47% of poultry and meat samples were found to be contaminated with Staphylococcus aureus bacteria, and half of those with bacteria resistant to three or more classes of antibiotics, researchers from the Translational Genomics Research Institute wrote in the journal Clinical Infectious Diseases.
Strains of drug resistant Staphylococcus aureus, also known as S. aureus, are bacteria associated with several human diseases and appear to be widespread in the poultry and meat sold in American retail outlets. The researchers were surprised the contamination rate was so high.
The authors explain that theirs is the first nationwide assessment of contamination of the U.S. food supply with antibiotic resistant S. aureus.
According to the results of genetic (DNA) tests that were carried out, it appears that the major source of contamination is from livestock (farm animals).
Proper cooking of S. aureus tainted poultry and meats should kill off all bacteria. However, there is a risk of human infection if the food is not handled properly during the preparation of meals.
136 samples, including 80 different brands of turkey, pork, beef and chicken were gathered from 26 retail outlets in Washington D.C., Fort Lauderdale, Chicago, Los Angeles and Flagstaff.
Senior author, Lance B. Price, Ph.D., said:
“For the first time, we know how much of our meat and poultry is contaminated with antibiotic-resistant Staph, and it is substantial.
The fact that drug-resistant S. aureus was so prevalent, and likely came from the food animals themselves, is troubling, and demands attention to how antibiotics are used in food-animal production today.”
The authors explained that highly industrialized farming, where animals are densely packed together and fed steady low doses of antibiotic, are perfect breeding grounds for drug-resistant bacteria to thrive, and then make their way into humans.
Dr. Price said:
“Antibiotics are the most important drugs that we have to treat Staph infections; but when Staph are resistant to three, four, five or even nine different antibiotics – like we saw in this study – that leaves physicians few options.”
Paul S. Keim, Ph.D., co-author, said:
“The emergence of antibiotic-resistant bacteria – including Staph – remains a major challenge in clinical medicine.
This study shows that much of our meat and poultry is contaminated with multidrug-resistant Staph. Now we need to determine what this means in terms of risk to the consumer.”
Although US authorities routinely check meats and poultry for four different types of drug-resistant bacteria, the checks do not include S. aureus. The authors urge the US government to improve its inspection program.
S. aureus is the most common cause of staph infections. Many people carry the bacteria in their nose and on their skin. According to the NHS (National Health Service), UK, approximately 20% of humans are long-term carries of S. aureus.
S. aureus can cause pimples, impetigo, boils, cellulitis, folliculitis, scalded skin syndrome, abscesses, pneumonia, meningitis, endocarditis, toxic shock syndrome, chest pain, bacteremia and sepsis. It can also cause serious post-surgical wound infections.
The treatment of choice for S. aureus infection is penicillin. However, resistance has been growing and doctors often have to find other antibiotics. Fifty years ago drug resistant S. aureus was virtually unheard of.
Source: Translational Genomics Research Institute
Written by Christian Nordqvist