Enterococcus faeciumStrains withvanA-Mediated High-Level Glycopeptide Resistance Isolated from Animal Foodstuffs and Fecal Samples of Humans in the Community

Abstract

The occurrence and the further spread of high-level glycopeptide-resistant, vanA-positive Enterococcus faecium strains outside of hospitals have been investigated. We could isolate such bacteria directly from thawing liquids of commercially produced frozen poultry (chickens, turkeys; no further data on previous feeding with avoparcin were available). In 5 of 13 samples of raw minced meat of pigs originating from 13 different butcher's shops, glycopeptide-resistant E. faecium (VanA type) could be detected after overnight broth cultivation of these samples. No glycopeptide-resistant enterococci could be isolated from meat samples of chickens that were fed without avoparcin. VanA type E. faecium strains were also identified in 12 fecal samples recovered from 100 nonhospitalized humans in the rural area of Saxony-Anhalt federal county. These results suggest a possible role of the food chain in the spread of glycopeptide-resistant E. faecium. Molecular typing (macrorestriction and multilocus enzyme analysis) reveal a wide dissemination of the vanA gene among strains of different ecological origins.

Current Trends of Emergence and Spread of Vancomycin-Resistant Enterococci

“…Large studies were initiated when higher numbers of VRE were suspiciously found in environmental samples without any known reservoir in or link to use of glycopeptides in human medicine (Klare et al, 1993;Torres et al, 1994). Soon after, avoparcin, another glycopeptide class antibiotic used in animal husbandry as a feed additive (growth promoter) was identified to select VRE in the animal setting (Bates et al, 1994;Klare et al, 1995a;Klare et al, 1995b;Bates 1997). Consequently, meat samples from commercially raised animals were highly contaminated with VRE including samples of pork, beef, chicken and turkey (Klare et al, 1995a;Klare et al, 1995b;Schouten et al, 1997;Klein et al, 1998;Simonsen et al, 1998;Kruse et al, 1999).…”

“…Soon after, avoparcin, another glycopeptide class antibiotic used in animal husbandry as a feed additive (growth promoter) was identified to select VRE in the animal setting (Bates et al, 1994;Klare et al, 1995a;Klare et al, 1995b;Bates 1997). Consequently, meat samples from commercially raised animals were highly contaminated with VRE including samples of pork, beef, chicken and turkey (Klare et al, 1995a;Klare et al, 1995b;Schouten et al, 1997;Klein et al, 1998;Simonsen et al, 1998;Kruse et al, 1999). Samples from organic or private farms of smaller sizes that did not use avoparcin or feed additives at all were free of VRE (Klare et al, 1995b;Klare and Witte 1998).…”

Performance of three chromogenic VRE screening agars, two Etest® vancomycin protocols, and different microdilution methods in detecting vanB genotype Enterococcus faecium with varying vancomycin MICs

“…Diagnostic and university laboratories send strains to us for (vancomycin/teicoplanin) resistance confirmation and molecular typing. Our enterococcal strain collection currently contains > 10,000 isolates, mainly from hospital surveillance and infections, but also from animals, food products, the environment, and stool colonisations in outpatients (Klare et al, 1995a, Klare et al, 1995b, Klare et al, 1999, Klare et al, 2005, Werner et al, 2007, Werner et al, 2010and Werner et al, 2011a. Until now, we collected and identified 1060 vanB strains including 982 vanB-positive E. faecium and 74 vanB-positive E. faecalis which were all from hospital patients.…”

Vancomycin-Resistant Enterococci (VRE) as Normal Flora of the Intestine in Patients at a Tertiary Care Hospital

“…VRE have been isolated from sewage treatment plants, 28,29 from the fecal samples of broiler chicken, thawing liquids of commercially produced frozen chicken and turkey, chicken and pig farms and minced meat of pigs in Europe. [30][31][32] In almost all the cases, VRE were associated with the use of glycopeptide avoparcin (Avotan, Cyanamid International) as a growth promoter in the animal feed, and were not found in farms or meat samples of chicken that were fed without avoparcin. [30][31][32] These findings suggest that hospitals may not be the only source of VRE and other factors may exert a selective pressure.…”

“…[30][31][32] In almost all the cases, VRE were associated with the use of glycopeptide avoparcin (Avotan, Cyanamid International) as a growth promoter in the animal feed, and were not found in farms or meat samples of chicken that were fed without avoparcin. [30][31][32] These findings suggest that hospitals may not be the only source of VRE and other factors may exert a selective pressure. We believe that investigation of environmental sources, poultry farms and cattle farms in Saudi Arabia for the presence of VRE would indicate the extent of the problem in this part of the world.…”