Scrapie is a transmissible brain disease in sheep and goats that has been known for over two hundred years. Scrapie is also potentially dangerous for humans, even if the disease-causing effect is significantly lower than in sheep.
What is scrapie?
Scrapie is one of the so-called prion diseases, which also includes Creutzfeldt-Jakob disease in humans, BSE in cattle, CWD in deer, TME in mink and FSE in cats.
Prions are malformed proteins (proteins) that cause brain damage. With scrapie, starch-like substances are deposited in the brain, which lead to its regression. The brain progressively develops a spongiform structure with holes. See beautyphoon for What is Jaw Cyst.
Meal from scrapie-infected sheep fed to cattle transmitted the pathogen and caused BSE. The English term scrapie is due to the fact that sick sheep often scour their wool because of severe itching. The German name traber disorder refers to abnormalities in gait. If the animal disease scrapie occurs, there is an obligation to report in Germany. In 2011, 19 cases of illness were known.
Causes
Prions are proteins that are also found in healthy animal bodies. It is only through incorrect binding of these proteins that they acquire their disease-causing significance and lead to scrapie.
The malformed prions are similar to viruses in their effect as organic toxins. But unlike bacteria and viruses, the prions are resistant to heat and cannot be combated by disinfection measures.
According to the current state of knowledge, scrapie is a transmissible disease, for the outbreak of which a corresponding genetic disposition is of great importance. However, the details of the transmission route have not yet been researched.
In the case of scrapie, there can be a few years between infection and the onset of the symptoms of the disease, during which the animals still appear healthy. At the time of disease, the average age of scrapie animals is 3.5 years.
Symptoms, Ailments & Signs
Scrapery primarily leads to behavioral problems in animals. Sick animals are nervous or frightened and also tremble. The movement sequences are also impaired, so that the animals often stagger, trot or hop. As the disease progresses, there is weight loss and persistent itching, through which the wool or fur of the animals is rubbed off.
The other symptoms vary greatly from animal to animal, whereby scrapie always ends fatally. The disease can also be fatal in humans. Before that, comparable symptoms appear: tremors, inner restlessness and an unusually severe itching. The first signs of the disease usually appear a few hours to days after infection.
The disease then rapidly increases in intensity and eventually leads to organ disorders, cardiovascular problems and inflammation throughout the body. In the final stage, the patient falls into a coma. Additional skin changes also occur. At this stage, scrapie can be recognized by the noticeable discoloration of the eyes. Some patients also lose their hair or their skin turns gray. Patients eventually die of heart failure or sepsis.
Diagnosis & History
A symptom of scrapie disease is a change in behavior in the animals, which appear skittish and nervous. The movements of the tumbling, hopping, trotting or often trembling animals are disturbed. Itching makes them scour their wool. Furthermore, the weight of the diseased animals decreases. However, each animal develops individual symptoms, especially in the early stages of the disease with scrapie.
A reliable diagnosis of scrapie can currently only be made after the death of the animal by examining a tissue sample from the brain. Although attempts are being made to diagnose the disease by examining samples of lymphoid tissue in living animals, the results of this method have not yet been scientifically accepted. Once scrapie has broken out, the disease is fatal in all cases within a few weeks or months.
Complications
In the worst case, this disease can lead to the death of the affected person. However, this case only occurs very rarely and can usually be avoided relatively easily. Those affected primarily suffer from a strong inner restlessness and a frightfulness. These complaints have a very negative effect on the quality of life of the patient and thus also on the everyday life of the person concerned.
It causes severe shaking and anxiety. Gait disorders and coordination disorders can also occur as a result of scrapie and make everyday life difficult for the patient. Most sufferers lose weight over the course of the disease and continue to suffer from itchy skin. The symptoms often lead to depression or other psychological problems.
A direct and causal treatment of this disease is usually not possible. Those affected can only limit the complaints and symptoms, but cannot completely combat the disease. This may also result in a reduced life expectancy for the patient. A therapy may be developed in the next few years. However, there are no particular complications in the treatment of the symptoms.
When should you go to the doctor?
