VanB-VanC1 Enterococcus gallinarum, Italy

To the Editor: We report detecting a vanB determinant in Enterococcus gallinarum in poultry in Italy. High-level vanA-mediated glycopeptide resistance has been described for E. gallinarum and E. casseliflavus (1–4), and vanB-mediated vancomycin resistance has been frequently described for E. faecalis and E. faecium. However, vanB-mediated resistance in isolates of E. gallinarum has been described only in sporadic nosocomial cases of infection or colonization (5,6). 
 
In January 2005, a study of contamination by foodborne organisms in slaughtered broiler carcasses was conducted in Sicily. To detect glycopeptide-resistant enterococci (GRE), each carcass was placed in a bag with 100 mL sterile buffered peptone water and shaken vigorously for 60 sec. After overnight incubation at 37°C, 0.5 mL rinsate was added in duplicate to 5 mL ethyl violet azide broth (Oxoid, Basingstoke, United Kingdom) with 4 mg/L vancomycin. Broth cultures were further incubated at 37°C for 48 h, and 0.1 mL aliquots were spread onto duplicate plates of VRE (commercial denomination product, Oxoid) agar. 
 
A vancomycin-resistant isolate of E. gallinarum was identified in a carcass from a broiler farm in eastern Sicily. The biochemical tests of API 20 Strep (bioMerieux, Marcy l'Etoile, France) and motility test at 30°C were used to characterize the isolate at the species level. The MICs of vancomycin and teicoplanin were 64 μg/mL and 1 μg/mL, respectively. The isolate was subjected to a multiplex polymerase chain reaction followed by an endonuclease cleavage of amplicons by MspI (Invitrogen, Carlsbad, CA, USA) as previously described (7) to detect van gene determinants; this process demonstrated a simultaneous presence of vanC1 and vanB determinants. 
 
E. gallinarum and the other motile enterococci are thought to infrequently cause infection. However, the recent involvement of vanC1-vanA E. gallinarum in person-to-person spread in a long-term-care facility (8) and in an intensive care unit (2), along with identification of vanC1-vanB isolates in some patients treated with prolonged courses of glycopeptides (5,6), suggests reassessment of their possible pathogenic role. 
 
For the first time, 1 isolate of E. gallinarum has been found harboring the vanB gene in poultry. Our findings confirm that E. gallinarum can capture the genetic determinants of high-level glycopeptide resistance, probably under selective pressure conditions that do not permit survival of a host organism with constitutive low-level resistance (3). Previous studies have demonstrated that E. gallinarum can transfer these determinants to E. faecium by conjugation (2). 
 
The role of food animals as reservoirs of GRE and the causes of their persistently high prevalence in poultry carcasses in some European countries are being investigated (9). Moreover, the public health risk associated with consumer exposure to GRE when handling raw animal foods is poorly understood. In Europe, the food chain is thought to be the major source of GRE since avoparcin was used as a food additive for animals until the European Union ban in 1997. Previous studies in Italy showed that avoparcin withdrawal successfully reduced GRE contamination of poultry meat products (10). However, our finding, 7 years after the European Union ban, highlights that resistance genotypes in motile enterococci should be closely monitored (11).

Simultaneous tracking of human and animal diseases was considered useful by 32 (84%) of 38 respondents because animals are sentinels of human (zoonotic) disease and by 7 (18%) respondents because of the threat of agroterrorism. In general, respondents are aware of the importance of animal disease reporting to public health.
In Michigan, the human and animal disease reporting systems are similarly structured, although there is no local level animal health agency (Figure). These similarities can provide the basis for a system that is functionally appropriate to track diseases in humans and multiple animal species and meet multiple agency surveillance objectives.
Overall, this group of Michigan veterinarians considers developing a Web-based disease reporting system as useful as long as the following issues are addressed: 1) quality case report feedback; 2) access to correct and coordinated human and animal disease information; and 3) computer system reliability and efficiency. Based on the results of this study, the second phase of this project, construction of the animal disease surveillance portion of Michigan's reporting system, will be implemented with continued input from local, state, and federal stakeholders.
Funding from the Michigan Department of Community Health supported this study.

VanB-VanC1 Enterococcus gallinarum, Italy
To the Editor: We report detecting a vanB determinant in Enterococcus gallinarum in poultry in Italy. Highlevel vanA-mediated glycopeptide resistance has been described for E. gallinarum and E. casseliflavus (1)(2)(3)(4), and vanB-mediated vancomycin resistance has been frequently described for E. faecalis and E. faecium. However, vanB-mediated resistance in isolates of E. gallinarum has been described only in sporadic nosocomial cases of infection or colonization (5,6).
In January 2005, a study of contamination by foodborne organisms in slaughtered broiler carcasses was conducted in Sicily. To detect glycopeptide-resistant enterococci (GRE), each carcass was placed in a bag with 100 mL sterile buffered peptone water and shaken vigorously for 60 sec. After overnight incubation at 37°C, 0.5 mL rinsate was added in duplicate to 5 mL ethyl violet azide broth (Oxoid, Basingstoke, United Kingdom) with 4 mg/L vancomycin. Broth cultures were further incubated at 37°C for 48 h, and 0.1 mL aliquots were spread onto duplicate plates of VRE (commercial denomination product, Oxoid) agar.
A vancomycin-resistant isolate of E. gallinarum was identified in a carcass from a broiler farm in eastern Sicily. The biochemical tests of API 20 Strep (bioMérieux, Marcy l'Etoile, France) and motility test at 30°C were used to characterize the isolate at the species level. The MICs of vancomycin and teicoplanin were 64 µg/mL and 1 µg/mL, respectively. The isolate was subjected to a multiplex polymerase chain reaction followed by an endonuclease cleavage of amplicons by MspI (Invitrogen, Carlsbad, CA, USA) as previously described (7) to detect van gene determinants; this process demonstrated a simultaneous presence of vanC1 and vanB determinants.
E. gallinarum and the other motile enterococci are thought to infrequently cause infection. However, the recent involvement of vanC1-vanA E. gallinarum in person-to-person spread in a long-term-care facility (8) and in an intensive care unit (2), along with identification of vanC1-vanB isolates in some patients treated with prolonged courses of glycopeptides (5,6), suggests reassessment of their possible pathogenic role.
For the first time, 1 isolate of E. gallinarum has been found harboring the vanB gene in poultry. Our findings confirm that E. gallinarum can capture the genetic determinants of highlevel glycopeptide resistance, proba-bly under selective pressure conditions that do not permit survival of a host organism with constitutive lowlevel resistance (3). Previous studies have demonstrated that E. gallinarum can transfer these determinants to E. faecium by conjugation (2).
The role of food animals as reservoirs of GRE and the causes of their persistently high prevalence in poultry carcasses in some European countries are being investigated (9). Moreover, the public health risk associated with consumer exposure to GRE when handling raw animal foods is poorly understood. In Europe, the food chain is thought to be the major source of GRE since avoparcin was used as a food additive for animals until the European Union ban in 1997. Previous studies in Italy showed that avoparcin withdrawal successfully reduced GRE contamination of poultry meat products (10). However, our finding, 7 years after the European Union ban, highlights that resistance genotypes in motile enterococci should be closely monitored (11).