Detection of Brucella spp. during a serosurvey of pig‐hunting and regional pet dogs in eastern Australia

Abstract

Brucellosis is a zoonotic disease with worldwide distribution. Brucella suis serotype 1 is thought to be maintained in the Australian feral pig population, with disease prevalence higher in Queensland (Qld) than New South Wales (NSW). Pig hunting is a popular recreational activity in rural Qld and NSW, with feral pigs in these states thought to carry B. suis. Brucellosis associated with B. suis has been diagnosed in dogs engaged in pig hunting in some of these areas. A total of 431 dogs from northern Qld and north‐west NSW were recruited. Two distinct cohorts of clinically healthy dogs were tested – (1) 96 dogs from central, north and far north Queensland actively engaged in pig‐hunting and (2) 335 dogs from rural and remote north‐west NSW that were primarily companion (non‐pig hunting) animals. Serum samples were tested for antibodies to Brucella spp. using the Rose Bengal test (RBT) test followed by complement fixation testing (CFT) for RBT‐positive samples. A subset of samples was retested using RBT and CFT. Seven dogs were considered seropositive for B. suis from Qld and remote NSW, including 4/96 (4.2%; 95% CI 3.5% to 4.3%) from the pig‐hunting cohort and 3/335 (0.9%) from the regional pet dog cohort. The use of RBT and CFT in dogs to detect anti‐Brucella antibodies requires validation. Veterinarians treating pig‐hunting dogs and physicians treating pig hunters in central, north and far north Qld need to be aware of the zoonotic risk posed by B. suis to these groups.

Presence of Foodborne Bacteria in Wild Boar and Wild Boar Meat—A Literature Survey for the Period 2012–2022

“…In two cases, neurological disorders [ 18 , 23 ] were reported, and in one case, arterial and venous thromboses were reported [ 20 ], which are otherwise rarely observed [ 24 ]. Similarly, dogs frequently in contact with wild boar are at risk of seropositivity to Brucella [ 25 , 26 , 27 ].…”

Molecular Investigations of Two First Brucella suis Biovar 2 Infections Cases in French Dogs

“…A recent seroprevalence study, for example, found that nearly one in 10 (9.3%) dogs in eastern Australia, being exposed to feral pigs or their meat products, are seropositive to smooth Brucella spp. (including B. suis ) [ 44 , 45 , 46 ]. In Australia, B. suis biovar 1 is responsible for canine infections.…”

Brucella suisin three dogs: presentation, diagnosis and clinical management

“…Dogs are not the preferred host for B. suis and the pathophysiology, transmission risk and potential for treatment in dogs are poorly understood. In the last decade, there has been an increase in the detection of B. suis in dogs, particularly in Australia and the United States 4–8 . Our recent seroprevalence study, for example, found that nearly one in 10 (9.3%) dogs in eastern Australia that are exposed to feral pigs or their meat products are seropositive for B. suis 9 …”

“…In the last decade, there has been an increase in the detection of B. suis in dogs, particularly in Australia and the United States. [4][5][6][7][8] Our recent seroprevalence study, for example, found that nearly one in 10 (9.3%) dogs in eastern Australia that are exposed to feral pigs or their meat products are seropositive for B. suis. 9 In Australia, dogs and humans become infected with B. suis following contact with body fluids and/or tissues from infected feral pigs, making hunting and butchering of feral pigs and feeding of uncooked pig meat the most common risk factors for infection.…”