Up to 600 million people in the world—one in 10—suffer a foodborne illness every year, the World Health Organization says today in the first-ever global estimate. Up to 420,000 die—and one-third of the deaths are in children younger than 5. That’s pretty significant, since kids make up less than one-tenth of the world’s population.
The numbers come from the WHO’s new report, Global Burden of Foodborne Diseases, released in Geneva today along with a raft of academic papers supporting its conclusions. It represents the global agency’s first attempt to quantify the problem of illness, death and disability caused by bacteria and viruses, toxins and chemicals, and parasites that travel on food.
“Until now, estimates of foodborne diseases were vague and imprecise. This concealed the true human costs of contaminated food,” Dr Margaret Chan, Director-General of WHO, said in a statement distributed in advance. “Knowing which foodborne pathogens are causing the biggest problems in which parts of the world can generate targeted action by the public, governments, and the food industry.”
The agency says it has worked for more than 10 years to compile the report, recruiting more than 100 academic experts from around the world. It also says its estimate of illnesses is conservative. In fact, it is much more conservative than the estimates reached a few years ago by the U.S. Centers for Disease Control and Prevention,which puts the toll of foodborne disease just in the United States at one in every six people, or 48 million every year.
The WHO says it compiled the report because foodborne diseases are misunderstood to be mild illnesses and thus low-priority problems for public health. But in fact, the agency says, they not only kill, but can also lead to lifelong health problems in survivors: delayed development in children, kidney and liver failure, and some cancers.
To put numbers to those longterm effects, the WHO calculated the burden of foodborne disease using not just counts of illnesses and deaths, but also a statistical result called a Disability-Adjusted Life-Year (DALY); that is, the number of expected healthy years lost because of a foodborne infection. The worldwide burden of DALYs in 2010 was 33 million years, the agency says, and children lost 40 percent of them.
The report examines foodborne illness in each of the six regions into which the WHO divides the world. It finds that diarrheal diseases—caused by Salmonella, E. coli and Campylobacter among other organisms and carried by contaminated water—are the greatest problem worldwide, especially among children. But beyond those pathogens, the problem of contaminated food differs by nation and income, and requires different policy responses to fix.
In Africa, 91 million people fall ill and 137,000 die each year from foodborne illness. While diarrheal diseases such as are responsible for 70 percent of that, tapeworms transmitted by pigs cause 10 percent of the illnesses, and 25 percent of the deaths come from toxins that travel on food, such as aflatoxin, produced by a fungus that grows on stored grain and legumes, and cyanide, naturally present in cassava roots (see Aflatoxin, a Silent Threat to Africa’s Food Supply) .
In the Western Pacific—China, Australia and the Pacific islands—125 million fall ill and 50,00 die from foodborne disease. Aflatoxin is the leading cause of illness, and more than 10,000 residents develop liver cancer every year from its aftereffects. The area also has the highest number of parasitic diseases, from not only pork, but also raw fish as well.
In densely populated Southeast Asia, where 150 million fall ill and 175,000 die each year, diarrheal diseases are still the major problem, but typhoid and hepatitis A are higher than anywhere else in the world. In the Eastern Mediterranean—that’s North Africa and most of the Middle East, where 100 million fall ill each year—a major problem is brucellosis, transmitted by unpasteurized milk from goats or sheep, which can cause long-lasting arthritis and fatigue.
As you might expect, Europe and the Americas suffer less from foodborne illness than developing nations—but even in the industrialized world, problems persist. In the Americas (77 million illness per year, 9,000 deaths) pork tapeworm and toxoplasmosis, both transmitted by undercooked meat, are major problems. In Europe—with 23 million illnesses, the region that suffers least from foodborne disease—toxoplasmosis is nevertheless a significant problem, and so is listeria, a slow-growing pathogen that survives refrigeration and can cause both miscarriage and meningitis.
Along with the report, the WHO created an online tool to help people better visualize the data.