Time to count the burden of foodborne disease
Many people suffer or die from foodborne disease each year — but how many? Arie Havelaar believes a WHO initiative will find out.
Foodborne disease outbreaks make the news daily. We can assume that billions of people fall ill every year, and that many die, because they ate food contaminated with bacteria, viruses, parasites or chemicals. But no-one has ever quantified the problem comprehensively. Indeed, we have only a sketchy idea of how many people suffer from foodborne diseases every year, or the economic damage they cause.
The recent reports of melamine-contaminated milk powder in China remind us that foodborne illnesses can hit at any time and anywhere. Over 50,000 children in China suffered kidney problems and four died from drinking the contaminated milk powder, which was also exported to dozens of countries. There is no telling how many more victims we will see over the coming months.
We usually associate foodborne diseases with diarrhoea or vomiting, but they cause hundreds of illnesses. Their wide spectrum encompasses well-publicised ones, such as salmonellosis, avian flu and variant Creutzfeld-Jacob-Disease, but also less well-known ones, such as contamination by aflatoxin in peanuts, pistachios and other nuts as well as milk or methylmercury in fish, which can cause neuro-developmental disorders.
The real tragedy of these diseases is played out in developing countries, where people are more exposed to hazardous environments, poor food production processes and handling, inadequate food storage and hygiene during food preparation, and poor regulatory standards.
The tropical climate of many developing countries also helps pests and naturally occurring toxins proliferate, and people in these regions are at higher risk of contracting parasitic diseases. When people are malnourished, or living with HIV/AIDS, their immune systems are less able to fight foodborne diseases. And in severe famines, there is also an understandable reluctance to discard contaminated or spoilt food.
Every year, over 2 million children die from diarrhoeal diseases, a considerable proportion of which probably came from food. But the real death toll from across the spectrum of foodborne disease, is likely to be much higher.
Beyond these health impacts, foodborne diseases also affect economic development, and particularly challenge agricultural, food and tourist industries.
Developing countries' access to food export markets depends on their ability to meet the World Trade Organization's regulatory requirements. Unsafe exports can cause severe economic losses. For example, in early 2008, Saudi Arabia refused Indian poultry products valued at nearly US$500,000 following a bird flu outbreak in West Bengal.
Developing countries need to make significant investments in food safety prevention and control efforts, and the international community also needs to help.
A first step must be accurately assessing the number of people affected world-wide. But given the complexity and variety of diseases transmitted through food, and the paucity of data available at a country level, no public health agency has so far dared to tackle this herculean task.
While some international efforts are underway to estimate the burden of specific foodborne illnesses, such as the International Collaboration on Enteric Burden of Illness Studies, the complete picture of all relevant diseases remains unfinished.
In 2007, the WHO launched an international initiative to fill in the gaps. The WHO Initiative to Estimate the Global Burden of Foodborne Diseases aims to quantify how many people die from or are affected by all major foodborne causes each year. It hopes to report by 2011. The initiative operates through an expert group, the Foodborne Disease Burden Epidemiology Reference Group (FERG), that includes scientists from all regions of the world and all areas of food safety, as well as professionals from policy and regulatory bodies.
Global atlas of disease
FERG plans to collect and summarise existing scientific data on foodborne disease and mortality into a global atlas. It will also train people from developing countries and help them conduct their own national studies to estimate and monitor the burden of disease from unsafe food.
The group invites stakeholders from governmental and non-governmental organisations, industry, consumer groups, donors and scientific media to get involved, open new communication channels and explore how the initiative can best achieve its aims.
The WHO will welcome involvement in this effort to count the millions affected by these entirely preventable diseases. Could you help provide the much-needed epidemiological yard-stick of death and disability against which progress can be measured?
The next FERG stakeholder meeting is scheduled for 20 November, in Geneva, Switzerland. If you are a professional working with development issues, you should have it in your calendar.
Arie Havelaar is chair of the WHO's Foodborne Disease Burden Epidemiology Reference Group.