Atypical canine infectious respiratory disease complex ( aCIRDC ) is a proposed novel respiratory disease in dogs [1] of unknown cause. It has been recorded in 19 US states, with more cases on the West Coast. [ citation needed ]
It has also been referred to as respiratory syndrome of unknown aetiology in dogs and as canine respiratory disease of unknown origin. [2]
It was first described in summer 2023 as a cluster of 200 cases around Portland, Oregon. [3]
Symptoms include a cough, fever, lethargy, sneezing and watery eyes. In some cases, the illness proceeds to death. [1] Cases tend to fit three clinical syndromes: chronic mild/moderate tracheobronchitis of prolonged duration (6+ weeks), [4] with coughing, sneezing, and watery eyes; chronic pneumonia that is minimally responsive to antimicrobials, possibly including dyspnea; and, rarely, acute pneumonia that rapidly becomes severe and can lead to death. [5] [6] Most cases are self-limiting and respond well to supportive care. [7] Antibiotics may be indicated. [6]
Diagnosis should rule out known forms of canine infectious respiratory disease complex (CIRDC; also known as kennel cough). aCIRDC does not respond to regular treatment protocols for CIRCD and the course of the disease is longer and more severe. [8]
There is no evidence that it can spread to humans. [ citation needed ]
The cause is currently unknown. [ citation needed ]
The Veterinary Diagnostic Laboratory at the University of New Hampshire have put forth a possible bacterium as the cause. [5] They have tentatively identified this as IOLA KY405 , [9] which was previously identified in humans in 2021. [10] This is similar to Mycoplasma in lacking a cell wall and having a small genome. [9]
However, other vets have suggested that this might just represent a peak in CIRDC cases and not involve any new pathogens. This could be due to changes in human behaviour following the end of COVID-19 lockdowns and other COVID-19-related disruption to veterinary care ( e.g. frequency of vaccination), as well as to the general increase in dog numbers in the US. [11] [6]