Bags of subsidized food from the government arrive every five months, but they are consumed by the families within a week, according to Anailin’s mother, Maibeli Nava, and her neighbors.

Ms. Molero said Anailin’s case was one of the worst she had seen. The family often could not afford to feed her more than once a day — and sometimes only had rice or cornmeal to eat.

The child’s severe malnutrition case was complicated by a genetic neurological disease, which causes convulsions and muscular problems, and makes digestion difficult, the nurse said.

Anailin, who weighs half of what she should, is too weak to travel, Ms. Molero said. But she can be treated at home until she is strong enough to be taken to a neurologist, she added.

“My baby had deteriorated and was in a very bad state,” said her mother, Ms. Nava, who is 25. “I thought my daughter was going to die. She didn’t even give me her hand when I tried playing with her.”

The arrival of the nurse, and the food, made an immediate difference, Ms. Nava said: “Now she’s cheerful.”

Ms. Molero said her arrival prompted neighbors, among them the mothers and older people of the area, to line up outside the Navas’ house, in one of Toas’ fishing hamlets. They wanted to ask for help, she said.