By Dr. Pawan Kumar                                                                                                        


There are several infectious diseases that can affect your pet and can be protected against by vaccination. While most of these diseases are kept in check due to the high rate of vaccination, others are still regularly encountered. 


Infectious diseases are caused by organisms such as bacteria, viruses, fungi, or parasites. There are a few diseases occurring in animals that can be transferred to humans as well. Infectious diseases that are transmitted between species from animals to humans or humans to animals are called zoonotic diseases — leptospirosis, rabies, and brucellosis, for example. A zoonotic disease can emerge as the result of increased human contact with the animal host(s), animal tissues, vectors, or environmental sources of the pathogens. 


Some of the most common infections that tend to occur in dogs and cats are as follows:


Infectious diseases in dogs



  • Canine Parvoviral Infection: Parvo virus is very contagious and attacks the gastrointestinal system, causing fever, vomiting and severe diarrhea. It is spread by direct contact between dogs as well as through contaminated stool, surfaces, bowls, collars, leashes, equipment and the hands and clothing of people. It can also survive in the soil for years, making the virus hard to kill. Fortunately, there is a vaccine against parvo. It is considered a "core" vaccine and is recommended for all dogs. Along with vaccination, correct electrolyte balance in the pet should be maintained.

  • Canine Distemper: Canine distemper is a highly contagious, whole body, viral disease in dogs and cats. It is a fatal, multisystemic disease that affects the respiratory, gastrointestinal and central nervous system of the animal. Distemper is caused by the canine distemper virus (CDV). The treatment typically consists of supportive care and attempts to prevent secondary infections; control vomiting, diarrhoea and combat dehydration through the administration of fluids. Pets infected with canine distemper must be separated from other dogs to minimise the risk of further infection.

  • Canine Leptospirosis: Leptospirosis is a bacterial disease that primarily affects the liver or kidneys. High fever, yellowish skin, lethargy, vomiting, polyuria, and polydipsia are common signs of canine leptospirosis. It can be transmitted by ingesting infected urine or contaminated rodents.

  • Kennel Cough: It refers to any infectious disease which is associated with coughing. Several viruses and bacteria can cause kennel cough including adenovirus type 2 parainfluenza virus, canine coronavirus and the bacterium Bordetella bronchiseptica. Veterinarians recommended vaccination programs which include adenovirus and parainfluenza.

  • Infectious Canine Hepatitis: It is a contagious disease among dogs with signs varying from a slight fever and congestion of the mucous membranes to severe depression, marked leukopenia, and coagulation disorders. It is spread through direct contact or oral route. The treatment includes intensive care with hospitalisation.

  • Tick-Borne Disease: Ticks are parasites that attach to animals, feed on blood and transmit the disease directly to the host’s system. The most common tick-borne disease in dogs includes Babesiosis, Ehrlichiosis, and Anaplasmosis. The most effective thing will be a regular tick and flea control programme that can help in preventing tick-borne diseases.


Infectious diseases in cats



  • Feline Panleukopenia/ Distemper: Feline Panleukopenia/Distemper is a highly contagious fatal disease affecting kittens with signs like lethargy, lack of appetite, weight loss, and fluctuating fever. The feline Distemper infects and kills cells that are rapidly growing and dividing, such as those in the bone marrow, intestines and the developing foetus of the cat.

  • Feline Infectious Peritonitis: Feline infectious peritonitis (FIP) is a viral disease of cats caused by certain strains of a virus called the feline coronavirus. Cats infected with FeCV usually do not show any symptoms during the initial viral infection but may occasionally experience brief bouts of diarrhea and/or mild upper respiratory signs from which they recover naturally.

  • Feline Calicivirus: It is the virus responsible for upper respiratory infections and oral diseases with the most common signs including sneezing and ulcers in the mouth.

  • Feline Viral Rhinotracheitis / Herpesvirus (FVR): FVR is a major cause of upper respiratory disease in cats and is the most common cause of conjunctivitis. It spreads through direct contact, saliva and fomites.

  • Feline Mycoplasmosis: Feline Mycoplasmosis is caused by Mycoplasma Haemofelis and affects the red blood cells in cats by a microscopic blood bacterial parasite that destroys red blood cells leading to anemia

  • Parasitic and Fungal Infections: Fungal infections like Dermatophytes and Fungal Dermatitis are common infections in cats. Parasites including ticks and fleas, mites, roundworms, hookworms, and tapeworms will cause infections in cats. 


Prevention Measures


Some precautions can be considered to prevent infectious diseases in your pet such as-



  • Keep your pet’s immunisations up to date. Vaccination protects a variety of infectious diseases that can affect your pet. A number of these diseases depend on high rates of vaccination in the pet population to keep them healthy

  • Take your pet to a veterinarian regularly for a health checkup

  • Ensure your pet’s bedding and living area are kept clean

  • Provide a balanced diet to your pets, keep clean and fresh water available 

  • Litter boxes for cats should be cleaned every day


The author is the Chief Medical Officer at Cessna Lifeline Hospitals