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| Agenda Item 5 | Conference Room Document 81 |
second fao/who global forum of food safety regulators
Bangkok, Thailand, 12-14 October 2004
(Prepared by Malaysia)
Foodborne diseases have emerged as an important and growing public health problem with a significant impact on people's health in many countries. In Malaysia the incidence of food-borne diseases notified, namely cholera, typhoid, hepatitis A and dysentery have been less than 5/100,000 population, sporadic in nature with outbreaks confined to certain areas only. In the case of food poisoning, cases notified have mainly been in institutions ranging from 20 to 30/100,000 population.
The epidemiology of food-borne diseases has rapidly changed as newly recognised pathogens emerge and well recognised pathogens increase in prevalence or become associated with new food vehicles. The associated worldwide increase in the incidence of food-borne diseases could be attributed to a number of factors namely the ease of international travel and trade, globalisation of food supply, changes in food production and processing technologies, microbial adaptation and changes in human demographics and behaviour.
Concerned by the absence of reliable data and documentation on the burden of food-borne diseases and its public health importance, the 53rd World Health Assembly called for the development of a global strategy for reduction of the burden of food-borne diseases initiated through an appropriate food-borne disease surveillance mechanism. The overall objective was to provide countries concerned with the necessary data to reduce the burden of food-borne disease by improving food safety systems.
In many countries, the public health program has given high priority to the surveillance of foodborne diseases. Surveillance is essential for estimating the burden of foodborne diseases, identifying priorities and policy setting and evaluating the preventive and control strategies undertaken. It may also be useful in identifying emerging food safety issues.
The surveillance of foodborne diseases varies from country to country depending on its economic status, infrastructure, availability of resources (manpower and laboratory facilities) and technical expertise. In the year 2002, a WHO consultation on methods for food borne disease surveillance in selected sites had reviewed and grouped the existing food borne disease surveillance systems into 4 categories according to their capacity to generate information. It varied from one with no formal surveillance to that of an integrated food chain surveillance system. A country may be primarily within one category but may have surveillance elements from more than one category. Surveillance of food borne diseases may also be part of a national notifiable communicable disease system. However there is no clear 'best-method' of surveillance at the moment.
In Malaysia, the current foodborne disease surveillance data collected is mainly through physician-based surveillance and outbreak investigations as there is no mandatory requirement for notification from laboratories. Through this system, notification is received from government health facilities consisting of health centres, outpatient departments and hospitals and also from the private hospitals and general medical practitioners. The food borne diseases included in this list are cholera, typhoid and paratyphoid fevers, viral hepatitis A, food poisoning and dysentery.
The Ministry of Health, Malaysia has produced a manual on syndromic approach to infectious disease notification and laboratory investigation to strengthen surveillance and rapid response to emerging infectious diseases besides complementing the existing specific disease notification system. The notification is based on a syndrome, not on a specific disease, and the one related to food borne diseases is the “Acute Diarrhoeal Syndrome”. The Ministry of Health also conducts laboratory based surveillance of specific infectious diseases and includes food borne diseases due to Salmonella spp., Shigella spp., Salmonella typhi and Vibrio spp.. The Ministry of Health is currently preparing a proposal paper for a national surveillance centre for the active surveillance of foodborne diseases. It would provide better understanding of the causes and incidence of food borne diseases, measure the burden of disease and also evaluate the impact of control measures on these diseases in the country.
In Malaysia, advanced laboratory technology through the use of Pulse Field Gel Electrophoresis (PFGE) DNA fingerprinting and gel documentation are already available in the public health and university research laboratories. However, some of the problems and challenges associated with PFGE are the standardization of protocols, reagents, chemicals, electrophoretic conditions, cost and lack of sufficient trained personnel. The realization of a national PulseNet Malaysia will require training of personnel in the use of the standardized protocols so that DNA fingerprints are comparable between laboratories and between countries for rapid identification of clusters of food borne pathogens in case of disease outbreaks. PulseNet is not just about PFGE, but rather a communication network for personnel from the laboratories, surveillance, and epidemiological units to rapidly recognize an imminent food borne disease outbreak.
In Malaysia, the Department of Veterinary Services (DVS) conducts a national surveillance program for food borne pathogens associated with livestock products, namely Salmonella, E.coli O157, Campylobacter, Yersinia and Vancomycin-resistant Enterococci (VRE). The Epidemiology and Veterinary Medicine Division, DVS has formulated several diseases surveillance, control, monitoring and eradication programs/protocols of livestock /zoonotic diseases such as for Salmonella, Avian Influenza, VRE, Brucella, Tuberculosis, Johne's Disease, Nipah Virus and Bovine Spongiform Encephalopathy (BSE).
