Research ranks top ten foodborne bugs

Campylobacter, salmonella and Listeria are among a handful of foodborne bugs that cost the US billions of dollars a year and blight the quality of life for million of victims, according to new research.

The study from the University of Florida ranking the top ten riskiest combinations of bacteria and foods found that just 14 pathogens cause $14.1bn dollars in cost of illness and kill an estimated 1,322 people annually.

More than 90 per cent of the cost burden – some $12.7bn - is caused by just five bacteria: campylobacter ssp, salmonella, listeria monocytogenes, toxoplasma gondi and norovirus, said the group from the body’s Emerging Pathogen Institute.

The scientists also calculated the effect the pathogens have in loss of Quality Adjusted Life Years (QALY) – a measurement of health-related quality of life. They found the line up of 14 bugs cost Americans more than 61,000 QALY a year.

The two parameters included the cost of medical care and lost productivity from employee sick days, as well as the expense of serious complications or chronic disabilities that result from the acute illness.

Rankings

The team broke down the effect of the pathogens into two types; a straight analysis of the overall impact of each bacteria across all food types and estimates of the pathogens in combination with certain foods.

In the first metric, salmonella topped the league of foodborne bugs, costing more than $3bn in illness, responsible for over 19,000 hospitalizations, as well as causing in excess of one million illnesses and 378 deaths.

Toxoplasma, with 327 deaths, almost 4,500 hospitalizations and nearly $3bn in illness costs was next.

Third riskiest bug was campylobacter – the source of 76 deaths, almost 850,000 illnesses, 8,500 hospitalizations and $1.7bn in illness costs. Listeria costs $2,65bn and killed 255.

Combination

In the combination category a different picture emerged with Campylobacter and poultry found to be the riskiest mixture – costing $1.2bn, as well as causing 608,000 illnesses and 55 deaths annually.

Toxoplasmosis and pork was number two in the illness ranking, followed by Listeria in deli meats and salmonella in poultry. Listeria in dairy products ranked fifth, followed by salmonella in complex foods.

“The number of hazards and scale of the food system make for a critical challenge for consumers and government alike,” said Michael Batz, lead author of the report Ranking the Risks: The 10 Pathogen-Food Combinations with the Greatest Burden on Public Health. “Government agencies must work together to effectively target their efforts. If we don’t identify which pairs of foods and microbes present the greatest burden, we’ll waste time and resources and put even more people at risk.”

The team acknowledged there were “significant uncertainties” in its data sources and model assumptions used to obtain its estimates. They said they research should nevertheless act as “an important starting point in an ongoing process to improve our understanding of the very complex interactions among pathogens and foods in the US food system”.