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This week the World Health Organisation (WHO) released the most comprehensive report to date on the state of foodborne illness worldwide; one of the key papers presenting the data and results that contributed to the report has just been published in F1000Research.

The WHO report, titled ‘Estimates of the Global Burden of Foodborne Diseases’, presents global estimates of the burden of disease for 31 bacteria, viruses, parasites, toxins, and chemicals that can contaminate food.  The initiative, undertaken by the WHO Foodborne Disease Burden Epidemiology Reference Group (FERG), represents a continuing effort to address the lack of data on foodborne illness and develop a global strategy to improve food safety.  The new data provide evidence that show almost 1 in 10 people fall ill every year from eating contaminated food, resulting in 420, 000 deaths.

The FERG Task Forces report their research in a series of 6 papers published in various journals today. In a translational research paper,  just published in F1000Research and now awaiting formal peer review, Gibb et al. of the FERG Task Force on Chemicals in Food used global estimates of incidence to calculate illnesses, deaths and ‘disability adjusted life years’ (DALYs) for dioxin, aflatoxin, peanut allergen, and cyanide present in cassava.

Cassava, also known as yucca or manioc, is a major staple food in the developing world due to its draught tolerance and high carbohydrate content.  It is also a natural source of the toxicant cyanide and, as a result, a causative agent for konzo (a paralytic disease associated with cassava consumption, particularly in times of famine).  Gibb et al. used data on the incidence of konzo from six African countries to estimate the burden of cyanide in cassava.

Likewise, prevalence data on peanut allergen as well as aflatoxins and liver cancer were used to estimate global burden. All allergen cases are assumed to be the result of consuming peanut or peanut-containing products, and aflatoxin exposure is believed to be entirely from food consumption.

Gibb et al. also capitalised on data collected by national authorities to monitor dioxin in the food supply and breast milk.  A comparison of breast milk concentrations from 50 countries provided country-specific estimates of the incidence of dioxin induced hypothyroidism and decreased sperm count.

The results underscore the global threats posed by chemicals in food: together, the four selected chemicals were estimated to be associated with 339,000 illnesses, 20,000 deaths, and 1,012,000 DALYs in 2010 (DALYs are the most common single metric used for death and disability, and are expressed as the sum of years lived with disability and years of life lost; one DALY equates to one year of healthy life lost). Aflatoxin was associated with the highest global DALY (636,869), whereas dioxin was associated with the greatest number of illnesses (193,447, albeit 0 deaths).

DALYs were also calculated by global region (where data for a region did not exist, the gaps were filled through extrapolation). The Southeast Asian, Western Pacific, and African regions showed the highest burdens, with aflatoxin making the largest contribution to burden in the latter two regions.  In Southeast Asia, on the other hand, dioxin is the largest contributor to burden. The findings also show that cyanide in cassava and aflatoxin are associated with diseases that have high case-fatality rates.  For example, the konzo case-fatality rate is approximately 21%. These rates serve as a measure of disease severity, and present the proportion of cases of a disease that are fatal within a specified time frame.

Herman Gibb, lead author of the F1000Research paper and chair of the FERG Task Force on Chemicals in Food, stresses the urgency of this effort:

“The burden of disease associated with foodborne chemicals is a critical public health issue and assessment of this issue is urgently needed.

The research presented here has important global health implications, and it is therefore important that the results be communicated quickly. The F1000Research publishing model gave us that opportunity.  Furthermore we are delighted by the transparency of the peer review process which will benefit both the readers and the authors.”

Despite the wide spectrum of illnesses described in both the F1000Research paper and the larger WHO report, an emerging theme from these analyses is evident: food safety is multisectoral and multidisciplinary.  This is emphasised by the FERG whose members include international experts from governmental departments, academia, and industry representing disciplines ranging from public health, food science, agriculture, risk assessment and clinical medicine. Similarly, the authors of the paper published today on F1000Research represent an international collaboration involving 18 affiliations and spanning 8 countries.