BACKGROUND: Toxocara canis is a zoonotic disease that commonly infects canids. Mammals and birds are sometimes infected with this disease as paratenic hosts. It can also cause accidental infection in humans. The increase in the number of stray dogs, the expansion of urban gardens, and the proximity of dogs to humans increase the risk of human infection with Toxocara canis.OBJECTIVES: This study aims to determine the prevalence of Toxocara canis infection in dogs and foxes in Zanjan province, Iran.METHODS: A total of 484 fecal samples of stray dogs (n=355), rescue dogs (n=49), guard dogs (n=50), and foxes (n=30) in Zanjan were randomly collected from June 2021 to February 2022. The microscopic examination was done following formalin-ethyl acetate sedimentation procedures. Finally, the PCR method was used to confirm the presence of Toxocara canis in positive samples.RESULTS: Microscopic study revealed that, out of 484 samples, 21 (4.3%) were positive for Toxocara/ Toxascaris eggs. Between these positive samples of dogs and foxes, only 6 samples from dog feces were confirmed as a Toxocara canis infection by the PCR method.CONCLUSIONS: There is an increase in the prevalence of Toxocara canis infection in stray dogs in Zanjan, Iran. Given the presence of dogs in parks and residential areas, there is a risk of human infection with Toxocara canis, emphasizing the importance of adhering to treatment and prevention protocols in dealing with stray dogs.

BACKGROUND: The bacterium Capnocytophaga canimorsus is a relatively newly recognized gram-negative, facultative, slow-growing bacillus that forms part of the normal oral flora of dogs and cats. Considering the pathogenicity of this bacterium in humans, determining its prevalence is very important for public health as well as the health of dog owners.OBJECTIVES: This study aims to investigate the prevalence of Capnocytophaga canimorsus in the normal oral flora of healthy dogs.METHODS: After taking samples from the saliva of 32 healthy dogs without oral, dental or digestive diseases at different ages, breeds, and sexes, they were placed in a test tube containing 10 mL of sterile peptone water with sterile plastic brushes, and immediately sent to the bacteriology laboratory under sterile conditions. The samples were cultured on a chocolate agar medium containing 5 % defibrinated sheep blood. Then, all the samples were kept in a greenhouse for 48 hours at a temperature of 37 °C and under anaerobic conditions. Using a loop, the grown pink colonies were isolated and to confirm the identification of the isolates, polymerase chain reaction (PCR) test was used in three main steps: Gene extraction, PCR reaction, and electrophoresis.RESULTS: Out of 32 saliva samples, four positive cases of Capnocytophaga canimorsus bacteria were identified by PCR diagnostic method.CONCLUSIONS: Given that Capnocytophaga canimorsus bacterium is present in the oral flora of healthy ​​dogs, dog owners should have sufficient and favorable knowledge about this bacterium and related diseases. The PCR method can be used to detect this bacterium.