In humans, scrapie should always be treated by a doctor. Only early and correct treatment can prevent further compilations and, in the worst case, death. Self-healing cannot occur with scrapie, so that the affected person is dependent on medical treatment. A doctor should be consulted if the affected person suffers from severe itching and tremors due to scrapie. The tremor occurs all over the body and can significantly reduce the quality of life of the person concerned.
There is also a very strong inner restlessness and a coma if the scrapie is not treated. If these symptoms occur, a doctor should be consulted immediately. The heart is also damaged by scrapie, so sudden heart problems can also indicate the disease. In the case of scrapie, a hospital should be visited immediately. If the disease is recognized and treated early, there are usually no special complications. Only if scrapie is not treated does the life expectancy of the affected person decrease drastically.
Treatment & Therapy
As with all other prion diseases, there are currently no therapeutic options for treating animals suffering from scrapie. However, attempts are being made to prevent the spread of scrapie (traber disease) by isolating the animals prophylactically. However, since there can be periods of time between the infection and the appearance of the first symptoms of scrapie, the affected animals are only isolated at a relatively late point in time and their effectiveness is therefore limited.
After emergency slaughter of the animals suffering from scrapie, the carcasses are burned to eliminate sources of infection. Researchers at the Universities of Bonn and Munich developed the first therapeutic approaches, using a new treatment method to extend the lifespan of similarly infected mice. The researchers used special RNA molecules (relatives to DNA) that attach themselves to the genes in brain cells that are responsible for making the faulty prions.
With this method, the production of pathological (disease-causing) proteins could be reduced by 97%. However, the RNA-treated animals only increased their lifespan by a third if they managed to protect the majority of their brain cells. However, the researchers doubt whether it will be possible to develop a therapy that can reach all brain cells using this so-called RNA interference method. Research into an effective therapy for scrapie will take several more years.
Prevention
A prophylactic measure consists in the selection and emergency slaughter of animals suffering from scrapie. Because of the long incubation period, however, isolation of the animals is only effective to a limited extent. A long-term way to combat scrapie is to develop breeding programs that use genetic testing to pre-determine the disease susceptibility of animals intended for breeding. In addition, veterinary monitoring is carried out, with which herds of goats and sheep are examined for scrapie by means of area-wide spot checks.
Aftercare
According to the current state of science, there is no treatment option for scrapie. After an animal becomes ill with scrapies, death occurs between two weeks and six months after the onset of the first symptoms. For this reason, follow-up care is not required.
However, after the onset of the disease, the measures are aimed at combating a possible epidemic. According to EU law, cases of scrapies must be reported to the competent authorities. The subsequent measures differ in detail from country to country. As a rule, diseased animals such as sheep or goats are killed.
The carcasses must then be disposed of safely so that they no longer pose a risk of infection. In addition, extensive quarantine measures are usually ordered in connection with the long incubation period of scrapie. They are intended to ensure that healthy animals do not become infected.
Diseases that have not yet been recognized should also be recognized in apparently healthy animals. In addition, the official veterinarian can order that animals belonging to a high-risk group be killed within a herd. In addition, measures following a scrapies disease are also aimed at breeding resistant breeds and thus preventing future outbreaks.
You can do that yourself
Some diseases can be cured with self-medication. Tried and tested recipes promise at least a relief of the symptoms. This makes going to the doctor unnecessary. These self-help measures are not possible if scrapie is suspected. Because there is no effective way. Neither a doctor nor a keeper can heal a goat or a sheep.
Only isolation is suitable to prevent contamination of other animals. The animal is then slaughtered. The carcass is cremated to avoid any transmission.
The diagnosis of scrapie presents difficulties. So far, it can only be clearly identified in dead animals. Pet owners are initially only left with indications of the disease. However, the typical behavioral changes and signs have only limited significance. As a result, everyday life harbors a high degree of uncertainty.
Another problem is that it takes two to five years for scrapie to break out. An infectious animal can therefore infect the entire herd unnoticed. In practice, it is recommended that sheep and goat farmers keep at least an overview of the herd population.