Control of Salmonella in Swedish cattle herds Jonas Carlsson Växa Sverige Seminar at SLU in Uppsala 6 April 2017
Background In 1953 a severe domestic outbreak of S. Typhimurium involved more than 9000 people Since than the strategy has been to prevent Salmonella in all parts of the production chain When Sweden joined EU 1995 the Swedish control program was accepted and additional guarantees were achieved Around 3000 human cases is reported yearly and 75-80 % are infected abroad
Notified incidence of Salmonella in Swedish cattle herds during 1968-2015 Surveillance of Infectious diseases in animals and humans in Sweden 2015 Report National Veterinary Institute, et al.
Short about the Swedish Salmonella control program All findings of Salmonella is notifiable and actions is taken to eliminate contamination or infections Animal feed, the operators is responsible producing S-free feed Animals, investigations is required upon clinical suspicion Food, contaminated food products is considered unfit for human consumption Humans, salmonellosis in humans is notifiable and a trace back investigation is completed for all domestic cases
Surveillance in the Swedish Salmonella control program Feed, focus on feed raw materials, heat treatment and prevention for recontamination Feed mills, sampling from the processing line and feed mill environment Food enterprises, in house control programs common Abattoirs, approx. 20 000 samples per year Cutting plants, approx. 5000 samples per year (red meat)
Control in cattle herds Compulsory part investigations upon clinical suspicion Sampling from postmortem investigations All imported animals are sampled When Salmonella is confirmed on a farm, the holding is put under restrictive measures, an investigation will be done and a plan to eradicate Salmonella is designed. Animals to and from the farm is stopped. Voluntary parts Preventive biosecurity program Smittsäkrad besättning Holdings affiliated to the program receive higher compensation in case of positive findings
Smittsäkrad besättning A biosecurity program for cattle herds in Sweden
Developed 2011-2015 (state funded), launched in 2015 Växa Sverige operates the program (assigned by the Swedish Board of Agriculture) Optional for farmers to affiliate, yearly fee 985 sek
To reduce the spread of infectious diseases between and within cattle farms Which implies: - a positive effect on animal health and animal welfare - a safe food production and a reduced risk for spread of zoonotic diseases - a reduced cost for the society and farmers regarding controlling infectious animal diseases
State economic compensation in case of Salmonella Relevant education and advice - increased knowledge Different program levels Farmer-to-farmer communication User friendly solutions Group pressure Demand and/or decreased fee insurance companies
On-farm education Veterinary inspection & advice Web based biosecurity risk assessment questionnaire Web based education Controlled animal movements Biosecurity advice service when planning new buildings for cattle
On-farm education Veterinary inspection & advice Web based biosecurity risk assessment questionnaire Web based education Controlled animal movements
Web based questionnaire regarding biosecurity routines and facilities of the farm Divided into 7 areas Animal contact, visitors/staff, transport/equipment, hygiene/health monitoring, feed, manure, surroundings Result after each section along with advice Results saved on the program page Repeated every 18-24 months
Linked to hands on advice for each area at www.smittsakra.se
On-farm education Veterinary inspection & advice Web based biosecurity risk assessment questionnaire Web based education part 1 Controlled animal movements
Based on: - Results of the risk assessment - Results of the checkpoints Support to the veterinarians: - Education - Guidelines - Access to notes from previous veterinary visits in the program
On-farm education Veterinary inspection & advice Web based biosecurity risk assessment questionnaire Web based education part 1 Controlled animal movements
Focus course Workshops with owner and employees Motivation through education On farm near the animals Practical exercises On-farm education
On-farm education Veterinary inspection & advice Web based biosecurity risk assessment questionnaire Web based education Controlled animal movements
Regulations in Smittsäkrad besättning for purchase of animals - From BVDV free herds - Born in Sweden (dairy herds) - Import controlled by SDS - Isolation on farm demand if ingoing animals from > 5 herds Recommendations: use Säker livdjurshandel in animal trade
A program for safe animal trade
Säker Livdjurshandel (SÄL) = tools for safe animal trade Subscription of milk analyses Single sampling occasion kit Health declaration forms Advice for the seller/purchaser
Subscription of milk analyses Four samples/year on bulk tank milk Salmonella PrioCHECK Salmonella Antibody bovine ELISA and PrioCHECK Salmonella Ab bovine Dublin ELISA, Thermo Fischer Scientific Streptococcus agalactiae and Mycoplasma bovis Thermofischer Pathoproof Immuno Assay x- kit Two samples/year on pooled milk from 3 primiparous cows (test milking scheme) BRSV SVANOVIR BRSV-Ab
The Green list Four successive negative samples (Salmonella, M. bovis and Str. agalactiae) -> Green list Herds in milk recording have also info about BRSV-status (yellow=positive)
Green list gives also info about how many contact herds latest 12 month
Health declaration forms Farmers own declaration regarding the disease status of the herd, Eg. SCC, digital dermatitis, ringworm, parasites, symptoms of diarrea/cough Also to raise awareness of the risks involved in animal trading
Increasing costs due to: Increasing herd size In average longer time under restriction Epizootic attitude
Skr per cattle Average compensation from government per animal vs herd size for eradication of Salmonella (cases 1999-2013) Herd size number of cattle Source: The Swedish Board of Agriculture
Notified incidence of Salmonella in Swedish cattle herds during 1968-2015 Surveillance of Infectious diseases in animals and humans in Sweden 2015 Report: National Veterinary Institute et al.
Results from serological screenings for Salmonella on bulk milk 2007: 4% (S Dublin 1.3 %) 2013: 3% (S Dublin 0.9 %) Source: National Veterinary Institute and Board of Agriculture
What s the problem and there by the challenge in future? More and more expensive eradications in relatively few herds, with little impact on national prevalence National screenings showed that the true prevalence is much higher, there is normally no restrictions on these herds Concerning public health it seems that the additional guarantees is most important
Some thoughts for the future Swedish Salmonella control program We have to be more cost-efficient in control Take full advantage of serological diagnostics Epizootic vs endemic perspective Secure animal trade not only for Salmonella but also for other relevant pathogens Spread knowledge, use an advisory service like in Denmark Avoid to overdramatize Salmonella
Pilot project Testing the danish model of eradication of salmonella Biosecurity risk scoring protocol to identify critical infection routes Advice on action plan ELISA tests Follow-up
Thank you for listening! and special thanks to Sofie Andersson & Anna Ohlson