The horse mumps is characterized by being a highly contagious process, not very deadly and of bacterial origin, unlike mumps in people, whose origin is viral. Horses with mumps are usually young foals that are dull, with a swelling under the jaw more or less evident depending on the severity of the disease; if this is aggressive, pus may be expelled through the skin to the outside. Keepers are usually quick to notice that something is wrong with their horse, and most of the time it has a good prognosis with proper treatment implanted by an equine veterinarian.
In this article on our site we will describe the types of mumps in horses, their symptoms, diagnosis and treatment.
What is equine mumps?
This is a highly contagious disease that affects equids all over the world and is characterized by respiratory disorders high with suppurative inflammation of nearby lymph nodes, frequently associated with pus abscesses. It is a disease with low mortality, not exceeding 2-3% of those infected and with an incubation period of up to eight days from the time the horse is infected until the clinical signs appear. Other names by which this disease is known are equine adenitis, equine distemper, strangles or gurma.
All equids can suffer from equine mumps, with horses being more susceptible than mules or donkeys, and appearing more frequently in horses between 4 months and 2 years of age. Children under 4 months due to immunity from colostrum and from 4 months to 2 years because they still do not have immunity or vaccine antibodies.
Causes of mumps in horses
Equine mumps is caused by a bacterium of the genus Streptococcus, specifically Streptococcus equi, subspecies Equi. Occasionally, this bacterium may be associated with S. Equi, subspecies Zooepidermicus, causing secondary complications.
After developing the disease, 75% of horses develop lasting immunity However, animals affected by this pathology can remain permanently infected within the guttural bags (diverticula of the Eustachian tubes that connect the inner ear with the larynx) and can secrete the bacteria with nasal exudate or saliva even for months or years, all without showing symptoms and being a source of infection for other horses.
How is mumps spread in horses?
Equine mumps can be spread directly or indirectly. The direct contagion occurs through contact with a sick animal or an asymptomatic carrier. The indirect contagion is produced by:
- Water (the bacteria can resist from 4 to 8 weeks in it).
- Feeders and drinkers contaminated by bacteria.
- Respiratory aerosols.
- Hands of caregivers or veterinarians.
There are certain conditions that promote the spread of mumps, distemper or equine adenitis, such as groups of animals of various origins, overcrowding, cold winter temperatures, poor ventilation, little physical activity of the horse and vitamin deficiencies.
Symptoms of mumps in horses
The symptoms of equine mumps will depend on the type of mumps. Thus, there are two types of mumps in horses:
- Classic Horse Mumps
- Bastard horse mumps
Classic Horse Mumps
In 80% of cases, the disease follows the classic course where the bacteria enter through the nostrils and reach the tonsils to cause inflammation. Later, it passes to the regional lymph nodes (submandibular and retropharyngeal) and after a few days pus forms in them, which will be encapsulated creating abscesses that in the last phase of the process soften until they finally drain, fistulating to the outside through the submandibular area. In other cases, chondroids (pus of a solid consistency) form in the guttural bags and become chronic forming an empyema (accumulation of pus).
To better understand this whole process, the clinical signs that horses present with this form of mumps are the following:
- First phase: fever (39.5-41ºC), anorexia, apathy, depression, inflammation of the nasal and oral mucosa.
- Second phase: decrease in fever, cough, runny nose, enlarged lymph nodes becoming hot, hard and painful, pharyngitis which leads to a loss of appetite due to the pain it causes.
- Third phase: fever returns, discharge of pus from nose and mouth, lymph nodes become soft, diffuse and painless, chondroids and empyema of the guttural bags.
It is normal for horses to recover after this process, but sometimes, there are complications such as:
- Sinusitis due to bacterial colonization of the paranasal sinuses.
- Pneumonia due to aspiration of pus when swallowing.
- Asphyxia due to compression of the larynx and pharynx if the inflammation is severe.
- Laryngeal hemiplegia due to compression of the recurrent laryngeal nerve by the inflammatory process.
- Infection of other lymph nodes such as those of the intestine (mesenteric), chest (mediastinal), prescapular and cervical.
Bastard horse mumps
However, in the remaining 20%, the process is not limited to the area we have discussed, but can pass via blood or lymph to other lymph nodes and organs (lung, liver, kidney, spleen, mesentery, brain), where it will form abscesses. It can also target muscle, skin, reproductive tract or produce reactions mediated by the horse's immune system. This form is known as bastard equine mumps, where our horse can manifest
- Abscesses in various organs: lung, liver, intestine, spleen, kidney, brain.
