Enhancing the one health initiative by using whole genome sequencing to monitor antimicrobial resistance of animal pathogens: Vet-LIRN collaborative project with veterinary diagnostic laboratories in United States and Canada.

BACKGROUND: Antimicrobial resistance (AMR) of bacterial pathogens is an emerging public health threat. This threat extends to pets as it also compromises our ability to treat their infections. Surveillance programs in the United States have traditionally focused on collecting data from food animals, foods, and people. The Veterinary Laboratory Investigation and Response Network (Vet-LIRN), a national network of 45 veterinary diagnostic laboratories, tested the antimicrobial susceptibility of clinically relevant bacterial isolates from animals, with companion animal species represented for the first time in a monitoring program. During 2017, we systematically collected and tested 1968 isolates. To identify genetic determinants associated with AMR and the potential genetic relatedness of animal and human strains, whole genome sequencing (WGS) was performed on 192 isolates: 69 Salmonella enterica (all animal sources), 63 Escherichia coli (dogs), and 60 Staphylococcus pseudintermedius (dogs). RESULTS: We found that most Salmonella isolates (46/69, 67%) had no known resistance genes. Several isolates from both food and companion animals, however, showed genetic relatedness to isolates from humans. For pathogenic E. coli, no resistance genes were identified in 60% (38/63) of the isolates. Diverse resistance patterns were observed, and one of the isolates had predicted resistance to fluoroquinolones and cephalosporins, important antibiotics in human and veterinary medicine. For S. pseudintermedius, we observed a bimodal distribution of resistance genes, with some isolates having a diverse array of resistance mechanisms, including the mecA gene (19/60, 32%). CONCLUSION: The findings from this study highlight the critical importance of veterinary diagnostic laboratory data as part of any national antimicrobial resistance surveillance program. The finding of some highly resistant bacteria from companion animals, and the observation of isolates related to those isolated from humans demonstrates the public health significance of incorporating companion animal data into surveillance systems. Vet-LIRN will continue to build the infrastructure to collect the data necessary to perform surveillance of resistant bacteria as part of fulfilling its mission to advance human and animal health. A One Health approach to AMR surveillance programs is crucial and must include data from humans, animals, and environmental sources to be effective.

Serotype 10A in case patients with invasive pneumococcal disease: a pilot study of PCR-based serotyping in New Jersey.

In 2008, the New Jersey Department of Health (NJDOH) identified a 21.1% increase in reported invasive pneumococcal disease (IPD). In 2009, NJDOH piloted nucleic acid-based serotyping to characterize serotypes causing IPD. From April through September, NJDOH received specimens from 149 of 302 (49%) case patients meeting our case definition. An uncommon serotype, 10A, accounted for 25.2% of IPD overall and was identified in 12 counties, but it was associated with one county (rate ratio = 5.4, 95% confidence interval [CI] 2.1, 11.8). NJDOH subsequently conducted a case-control study to assess the presentation of and clinical risk factors for 10A IPD. Case patients with 10A IPD were more likely to have had immunosuppression, asthma, and multiple chronic medical conditions than control subjects had (odds ratio [OR] = 2.6, 95% CI 1.1, 6.3; OR=4.7, 95% CI 1.7, 13.2; and OR=2.3, 95% CI 1.0, 5.2, respectively). State-based pneumococcal serotype testing identified an uncommon serotype in New Jersey. Continued pneumococcal serotype surveillance might help the NJDOH identify and respond to future serotype-specific increases.