Cat Scratch Disease: Causes, Symptoms & Treatment

In cat scratch disease, which is caused by bacteria, the pathogen enters the human organism mainly through scratch injuries of the cats. The cats themselves either do not become ill at all or only mildly.

What is cat scratch disease?

Cat scratch disease is a common infectious disease in which the local lymph nodes are inflamed. Fever, limb pain and headache may also be present. Cat scratch disease, which is transmitted from infected cats to humans through scratch or bite wounds, is usually harmless. The pathogens include the bacteria Bartonella henselae and Bartonella clarridgeiae. It is suspected that the cat can also become infected through flea infestation, although the assumption is not proven. According to studies, about every tenth cat carries the bacteria. The disease is not transmitted from person to person, but only from cat to person. Especially people with a weakened immune system are more affected by cat scratch disease and more often.

Causes

In principle, cat scratch disease can affect anyone, but cat owners are particularly at risk because of the route of transmission. Because young animals in particular are contagious, cat scratch disease is more common in households where there are very young cats, but the disease can also be transmitted by older animals. Most people affected by cat scratch disease are up to 21 years old or still in childhood. The reason for this is that children often have intimate contact with the pet and on the other hand do not yet have a fully developed immune system. However, adults with a weakened immune system are also more likely to contract cat scratch disease. In addition, they often show a more severe course. The pathogen reaches the claws of a cat via various routes: When the animal licks its paws, the bacteria, which are contained in the saliva and blood, reach the claws. Another possibility is when fleas settle and suck the cat’s blood. With the feces of the fleas are excreted and are in the fur. Since the puncture site is itchy, the cat scratches and the fleas‘ feces get under the claws. If the cat licks a human skin site that has been previously scratched or is pre-damaged, the pathogen can be transmitted. In addition, since the flea also bites humans, direct transmission is possible, although this is much less common.

Symptoms, complaints and signs

The initial symptoms of cat scratch disease can be noticeable after two to three days, but it is also possible that this lasts for two months. Therefore, after such a long time, the cat bite is often no longer suspected as a trigger. Possible symptoms include the cat scratching or biting, even though it may have healed. Red pustules or papules in the area of the wound as well as swollen and inflamed, sometimes painful lymph nodes on the armpits or neck are also signs of the disease. Possible accompanying symptoms may be flu-like symptoms, for example, fever, headache, aching limbs, sore throat and abdominal pain,chills, nausea and vomiting. In poor health or with a weakened immune system, for example in the context of an HIV infection or AIDS, the normally harmless cat scratch disease can result in blood poisoning, meningitis or heart valve inflammation. Therefore, caution is advised for people in poor health or with underlying diseases.

Diagnosis and course of the disease

Since the symptoms of cat scratch disease are often very different and can occur just as in other diseases, the medical professional must know the development of the disease. Also crucial is, of course, whether there are cats in the household. Furthermore, a blood test is performed. If the body has come into contact with the pathogen, it forms specific antibodies against the bacterium, which can be detected in the blood. By means of a blood sample, the pathogen can also be cultured, which takes a few weeks. Subsequently, an unambiguous result is possible. If the diagnosis is difficult, tissue can also be taken from a swollen lymph node to determine the disease with certainty. In most cases, cat scratch disease is harmless.Only rarely do complications arise when the bacteria attack the heart, bones or lungs, for example, and cause inflammation here. If the pathogens multiply too much in the blood, this can lead to blood poisoning and anemia, which is life-threatening and must be treated in a hospital intensive care unit.

Complications

In most cases, cat scratch disease is diagnosed at a very late stage. This disease can also show the first symptoms only after several months, so in most cases there is also a delay in treatment. As a rule, the affected person suffers mainly from pain caused by the bite or scratching of the cat. Papules and pustules form on the body. The affected regions may become swollen and painful. It is not uncommon for those affected to continue to suffer from fever and fatigue. Symptoms similar to an ordinary flu also occur. In the worst case, however, blood poisoning occurs, leading to inflammation of the heart or brain. Patients also suffer from nausea, vomiting and chills. The daily life of the affected person is restricted and there is a reduction in resilience. Treatment of cat scratch disease is carried out with the help of antibiotics. This does not lead to further complications. However, these can occur if the patient is already suffering from a weakened immune system. In this case, the life expectancy may also be reduced if necessary.

When should one go to the doctor?

