Identification of Novel Strains of <i>Pasteurella multocida</i>, an Important Pathogen of <i>Marmota himalayana</i> Found on China's Qinghai-Tibet Plateau

Three novel capsule type strains of the highly pathogenic bacterium, <i>Pasteurella multocida</i>, were first isolated from the tissues&nbsp;of <i>Marmota Himalayanas</i> that had died of natural causes on China’s Qinghai-Tibet plateau. Two strains were identified as subspecies <i>Multocida</i> and one was <i>Septica</i>. Whole genome phylogeny was constructed from 3,262&nbsp;core SNPs and demonstrated a cluster that was distinct from other strains. GS2020-X2, AKS2021-HT3 and GS2020-R1 were L3 type, and AKS2021-HT67 may represent a new lipolysaccharide genotype. Infected animals had sepsis and systemic organ lesions. Ten single clones were able to kill experimental mice within 24 hours. Serum IL-12P70, IL-6, TNF-alpha and IL-10 levels were elevated at different time points (P &lt;0.05) showing evidence of a cytokine storm.<i> P. multocida</i> represents an important pathogen of <i>Marmota himalayana</i> that die of natural causes. Contact with <i>Marmota himalayana</i> may serve as a source of <i>P. multocida</i> infection in humans.<br><br>Funding Information: This work was supported by the National Sci-Tech Key Project (grant nos. 2018ZX10713-003-002 and 2018ZX10713-001-002).<br><br>Declaration of Interests: The authors declare no competing interests.<br><br>Ethics Approval Statement: All methods were carried out in accordance with the protocols for laboratory animal use and proper care and approved by the Animal Care and Use Committee of China CDC.<br>