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

Document Type

Article

Publication Date

3-20-2024

Publication Title

Clinical infectious diseases

Abstract

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 three Michigan deer hunters with M. bovis disease were previously reported. We present four 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 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 one probable human case with M. bovis disease were identified between 2019 and 2022, including cutaneous disease, two severe pulmonary disease cases, and human-to-human transmission. The 3 human isolates had 0-3 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.

Volume

78

Issue

3

First Page

637

Last Page

645

DOI

10.1093/cid/ciae009

ISSN

1537-6591

PubMed ID

38207126

Link to Full Text

Share

COinS