Kennel Cough: Etiology and Symptoms

Kennel Cough

• Results from inflammation of the upper airways.
• It is a mild, self-limiting disease that may progress to bronchopneumonia in puppies or chronic bronchitis in debilitated adult or aged dogs.
• Spreads rapidly among susceptible dogs housed in close confinement like vet hospitals, doggy daycares, boarding facilities, and kennels.
• Dogs of all ages can be affected, but puppies are more prone to severe disease.

Etiology of Kennel Cough

• Bordetella bronchiseptica (bacteria)
• Canine parainfluenza virus (CPIV)
• Canine adenovirus 1 (CAV-1)
• Canine adenovirus 2 (CAV-2)
• Canine influenza virus
• Canine distemper virus
• Canine reoviruses (types 1, 2, and 3)
• Canine herpesvirus (very young puppies)
• Mycoplasma canis (a single-cell organism that is neither virus nor bacterium)
• A classical combination for uncomplicated kennel cough is infection with parainfluenza or adenovirus type 2 in combination with Bordetella bronchiseptica.
• Infections involving distemper virus, mycoplasma species or canine influenza are more likely to progress to pneumonia.
• Pneumonia can readily result in any dog or puppy that is sufficiently young, stressed, or debilitated.

Clinical Findings of Kennel Cough

• Main clinical sign is a cough that sounds like a “goose honk"
• The cough may be followed by retching and gagging.
• Cough is easily induced by gentle palpation of the larynx or trachea.
• Body temperature and WBC counts usually remain normal.
• Severe signs include fever, purulent nasal discharge, depression, anorexia, and a productive cough which indicate bronchopneumonia.
• Stress and improper nutrition can cause a relapse during convalescence.
• Uncomplicated cases have lots of coughing, without fever or listlessness.
• Appetite loss, labored breathing, and reduced activity can indicate progression to pneumonia.

Diagnosis of Kennel Cough

• Should be suspected whenever the characteristic cough suddenly develops 5-10 days after exposure to other susceptible or affected dogs.
• Severity usually diminishes during the first 5 days, but the disease persists for 10-20 days.
• Tracheal trauma secondary to intubation may produce a similar but generally less severe syndrome.
• Thoracic radiographs are essential to determine the severity of disease and to exclude other cause of cough.
• Thoracic radiographs are often normal in dogs with a cough only.
• Evidence of alveolar disease is apparent if the disease has progressed to pneumonia.
• Nasopharyngeal or tracheal swabs may be taken for PCR testing to evaluate the cause of the clinical signs.

Treatment of Kennel Cough

• Appropriate management practices, including good nutrition, hygiene, and nursing care is important.
• Cough suppressants containing codeine derivatives
• Hydrocodone at 0.25 mg/kg, PO, bid qid
• Butorphanol at 0.05 – 0.1 mg/kg, PO or SC, bid qid
• Antibiotics include:
• cephalosporins
• quinolones
• chloramphenicol
• tetracycline
• Recommended antibiotics:
• Amoxicillin/clavulanic acid 12–25 mg/kg, PO, every 12 hours
• Trimethoprim-sulfa drugs 15–30 mg/kg, PO, every 12 hours (schirmer tear test should be performed before starting medications)
• Enrofloxacin 10 mg/kg, PO, every 24 hours
• Doxycycline or minocycline 5–10 mg/kg, PO, every 12 hours for 7–14 days
• When needed, the antibiotic should be selected by culture and sensitivity tests of specimens collected by tracheal wash or bronchoscopy.
• Antibiotics given PO or IM may not significantly reduce the numbers of B bronchiseptica in the distal trachea or major bronchi.
• Severely affected dogs that are not responsive to parenteral antibiotics, kanamycin sulfate (250 mg) or gentamicin sulfate (50 mg) diluted in 3 mL of saline may be administered by aerosolization bid for 3 days.
• Endotracheal injection of antibiotics is a possible alternative to aerosolization.

