Tanya Rossi

Animal Health Laboratory, University of Guelph, Guelph, ON 

AHL Newsletter 2023;27(1):7.

The term One Health, “an integrated, unifying approach to balance and optimize the health of people, animals and the environment”¹, is a relatively new one in medicine; however, the contribution of veterinarians to public health dates back hundreds of years. This contribution has taken many forms, including using comparative physiology and anatomy to further human health, informing policies involving food safety and ecosystem health, and detection of zoonotic pathogens, among others.  AHL participates in many of these initiatives, but our primary contribution is the surveillance and annual reporting of zoonotic pathogens identified at our laboratory (Tables 1 & 2).

Case numbers for most zoonotic pathogens isolated or identified by the AHL in 2022 are relatively unchanged from the previous year.  Blastomyces dermatitidis cases have increased in canines from 5 in 2021 to 13 in 2022.  Avian West Nile virus cases have also increased this year, rising from 11 in 2021 to 26.  Isolation of Methicillin-resistant S. pseudintermedius (MRSP) in canines decreased in 2022, as well as the number of positive serology submission for Borrelia burgdorferi in canines and equines.

The percentage of animals identified as positive for leptospirosis was roughly unchanged in cattle and dogs in 2022, and the total number of submissions tested was about the same as 2021.  The percentage of positive leptospirosis cases increased in equines and swine, and the number of submissions was relatively unchanged in swine and slightly increased in equines.  These are numerator data reliant upon submission biases to the diagnostic laboratory, and cannot be regarded as population prevalence estimates.  They do not take into account vaccination status, as all except horses may be routinely vaccinated for leptospirosis.  Test results submitted under monitoring programs are not included.  Brucella canis results shown are positive on the 2ME-RSAT (Table 1).  AHL

Table 1. Number of cases for selected zoonotic pathogens isolated and/or identified at the AHL, 2022.

Table 2. Leptospira spp. seropositive, IHC-positive, or PCR-positive cases identified at the AHL, 2022

¹ One Health High-Level Expert Panel (OHHLEP), Adisasmito WB, Almuhairi S, Behravesh CB, Bilivogui P, Bukachi SA, et al. (2022) One Health: A new definition for a sustainable and healthy future. PLoS Pathog 18(6): e1010537. https://doi.org/10.1371/journal.ppat.1010537