UPPER RESPIRATORY DISEASE

UPPER RESPIRATORY DISEASE

Fall and winter are prime seasons for upper respiratory infections in horses. 

Runny nose, cough, fever, listless, or depressed behavior…if your horse is showing these signs, there’s a good chance he has an upper respiratory infection. Fall, winter, and spring are prime time for diseases of the respiratory tract, and are often caused by one or more of four common pathogens.

An upper respiratory infection is caused by various bacteria, viruses, fungi and parasites. Various bacteria can infect the upper parts of the respiratory system and often cause pneumonia and weaken the immune system. One of the most common bacterial respiratory tract infections is known as strangles. Viruses such as the Equine influenza virus and the Equine Herpes virus (type 1 and 1V), which are similar to colds and flu in humans, are the primary cause of upper respiratory infections. Although fungal infections of the respiratory system are not as common as bacterial or viral, they may also develop. The lungs and guttural pouches are often more susceptible to fungal infections. When a parasitic infection invades the respiratory system, roundworms, threadworms or lungworms travel through the lungs and weaken the immune systems of young and aging horses.

Researchers have focused on four pathogens (disease-causing agents) that cause upper-respiratory infections in horses—Streptococcus equi subspecies equi, the bacteria that cause Strangles; Equine Influenza Virus (EIV); and Equine Herpesvirus types 1 and 4 (EHV-1 and EHV-4).

• Samples tested positive for one or more of the four pathogens in 201 cases, about 26 percent of the total. Fifteen of these horses were positive for two pathogens, and one had a triple infection.
• The highest detection rate was for EHV-4, which turned up in 82 cases. Infections with this virus (which can also cause pregnant mares to abort) were most common in fall and winter.
• Next most common was EIV, with 60 cases. It occurred mainly in winter and spring.
• S. equi, also most frequent in winter and spring, showed up in 49 cases. It was common in horses ages 6 to 10, while EHV-4 and EIV infections were more common in 1- to 5-year-olds.
• EHV-1, which can cause neurological disease as well as upper-respiratory infection and abortion, ranked last, with 23 cases. It was generally seen in older horses and, like the other infections, was less common in summer.

Save on Zylexis at Allivet.com

Zylexis is an inactivated (killed) Parapox Ovis Virus Immunomodulator. Aids in the reduction of upper respiratory disease associated with equine herpesvirus types 1 and 4. Demonstrated safety: none of the 333 Zylexis treated horses had visible or palpable reactions at the injection site or systemic reactions. Zylexis is indicated for use in healthy horses over 4 months of age. Treatment is recommended during disease episodes or prior to stress-inducing situations. Retreatment is recommended during subsequent disease episodes or prior to stress-inducing situations. EHV 1 and 4 infections can be easily triggered by common stressors to horses including trailering, competition, breeding and environmental changes.

Directions: Aseptically rehydrate the freeze-dried component with the sterile diluent provided, shake well and administer 2mL intramuscularly. Repeat the 2mL dose on days 2 and 9 following the initial dose.

Horses with respiratory illness should be examined by a veterinarian and should be kept away from healthy horses. To avoid exposing other horses to disease, owners should care for the sick horses after caring for healthy animals, and should not use the same buckets, tack, and grooming supplies for sick and well horses. Those coming in contact with a sick horse should wash their hands, and equipment should be disinfected before it is used on other horses.