Prevention of Kennel Cough

• Dogs should be immunized with modified-live virus vaccines against Distemper, Parainfluenza, and CAV-2, which also provides protection against CAV-1.
• Commercial products frequently combine these agents and may include modified-live Parvovirus and Leptospiral antigens.
• An initial vaccination should be given at 6–8 weeks and repeated twice at 3- to 4-week intervals until the dog is 14-16 weeks old.
• Revaccination should be performed annually.
• When the risk of B bronchiseptica infection is significant, a live, avirulent, intranasal vaccine or parenteral products containing subunit bacterial extracts should be used.
• A combination of an avirulent B bronchiseptica and a modified-live parainfluenza vaccine is available for intranasal use.
• One inoculation is administered to puppies >3 wk old.
• Nasal Vaccine can be given as early as 3 weeks of age, and immunity generally lasts 12 to 13 months.
• The advantage is local immunity is stimulated right at the site where the natural infection would try to take hold.
• It takes four days to generate a solid immune response after intranasal vaccination.
• Nasal vaccine for Bordetella generally also include a vaccine against parainfluenza virus and some also include a vaccine against adenovirus type 2.
• An oral vaccine is available for Bordetella bronchiseptica that is easier to give to puppies as young as eight weeks of age. The vaccine is given annually.
• Injectable vaccination is a good choice for aggressive dogs and puppies. Injectable vaccination provides good systemic immunity as long as two doses are given (approximately one month apart) after age 4 months. Boosters are generally given annually.

Canine Corona Virus (CCoV)

• CCoV is an enteric viral infection, primarily affecting the small intestine of dogs, causing enteritis and associated symptoms like diarrhea and vomiting.
• It is classified under Alphacoronavirus, distinct from human coronaviruses such as SARS-CoV-2.
• CCoV is significant in veterinary medicine due to its high contagiousness in environments with high dog density.
• Early diagnosis and prevention are essential for reducing morbidity, especially in puppies and immunocompromised dogs.
• CCoV causes gastrointestinal disease, while SARS-CoV-2 affects humans primarily through the respiratory system.
• CCoV is restricted to dogs and does not present a zoonotic risk.
• CCoV primarily infects dogs because it targets cells in a dog's digestive system, particularly in the intestines.
• SARS-CoV-2 infects human cells, specifically targeting the respiratory system (lungs), using a receptor found mainly on human cells called ACE2.
• Both CCoV and SARS-CoV-2 belong to the coronavirus family, which includes viruses that cause respiratory or intestinal diseases in different animals, and each one is adapted to infect a specific species.
• CCoV is a canine-specific strain and is not capable of infecting humans.
• The word “coronavirus" refers to the virus family and includes many viruses that share a similar structure under a microscope (they have a “crown” of spike proteins).

Etiology and Pathogenesis of CCoV

• Canine Coronavirus (CCoV, Alphacoronavirus) is the causative agent.
• CCoV is an RNA virus in the Alphacoronavirus genus, which specifically targets the intestinal epithelium in dogs, resulting in enteritis.
• CCoV is transmitted primarily through the fecal-oral route through contaminated feces or coming into contact with contaminated surfaces in environments like kennels or shelters.
• Upon entry, CCoV targets the enterocytes in the small intestine, leading to inflammation, malabsorption of nutrients, and fluid loss which results in diarrhea, vomiting, and dehydration.

Epidemiology of CCoV

• CCoV is common in environments with high dog density and puppies are particularly vulnerable due to their immature immune systems.
• Puppies under 6 months old are at a higher risk of severe infections.
• Dogs with weakened immune systems are more susceptible.
• Overcrowded kennels, inadequate sanitation, and poor hygiene practices increase the likelihood of CCoV transmission.

Clinical Signs and Symptoms of CCoV

• Common symptoms include watery diarrhea (often foul-smelling), vomiting, lethargy, and anorexia.
• Puppies often have more severe symptoms and adult dogs may experience milder symptoms, but can still become severely dehydrated.
• Co-infection with Canine Parvovirus (CPV) or Giardia can complicate the clinical course, leading to more severe gastrointestinal distress and a higher risk of secondary bacterial infections due to immunosuppression.
• The incubation period is about 1-4 days after exposure.
• The peak of clinical signs usually occurs within 2-4 days after the onset of symptoms.

