Coronaviruses are a group of related viruses classified by common properties.
Viruses are infectious agents made up of genetic material enclosed in a protein envelope. Different viruses target different species and various body systems. Different viral diseases can affect:
- respiratory tract
- gastrointestinal tract
- circulatory system
- nervous system
- the skin
- the liver
Coronaviruses got their name from the Latin word corona, meaning crown, which describes their unique appearance.
When viewed under electronic microscopy, coronavirus viral particles look like crowns because they’re covered in club-shaped protein spikes.
Dr. Christopher G. Byers, DVM, DACVECC, DACVIM (SAIM), CVJ
In people, coronaviruses usually cause upper-respiratory illnesses. Canine coronavirus attacks the dogs’ digestive tract.
Further information: Canine Coronavirus Disease
Viruses
Many viruses can infect only certain species and don’t affect others. That is because, in order to cause illness, the virus needs to access the cells. To enter, the virus requires a key. And just like with houses, every lock needs a key that fits. That applies to species as to different types of cells.
That’s why, for example, your dog cannot catch a common cold or flu from you and you won’t get kennel cough from your dog. Dogs can get the flu too but it is caused by a different virus–canine influenza.
Further information: Virus Infections and Hosts
Some viruses, however, found a way around this, such as Rabies.
Canine coronavirus (CCoV)
Canine coronavirus disease is an intestinal infection. It is highly infectious, especially in puppies. It spreads through poop and it doesn’t affect people.
Most dogs can have the virus but no illness. If they do get sick, the symptoms include:
- diarrhea
- lethargy
- loss of appetite
Further information: Canine Coronavirus Disease
Canine respiratory coronavirus (CRCoV)
Canine respiratory coronavirus is part of the kennel cough complex. It is genetically related to the human coronavirus that causes the common cold.
Further information: Canine Respiratory Coronavirus FAQ
Canine influenza
There are two viral strains that can cause flu in dogs. The two identified strains are H3N8 and H3N2. They both have similar symptoms and are different from the seasonal influenza viruses that infect people. There is no evidence that people can get infected with these viruses.
These strains belong to a different class of viruses than coronaviruses.
Further information: Canine Influenza
COVID-19
COVID-19 is a new viral infection that emerged at the end of 2019 in Wuhan province in China. This global pandemic is caused by SARS-CoV-2, a type of coronavirus.
At this time, while spreading like wildfire among the world human population, there is no evidence that it can sicken dogs or that pet dogs can spread the virus. The two Hong Kong dogs that tested positive both belonged to an already infected person. Human to animal transmission of coronaviruses that lead to respiratory disease in people is possible but rarely happened in the past.
However, Dr. Weese of the Ontario Veterinary college doesn’t rule out that dogs and cats could become sick. Which is a different matter from dogs communicating the disease.
An example of this is human influenza in dogs. We can pass the human influenza virus to dogs (it’s rare but it happens), but we consider them “dead-end hosts” – they are infected, but since it’s not their flu virus, they don’t produce enough virus to pass it along to others.
Dr. Scott Weese
Reference: COVID-19: What we don’t know (but that doesn’t mean we can’t do something)
To learn more about COVID-19 and dogs specifically, read COVID-19 and My Dog: Can My Dog Get It and Could They Infect Me?
In closing
Some viruses are zoonotic and can infect multiple species, while others are specific to a species. Dog and humans haven’t shared the same coronavirus infections. To date, there is no evidence the COVID-19 is an exception.
Related articles:
COVID-19 and My Dog: Can My Dog Get It and Could They Infect Me?
Further reading:
Canine Coronavirus Disease
COVID-19 & Your Pet – What You Need to Know!
Websites to keep up with up-to-date information regarding COVID-19 and pets:
Centers for Disease Control and Prevention (CDC)–Animals and Coronavirus Disease (COVID-19)
World Health Organization–Coronavirus disease (COVID-19) advice for the public: Myth busters