Canine Parainfluenza Virus Infection

Canine parainfluenza virus (CPIV) is a highly contagious respiratory virus that primarily affects dogs. It is one of the major pathogens associated with kennel cough, a common respiratory disease in canines. CPIV endangers the health of companion animals, and also seriously endangers the canine breeding industry. BioVenic, as an expert in canine diseases, has a comprehensive understanding of CPIV. We are committed to providing customers with detailed CPIV information, as well as advanced diagnostic tools and methods, vaccines, etc., to help reduce the negative impact of the virus.

Etiology

CPIV belongs to the Paramyxoviridae family, specifically the Rubulavirus genus. The diameter of CPIV is between 80-200 nm, and most of them are round and enveloped. CPIV primarily affects the respiratory system, causing inflammation and respiratory symptoms.

Fig. 1 Schematic diagram of the structure of CPIV particles.¹

Geographical Distribution

In 1967, Binn successfully isolated CPIV from dogs with respiratory diseases using canine kidney cells (MDCK) for the first time. CPIV is responsible for causing canine infectious respiratory disease (CIRD), commonly known as kennel cough (KC) or canine infectious tracheobronchitis (CITB).

Presently, CPIV infection is widespread globally, occurring in regions where canines are raised, particularly in areas with concentrated dog populations. The virus poses a significant threat to canine health and well-being, necessitating ongoing efforts for prevention, early detection, and effective management.

Susceptible Animals

CPIV has the potential to cause disease in a variety of animals, including dogs, mice, guinea pigs, hamsters, tigers, mink, cattle, rabbits, monkeys, red pandas, sheep, and horses. Dogs, however, are the natural hosts for CPIV.

In large-scale breeding facilities, factors such as high breeding density, humid environments, poor sanitation, individual immune variations, and group immune insufficiency contribute significantly to the prevalence of this disease. In free-range areas, insufficient immunity from parainfluenza vaccines, changes in weather, and a substantial influx of pathogens are the primary factors leading to the occurrence of the disease. Addressing these factors is crucial for preventing and managing CPIV infections in susceptible animal populations.

Transmission

CPIV is highly transmissible when infected dogs cough, sneeze, or come into proximity with healthy dogs. In settings where dogs interact closely, such as dog parks, or other areas with a concentration of canines, the risk of transmission is heightened.

Risk Factors

Various factors can heighten the susceptibility to CPIV infection, including,

• Dogs kept in densely populated settings like kennels, shelters, or doggy daycares face an elevated risk of exposure.
• Furthermore, dogs with compromised immune systems, such as those grappling with other illnesses or recuperating from surgery, demonstrate increased vulnerability to the virus.

Signs and Symptoms

After CPIV invaded the body, the sick dog showed: intermittent cough, serous nasal fluid, normal appetite, and body temperature. If the external pathogenic factors cannot be eliminated, the cough intensifies, the body temperature rises, coughing is occasionally accompanied by vomiting, and the breath sounds become deep, rough, or rales on auscultation. If there is a secondary infection accompanied by other bacteria, gastrointestinal symptoms will also appear.

Diagnosis

In addition to pathogen isolation, we often develop detection methods and tools based on molecular diagnosis and immunodiagnosis for customers, mainly as follows:

• Molecular Diagnostics
  
  • RT-PCR: Single or multiplex RT-PCR can be developed for rapid detection of CPIV nucleic acids.
  • RT-LAMP: Design primers based on the conserved segment of the NP gene to establish a LAMP method.
  • Real-time Fluorescent Recombinase Polymerase Amplification (q-RPA): Design fluorescent probes and primers based on the conserved region of the CPIV-N gene to detect CPIV.
• Immunodiagnostics
  
  • Hemagglutination and Hemagglutination Inhibition Test: Collect fresh blood, use hemagglutination test to detect CPIV antigen and antigen hemagglutination value, and hemagglutination inhibition test to detect CPIV antibody.
  • ELISA: Detection of CPIV antibodies in serum by competition ELISA.
  • Lateral Flow Assay: A point-of-care assay for CPIV.
  • Colloidal Particle-based Immunoassay (CPIA): As far as the veterinary field is concerned, colloidal gold test strips are convenient, fast, and cheap.
  • Immunohistochemistry (IHC) Assay: IHC is an effective histopathological examination tool for detecting CPIV.

Treatment

At present, there exists no targeted antiviral remedy for CPIV infection. The recommended approach involves providing supportive care to alleviate symptoms and facilitate recovery. If a secondary bacterial infection is found, antibiotic treatment will be needed. The majority of dogs with CPIV exhibit recovery with appropriate care. However, severe cases may necessitate hospitalization and intensive medical intervention.

Prevention and Control

At present, the prevention of CPIV infection mainly relies on inoculation of inactivated vaccines or attenuated vaccines (vaccines containing CPIV antigens (usually as a combined vaccine)), which can produce neutralizing antibodies after some time through intramuscular or subcutaneous injections.

To fully prevent CPIV infection, the following measures need to be taken,

• For sick dogs, strict isolation measures should be taken immediately to prevent virus particles from being transmitted to healthy dogs through the air.
• Ensure a comfortable ambient temperature during dog breeding and reduce the adverse stimulation of cold air.
• The density and the dog population on the farm should be moderate, and the environmental hygiene should be maintained in good condition.

BioVenic is dedicated to combating CPIV infection through innovative solutions. Our efforts center around the development of advanced diagnostic products and methods, aiming to facilitate early detection of CPIV. Additionally, we are committed to the creation of more effective vaccines to prevent CPIV infection. If you are interested in collaboration or partnership, we encourage you to reach out to us.

Reference

1. Alayyoubi, Maher, et al. "Structure of the paramyxovirus parainfluenza virus 5 nucleoprotein–RNA complex." Proceedings of the National Academy of Sciences 112.14 (2015): E1792-E1799.