In most cases, symptoms of contagious ecthyma typically develop 2 to 3 days after initial contact with the infected object. Signs begin as small raised papules, sores, and blisters found on the nose, ears, lips, and eyelids.
If you notice these bumps developing on your dog and take him to the veterinarian, she will first begin by collecting a history from you. When symptoms are in the small red bump phase, it can be difficult to identify what exactly they are from. These bumps can be caused by an allergy, either internally or externally, can be caused by excessive exposure to heat, can be caused by something he touched, and many other sources. If you explain to the veterinarian the environment your dog has been in the last few days, or mention possible exposure to animals who may carry the virus, it will help her to identify the source. Also, if you do have other animals on your property that are sick, be sure to mention it. It may or may not be a part of daily life for you to interact with other animals, but it may be the key to a proper diagnosis for your dog.
The veterinarian may want to take a skin scraping to rule out other possible causes of the papules. Skin bacteria or parasites can also cause these symptoms. By collecting a skin scraping, she will be able to take a look at it under the microscope to check for a cause other than the virus.