Infectious diseases – viruses, bacteria and co.
When yellow mucus drips from the nose and the thermometer reads fever, the reaction is often split – part alarmism, part ignorance. If the horse's illness is contagious, clear rules are needed within the stable community. But how often do corona, herpes and other viruses occur?. before? And what protection is safe?
With increasing globalization and travel, infectious diseases are playing an increasingly important role in the lives of people and horses as triggers of dangerous epidemics. A current example is probably the Corona virus, which is currently rampant worldwide. In addition, stall or group housing in cramped stalls and large herds, little exercise and fresh air, tournaments, marketing and stress greatly favor the spread of pathogens in horses. For this reason, it has recently become increasingly important for people and animals to take appropriate measures to protect themselves and others.
After the outbreak of an infection, a doctor can usually only initiate symptomatic treatment of the affected animal, although the outcome of such therapy is not always predictable. In addition, the affected horse can infect other animals in the herd and is therefore a potential danger.
What infections are there? How do the diseases progress? What can be done about it?
Many questions – hopefully some answers!
Here comes our small lexicon of the most common horse infections and what you can do against it.
Equine Corona Virus (ECoV) – not only in humans
As with dogs, cats, cattle and pigs, the Corona virus has been known in horses for over 20 years. However, connections with the virus, which is dangerous for humans, have hardly been researched at the moment. Only recent studies and a recent case in Arizona point to a disease of the gastrointestinal tract with fever, colic and diarrhea in horses without respiratory involvement. Diseases with the Equine Corona Virus have so far mainly occurred in the cold season from November to May. According to current reports from the Equine Disease Communication Center, they are not contagious to humans! A vaccine against ECoV is currently being worked on. An antidote for cows is currently being tested in Japan and parallel research is being carried out to determine whether it may also be able to help horses. It remains to be seen whether the newly discovered human corona virus can infect other species.
The clinical symptoms of the disease include loss of appetite, lethargy and fever. Partly diarrhea occurs. Mild colic symptoms on. Neurological abnormalities such as muscle twitching, depression or recumbency are less common. Transmission occurs primarily via the fecal-oral route.
Currently there is no real therapy for Equine Corona Virus infections.
Treatment is purely symptomatic and usually consists of increased fluid intake and avoidance of further infections. Suspicious horses have to be quarantined immediately. Due to the massive excretion of pathogens with the feces, strict hygiene measures are to be observed. Diseased animals must be isolated until viruses can no longer be detected in the feces. Pathogen excretion usually varies between 5 and 21 days after infection.
INFLUENZA (equine influenza)
Equine influenza (horse flu) is an extremely contagious viral infection localized in the respiratory organs. It is usually transmitted by droplet infection or direct animal-to-animal contact, but can also be spread indirectly through contaminated water, feed or equipment. All objects shared by several horses can be carriers. These include z.B. also drinkers, hayracks, feed bowls, pitchforks, brooms, shovels, rakes, toys, halters, clothing, helmets, ropes, blankets, grooming equipment,……………… The major problem of equine influenza is its rapid spread throughout the entire horse population, whereby all animals in a stable can become ill in a short time.
Typical signs, such as high fever, nasal and eye discharge, dry cough, shortness of breath, weakness and loss of appetite, develop after a short incubation period of only one to two days. Immediate quarantine and immobilization of the horse are the countermeasures to be taken first. In addition, appropriate veterinary treatment (usually with antipyretics and antibiotics) must be initiated to counteract chronic damage such as pneumonia or myocarditis.
Preventive and safe protection of your horse can only be achieved by an annual vaccination!
Although influenza protection lasts for more than a year, the FN even prescribes a six-monthly vaccination interval at events.
Tetanus (lockjaw) – wound infection with fatal consequences
The tetanus disease is caused by a spore-forming bacterium. The bacteria settle in the intestine. Are excreted with the feces. In the soil they are present as spores. Can persist there for years. The pathogens enter the body through external, often inconspicuous injuries, where they transform into active, motile and multiplying bacteria and form a highly concentrated neurotoxin. This floods the body through the blood and lymph channels, sticks to the nerve cells and leads to muscle spasms, colicky symptoms, stiffness or paralysis. In the worst case, the horse dies after paralysis of the swallowing and breathing muscles.
Although there is an antidote and medication for muscle relaxation to ease the course of the disease, the more nerve toxin that settles in the nerve tie, the lower the chances of recovery. Since horses are very susceptible to tetanus and its course is usually fatal, ALL horses should be vaccinated against tetanus. After basic immunization there is a two-year protection.
Equine herpes (EHV) – almost all horses carry the virus
Equine herpes viruses, together with the influenza viruses, are among the most frequently occurring pathogens. They cause respiratory diseases, central nervous disorders (paralysis, recumbency, death) or viral abortions and are not transmissible to humans or dogs. The most important representatives of these malignant pathogens are Equine Herpesviruses 1 and 4 of a total of 5 types. These two types affect the respiratory system as well as the reproductive system and the central nervous system. All types cause different manifestations.
