The antibiotic-resistant ESBL bacteria are showing up more often in the food chain and within the population. There is partial overlap between the bacteria related to animals and that related to humans.
The ESBL bacteria, which are resistant against major antibiotics such as penicillin, have nowadays been detected in all meat-producing chicken suppliers, say the two research institutes. In addition, the bacteria are also present in 40 percent of pig rearing concerns and in more than half of those producing veal. The presence of ESBL bacteria among cows fluctuates strongly.
Livestock farmers are also affected by the resistant gut bacteria, but a direct link between humans and animals has not been established. While a third of the poultry farmers are carriers of ESBL, only 20 percent of their bacteria have been found in the chickens in their farms. In addition, 40 percent of pig farmers are infected by the bacteria, but in half of these cases, this does not concern farms where the bacteria are found in pigs. The spread of the resistant bacteria has progressed erratically, add the researchers. It has been found that the ESBL bacteria carried by a portion of the farmers are always genetically related to the bacteria in their animals.
Meanwhile, ESBL bacteria have also been found in the guts of pets such as dogs, in vegetables and in the surroundings. Moreover, the bacteria are not only increasingly found in hospital patients but also in healthy people. 'Because people are exposed to many different potential ESBL sources - food, the environment, pets and other humans - the extent of the influence from the various sources cannot be estimated yet,' conclude the veterinary researchers. This makes it difficult to develop a plan to tackle the further spread of ESBL. CVI and the Utrecht University say that more research needs to be done urgently into this pressing problem.