Diagnosis of CCoV

• A detailed history of exposure and clinical signs can help guide diagnosis.
• Gold standard is PCR testing
• ELISA and Serology can detect antibodies, but it may not distinguish between past and active infections
• Fecal Examination to rule out Giardia, bacterial infections, and Canine Parvovirus.
• Distinguishing CCoV causes bloody diarrhea which is more severe

Treatment and Management of CCoV

• Use Lactated Ringer's Solution (LRS) or Normosol-R to rehydrate and restore electrolyte balance.
• Oral Rehydration by offering Mondex
• Electrolyte Correction by supplementing with Potassium Chloride for potassium deficiency and saline for sodium correction.
• Offer Hill's Prescription Diet i/d or Royal Canin Gastrointestinal Diet, which are easily digestible and provide small, frequent meals to avoid overwhelming the stomach.
• Cerenia (Maropitant citrate) or Metoclopramide (Reglan) can be used as antiemetics.
• Use Loperamide (Imodium) or Diphenoxylate (Lomotil) as anti-diarrheals under veterinary supervision.
• Ener-G can be used to restore healthy gut bacteria.
• Doxycycline (Pawpy Dox 20) may be prescribed for secondary infections.
• Immuno PetShield may contain antioxidants, vitamins, minerals, and herbal extracts and boost immune function and overall health.
• Anti-diarrheal medications (e.g., Loperamide) and antiemetics (e.g., Maropitant, Ondansetron) help control symptoms and improve comfort.

Prevention and Control of CCoV

• Combination Vaccine (Quantum Dog DA2PPL) protects against Canine Distemper Virus (CDV), Canine Adenovirus Type 1 (CAV-1), Canine Adenovirus Type 2 (CAV-2), Canine Parvovirus (CPV), Canine Parainfluenza Virus (CPiV), Leptospirosis.
• A separate vaccine specifically for Canine Coronavirus (killed virus) that provides immunity against common gastrointestinal issues.
• Biosecurity measures in kennels and breeding facilities can be used by isolating infected dogs, disinfecting surfaces, and limiting contact between dogs in overcrowded environments.
• Maintain clean facilities and regularly disinfect kennels, food/water bowls, and bedding.

Rabies

• Rabies is a fatal encephalitis of all warm-blooded mammals that manifests mainly in either a furious or dumb (paralytic) form.
• Rabies is an acute, progressive viral encephalomyelitis that principally affects carnivores and bats, although any mammal can be affected.
• The disease is fatal once clinical signs appear.
• Rabies is a preventable viral disease most often transmitted through the bite of a rabid animal.
• The rabies virus infects the Central Nervous System (CNS) of mammals, ultimately causing disease in the brain and death.
• Rabies is caused by lyssaviruses in the Rhabdovirus family and is usually confined to one major reservoir species in a given geographic area, although spillover to other species is common.
• Transmission occurs via introduction of virus-laden saliva into tissues, usually by the bite of rabid animal.
• Virus from saliva, salivary glands, or the brain can cause infection by entering the body through fresh wounds or intact mucus membrane.
• Most rabies cases in dogs develop within 21-80 days after exposure with the virus traveling via peripheral nerves to the spinal cord and ascending to the brain.
• Virus travels via peripheral nerves to the salivary glands after reaching the brain.
• The most reliable signs are characterized by acute behavioral changes and unexplained progressive paralysis.
• Animals with rabies usually exhibit typical signs of CNS disturbance and prodromal lasts.
• The most reliable signs are Acute Behavioral changes and unexplained Progressive paralysis:
• Acute behavioral changes
• Anorexia
• Signs of nervousness
• Irritability
• Hyperexcitability (including priapism)
• Ataxia, altered phonation and changes in temperament apparent.
• In the furious form animals become irritable with slight provocation and will aggressively use claws and teeth
• Posture and expression is one of alertness and anxiety, with pupils dilated.
• Animals will lose caution and fear of people and other animals. Noise may invite attack.
• Rabid dogs may chew the wire and break their teeth attempting to bite.
• Muscular incoordination and seizures are common.
• During the paralytic or end stage the paralysis progresses rapidly to all parts of the body, and coma and death follow in a few hours.
• Rabies is manifested by Ataxia and paralysis of the throat and masseter muscles, often with profuse salivation and the inability to swallow, and dropping of the lower jaw is common in dogs.

