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Seventy-eight isolates of different Enterococcus species (E. faecalis, n ‫؍‬ 27; E. faecium, n ‫؍‬ 23; E. durans, n ‫؍‬ 8; E. avium, n ‫؍‬ 6; E. hirae, n ‫؍‬ 9; E. gallinarum, n ‫؍‬ 3; and E. casseliflavus, n ‫؍‬ 2) with a variety of erythromycin resistance phenotypes were examined for the presence of macrolide resistance genes (ermA, ermB, ermC, ermTR, mefA/E, and msrA). Positive PCR amplifications of ermB were obtained for 39 of 40 highly erythromycin-resistant Enterococcus isolates (MICs, >128 g/ml) of different species; the remaining highly resistant E. faecium isolate was positive for PCR amplification of ermA but was negative for PCR amplification of the ermB and ermC genes. For all enterococcal strains for which erythromycin MICs were <32 g/ml PCRs were negative for erm methylase genes. For all E. faecium isolates PCR amplified products of the expected size of 400 bp were obtained when msrA primers were used, with the results being independent of the erythromycin resistance phenotype. All the other enterococcal species gave negative results by msrA PCRs. Sequencing of the msrA PCR products from either erythromycin-susceptible, low-level-resistant, or highly resistant E. faecium strains showed that the amplicons did not correspond to the msrA gene described for Staphylococcus epidermidis but corresponded to a new putative efflux determinant, which showed 62% identity with the msrA gene at the DNA level and 72% similarity at the amino acid level. This new gene was named msrC.Over the last few years, Enterococcus has emerged as an important bacterial pathogen in nosocomial infections (13). The acquisition of specific mechanisms of resistance to different antibiotics, especially for the species Enterococcus faecium, has rendered infections with these microorganisms difficult to treat (8, 25); in just 10 years, antibiotic resistance has spread rapidly among enterococci and has become an important public health concern (11, 14). Macrolide-lincosamide-streptogramin (MLS) antibiotics constitute an alternative therapy for the treatment of insidious enterococcal infections. Three different mechanisms account for the acquired resistance to MLS antibiotics in gram-positive bacteria: modification of the drug target, inactivation of the drug, and active efflux of the antibiotic. In the first case, a single alteration of the 23S rRNA confers broad cross-resistance to macrolide-lincosamide-streptogramin B (MLS B ) antibiotics, whereas the inactivation mechanism confers resistance only to structurally related MLS antibiotics. Regarding the pump mechanisms, the mefA (4), mefE (34), msrA (29), and mreA (5) genes have been involved in the active efflux of macrolides in gram-positive bacteria. The mef and mreA genes have been associated with macrolide resistance, and the msrA gene has been associated with macrolide and streptogramin B resistance. Erythromycin resistance by erm methylases of the ermB-ermAM hybridization class has been described in Enterococcus isolates (3,15,19). However, even though some reports indicate the ...

Pets from COVID‐19 owners were screened for SARS‐CoV‐2 (April‐May 2020). From 23 pets, an asymptomatic cat showed positive RT‐qPCRs results from oropharyngeal swab (negative rectal swab). Remaining pets were negative. This suggests that cats can contract the virus from their infected owners and may act as potential hosts for SARS‐CoV‐2. Their role in carrying live or infectious viruses and disseminating them needs more investigation.