Development and evaluation of a risk-based sampling approach for the Swiss antibiotic resistance and residue monitoring programme

• Research unit: FSVO
• Project number: 1.05.06

Key words (German)

foreign substances monitoring - antimicrobial resistance - random sampling - risk factor analysis - risk-based sampling - risk-based model - cost-effectiveness

Key words (English)

foreign substances monitoring - antimicrobial resistance - random sampling - risk factor analysis - risk-based sampling - risk-based model - cost-effectiveness

Short description (English)

Antibiotics and pesticides are used in livestock production worldwide. As a consequence of this practice and also due to environmental exposure, a risk of chemical residues (foreign substances) and antibiotic resistant bacteria might exist for consumers of animal-derived products. Furthermore many consumers became more sensitive to food safety issues today, especially with regard to antibiotic residues or problems of antibiotic resistant bacteria in food of animal origin.
The Swiss chemical residue monitoring programme is an extensive programme to evaluate the occurrence of selected contaminants in animal products. It is co-ordinated by the Swiss Federal Veterinary Office (BVET) and has been conducted for more than 10 years in the past. Each year, large numbers of samples of animals and animal products are collected randomly and analysed for contaminants at a high cost. In order to increase the consumer's safety and the programme's cost-effectiveness, a targeted sampling plan for the monitoring of chemical residues and antibiotic resistance is proposed. This is in line with the guidlines of the EU, which encourages its member states to focus their monitoring programmes on those risk factor combinations where the probability to detect residues is highest.
Therefore, we aim to develop a protocol for a risk-based chemical residue and antimicrobial resistance monitoring programme. The protocol's development will be based on risk assessment methodology and will consider spatial and temporal risk factors. The proposed focus will be on the foreign substances cadmium, lead, sulphonamides and antimicrobial resistance. In close collaboration with Johanneum Research, Graz, we aim to compare the reliability and precision of random sampling versus sampling based on risk factor information and provide an economical assessment of the two sampling strategies and their appropriate combinations.
For the residue monitoring, known and as yet unidentified risk factors and resultant risk profiles will be incorporated in a scoring matrix to support risk ranking. In the field of antimicrobial resistance monitoring, several projects (e.g. NRP 49) already provide information on risk factors, profiling and ranking. For both monitoring programmes, the assessment will develop objective criteria that allow the identification of combinations of animal species, production type, and substance which require targeted sampling because of risk factors. To evaluate the precision and reliability of the proposed residue monitoring, stochastic simulation of monitoring data from risk-based and random sampling will be the method of choice. For antimicrobial resistance, the framework of the model developed for the NRP 49 project will be used and modified to include options for risk-based sampling.
A scientifically sound adaptation of the sampling design to the characteristics of the residue substance or the resistant bacteria under investigation is likely to improve the probability of detection and is therefore a benefit for consumer health.

Project aims (English)

The goal of this project is to develop and evaluate a targeted sampling plan for monitoring chemical foreign substances and antimicrobial resistance. The specific objectives are:

1) To assess risk factors for chemical foreign substances and antimicrobial resistance in different animal sub-
populations, species and their products, considering geographical areas and trends in time
2) To develop a protocol for risk-based sampling as part of the foreign substance monitoring programme using
risk assessment methods
3) To compare the reliability and precision of random sampling versus sampling based on risk factor information
4) To provide an economical assessment of the possible sampling strategy combinations

Publications / Results (German)

29.10.2009: Umsetzungssitzung 2009: Wurde soweit möglich umgesetzt (Aufnahme in Risiken für nationalen Untersuchungsplan). Weitere Umsetzung im Nachfolgeprojekt (Priorisierung der Kontrollen entlang der ganzen Kette), je nach Entscheide Brüssel. Neuer Status: „erledigt“ (mvo).

Related documents

• Datenblatt [PDF] 12 kB

Publications / Results (English)

Presi, P.; Stärk, KDC.; Knopf, L.; Breidenbach, E.; Sanaa, M.; Frey, J.; Regula, G. (2008) Efficiency of risk-based vs. random sampling for the monitoring of tetracycline residues in slaughtered calves in Switzerland. Food Additives and Contaminants, 25(5): 566–573.

Presi, P.; Knopf, L.; Regula, G.; Pacciarelli, B.; Frey, J.; Stärk, KDC. (2007). Evaluation of the chemical residue monitoring in animal-derived products in Switzerland. Food Additives and Contaminants 24:590-597.