Bath dermatitis

The Bath dermatitis was first described in the 1920s. Today it is widespread especially in North America and Central Europe. It is considered a harmless skin disease.

What is bath dermatitis?

Bathing dermatitis is caused by the larvae of a suction worm. This gets into the water through the worm-infested droppings of water birds, mainly ducks.
© Jürgen Fälchle - stock.adobe.com

The bath dermatitis, too Cervical dermatitis called, is caused by larvae. These multiply especially in the warm months such as June to September. Cercaria prefer water temperatures around 24 degrees. The infestation of humans happens only by mistake. The actual hosts of the larvae are ducks and water birds.

If there is contact, the first tingling or slight itching occurs after just 10 minutes. These symptoms are among the primary symptoms. More follow with repeated contact with the larvae. Bathing dermatitis is unpleasant and bothersome, but it is neither dangerous nor does it require special treatment.

causes

Bathing dermatitis is caused by the larvae of a suction worm. This gets into the water through the worm-infested droppings of water birds, mainly ducks. The hatching larvae usually attack snails, which they then use as intermediate hosts and are released back into shallow water after a few weeks.

The new generation of these larvae re-penetrate the duck's skin and reproduce. Humans are not considered hosts and are more likely to be accidentally affected. The cercariae penetrate the human skin, but die within a very short time. At the first contact there are only slight reactions.

However, if there is repeated contact with the cercaria, the immune system recognizes them as an intruder. The immune system is now activated and the typical symptoms appear. There is no connection with the water quality. The risk of bathing dermatitis is greatly increased in waters where there are many ducks. For this reason, especially in bathing areas, ducks should not be attracted by feeding.

Symptoms, ailments & signs

With an initial infection with cercaria there are usually no symptoms. Occasionally, reddish wheals develop, which may be associated with a slight itchiness. In severe cases, pain can be added that is limited to the area of ​​inflammation and is described by those affected as throbbing and glowing. Allergy sufferers can suffer a shock reaction from the first contact with the suction worm larvae.

Anaphylactic shock manifests itself as shortness of breath, swelling and other symptoms, which always depend on the extent of the reaction. If the infection occurs again, a fever can occur, which manifests itself in the form of a racing heart, sweating, fatigue and other typical symptoms. More wheals and swellings form in the area of ​​the skin, which are mostly pressure-sensitive and flaky as the disease progresses.

If the pustules are scratched open, this can lead to infections. Furthermore, bath dermatitis can cause severe discomfort throughout the body. Typical accompanying symptoms are nausea, vomiting and dizziness. Normally, however, bath dermatitis does not cause any major symptoms or discomfort. The disease can be distinguished from other skin diseases on the basis of the noticeable skin changes and the direct occurrence after swimming in contaminated water.

Diagnosis & course

The diagnosis of bath dermatitis is usually based on the typical symptoms. In order to substantiate this, a microbiological examination of the water body concerned must be carried out.

A blood analysis can also provide information about possible bathing dermatitis. Antibodies against the larvae then show up in the blood. Since bathing dermatitis is harmless and often does not require any treatment, these complex examinations are usually unnecessary. The course and intensity of bathing dermatitis vary from person to person. Very sensitive people often react much more strongly.

Bath dermatitis can sometimes be associated with severe allergic reactions, shock, dizziness, sweating, fever and nausea. As a rule, however, swollen wheals (diameter 3-8 mm) and severe itching appear. The symptoms usually subside after 10 to 20 days without any consequences. The wheals that occur in bathing dermatitis should by no means be scratched as this can lead to infections.

Complications

As a rule, there are no further complications with bath dermatitis and the disease is harmless to humans. In most cases, the affected areas become itchy due to bathing dermatitis. The skin is very red in these areas and has small pimples that resemble a mosquito bite.

It is advisable not to scratch these areas on the skin, as this will only increase the itchiness and cause wounds and scars. Wheals or papules form. However, these are not dangerous and do not need to be treated by a doctor. The itching disappears after a few days, the remaining symptoms remain on the body for a few weeks and go away without any particular complications.

There are no further symptoms during bathing dermatitis, but it is relatively uncomfortable on the affected stelae and can limit the patient's everyday life during this time. Scratching the affected areas on the skin can lead to further infections and inflammations. However, in the case of bath dermatitis, these can also be treated relatively well with the help of antibiotics and will subside in a few days.

When should you go to the doctor?

Bathing dermatitis does not necessarily need to be treated by a doctor. As a rule, the symptoms subside after a few days and do not result in any complications. However, if severe itching and swelling occur that have not disappeared after 10 to 20 days at the latest, medical advice is recommended.

