and regional surveillance and outbreak reporting systems, continues to impede the development of evidence-based food safety interventions in many WHO member countries (WHO, 2002a, 2004). For example, the EU has undertaken a fully harmonized baseline surveillance study for Salmonella in poultry production which is the basis of targeted interventions to manage the prevalence of this foodborne pathogen (EFSA, 2006a).

     Epidemiological uncertainty about the origin, prevalence and severity of much foodborne illness makes it difficult to target resources and do comprehensive and proactive food safety control planning. More than 200 known diseases are transmitted by food, however underreporting, illnesses caused by unknown pathogens and other factors, such as water sanitation, obscure the origin of foodborne illness. The confluence of these factors impedes estimates to characterize the burden of existing foodborne illness, much less the evolution of future pathogens.

     Pathogens featured in today's headlines, such as Listeria monocytogenes or E. coli O157:H7, were not identified as major causes of foodborne illness 20 years ago (Mead et al., 1999). However, for most foodborne infections effective preventive interventions can be taken despite a lack of exact epidemiological knowledge. Furthermore, the majority of foodborne infections in most countries are caused by a few pathogens e.g., in the EU, Salmonella and Campylobacter accounted for about 96% of reported zoonoses cases in 2005 (EFSA, 2006a). In developing countries, actions such as water sanitation and heat treatment of food in combination with measures for basic sanitary and hygienic routines would have significant health benefits, even without immediate support of detailed surveillance data. Diarrhea is the leading causes of illness and death in less developed countries, killing an estimated 1.9 million people annually worldwide and almost all deaths are caused by food or waterborne microbial pathogens (Schlundt et al., 2004). This incidence of morbidity and mortality is consequent to the fact that globally > 1 billon people, and in sub-Saharan Africa > 40%, lack access to clean drinkable water and 2.4 billion do not have basic sanitation (CA, 2007). In practice, this means that these people have to drink water with fecal contamination from humans and animals and their intestinally excreted pathogens.

      For countries with weak surveillance and outbreak detection systems, estimating the burden of foodborne illness is even a more daunting challenge, despite the assistance provided by WHO's Global Salm-Serv, Global Outbreak and Response Network (GOARN), International Food Safety Authorities Network (INFOSAN) and the FAO/OIE/WHO Global Early Warning System and Response for zoonotic disease surveillance (Flint et al., 2005). Further complicating the future of foodborne disease surveillance is the likelihood that as a result of climate change, new pathogens will emerge, particularly in fish and shellfish raised in water whose quality is degraded or contaminated (Rose et al., 2001).

     The timeliness and efficacy of preventive or prophylactic food safety interventions depend on accurate, comprehensive and timely surveillance information. The factors of uncertainty in calculating the burden of foodborne illness are compounded by weak national surveillance systems

upon which the international systems depend. Many governments, particularly in least developed countries, are unable to finance the development of such surveillance systems as part of national health system planning.

     Since welfare benefits from agricultural trade are expected to increase for only a few developing countries as a result of the WTO Doha Round of negotiations (Bouet et al., 2004; Anderson and Martin, 2005; Polaski, 2006), it is unlikely that non-benefiting countries will be able to pay the costs of foodborne disease surveillance systems and SPS interventions from trade revenues. Therefore, in what follows we assume that some form of public finance and donor assistance will be required for capacity building in surveillance and other food safety activities. Furthermore, public finance may be involved in helping to insure against global foodborne illnesses risks that are not and perhaps cannot be insured by private firms.

7.3.1.2 Financing a public good

The globalization of the food and feed trade enables a broader and more rapid transmission of foodborne illness, particularly from high-risk microbial pathogens of animal origin (OIE, 2006). Development of surveillance data often becomes a priority only if a food contamination incident or zoonosis threatens trade, e.g., BSE and avian influenza. Such threats to trade usually focus only on emerging diseases and less on those that are prevalent and perennially cause major problems. Yet the costs of foodborne illness far exceed those that can be recovered from inspection fees or other forms of trade related SPS financing, even when the origin of an illness can be traced back to a specific source. Whereas the costs of food safety measures can be internalized to some extent in the cost of a product, there is no adequate mechanism for financing the public health costs resulting from transborder foodborne illness. FAO and WHO recognize that "[f]ood safety is an essential public health issue for all countries," but the normative framework and technical assistance planning for food safety in developing countries is largely a function of trade policy, or more broadly of the economics of private markets. Donor interest in and exporting country demand for SPS related assistance tends to be triggered by the threat of trade disruption or to ensure that food imports are safe (World Bank, 2005).

     Although food safety is characterized as a global public good, economic analysis of food safety interventions often is framed largely in cost/benefit terms of market failures, in this case, the failure to internalize such negative cross border externalities as foodborne illness. Attempts to mitigate these externalities on an ad hoc emergency basis "is a costly and unsustainable form of assistance" (World Bank, 2005). The role of public food safety management is defined in terms of serving the market, without, however, an adequate financing mechanism designed to enable the development of food safety as a public good and taking into consideration the full and considerable cost for foodborne infection e.g., loss of labor time and cost for medical care. New proposed public finance mechanism (e.g., Kaul and Conceição, 2006) could be adapted to the provision of food safety, both on a global and regional basis, as a global public good. A World Bank study has argued cogently for a more proactive and preventative supply and demand approach to providing