By Madeline Holcombe, CNN
(CNN) — Foodborne illnesses aren’t just a nuisance after a questionable meal; they are a significant cause of death and severe disease.
An estimated 1.5 million deaths were caused by foodborne illnesses worldwide in 2021, according to a study published Wednesday in the Lancet.
“It is imperative that countries implement strategies to improve food safety to reduce this substantial burden of disease arising from contaminated food,” the study said.
While the number is distressing, it isn’t surprising to experts, said Dr. Harris Wang, chair and professor of the department of systems biology at Columbia University Irving Medical Center. He was not involved in the study.
Much of the world may be surprised by the deadliness and the burden –– meaning the deaths as well as total incidence and disability-adjusted life years, said Dr. Julie Jean, professor in the department of food sciences at Université Laval in Québec, Canada. Jean, who was not involved in the study, said the impact mirrors other major infectious diseases like HIV or malaria.
The impact is often underestimated because so many cases are mild or unreported, but the data highlights that foodborne illnesses are both a major health problem and a shared, systemic problem, Jean added.
However, there are things that can be done in your home to prevent these kinds of illnesses.
Sources of foodborne sickness
People develop foodborne illnesses when their food is contaminated with a wide range of hazards, including parasites, chemicals and microorganisms, Jean said. Common examples are salmonella, E. coli, norovirus and listeria.
These pathogens can cause problems such as gastroenteritis and diarrhea but can also progress to more serious complications including sepsis and bacteremia, a condition in which bacteria enter the bloodstream, Wang said.
For some foodborne illnesses, the problem comes from temperature regulation issues –– food is either undercooked or left at temperatures that are too warm, which encourages bacteria to grow, Wang said. Other times, the issue comes from improper hygiene in food handling, which allows viruses to spread, Jean added.
Foodborne sickness prevention and treatment is uneven globally, and low- and middle-income countries are especially at risk for deaths and severe infections, Jean said. Variations in food safety systems and regulations, as well as access to health care influence how prevalent these illnesses are in different countries, she said.
Who is at risk of these illnesses
Risk can also vary from person to person. “Young children with less developed immune systems, the elderly with decreased immunity, or immune-compromised individuals tend to be particularly susceptible to food borne illnesses,” Wang said. Pregnancy, which can impact a body’s immune system, puts people at an increased vulnerability to severe foodborne illness, Jean added.
Disturbances in the gut microbiome, which can result from the use of certain medications or antibiotics, make someone more susceptible to that pathogens from food that can cause disease, Wang said.
Signs of foodborne illness may include nausea, vomiting, diarrhea, abdominal cramps and fever, according to Tufts University School of Medicine. Typically, symptoms resolve within two to seven days, but people with severe symptoms, including diarrhea that lasts more than three days, high fever and blood in stool should seek medical attention.
For people who do develop foodborne illness, hydration is key, Wang said.
“Dehydration will result in progressively worse symptoms and resu