If you have a high fever and circulatory problems, you should see your family doctor directly. If the frequently occurring wheals open, the wound must be treated professionally. Otherwise, infection and inflammation can occur.

People with an allergy should see a doctor if they suspect bath dermatitis. The disease typically occurs after contact with ducks or geese. If symptoms of bathing dermatitis occur after bathing in waters where there are many ducks, it is best to contact your family doctor or a dermatologist. Further medical clarification is particularly recommended for people with allergies, skin diseases, children and pregnant women. After the rash has subsided, no further visits to the doctor are usually necessary.

Doctors & therapists in your area

Treatment & Therapy

Treatment of bath dermatitis is usually not necessary. The typical itchiness can be relieved by using nursing ointments or lotions. If it becomes too strong, antihistamines in tablet form and ointments containing cortisone can help.

Treatment with special drugs against parasites or antibiotics is not necessary, as the larvae die shortly after entering the human body. If severe allergic reactions occur, an emergency doctor should be called immediately.

Outlook & forecast

The prognosis of bathing dermatitis can be classified as extremely good. It is a temporary phenomenon on the skin that is normally not associated with any permanent impairment. The changes in the skin recede within a short time and the skin appears normal.

The ingested larvae on the skin cannot harm the human organism as they are completely harmless to humans. For this reason, medical care or therapy is not necessary. The usual washing of the body under clean water and with hygiene products or taking a shower are sufficient to achieve freedom from symptoms.

In rare cases, an allergic reaction of the organism occurs due to the influencing factors. This should be examined by a doctor and, if necessary, treated medically. Even then, the person affected is completely symptom-free within a few days. If the patient gives in to possible itching on the skin, open wounds can form.

This gives germs and pathogens the opportunity to get into the organism. They can trigger secondary diseases that have to be diagnosed and treated individually. In severe cases, the affected person is at risk of blood poisoning. Without medical care, this can lead to a fatal course and thus to the death of the patient.

prevention

Prophylaxis against bath dermatitis is extremely difficult. Since cercaria are mainly found in shallow and water-plant-rich riparian zones, these should be avoided if possible.

Cercaries prefer warmer water, so swimming in cold water is advisable. Applying sunscreen lotion also provides light protection. Always take off your swimwear after swimming and dry it off thoroughly. This will remove possible parasites from the skin. If there are already vacancies, do not scratch them.

No effective and ecologically justifiable control method is known to date against cercaria. In the case of bathing lakes and swimming ponds, feeding ducks should be avoided at all costs. If the pond at home is also used for swimming, it is advisable to remove dead plant remains and snails with a landing net. This noticeably minimizes the risk of infection.

Aftercare

Bathing dermatitis is an acute and unproblematic skin change. Larvae penetrate the skin and die after a short time. Medical care is unnecessary. It is usually sufficient to dry yourself off well after bathing and apply simple lotions and ointments to the affected areas.

There is no reason for further follow-up care. As a preventive measure, patients should rather stay in deep water. The larvae prefer to live in shallow areas near the shore. Complications only arise when contact triggers an allergic reaction. In this case, patients should see a doctor. This can make a diagnosis based on the antibodies in the blood.

A microbiological examination of the water is just as useful, but is rarely done because of the effort involved. Sometimes wheals remain on the surface of the skin. Those affected should not scratch them, otherwise infection can follow.

The topic of aftercare is therefore relatively inexpensive with bath dermatitis. Since the disease is usually completely unproblematic, it is unnecessary outside of an allergic reaction. At most, those affected can avoid bank areas with the corresponding larvae. Infection is always possible. Immunity does not build up after healing.

You can do that yourself

Since the infestation, also known as cercariae dermatitis, can only take place in contaminated waters, prevention is the best way to help yourself. Anyone who regularly bathes in lakes, ponds or slow-flowing rivers should observe some precautionary measures. The actual hosts of the sucking worm larvae are water birds.

When bathing, places with a high concentration of ducks, swans and other water birds should therefore be avoided. The larvae also stay mainly in the flatter and therefore mostly warmer bank areas of the water, which is why these areas should be left quickly when swimming.

The use of waterproof sunscreen can prevent the larvae from entering the human body. A thorough shower and vigorous toweling with a towel can remove larvae that are still loose on the skin. Swimwear should always be changed quickly, as larvae can hide here too.

If an infestation has occurred, it is not dangerous in itself, but is accompanied by very severe itching, especially if it is a second infestation. Antihistamines from the pharmacy, which are offered as drops, creams or gels, help against this.

Patients should never scratch the itchy wheals to avoid secondary infections. Scratched wheals should be disinfected, treated with zinc ointment and then covered with a plaster.