If people who are in a direct contact with cats show health changes, they should consult a doctor. In the case of sudden changes in the appearance of the skin, such as redness and a formation of poplars or pustules, a doctor is needed. If the first abnormalities appear a few days after contact with cats, a visit to the doctor is also necessary. If pain occurs, there is fever or increased body temperature and swelling on the body, a doctor should be consulted. If lymph nodes on the neck or in the armpits increase in size and sensitivity, this is considered an indication of illness and should be investigated. If flu-like symptoms occur, such as repeated vomiting, nausea or dizziness, a medical examination is necessary to determine the cause. Chills, abdominal pain, digestive problems, discomfort of the limbs, aching bones or head should be presented to a physician. If existing complaints spread or increase in intensity, a visit to the doctor is necessary. Fatigue, tiredness, a drop in usual performance and a feeling of illness should be evaluated by a doctor. In case of cat scratch disease, the symptoms often appear after a bite or a scratch on the skin. In addition to the signs described above, a visit to the doctor is necessary if the wound heals poorly.

Treatment and therapy

Since cat scratch disease is a bacterial infection, it can be treated well with an antibiotic if it is complicated or severe. This is usually taken for four weeks. If the disease is accompanied by flu-like symptoms, fever-reducing medication or painkillers may also be prescribed. However, in people with a strong immune system and no history of illness, medication is usually not necessary, because the symptoms in these individuals are mild and resolve on their own.

Outlook and prognosis

Healthy adults usually experience only mild flu-like symptoms in the form of headache, aching limbs, or mild fever, which do not require medical treatment. Those affected primarily suspect the presence of a mild flu-like infection and avoid going to the doctor. They use warm baths, cold compresses, ginger tea or rubbing with rubbing alcohol as home remedies to relieve the symptoms. An intact immune system can usually fight off an infection with the bacterial pathogens of cat scratch disease itself. A physician must always be contacted if the fever rises or there is an exacerbation of existing symptoms. Likewise, if there is a localized inflammatory reaction following a cat scratch or bite injury. In seniors, children or chronically ill persons, on the other hand, the immune system is not fully functional and usually unable to fight the infection itself.In order not to lose time, a doctor must be consulted immediately and medical treatment must be started. Especially in the case of children, it is important to teach them certain rules of conduct in dealing with the cat to prevent a recurrence of the disease. They should stay away from the cat in the presence of open wounds until the initial treatment with a band-aid and in no case let the cat lick the wound.

Prevention

As a preventive measure, after injury by cats, always clean and disinfect the wounds well. After contact, it is recommended to wash hands thoroughly with soap and water. Cats should also be reliably cleared of fleas on a regular basis. Vaccination is not currently available. In case of an acute underlying disease, it may be advisable to give the cat away temporarily if possible.

Aftercare

Cat scratch disease is treated acutely. Scheduled follow-up examinations are not encountered in everyday practice. After a one-time illness, the attending physician will point out preventive measures to prevent the recurrence of the typical symptoms. However, the patient bears personal responsibility for this. Thus, flea control is elementary important for cats. Sufficient hygiene after contact with pets is also imperative. In certain people, cat scratch disease triggers complications. The risk group includes people with a weakened immune system. In the worst case, life-threatening blood poisoning develops. Affected patients should completely avoid contact with pets because of the danger. However, this is not controlled by the attending physician. He communicates this after a first diagnosis. The patient himself is responsible for the implementation. There is no reason for a permanent treatment, which can be part of the aftercare. In most cases, spontaneous healing occurs. However, the patient can become reinfected at any time. A blood analysis allows an unambiguous diagnosis. In case of prolonged course, an antibiotic promises speedy relief. Animal owners must consistently adhere to the preventive measures described. This reduces the risk of infection. Instruction regarding appropriate preventive measures in everyday life replaces scheduled follow-up.

What you can do yourself

Feline sickness is a bacterial infection that has symptoms not dissimilar to those of a mild flu. In healthy adults with intact immune systems, medical treatment is usually not required. In most cases, those affected are not even aware that they have not simply caught a cold. Even those who have been injured by a cat and fear that they have been infected with feline disease can initially wait and see. Minor accompanying symptoms such as headaches and aching limbs or a slight fever can also be treated with over-the-counter medications without hesitation. However, a doctor should always be consulted if the symptoms worsen, especially if a high fever develops or the scratch or bite wound becomes infected. Caution is also advised for children and seniors, as the immune system of these groups of people is not yet or no longer fully functional. If a cat lives in the house and these persons show signs of cat sickness, they should not experiment with self-help measures, but should consult a doctor immediately. The same applies to people whose immune system is weakened due to an illness. The pathogens are also found in the saliva of the cat. To reduce the risk of infection, children should be taught that they can become ill if they allow the pet to lick bruised knees or other minor injuries.