Ms. Thomas, the Unicef water and hygiene specialist, said that during Somalia’s last famine, the deadliest areas were not the empty deserts where there was little food but the displaced-persons camps near urban areas where, comparatively speaking, there was plenty of food.
The reason was that the crowded camps became hotbeds of communicable diseases like cholera, a bacterial infection that can lead to very painful intestinal cramps, diarrhea, and fatal dehydration. Cholera is often caused by dirty water and spread by exposure to contaminated feces through fingers, food, and flies.
A hospital employee spraying disinfectant in a tent at a cholera treatment center. The crowded camps can become hotbeds of communicable diseases. CreditTyler Hicks/The New York Times.
Malnutrition certainly played its part; famine victims, especially children, were compromised by a lack of nutrients. They arrived in the camps from wasted areas of the interior with their immune systems already shot.
But in the end it was poor hygiene and dirty water, Ms. Thomas said, that tugged many down.
If rivers and other relatively clean water sources start drying up, as they are right now in Somalia, this sets off an interlocking cycle of death. People start to get sick at their stomachs from the slimy or cloudy water they are forced to drink. They start fleeing their villages, hoping to get help in the towns.
Camps form. But the camps do not have enough water either, and it is hard to find a latrine or enough water for people to wash their hands. Shockingly fast, the camps become disease factories.
Water, of course, is less negotiable than food. A human being can survive weeks with nothing to eat. Five days without water means death.
Different strategies are being emphasized this time around to parry the famine. One is simply giving out cash.
United Nations agencies and private aid groups in Somalia are scaling up efforts to dole out money through a new electronic card system and by mobile phone.
This allows poor people to get a monthly allowance and shop for staples like fresh vegetables, powdered milk, pasta, dates, sugar, salt and camel meat.
Cash payments are often better for the local economy than importing sacks of food, and the people get help fast.
Many more Africans may soon need it. Sweltering days and poor rains so far this year have left Burundi, Kenya, Rwanda, Uganda, Ethiopia and Tanzania parched and on the edge of a major food crisis.
At the cholera treatment center in Baidoa, which logged in more than 30 cases on a recent day, many people had little inkling of what caused cholera.
When Mr. Abdi, whose mother was nearly dead from the disease, was asked what had made his mother sick, he said the cause was simple.
It was the hot season.