An illness of the nose, throat, and sinus area of felids which is very similar to the common cold in humans: Olive's Egyptian cat was ill and it was diagnosed by the veterinarian as having a feline upper respiratory infection, a dangerous condition but treatable with medications.

In tabbies, these feline upper respiratory infections, which are common and very contagious, are more common in areas associated with overcrowding and poor sanitation, for example in catteries and rescue shelters and also in outdoor feral cat populations (a feral cat or other animal is one that lives in a wild state but was once kept as a pet or lived on a farm).

Several organisms, both bacterial and viral, can cause the feline upper respiratory infection and the two primary viruses usually are feline herpesvirus-1 (FHV) and feline calicivirus (FCV).

Feline Chlamydia, a bacterial infection, can also result in feline upper respiratory tract infections, as well as other organisms which are spread from felid to kitty through eye, nasal, and oral secretions.