Diagnosis of Rabies

• Immunofluorescence microscopy on fresh brain tissue allows visual observation of a specific antigen antibody reaction.
• Brain tissues examined must include medulla oblongata and cerebellum and are preserved by refrigeration with wet ices or cold packs.
• Virus isolation by tissue culture techniques using mouse neuroblastoma cells may be used for confirmation of indeterminate fluorescent antibody results, but is no longer in common use in the USA.
• Rabies has the highest case fatality of any infectious disease and risk of rabies virus transmission should be evaluated carefully.
• Dogs are the highest-risk breed

Canine Ehrlichiosis

• In dogs, ehrlichiosis is caused by three Ehrlichial species, Ehrlichia canis, E. ewingii, and E. chaffeensis, with E. canis being most potent.
• it is caused by a brown dog tick, Rhipicephalus sanguineus infected with the bacteria, Ehrlichia canis.
• German Shepherds, Doberman Pinschers, Belgium Malinois, and Siberian Huskies appear to get a more severe form of this disease compared to other dogs.
• Dogs do not directly transmit the disease to each other.
• It's maintained by a cycle of transmission between ticks and dogs.
• The three phases are:
• Acute (weeks)
• Subclinical (months to years)
• Chronic/ clinical
• Multiplies within circulating mononuclear cells of Mononuclear phagocytic tissues of the liver, spleen, and lymph nodes.
• Infected cells are transported in the blood to other tissues, particularly meninges, lung, and kidney, where they attach to the vascular endothelium, causing vasculitis and infection of the subendothelial tissue.

Features of the Acute and Subclinical Phases of Canine Ehrlichiosis

• Acute Phase lasts 2-4 weeks involving, Fever, Respiratory distress, Swollen lymph nodes, Weight loss, Bleeding disorders and Neurological disturbances
• Subclinical Phase is present but the disease has no clinical signs however it can noticed in prolonged bleeding from the injection site after taking a blood sample.
• During the clinical or chronic phase the organism is not eliminated by the immune system causing Lameness, Swollen limbs, Neurological problems, Bleeding episodes, Anemia, and Eye problems.
• Diagnosis is done via Enzyme-linked immunosorbent assay (ELISA) or DNA/PCR and through a Complete blood cell count and serum blood chemistry.
• Urinalysis to determine if the disease is affecting the kidney.
• Doxycycline or Tetracycline are effective for treatment

Prevention of Canine Ehrlichiosis

• Most tick bites can beprevented through monthly flea and tick preventative care and there is currently no vaccine available
• Dogs with chronic E. canis infection is guarded as this stage can be fatal.

Canine Babesiosis

• Is a tick-borne disease caused by protozoan parasites of the Babesia genus causing severe anemia, organ damage, and death in dogs.
• Certain breeds, such as Greyhounds and Pit Bulls, appear to be more susceptible, and factors like age, immune status, and concurrent infections may influence disease severity.
• Common species affecting dogs include Babesia canis, Babesia gibsoni, Babesia vogeli and Babesia conradae
• Are transmitted primarily through tick bites, particularly by the Rhipicephalus sanguineus (brown dog tick) and Dermacentor species.
• Babesia organisms infect & multiply within red blood cells this lead to Hemolysis Immune and Systemic Inflammation and Organ Damage.

Forms of Canine Babesiosis

• Acute Form
• Characterized by Fever, Pale or yellow (icteric) mucous membranes, Lethargy and weakness, Enlarged lymph nodes and spleen, Dark-colored urine (hemoglobinuria) as well as Vomiting and anorexia
• Chronic Form
• Characterized by Intermittent fever, Weight loss and Mild anemia

Diagnosis, Treatment and Prevention of Canine Babesiosis

• Diagnosis through Blood smear examination,PCR, Serology and also a complete blood count and Biochemistry profile
• Treatment with Imidocarb dipropionate, Atovaquone and Azithromycin and Diminazene aceturate
• Also provide Supportive Care and Anti-inflammatory drugs
• Prevent via Tick Control through regular use of tick preventatives such as spot-on treatments as well as Environmental Management through cleaning of kennels with dogs previously infected.

Lyme Disease

• Lyme disease is caused by the Borrelia burgdorferi bacteria and carried on by various specifies that include the Deer Tick.
• the bacteria can travel to different parts of the body and cause problems in dog's organs and joints, as well as overall illness.
• Can be transmitted from the tick in up to 2 days and it's important to monitor the dogs for ticks

Treatment of Lyme Disease

• A 4-to 6-week course of antibiotics for dogs will be prescribed and many owners see improvement within a few days.
• A second round of antibiotics is often required, as the infection may persist through the first round of treatment.
• Severe cases of Lyme disease will require additional therapy to treat affected kidneys, heart, or nerves, along with supportive care like intravenous fluids.
• Re-checking blood work is recommended six months after completing antibiotic therapy to determine if treatment has been successful.