This means that ESBLs are only acquired to a ‘limited extent’ via livestock and through eating meat.
They said risk is small if meat is sufficiently cooked and adequate hygiene measures are followed.
Extended Spectrum Beta Lactamase (ESBL) is an enzyme, produced by certain bacteria, which makes them resistant to antibiotics such as penicillins and cephalosporins.
Frequent occurrence
ESBLs occur frequently in livestock, the food chain, environment and in people but transmission mainly occurs between humans.
Poultry meat is most often contaminated while ESBLs are found less frequently in other livestock species.
Researchers are from Wageningen University, Utrecht University, the Dutch National Institute for Public Health and the Environment (RIVM), University Medical Center Utrecht and GD Animal Health.
The work is part of 1Health4Food – a public-private research consortium in animal and human health.
The most common ESBLs include TEM, SHV and CTX-M. About 5% of the Dutch population carry ESBLs in their intestines.
Humans not food importance transmission source
The work found similarities between ESBLs from healthy carriers and people with an infection caused by these bacteria. This means humans are an important source for transmission of ESBLs to other people.
Researchers discovered ESBLs in pets, wild birds, poultry, pigs, cattle and surface water.
However, the ESBLs in livestock and meat showed little genetic similarity with those in humans.
“It is therefore a misconception that humans mainly acquire ESBLs through eating meat (especially chicken meat). If the meat is sufficiently cooked and there are adequate hygiene measures in the kitchen, then the chance of people being exposed to ESBLs is small,” said researchers.
“The differences found between ESBLs in humans and in livestock farming suggest that farmed animals, including poultry and poultry meat, make a relatively small contribution to ESBLs that occur in humans compared to the human contribution itself.”
People who work with animals, such as livestock farmers and abattoir employees, have a higher chance of carrying ESBLs.
ESBLs of livestock farmers and their livestock do exhibit a high degree of similarity due to intensive and direct contact.
Disease burden of food-related pathogens
In other work, RIVM estimated the cost-of-illness (COI) related to 14 food-related pathogens for 2016.
Costs associated with the pathogens transmitted to people by food was €171m. This is almost as much as in 2015 (€172m). It includes healthcare and costs for the patient and/or family such as travel expenses.
Food-related disease burden is expressed in Disability Adjusted Life Year (DALY), a measure for the sum of the Years Lost due to Disability (YLD) and Years of Life Lost (YLL) due to premature mortality in a population.
The number of DALYs due to the pathogens is estimated at 4,708 in 2016 which is higher than 2015 (4,642 DALY's).
Investigated pathogens were Campylobacter spp; Salmonella spp; Cryptosporidium spp; rotavirus; Giardia spp; norovirus; Listeria monocytogenes; Toxoplasma gondii; STEC O157; hepatitis A; hepatitis E; Bacillus cereus; Clostridium perfringens and Staphylococcus aureus.