Besides disease control, eradication and disease free zone programs/protocols, a Livestock Farm Accreditation Scheme has also been implemented. The criteria of the scheme includes an infrastructure protocol, biosecurity protocol, Flock/ Herd Health Program, Good Animal Husbandry Practices, control of drug usage, labeling and trace back system and quality system. The implementation of the scheme will ensure a safe food supply.
Sources of surveillance data for food borne diseases include disease notifications, laboratory reports, environmental indices (food establishment inspection sources; agriculture, veterinary and food analyses), outbreak investigation reports, research studies, morbidity reports, case investigations, sentinel reports, surveys, census and media reports. A considerable amount of information on causative agents, disease characteristics and vehicles of transmission collected by several agencies could be successfully used to reduce the incidence of food borne diseases.
Malaysia has also actively participated in some of the activities of the WHO Global Salm-Surv network that was initiated to enhance the capacity and quality of salmonella isolation, identification, serotyping and antimicrobial resistance testing throughout the world. The Disease Control Division and Institute of Medical Research (IMR) under the Ministery of Health are both registered as institutional Global Salmonella Surveillance (GSS) members. As GSS members both the institutions are expected to send data to the Regional GSS center in Bangkok regularly. The GSS network has since expanded to include other foodborne diseases of interest for example campylobacter species.
Effective and efficient food borne disease surveillance will help ensure the quality and safety of food consumed. It should have a global approach in order to enhance the detection and response of food borne illness and act as an early warning system for any outbreak or crisis which may occur at any level, i.e. national, regional or international. The system should therefore be comprehensive and integrated with food monitoring data along the entire feed-food chain. This would result in robust surveillance and allow appropriate priority setting and public health intervention. Currently, several agencies and stakeholders from multiple disciplines at various levels are involved in the surveillance of food borne diseases, namely the Ministry of Health, Ministry of Agriculture and Agrobased Industries, food industries, laboratories and universities. The proposed national surveillance centre for the active surveillance of foodborne diseases would attempt to collaborate and coordinate the related activities of these agencies so that a unified surveillance system for foodborne diseases emerge.
The proposed national surveillance centre for the active surveillance of foodborne diseases would address some of the challenges posed. It is aimed to strengthen and enhance the existing foodborne disease surveillance and food contaminants data collection system. Data and information collected through its networking system could be utilized through coordinated activities by all sectors dealing with foodborne disease surveilance and food safety. This would support the development of evidence based disease prevention and control activities and assist in determining the true dimension of the burden of foodborne diseases. It would improve the ability to link pathogen in the food to disease in humans. Coordinated enforcement activities should be strengthened in an effort to lower the risk of foodborne diseases. Training and capacity building programmes with sufficient resources for development of technical expertise and infrastructure improvements have to be looked into. Measures to strengthen national capacity and infrastructure for laboratory based surveillance have also to be addressed. Ultimately this networking system could link with regional and international networking systems and help facilitate timely recognition of emerging foodborne diseases.
Foodborne diseases are an important public health problem as they not only affect human health, but also have a significant impact on economic and trade issues. Surveillance of foodborne diseases provides valuable information in the estimation of burden of foodborne diseases and in the rapid detection and response to outbreaks. Through an integrated and coordinated surveillance mechanism, data from all related sectors could be utilised in improving food safety and thus lowering the risk of foodborne diseases.
Foodborne disease monitoring and surveillance systems (paper prepared by the Government of Malaysia): FAO/WHO Regional Conference on Food Safety for Asia Pacific Region, Seremban, Malaysia, 24-27 May 2004.
Foodborne Disease In Malaysia. V K E Lim. Malaysian Medical Journal. 57: 1 -2, 2002.
Proposal for Setting-up of the foodborne active surveillance network (MyFoodNet). Wan Mansor Hamzah. Proposal Paper to Ministry of Health Malaysia.. 2004
Syndromic Notification And Laboratory Investigation Manual. Ministry of Health Malaysia. 2004.
Malaysia's Health 2002: Technical report of The Director-General of Health Malaysia. Ministry of Health Malaysia.2002
Food safety and food-borne illness. WHO. http://www.who.int/mediacentre/factsheets/fs237/en/. 2002
Food-borne diseases, emerging. WHO. http://www.who.int/mediacentre/factsheets/fs124/en/. Revised January 2002