The world has made great progress against malaria in the last decade, but the fight is stalling for lack of funds, the World Health Organization’s annual report on malaria concluded on Monday. The amount spent on the disease by all countries rose to $1.8 billion last year, compared with $100 million in 2000, and, as a result, about one million children’s lives were probably spared over that time, the report said. But it would take $5 billion a year to get nets, insecticide spraying, diagnostic kits, effective drugs and hospital treatment to everyone needing them, and donor contributions, especially to the Global Fund to Fight AIDS, Tuberculosis and Malaria, have been nearly flat since 2010. Last year, the number of new nets purchased fell sharply, to 66 million from 145 million two years ago. Since nets wear out in three years and children are always being born, large numbers of infants and toddlers will soon be unprotected if more money does not come in, the report warned. The W.H.O. estimated that there were 219 million malaria cases in the world in 2010, with 660,00 deaths.