Epidemiological Surveillance of Respiratory Diseases in Urban Stray Cats in Shanghai.

Urban stray cats are cats without owners that survive in the wild for extended periods of time. They are one of the most common stray animals in cities, and as such, monitoring the pathogens carried by urban stray cats is an important component of urban epidemiological surveillance. In order to understand the prevalence of respiratory diseases in urban stray cats in Shanghai and provide scientific evidence for the development of targeted prevention and control strategies for respiratory diseases in stray cats, we collected 374 ocular, nasal, and oropharyngeal swabs from urban stray cats in Shanghai from January 2022 to December 2022. After RNA extraction, we used real-time PCR to detect six respiratory pathogens, including influenza A virus, feline calicivirus, feline herpesvirus type 1, , , and . The results showed that among the 374 samples, 146 tested positive, with a positivity rate of 39.04%. The highest positivity rate was observed for at 18.72% (70/374), followed by at 11.76% (44/374), feline calicivirus at 3.74% (14/374), feline herpesvirus 1 at 3.48% (13/374), at 1.34% (5/374), and influenza A virus was not detected. The highest positivity rate for was in Minhang District at 31.94% (23/72), while and had the highest positivity rates in Jiading District at 23.53% (8/34) and 5.88% (2/34), respectively. The highest positivity rates for feline calicivirus and feline herpesvirus 1 were both observed in Qingpu District, at 14.46% (12/83) and 9.64% (8/83), respectively. A total of 36 samples showed mixed infections with two or more pathogens, with being involved in 32 of these mixed infections, with the highest number of mixed infections being with at 25 samples. Respiratory pathogen positivity was detected throughout the year, with peak detection rates in summer and winter. The positivity rates of cat respiratory pathogens in different seasons showed statistical differences (χ = 27.73, < 0.01). There was no statistical difference in the positivity rates of respiratory pathogens between cats of different genders (χ = 0.92, > 0.05). The positivity rates of respiratory pathogens in cats of different age groups showed statistical differences (χ = 44.41, < 0.01). and were the main pathogens causing respiratory infections in stray cats, with showing a much higher positivity rate than other respiratory pathogens and often co-infecting with and feline calicivirus. The positivity rate of was high in summer, autumn, and winter, with no statistical difference between seasons. These results indicate a serious overall prevalence of respiratory pathogens in urban stray cats in the Shanghai area, showing seasonal trends and mixed infections with other pathogens. These findings suggest the need for comprehensive prevention and control measures to address respiratory pathogen infections in urban stray cats in the Shanghai area.