- Mastitis or inflammation of the mammary gland caused by contagion from the foal to the mother during lactation.
- Skin blemishes due to accumulation of fluid on the head, giving them a "hippopotamus head" appearance.
- Reproductive disorders.
- Skin changes.
- Immune-mediated reactions: pHemorrhagic purpura (inflammation of the capillaries and mucosal hemorrhages), myositis (muscle infarction and progressive atrophy) and/or glomerulonephritis (inflammation of the renal glomerulus, which is where urine is filtered).
Equine Mumps Diagnosis
Mumps in horses can be diagnosed through different tests or examinations, as we will see below:
Differential Diagnosis
Equine mumps, due to its respiratory symptoms, can be confused with the following conditions in horses:
- Rhodococcus equi: which affects young animals from 1 to 6 months of age, producing, among other things, suppurative pneumonia.
- Influenza or horse flu.
- Equine herpesvirus (type 1 and 4) because they produce respiratory forms.
- Secondary infections by E. equi zooepidermicus, which causes respiratory processes and inflammation of the uterine endometrium.
Clinical Diagnosis
Mumps in the horse should be suspected if a horse, especially under two years of age, exhibits respiratory symptoms with clear swelling of the submandibular region, especially especially if he has had close contact with other horses.
DiagnosticLab
A diagnosis of horse mumps is confirmed by taking samples and sending them to the laboratory where they will test for the bacteria. It must be taken into account that Streptococcus equi does not persist well in the medium, so to avoid losing viability, refrigerated samples should be sent as soon as possible. These samples can be:
- Pus from the abscesses.
- Nasal swabs.
- Nasal, tracheobronchial or guttural pouch washes.
The laboratory tests that can diagnose the disease are:
- Plain in blood or Columbia agar medium.
- PCR.
- ELISA (does not differentiate vaccinated from infected and young people can test positive for maternal immunity).
How to cure mumps in horses? - Treatment
Treatment of equine mumps will depend on several factors, such as the type of mumps. Likewise, other measures will be taken into account to help the animal overcome the disease.
Specific treatment
The specific or etiological treatment aims to kill the bacteria that cause the disease. In this way, depending on the type of mumps it causes, the treatment will be as follows:
- Treatment of classical horse mumps: mainly beta-lactam antibiotics such as penicillin are used, being effective in the acute phase when abscesses have not appeared. When these have already appeared, it is advisable to use heat and drain them and only use antibiotics in severe cases.
- Treatment of equine bastard mumps: abscesses should be drained and prolonged intravenous antibiotics given.
Symptomatic treatment
To treat the symptoms that horse mumps can cause, the following will be used:
- Anti-inflammatories such as flunixin meglubine, phenylbutazone or meloxicam.
- Antipyretics to reduce fever such as metinazole
- Corticosteroids or anti-endotoxics such as dexamethasone or pentoxillin for hemorrhagic purpura.
- Fluidotherapy.
Hygienic-sanitary treatment
Consists of applying a series of measures to reduce the concentration of bacteria in the environment, as well as maintain a suitable environment in the area where the animal is to help it overcome the infection. Thus, the measures to be taken are:
- Isolation of the animal.
- Keep area clean.
- Temperature control.
- Rest of the horse.
- Moist and soft feeding at a good height so they don't have to strain their necks. Discover the Keys for the correct feeding of horses.
- Give vitamins or a supplement to strengthen their immunity.
Surgical treatment
Sometimes it is necessary to remove abscesses as follows:
- Use hot cloths to soften it.
- Shave the area.
- Cleaning and disinfection.
- Incision in the lower area of the abscess.
- Drain and flush.
- Disinfection with chlorhexidine or povidone-iodine.
- Disinfection with antibiotics and give anti-inflammatory for 10 days.
In cases of suffocation or severe difficulty breathing, an emergency tracheotomy (incision in the trachea) should be performed.
These processes can only be carried out by a veterinarian in his clinic, you should never try to drain an abscess or perform a tracheotomy on your own because you could worsen the clinical picture. Therefore, if you observe any of the symptoms mentioned and suspect that your horse may have mumps, do not hesitate to call a professional.
