Canine infectious respiratory disease complex (CIRDC) worldwide: A review of epidemiology and distribution

Canine infectious respiratory disease complex (CIRDC), also known as kennel cough, is a highly contagious multifactorial syndrome in dogs, caused by both bacterial and viral pathogens. Disease is predominantly observed in environments with high canine density, such as shelters. Although CIRDC is typically presented with mild to moderate clinical manifestations, in puppies and immunocompromised dogs, CIRDC can lead to severe clinical manifestations. The present review provides a systematic analysis of 68 peer-reviewed publications and reports from 1965 to 2025, to examine worldwide prevalence rates and geographic distribution of pathogens associated with CIRDC. Data were extracted from five major scientific databases (PubMed, Scopus, Google Scholar, ScienceDirect, and Web of Science), focusing on the frequency of pathogens, their geographical distributions and detection methodologies. The most frequently identified bacterial agents are Bordetella bronciseptica and Mycoplasma spp., and among viral agents, canine parainfluenza virus and canine respiratory coronavirus. Canine influenza virus is rarely detected in Europe, but has been detected in shelter dogs in the U.S. Notably, CIRDC is characterized by a high co-infection rate. The review highlights the importance of updated diagnostics, targeted vaccination strategies and enhanced surveillance systems. Data from Serbia are scarce, underscoring the urgent need for national prevalence studies and improved vaccine coverage.