The herpes virus type 1 can cause the following symptoms in horses: – Abortions (miscarriage) – Respiratory problems – High fever – Watery nasal and eye discharge – Swollen lymph nodes – Inability to feed Lethargy – Nervous system disease, damage to the spinal cord – Movement and/or coordination problems, paralysis, recumbency, problems defecating and urinating
Herpes virus type 2 is mainly involved in eye infections.
Herpes virus type 3 causes itchy vesicular rash on genitals.
Herpes virus type 4 can also cause respiratory problems, but the course is usually milder than with type 1. The herpes virus type 5, which has probably been underestimated until now, was for many years only-. conjunctivitis associated with. Recent studies show that there is an overgrowth of connective tie in the lungs. This causes respiratory problems, coughing and fevers in the horse.
Any horse is at risk because transmission of the highly contagious herpes viruses occurs through direct contact and droplet infection, but also indirectly through objects such as hands, clothing, or grooming equipment! Anything shared can be infectious . Stable hygiene is also a top priority in the case of herpes! Most horses that carry the herpes virus show no signs of disease, but excrete the virus for life and thus infect other horses unnoticed. Similar to humans, once infected, a horse remains a virus carrier throughout its life. After an initial infection, there is usually an unstable balance between the virus and the immune defense of the infected horse. Through stress or weakening of the immune system, this balance is disturbed, the herpes viruses are activated. These can now multiply en masse, the horse becomes ill and again excretes viruses with all the secretions of the respiratory tract. This is how the herpes virus spreads quickly throughout the horse population.
If an outbreak of herpes occurs, only symptomatic treatment is possible. There is no remedy against the virus itself!
The most important measure against the spread of the virus is vaccination, always at 6-month intervals.
Vaccination unfortunately does not provide complete protection, but the excretion of the pathogens is significantly reduced. For this reason, experts recommend always vaccinating the entire stock of a stable, as otherwise individual horses can continue to be carriers and excretors of the virus.
It is also important to keep horses in optimal health to avoid giving the herpes virus a chance to break out. This includes ensuring that horses are dewormed regularly and receive appropriate, balanced feeding and care!
Rabies – Agonizing death after 4 to 5 days Notifiable
With the exception of a few isolated areas such as Great Britain, Australia, Sweden and Norway, rabies can be found almost everywhere in the world. Vaccination campaigns have largely reduced the incidence of the disease, but it still recurs and is far from being eradicated. The pathogens are usually transmitted through saliva after a bite from infected animals. Reproduce rapidly throughout the body via the central nervous system.
Symptoms in horses are manifested mainly by nerve failures. Sick animals gradually lose control of their muscles, staggering or swaying. Many are irritable or even aggressive, nibbling on wood or hitting walls and doors in a furious rage. There is also a silent form of rabies. Here the animals become shy and apathetic, injure themselves, lame and no longer drink. Finally, horses with rabies usually lay down, fall into a coma and usually die in agony after 4-5 days, unless the veterinary office has already ordered the immediate killing.
Rabies is also a life-threatening disease for humans, because it almost always takes a fatal course.
Due to the high risk of infection, therapy in animals is prohibited!
However, vaccination is a preventive measure.
Druse – Anything but "just" a cough
Druse is an acute, febrile infectious disease. Bacteria cause purulent inflammation of the upper airways, swelling of the lymph nodes and even abscess formation. Mattness, fever, cough, loss of appetite and initially watery, then purulent nasal discharge occur. Horses are in pain, breathing is restricted, respiratory distress is imminent. Young horses or seniors are at risk, their immune system is often impaired. The pathogen is transmitted by insects, shared feeding and drinking utensils as well as by droplet infection and direct contact. The bacteria are weather-resistant. Even on hard surfaces extremely long-lasting.
Since the pathogens that cause druse change rapidly and constantly, similar to the influenza virus, there is a vaccine available, but it is not 100% effective and only serves as an emergency measure for horses at risk of infection. Prophylactic measures: Preventing the introduction of bacteria into the horse population, meticulous pasture and stable hygiene, strengthening the horses' immune system.
A healthy and clean stable reduces the risk of infection!
WEST NIL VIRUS DISEASE Notifiable
West Nile virus (WNV), which originates in Africa, is transmitted to our native mammals through the bite of the Culex mosquito. Horses and humans are particularly affected, but the virus is not further transmitted. The virus enters the brain and spinal cord through the bloodstream, causing inflammation that can lead to severe and potentially fatal neurological symptoms. Many horses die from the virus and even after recovery, there may be phases of failure that cannot be cured.
