One out of every 10 people worldwide suffer from foodborne diseases annually, and children and the poor suffer most, reveal findings of a World Health Organization task force headed by a University of Florida senior researcher.
The announcement, made Wednesday, comes after more than eight years of research and data analysis by a WHO task force composed to measure the effect of foodborne diseases on populations around the globe.
"The groups most adversely affected by the foodborne diseases are children and people in low-income regions of the world," said task-force leader Dr. Arie Havelaar with UF's Emerging Pathogens Institute. "Of those who lost years to ill-health, disability or early death, 40 percent were children under 5 years old, even though they constitute only 9 percent of the world population. Foodborne illnesses affect people on the African continent the most, followed by sub-regions of Southeast Asia and the eastern Mediterranean."
"Estimating the burden of foodborne diseases is highly complex due to the many diseases involved," Havelaar said. "The full extent of chemical and biological contamination of food, and its burden to society, is still unknown."
The WHO created the Foodborne Disease Burden Epidemiology Reference Group in 2007 to study global variation in the impact of foodborne disease. After considering the known disease-causing agents that can be transmitted by food, the group identified 31 hazards as the most necessary to include.
The group found that these 31 foodborne hazards caused 600 million foodborne illnesses and 420,000 deaths in 2010. Results from the study indicate that up to 33 million healthy life years are lost each year due to foodborne diseases each year -- a number on par with the "big three" infectious diseases -- HIV/AIDS, malaria and tuberculosis -- and air pollution, but clearly lower than the burden of dietary risk factors or unimproved water and sanitation.
Diarrheal disease agents were the most frequent causes of foodborne illness - particularly norovirus and Campylobacter spp. Non-typhoidal Salmonella enterica, also a diarrheal disease agent, is capable of causing blood poisoning in people with weakened immune systems and was a major cause of death among the pathogens chosen for the study.
Other major pathogens causing foodborne disease deaths included Salmonella Typhi, a subspecies of Salmonella enterica; Taenia solium, a tapeworm that comes from pork products; and the hepatitis A virus.
Dr. Brecht Devleesschauwer, an assistant scientist at UF's department of animal sciences, worked with Havelaar to analyze data from the study.
"We compiled information from a variety of data sources, including national surveillance systems and scientific literature, and used expert opinion and statistical modeling to fill data gaps," Devleesschauwer explained. "In addition to disease incidence and deaths, we also quantified the disease burden in terms of Disability-Adjusted Life Years -- the number of healthy years of life lost due to illness and death -- to facilitate ranking between causes of disease and across regions."
Dr. Kazuaki Miyagishima, the director of the Department of Food Safety and Zoonoses at the WHO, gave his support to the group's analyses in a WHO statement.
"This report," he said, "should enable governments and other stakeholders to draw public attention to this often under-estimated problem and mobilize political will and resources to combat foodborne diseases."