Campylobacter was found at most beef cattle farms and a quarter of them had Shiga toxin-producing E. coli, according to a Dutch study.
The National Institute for Public Health and the Environment (RIVM) and Netherlands Food and Consumer Product Safety Authority (NVWA) investigated in 2017 how often some pathogens occurred in beef cattle. RIVM assessed whether the same pathogens also occurred in the participants.
RIVM and NVWA advised that people can reduce their risk of infection by only eating beef that has been thoroughly cooked and by preventing other food, utensils and common surfaces from coming into contact with raw meat.
E. coli and Salmonella, and a variety of other pathogens sometimes found in beef, pose a risk for consumers when they eat contaminated beef and for farmers and visitors through direct contact with cattle.
Pathogens were frequently found in the studied cattle. They were present in the animals’ intestines and manure. Meat can become contaminated in the slaughterhouse if it comes in direct contact with manure.
The study involved cattle at 196 farms as well as 129 livestock farmers plus family members and employees. Manure samples were taken at the farms and analyzed for Campylobacter, Salmonella, ESBL-producing E. coli, Shiga toxin-producing E. coli (STEC) and Cryptosporidium. Fecal samples from farmers, employees and family members were examined for the same zoonotic pathogens.
Campylobacter was detected at 86 percent of the farms. For livestock farmers and family members, it was found in 2 percent of the research participants. Campylobacter is the main cause of food infections in the Netherlands, according to public health statistics with the number of infections in the country was estimated at about 67,000 in 2017.
A selection of 97 Campylobacter isolates from cattle farms were typed and tested for susceptibility to antibiotics such as ciprofloxacin, naladixic acid and tetracycline. Of these isolates, 90 were classed as Campylobacter jejuni and seven as Campylobacter coli.
The analysis found presence of dairy cattle on the farm was a significant risk factor for the occurrence of Campylobacter but having pigs had the opposite effect. This likely has more to do with factors such as hygiene measures than with the actual presence of the pigs. Companies without hygiene measures for non-professional visitors were also less at risk for Campylobacter but the reason for this was unclear.
The presence of Cryptosporidium was not confirmed on any of the farms. A third of participants use gloves when performing certain activities on the beef farm and handwashing was more often done when leaving than when entering the stable.
E. coli findings
STEC and Extended Spectrum Beta-Lactamase (ESBL)-producing bacteria were less prevalent in cattle and were found at 25 percent and 15 percent of the farms, respectively. A total of 393 STEC patients were registered in 2017.
STEC was detected at 48 beef farms resulting in 54 isolates being found in this study. E. coli O157:H7 was found at eight companies. Other strains of E. coli that were detected were O136:H12, O182:H25, O116:H28 and O168:H8.
Four variables were associated with the presence of STEC on the farm. Presence of sheep on the farm and use of a grazing scheme were protective but not seeing any signs of disease in cattle in the last six months and horticulture as a branch of industry appeared to be risk factors for STEC.
One participant was a carrier of STEC and ESBL-producing bacteria were found in 7 percent of participants. ESBL-producing bacteria were assessed as if a patient gets infected with ESBL-producing bacteria, options for treating the infection with antibiotics are more limited.
A total of 61 ESBL-producing E. coli isolates were found at 28 different companies. No resistance was found to colistin, to carbapenem antibiotics, meropenem, imipenem and ertapenem, or to tigecycline.
Salmonella was present in cattle at 4 percent of the farms. Mostly these were types of Salmonella which can cause diarrhea in people. Strains included Montevideo, Typhimurium monophasic 1,4,,12:i:- and Dublin.
It was not found in livestock farmers and family members. Salmonella causes an estimated 32,000 illnesses each year and about 1,000 are admitted to hospital..
(To sign up for a free subscription to Food Safety News, click here.)