These symptoms may appear within 3-15 days of infection: – Fever and flu-like symptoms – Loss of appetite – Depression or lethargy – Inability to swallow – Visual disturbances – Head pressing or tilting – Stumbling or tripping – Muscle weakness or twitching – Wandering aimlessly – Partial paralysis – Difficulty standing up, lying down – Convulsions – Coma
There is no treatment for West Nile fever. Vaccination and effective control of mosquitoes using insecticides, fly blankets, fly caps, etc., Are the best ways to effectively protect our horses.
EQUINE VIRUS ARTERITIS (EAV) EQUINE INFECTIOUS ARTERITIS, HORSE DISEASE, RED RUNNING DISEASE, PINK EYE Reportable
The pathogen of equine viral arteritis (EVA), known by many names, is a highly aggressive virus that is transmitted by direct contact through the air or respiratory secretions. Spread via tear fluid, blood, urine, semen and feces is also possible. The disease caused by the virus shows itself with flu-like symptoms, but also leads to abortions or to the birth of weak foals.
The following symptoms may occur: – Fever – Loss of appetite – Depression or lethargy – Flu-like symptoms – Conjunctivitis with eye discharge – Swelling of limbs, scrotum or mammary – Redness of skin, rash, edema – Pregnant mares: Abortions – Foals up to three months of age: Respiratory problems (pneumonia) and/or digestive problems – Stallions: temporary subfertility
Equine arteritis is often mild or asymptomatic. However, protection by vaccination is possible.
Equine Infectious Anemia (EIA), contagious anemia of equines Notifiable
The virus of EIA occurs worldwide, but especially in Asia, South America and Eastern Europe (Romania). It affects equines (horses, ponies, donkeys) but is not infectious to other species or humans. After infection, the EIA viruses multiply rapidly, the body's defense system reacts, tries to eradicate the viruses, but also dissolves its own blood cells in the process. For the transmission is v. a. Blood decisive. The infection is mainly transmitted over short distances by blood-sucking insects such as horseflies. Infected equidae can pass on the virus via body secretions such as saliva, milk and semen (indirectly also via grooming utensils, bowls, watering troughs,…).
Symptoms: – High fever – Apathy, weakness, ataxia – Pale or yellow mucous membranes – Pinpoint hemorrhages on mucous membranes, eyelid conjunctiva and underside of tongue – Heart palpitations and arrhythmia – Decline in performance – Anemia – Edema formation on lower abdomen / extremities
Once infected with the EIA virus, animals remain virus carriers for the rest of their lives and pose a constant risk of infection to other equids, which is why animals that test positive must be euthanized immediately in Germany!
The EIA is not curable, a vaccination does not exist!
Every horse owner should try to minimize the risk: – One hoofed horse before purchase resp. have the stables checked for EIA before changing stables – keep stables clean if necessary. Avoid common use of equipment such as saddlery, bridles and grooming equipment or clean and disinfect equipment after use – Move pastures to times when there is less fly activity of transmitting insects – Keep pastures and paddocks as dry as possible – Treat animals with repellents and protect them with fly blankets
Borna disease (BORNA) Notifiable since March 2020
Borna disease, which is often fatal, is a contagious inflammation of the brain and spinal cord that mainly affects horses and sheep and is caused by the Borna disease virus (BoDV). The virus is also transmissible to humans. Reproduces mainly in shrews. In Germany, Bornasche disease in horses is more common in Saxony, Saxony-Anhalt, Thuringia, Hesse, Baden-Wurttemberg and Bavaria. There are many horses that have had contact with Borna disease virus, have developed antibodies and are healthy. The virus is transmitted through the air or direct contact, the animals have the virus in their saliva, nasal and eye secretions, but also in excretions such as urine or sweat. Horses become infected through direct contact with diseased animals or they inhale the virus. It is noticeable that a particularly large number of animals become infected with Borna's disease in the months from April to June. After horses become infected, some time may pass before the disease breaks out (incubation period). In most cases, the pathogen lies dormant in the brain for life. Triggers little or no symptoms. But even these horses can one day get a bout of infection and then pass on the virus.
Symptoms of Borna's disease: – Apathy, unusual behavior of the horse – Temperature increase – Chewing difficulties and refusal to eat ("empty chewing") – Slight diarrhea – Drowsiness: the horse no longer responds to address – The horses are very jumpy, suddenly become agitated – Certain areas of the horse's skin are hypersensitive – Neurological disorders: Coordination and orientation problems (legs collapse, stiff gait, head crooked or low, maneuvering and circling). – The horse's tongue and ocular nerves may be paralyzed – The horses react very strongly to environmental stimuli such as light and noise – Colic symptoms: constipation, diarrhea, foul-smelling feces, frequent colic, difficult to treat – Gait impurities – Chronic lameness – Head shaking ("headshaking") – Swallowing difficulties
Borna virus is detected by antibody detection. Unfortunately, a therapy of Borna's disease is only possible to a limited extent, affected animals usually have to be killed due to the high risk of infection. The last approved vaccine against Borna virus was banned, so neither prophylaxis nor prevention is possible today.