalence and a weight-for-height prevalence in the same population are not interchangeable numbers.

The study's own framing is that after nearly two years of war and severe restrictions on humanitarian aid, tens of thousands of preschool-aged children are experiencing preventable acute malnutrition and facing increased mortality risk [s1]. Acute wasting raises the risk of death from common childhood infections; it is not itself a count of deaths, and this study did not measure mortality.

The accompanying comment

The Lancet published the study alongside a commentary titled "Documenting atrocity: child malnutrition in Gaza" [s2]. The pairing is itself part of the record — the journal chose to frame the dataset as documentation rather than as a routine nutrition survey.

What to watch

The operational question the data raise is whether therapeutic feeding capacity can absorb the caseload the August figures imply, and that depends on the same supply corridors whose closure produced the caseload. The measurement question is whether screening coverage holds: the number of children screened in the August window, 7,668, is well below the 18,225 screened at the start of the 2024-25 restriction period [s1]. A falling denominator in a surveillance system is its own signal, and it makes each subsequent prevalence estimate harder to compare with the ones before it.

Sources

• Assessment of malnutrition in preschool-aged children by mid-upper arm circumference in the Gaza Strip (January, 2024–August, 2025) — The Lancet, 8 October 2025
• Documenting atrocity: child malnutrition in Gaza — The Lancet, 8 October 2025