Quantification of contacts between Dutch farms to assess the potential risk of foot-and-mouth disease spread

• Published in: Preventive veterinary medicine Vol. 28; no. 3; pp. 143 - 158
• Main Authors: Nielen, M., Jalvingh, A.W., Horst, H.S., Dijkhuizen, A.A., Maurice, H., Schut, B.H., van Wuijckhuise, L.A., de Jong, M.F.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.09.1996
• Subjects: Agrarische Bedrijfseconomie; BOVIN; CATTLE; CERDO; CONTROL DE ENFERMEDADES; CONTROLE DE MALADIES; DANGER POUR LA SANTE; DECISION MAKING; Decision support system; DISEASE CONTROL; DISEASE TRANSMISSION; Farm contacts; FIEBRE AFTOSA; FIEVRE APHTEUSE; FOOT AND MOUTH DISEASE; GANADO BOVINO; HEALTH HAZARDS; Infectious disease spread; MODELE DE SIMULATION; MODELOS DE SIMULACION; NETHERLANDS; PAISES BAJOS; PAYS BAS; PELIGRO PARA LA SALUD; PORCIN; PRISE DE DECISION; Risk; SIMULATION MODELS; SWINE; TOMA DE DECISIONES; TRANSMISION DE ENFERMEDADES; TRANSMISSION DES MALADIES; WIAS; Risk; Foot-and-mouth disease; Decision support system; Farm contacts; Infectious disease spread
• ISSN: 0167-5877; 1873-1716
• DOI: 10.1016/0167-5877(96)01042-2

Dutch data on the contacts between farms were collected in order to adapt a simulation model of a foot-and-mouth disease outbreak in the Netherlands. The data were collected in a geographically-defined area of approximately 33 km 2 in the eastern part of the Netherlands. In total 205 farmers were asked to participate, of which 144 subsequently reported all contacts on and off their farm during a 2-week period in December 1994. On average, 92 contacts occurred per farm during the 2-week period (median 81). Most animal movements consisted of pigs, which were transported in large groups. Cattle, particularly calves, tended to be transported individually. Social visits were responsible for a large number of contacts, and in 25% of these visits the persons had contact with the farm animals, causing the contact to be a high risk for spread of foot-and-mouth disease. Pig farms had the lowest number of contacts; cattle farms and mixed pig and cattle farms had more contacts, respectively. Linear-regression models to predict the number or distance of the contacts per farm, with characteristics such as farm size or farm type had extremely low predictive values. The collected data gave an indication of the contact pattern between Dutch farms in the winter period, in a well-defined small area of the Netherlands. The contact pattern would be expected to change drastically after the declaration of an outbreak of foot-and-mouth disease, because of the movement restrictions that would be imposed. Data from the current study can, therefore, only be used to show how foot-and-mouth disease could spread prior to diagnosis.