The World Health Organisation (WHO) has released its first ever global estimates of foodborne diseases, with findings indicating that children under five account for almost one-third of all deaths.
The report estimates that foodborne diseases are caused by 31 agents including bacteria, viruses, parasites, toxins and chemicals, of which as many as 600 million, or almost one in 10 people in the world, fall ill after consuming contaminated food. Of these, 420,000 people die, including 125,000 children under the age of five years.
While African and south east Asian regions have the highest incidence of foodborne illnesses, WHO states that certain diseases, such as those caused by non-typhoidal Salmonella, are a public health concern across all regions of the world, in high- and low-income countries alike.
Other diseases, such as typhoid fever, foodborne cholera, and those caused by pathogenic E. coli, are much more common to low-income countries, while Campylobacter is an important pathogen in high-income countries.
“Until now, estimates of foodborne diseases were vague and imprecise. This concealed the true human costs of contaminated food. This report sets the record straight,” says Dr Margaret Chan, director general of WHO.
“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.”
Key foodborne diseases and hazards as listed by WHO:
Bacteria:
• Listeria can result in blood poisoning and meningitis, and is usually spread by consuming contaminated raw vegetables, ready-to-eat meals, processed meats, smoked fish or soft cheeses.
• Brucella, commonly from unpasteurised milk or cheese of infected goats or sheep, can cause fever, muscle pain or more severe arthritis, chronic fatigue, neurologic symptoms and depression.
• Cholera can be caused by consuming food contaminated with Vibrio cholerae. It causes watery diarrhoea that can be fatal within hours if left untreated.
Virus:
• Hepatitis A is a liver disease caused by the hepatitis A virus, transmitted through food contaminated by the faeces of an infected person. It causes jaundice, nausea, fever, malaise and abdominal pain.
Parasites:
• Toxoplasmosis, caused by Toxoplasma gondi, spread through undercooked or raw meat and fresh produce, can result in impaired vision and neurological conditions.
• Pork tapeworm (Taenia solium) can cause cysts to develop in the brain (cysticercosis), which is the most frequent preventable cause of epilepsy worldwide.
• Echinococcus tapeworms can infect humans through food contaminated with dog or fox faeces. They can cause tumours to form in the liver, lungs and brain.
• Chinese liver fluke (Clonorchis sinensis) commonly contracted through raw and incorrectly processed or cooked fish, can cause bile duct inflammation and cancer.
Chemicals and toxins:
• Aflatoxin is a toxin produced by mould that grows on grain that has been stored inappropriately, and can cause liver cancer, one of the most deadly forms of cancer.
• Cyanide poisoning occurs when inappropriately processed cassava is consumed.