Figures compiled by the Department for International Development (DfID) suggest that between 50,000 and 100,000 people, more than half of them children under five, died in the 2011 Horn of Africa crisis that affected Somalia, Ethiopia and Kenya.
The US government estimates separately that more than 29,000 children under five died in the space of 90 days from May to July last year. The accompanying destruction of livelihoods, livestock and local market systems affected 13 million people overall. Hundreds of thousands remain at continuing risk of malnutrition.
The authors of the report, published by Save the Children and Oxfam, suggest current emergency response systems, which they believe to be seriously flawed, will soon be tested again as new humanitarian crises loom in west Africa and the Sahel, where growing food shortages are reported.
"Early warning systems in the Sahel region show that overall cereal production is 25% lower than the previous year and food prices are 40% higher than the five-year average. The last food crisis in the region, in 2010, affected 10 million people," the report warns.
A recent Save the Children assessment in Niger showed families in the worst-hit areas were already struggling with a third less food, money and fuel than is necessary to survive.
The report, A Dangerous Delay, concludes that although drought sparked the east Africa crisis, human factors turned it into a disaster.
"A culture of risk aversion caused a six-month delay in the large-scale aid effort because humanitarian agencies and national governments were too slow to scale up their response to the crisis, and many donors wanted proof of a humanitarian...