An article about airborne multidrug-resistant bacteria that is found isolated from a concentrated swine feeding operation. It was noted that the use of nontherapeutic levels of antibiotics in swine production can choose for antibiotic resistance in commensal and pathogenic bacteria in swine. As a result therefore, retail pork products, as well as surface and groundwaters contaminated with swine waste, have been shown to be sources of human exposure to antibiotic-resistant bacteria. However, it is not certain whether the air within swine operations also serves as a basis of exposure to antibiotic-resistant bacterial pathogens. Thus to investigate this issue, the air was being sampled within a concentrated swine feeding operation with an all-glass impinger. Samples then were analyzed and examined using a method for the isolation of Enterococcus. There were a total of 137 presumptive Enterococcus isolates identified to species level using standard biochemical tests and analyzed for resistance to erythromycin, clindamycin, virginiamycin, tetracycline, and vancomycin by means of the agar dilution method. Thirty four percent of the isolates were confirmed as Enterococcus, 32 percent were identified as coagulase-negative staphylococci, and 33 percent were identified as viridans group streptococci. Regardless of bacterial species, 98 percent of the isolates expressed high-level resistance to at least two antibiotics usually used in swine production. None however, of the isolates were resistant to vancomycin. Vancomycin is an antibiotic in the United States that has never been approved for use in livestock. In conclusion, high-level multidrug-resistant Enterococcus, coagulase-negative staphylococci, and viridans group streptococci were detected in the air of a concentrated swine feeding operation. These findings imply that the inhalation of air from these facilities may serve as an exposure pathway for the transfer from swine to humans of multidrug-resistant bacterial pathogens.
Original Text:
http://www.ehponline.org/docs/2004/7473/abstract.html
