Humans At Risk From Antibiotics In Food Animals

Antimicrobials are vital medicines to treat human infections, but their effectiveness is increasingly threatened by overuse and inappropriate use which contribute to the growing resistance of bacteria, says a new WHO report.

Some 70 experts in human and veterinary medicine meeting in Berlin said the excessive use of antimicrobials in livestock raising -- especially when used to boost growth -- led to the appearance of resistant microbes that can be transmitted through the food chain to humans.

The Berlin conference was organized by the Federal Institute of Health related to consumer protection and the Veterinary Medicine BgVV, a WHO/FAO (Food and Agriculture Organization) Collaborating Center for Research and Training in Food Hygiene and Zoonosis, in order to analyze the risks using antimicrobials in animals raised for food.

Resistant strains of four bacteria that cause disease in humans have been transmitted from animals to humans and have been shown to have consequences for human health. The four are salmonella, campylobacter, enterococci, and E. coli.

Direct evidence that antibiotic use in food-producing animals results in resistant salmonella infections in humans was presented at the meeting. "Although only a small proportion of infected people require antibiotic treatment, in these patients the options are severely limited by resistance," the experts concluded.

Participants at the conference cited the widespread use of fluoroquinolones, an important group of medical antibiotics, in food animals as a particularly important issue. Fluoroquinolone- resistant campylobacter has been detected in foods and has also been associated with treatment failure in humans infected with the bacteria.

The Berlin conference concluded that healthy livestock-raising methods reduced the need for antimicrobials, which they stressed should never be used as substitutes for adequate hygiene.

The report dismissed the arguments that lower use of antibiotics as growth boosters would cause reduced productivity or higher prices for consumers. Nor would it make it necessary to increase the use of other medicines to replace antibiotics, said the experts, who encouraged a search for alternative methods to boost the growth of food animals.

"We must be able to provide descriptive data on the extent and temporal trends of antibiotic susceptibility and facilitate the identification of resistance in humans, animals, and foods of animal origin, as it arises," said the BgVV's Dr. Helmuth Reiner, co-chairman of the meeting.

WHO announced that its Pan-American Health Office would hold a meeting in February to examine potential medical problems related to the use of fluoroquinolones in food animals.