Human Disease due to Mycobacterium bovis Linked to Free-Ranging Deer in Michigan.

BACKGROUND

A unique enzootic focus of Mycobacterium bovis in free-ranging deer was identified in northern lower Michigan in 1994, with subsequent evidence of transmission to local cattle herds. Between 2002 and 2017, 3 Michigan deer hunters with M. bovis disease were previously reported. We present 4 additional human cases linked to the zoonotic focus in deer, utilizing genomic epidemiology to confirm close molecular associations among human, deer and cattle M. bovis isolates.

METHODS

Identification of human tuberculosis (TB) cases with cultures of M. bovis was provided from the Michigan Department of Health and Human Services (MDHHS) tuberculosis database. Clinical review and interviews focused on risk factors for contact with wildlife and cattle. Whole genome sequences of human isolates were compared with a veterinary library of M. bovis strains to identify those linked to the enzootic focus.

RESULTS

Three confirmed and 1 probable human case with M. bovis disease were identified between 2019 and 2022, including cutaneous disease, 2 severe pulmonary disease cases, and human-to-human transmission. The 3 human isolates had 0-3 single-nucleotide polymorphisms (SNPs) with M. bovis strains circulating in wild deer and domestic cattle in Michigan.

CONCLUSIONS

Spillover of enzootic M. bovis from deer to humans and cattle continues to occur in Michigan. Future studies should examine the routes of transmission and degree of risk to humans through expanded epidemiological surveys. A One Health approach linking human, veterinary and environmental health should address screening for TB infection, public education, and mitigation of transmission.

Informations de copyright

© The Author(s) 2024. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For permissions, please e-mail: [e-mail].

Déclaration de conflit d'intérêts

Potential conflicts of interest. D. M. reports personal payment or honoraria for GSK Speakers Bureau; personal support for attending Olympus Radial EBUS Training. All other authors report no potential conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed.