Molecular Epidemiology and Antimicrobial Resistance of Outbreaks of Klebsiella pneumoniae Clinical Mastitis in Chinese Dairy Farms

Shaodong Fu; Chen Wen; Zhenglei Wang; Yawei Qiu; Yihao Zhang; Jiakun Zuo; Yuanyuan Xu; Xiangan Han; Zhenhua Luo; Wei Chen; Jinfeng Miao

doi:10.1128/spectrum.02997-22

Microbiology Spectrum (Dec 2022)

Molecular Epidemiology and Antimicrobial Resistance of Outbreaks of Klebsiella pneumoniae Clinical Mastitis in Chinese Dairy Farms

Shaodong Fu,
Chen Wen,
Zhenglei Wang,
Yawei Qiu,
Yihao Zhang,
Jiakun Zuo,
Yuanyuan Xu,
Xiangan Han,
Zhenhua Luo,
Wei Chen,
Jinfeng Miao

Affiliations

Shaodong Fu: MOE Joint International Research Laboratory of Animal Health and Food Safety, Key Laboratory of Physiology and Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
Chen Wen: MOE Joint International Research Laboratory of Animal Health and Food Safety, Key Laboratory of Physiology and Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
Zhenglei Wang: MOE Joint International Research Laboratory of Animal Health and Food Safety, Key Laboratory of Physiology and Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
Yawei Qiu: MOE Joint International Research Laboratory of Animal Health and Food Safety, Key Laboratory of Physiology and Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
Yihao Zhang: MOE Joint International Research Laboratory of Animal Health and Food Safety, Key Laboratory of Physiology and Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
Jiakun Zuo: Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
Yuanyuan Xu: MOE Joint International Research Laboratory of Animal Health and Food Safety, Key Laboratory of Physiology and Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
Xiangan Han: Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
Zhenhua Luo: School of Water, Energy and Environment, Cranfield University, Cranfield, United Kingdom
Wei Chen: Engineering Laboratory of Tarim Animal Diseases Diagnosis and Control, Xinjiang Production and Construction Crops, College of Animal Science, Tarim University, Tarim, China
Jinfeng Miao: MOE Joint International Research Laboratory of Animal Health and Food Safety, Key Laboratory of Physiology and Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China

DOI: https://doi.org/10.1128/spectrum.02997-22
Journal volume & issue: Vol. 10, no. 6

Abstract

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ABSTRACT Klebsiella pneumoniae is an opportunistic pathogen that causes serious infections in humans and animals. However, the availability of epidemiological information on clinical mastitis due to K. pneumoniae is limited. To acquire new information regarding K. pneumoniae mastitis, data were mined about K. pneumoniae strains on dairy cattle farms (farms A to H) in 7 Chinese provinces in 2021. Hypermucoviscous strains of K. pneumoniae were obtained by the string test. MICs of antimicrobial agents were determined via the broth microdilution method. Ten antimicrobial resistance genes and virulence genes were identified by PCR. The prevalence of K. pneumoniae was 35.91% (65/181), and 100% of the bacteria were sensitive to enrofloxacin. Nine antimicrobial resistance genes and virulence genes were identified and compared among farms. The hypermucoviscous phenotype was present in 94.44% of isolates from farm B, which may be a function of the rmpA virulence gene. Based on these data, the multidrug-resistant strains SD-14 and HB-21 were chosen and sequenced. Genotypes were assayed for K. pneumoniae isolates from different countries and different hosts using multilocus sequence typing (MLST). Ninety-four sequence types (STs) were found, and 6 STs present a risk for spreading in specific regions. Interestingly, ST43 was observed in bovine isolates for the first time. Our study partially reveals the current distribution characteristics of bovine K. pneumoniae in China and may provide a theoretical basis for the prevention and treatment of bovine K. pneumoniae mastitis. IMPORTANCE K. pneumonia is ubiquitous in nature and infects a wide range of hosts, including animals, and humans. It is one of the leading inducements of clinical mastitis (CM) in dairy cows, a prevalent and costly disease that is predominantly associated with bacterial infection. In general, CM caused by Gram-negative bacteria is more difficult to cure than that associated with Gram-positive pathogens, with an average cost per case of 211.03 U.S. dollars (USD) for Gram-negative bacterial infections compared with 133.73 USD for Gram-positive bacterial CM cases. After Escherichia coli, K. pneumoniae is the second most common Gram-negative cause of bovine CM, but it is the most detrimental in terms of decreased milk yield, discarded milk, treatment costs, death, and culling. In view of the economic implications of K. pneumoniae infection in dairy farming, research into population structure and antibiotic resistance is particularly important.

Published in Microbiology Spectrum

ISSN: 2165-0497 (Online)
Publisher: American Society for Microbiology
Country of publisher: United States
LCC subjects: Science: Microbiology
Website: https://journals.asm.org/journal/spectrum

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