Correction: An earlier version of this editorial incorrectly stated that drowning accounts for nearly 1 in 10 deaths worldwide. Drowning actually accounts for 1 in 14 injury-related deaths worldwide, the World Health Organization reported in November 2010. The version below has been corrected.

IN AN AGE of ethnic conflict, fatal disease and chronic malnutrition, it seems strange to stumble across figures such as this: 388,000 people die every year from drowning, according to the World Health Organization. To put this number in perspective, drowning accounts for nearly 1 in 14 injury-related deaths worldwide. It is the third-leading cause of unintentional death. It is also the greatest cause of injury and unintentional death among children younger than 5 in both the United States and Asia. This is a problem that traverses the developed and developing worlds.

Predictably, however, those from poorer countries are at higher risk: The rate of death by drowning in Asia is 30 times higher than in the United States. In Bangladesh, Cambodia, Vietnam and Thailand, drowning is responsible for 1 in 4 child deaths — more than the number who die from measles, polio, whooping cough, tetanus, diphtheria and tuberculosis combined.

What makes this public health crisis particularly problematic is that, unlike fatal disease and chronic malnutrition, drowning is not an issue at the forefront of humanitarian aid efforts. Drowning has gone largely unnoticed as a serious health matter because death counts, which rely primarily on hospital reports, fail to take drowning into account. Michael Linnan, technical director at the Alliance for Safe Children, told the Integrated Regional Information Networks that “the child drowning epidemic has been invisible.”

The Alliance for Safe Children and UNICEF’s Office of Research released a report in May that found that nearly all drowning-induced deaths are preventable. Instead of allowing this problem to languish unaddressed, governments should mobilize support for demonstrably effective and low-cost prevention strategies. The report emphasized the long-term value of teaching children over the age of 4 SwimSafe techniques — swimming and rescue training — a program that reduced drowning rates by 90 percent in a research program in Bangladesh. Building low-cost bridges and other barriers is also an effective way to protect unsupervised children from water hazards.

Gordon Alexander, director of UNICEF’s Office of Research, said that such “affordable interventions” could “save hundreds of thousands of children’s lives.” When the data are so clear and the solutions so straightforward, it is time to address what Mr. Alexander correctly termed this “hidden killer.”