Canine coronavirus
Encyclopedia
Canine coronavirus is a virus
of the family Coronaviridae
that causes a highly contagious intestinal disease worldwide in dogs. It was discovered in 1971 in Germany
during an outbreak in sentry dog
s.
of the small intestine
. Intestinal disease may be related to virus-induced apoptosis
(programmed cell death) of cells of the epithelial mucosa of the small intestine. Canine coronavirus was originally thought to cause serious gastrointestinal disease, but now most cases are considered to be very mild or without symptoms. A more serious complication of canine coronavirus occurs when the dog is also infected with canine parvovirus
. Coronavirus infection of the intestinal villi makes the cell
s more susceptible to parvovirus infection. This causes a much more severe disease than either virus can separately. However, fatal intestinal disease associated with canine coronavirus without the presence of canine parvovirus is still occasionally reported. This may be related to the high mutation rate of RNA positive stranded viruses, of which canine coronavirus is one....
is only one to three days. The disease is highly contagious and is spread through the feces
of infected dogs, who usually shed the virus for six to nine days, but sometimes for six months following infection. Symptoms include diarrhea
, vomiting, and anorexia. Diagnosis is through detection of virus particles in the feces. Treatment usually only requires medication for diarrhea, but more severely affected dogs may require intravenous fluids for dehydration
. Fatalities are rare. The virus is destroyed by most available disinfectants. There is a vaccine available (ATCvet code: ), and it is usually given to puppies, who are more susceptible to canine coronavirus, and to dogs that have a high risk of exposure, such as show dogs.
in 2003 from lung samples of dogs and has since been found on the European mainland and in Japan. A serological
study in 2006 has also shown antibodies
to CRCoV to be present in dogs in Canada
and the United States
. However, a retrospective study in Saskatchewan
found that CRCoV may have been present there as far back as 1996.
Virus
A virus is a small infectious agent that can replicate only inside the living cells of organisms. Viruses infect all types of organisms, from animals and plants to bacteria and archaea...
of the family Coronaviridae
Coronaviridae
Coronaviruses are enveloped, single-stranded, positive-sense RNA viruses with club-shaped surface about 120-160 nm in diameter that resemble a “corona”.-Virology:...
that causes a highly contagious intestinal disease worldwide in dogs. It was discovered in 1971 in Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
during an outbreak in sentry dog
Guard dog
A guard dog, an attack dog or watch dog is a dog used to guard against, and watch for, unwanted or unexpected people or animals. The dog is discriminating so that it does not annoy or attack familiar people.-Barking:...
s.
Pathology
The virus invades and replicates in the villiVillus
Intestinal villi are tiny, finger-like projections that protrude from the epithelial lining of the intestinal wall. Each villus is approximately 0.5-1.6 mm in length and has many microvilli , each of which are much smaller than a single villus...
of the small intestine
Small intestine
The small intestine is the part of the gastrointestinal tract following the stomach and followed by the large intestine, and is where much of the digestion and absorption of food takes place. In invertebrates such as worms, the terms "gastrointestinal tract" and "large intestine" are often used to...
. Intestinal disease may be related to virus-induced apoptosis
Apoptosis
Apoptosis is the process of programmed cell death that may occur in multicellular organisms. Biochemical events lead to characteristic cell changes and death. These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, and chromosomal DNA fragmentation...
(programmed cell death) of cells of the epithelial mucosa of the small intestine. Canine coronavirus was originally thought to cause serious gastrointestinal disease, but now most cases are considered to be very mild or without symptoms. A more serious complication of canine coronavirus occurs when the dog is also infected with canine parvovirus
Canine parvovirus
Canine parvovirus type 2 is a contagious virus mainly affecting dogs. The disease is highly contagious and is spread from dog to dog by direct or indirect contact with their feces. It can be especially severe in puppies that are not protected by maternal antibodies or vaccination. It has two...
. Coronavirus infection of the intestinal villi makes the cell
Cell (biology)
The cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is often called the building block of life. The Alberts text discusses how the "cellular building blocks" move to shape developing embryos....
s more susceptible to parvovirus infection. This causes a much more severe disease than either virus can separately. However, fatal intestinal disease associated with canine coronavirus without the presence of canine parvovirus is still occasionally reported. This may be related to the high mutation rate of RNA positive stranded viruses, of which canine coronavirus is one....
Symptoms, diagnosis, treatment, and control
The incubation periodIncubation period
Incubation period is the time elapsed between exposure to a pathogenic organism, a chemical or radiation, and when symptoms and signs are first apparent...
is only one to three days. The disease is highly contagious and is spread through the feces
Feces
Feces, faeces, or fæces is a waste product from an animal's digestive tract expelled through the anus or cloaca during defecation.-Etymology:...
of infected dogs, who usually shed the virus for six to nine days, but sometimes for six months following infection. Symptoms include diarrhea
Diarrhea
Diarrhea , also spelled diarrhoea, is the condition of having three or more loose or liquid bowel movements per day. It is a common cause of death in developing countries and the second most common cause of infant deaths worldwide. The loss of fluids through diarrhea can cause dehydration and...
, vomiting, and anorexia. Diagnosis is through detection of virus particles in the feces. Treatment usually only requires medication for diarrhea, but more severely affected dogs may require intravenous fluids for dehydration
Dehydration
In physiology and medicine, dehydration is defined as the excessive loss of body fluid. It is literally the removal of water from an object; however, in physiological terms, it entails a deficiency of fluid within an organism...
. Fatalities are rare. The virus is destroyed by most available disinfectants. There is a vaccine available (ATCvet code: ), and it is usually given to puppies, who are more susceptible to canine coronavirus, and to dogs that have a high risk of exposure, such as show dogs.
Canine respiratory coronavirus
Recently, a second type of canine coronavirus (Group II) has been shown to cause respiratory disease in dogs. Known as canine respiratory coronavirus (CRCoV) and found to be similar to strain OC43 of bovine and human coronaviruses, it was first isolated in the United KingdomUnited Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
in 2003 from lung samples of dogs and has since been found on the European mainland and in Japan. A serological
Serology
Serology is the scientific study of blood serum and other bodily fluids. In practice, the term usually refers to the diagnostic identification of antibodies in the serum...
study in 2006 has also shown antibodies
Antibody
An antibody, also known as an immunoglobulin, is a large Y-shaped protein used by the immune system to identify and neutralize foreign objects such as bacteria and viruses. The antibody recognizes a unique part of the foreign target, termed an antigen...
to CRCoV to be present in dogs in Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
and the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. However, a retrospective study in Saskatchewan
Saskatchewan
Saskatchewan is a prairie province in Canada, which has an area of . Saskatchewan is bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, and on the south by the U.S. states of Montana and North Dakota....
found that CRCoV may have been present there as far back as 1996.