Dracontiasis is the name given to a parasitosis in remission caused by the Medina or Guinea worm. The disease manifests about a year after consumption of infected tiny copepods by means of ulcers about the size of a pigeon egg that burst open on contact with water. The uterus of the nematode, which shows up in the ulcer along with its head end, also bursts open, releasing thousands of larvae.
What is dracontiasis?
Dracontiasis is the name given to a parasitosis caused by a nematode called medina or guinea worm. The pathogen requires generational interchange between humans or other mammals and a tiny copepod that lives in freshwater. Hygienic measures, especially with regard to observing certain hygienic standards when handling drinking water, have greatly reduced the disease in recent years. Infected copepods contain so-called L3 larvae of the worm, which corresponds to the last larval stage. After consumption by humans or another mammal, the larvae further develop into the female or male medina worm. Dracontiasis becomes visible about a year after ingestion of the L3 larvae, which have now developed into worms and mated. In the female specimens, thousands of larvae grow in her body. After they mature, the worms secrete a substance that causes the skin to form an ulcer about the size of a dove, which bursts open when it comes into contact with water, releasing the larvae into the water. The disease is visible only by means of the typical ulcers, in which the uppermost part of the worm is also revealed after bursting.
Causes
Dracontiasis is caused exclusively by the female medina worm (Dracunculus medinensis). The ulcers (ulcer) of dracontiasis, which have a typical circular shape, develop because of a secretion secreted by the female worm at the end of its head when the larvae in its uterus have reached the mature stage. The secretion of the nematode not only provides the typical shape of the ulcers. It also ensures that they burst open from the center when they come into contact with water. The worm, whose head end is then visible, releases thousands of its larvae in several spurts within two to three weeks whenever the ulcer comes into contact with water.
Symptoms, complaints, and signs
In the early stages, dracontiasis is asymptomatic. The first symptoms appear when the ingested larvae have developed into mature worms and the fertilized female nematodes move toward the target tissue. They cause unpleasant pain as they “migrate” in the connective tissue toward extremities such as the lower legs and feet. The subsequent formation of the ulcers is also associated with pain. The reddish swollen surrounding tissue of the ulcer itches and burns and makes an inflamed impression. It is at the same time very sensitive to pain. The substances released by the worm to create the ulcer can also cause allergic reactions that can lead to difficulty breathing, an itchy rash, or vomiting.
Diagnosis and course
A definite diagnosis can be made when a typical ulcer has formed and the head end of the white nematode is visible after the ulcer has ruptured. This means that about a year may have already passed since ingestion of the infected copepods. In addition to humans, other mammals can also be considered as intermediate hosts. The larvae from the copepod first enter the digestive tract – usually together with the drinking water. They are able to penetrate the intestinal mucosa and enter connective tissue. Here they grow into small male and longer female nematodes and mate. After mating, the male worm dies and becomes encapsulated by the surrounding tissue. The female worm continues to grow and gradually migrates to the subcutaneous connective tissue of the extremities, preferably the lower legs and feet. The female medina worm can reach a length of over one meter, and after maturing larvae in its uterus, near its head, it causes the skin of its host to form an ulcer, which bursts open upon contact with water, revealing the upper end of the worm. In the visible upper part of the worm is the uterus containing thousands of larvae in the first larval stage (L1). They are excreted in batches and released into the water.If left untreated, the female nematode dies after completion of larval birth. The ulcers regress unless one of the common secondary infections has formed there.
Complications
There are usually no complications or symptoms of dracontiasis in the first few months after infection. The patient is usually unaware that he or she has the disease. The pain occurs when the larvae have matured and are moving in the tissues. In this process, the patient suffers from pain, which occurs mainly in the extremities. There is also itching and burning and a severe rash on the skin in many cases. It is not uncommon for patients to suffer from permanent vomiting, which can greatly reduce the quality of life. Treatment is usually by removing the worm from the tissue. Usually, the worm is removed by a few centimeters each day, so the treatment can last for several months. During this time, the patient suffers from the symptoms described. Alternatively, surgical intervention may be performed. Life expectancy is not affected by dracontiasis. However, Dracontiasis may occur again in the life of the affected person. After successful treatment, there are no further symptoms or complications.
When should you go to the doctor?
There is no drug treatment available for medina worm infection. Since the parasite also dies if left untreated after the larval discharge has ended and the skin ulcers caused by the worm then usually heal, medical treatment for those affected is generally omitted in the risk areas. For Europeans, however, this is not an option. Since the worm reproduces very aggressively and there is a risk of infection for third parties, a doctor should be consulted immediately at the first suspicion of dracontiasis. However, the symptoms of the disease do not appear immediately, but usually only about a year after contamination. The female nematodes then migrate through the connective tissue after mating, causing pain, particularly in the lower legs and feet, for which no cause can be identified. Anyone who has spent time in a risk area should seek medical attention immediately if they notice such symptoms. The next step is the formation of ulcers, which can reach the size of pigeon eggs and are filled with thousands of larvae. At this point at the latest, those affected should consult a specialist, preferably a doctor of tropical medicine. If the disease is not treated, not only is there a considerable risk of infection for the social environment, but the ulcers caused by the worm can also become infected, which can lead to secondary infections.
Treatment and therapy
There is no known direct drug therapy to control the parasitic medina worm. A method used since ancient times to gently remove the worms is still widely practiced today. After the upper part of the worm shows inside the ulcer, the upper end is wrapped on a thin wooden stick – for example, a match – without tearing it off. The method requires some practice, skill and patience, because only about ten centimeters a day can be managed in this way. This means that the wrapping method can drag on to two or more weeks. As an alternative to the wrapping method, there is also the possibility of surgical removal of the worms. However, not all endemic areas have the necessary technical facilities, and for many of those affected, the cost of surgery exceeds their financial means. Even after an infection has been overcome, no immune protection is built up, so that a new infection can occur at any time.
Outlook and prognosis
The prognosis of dracontiasis is favorable in most cases. In approximately 50 percent of all sufferers, healing occurs without consequences after the medina worm has left the body. However, the worm produces itchy and painful blisters that provide an entry point for bacteria. Thus, various bacterial infections are possible, which can lead to subsequent defect healing. In some cases, tendons and joints located near such a blister are damaged. This damage is caused by joint inflammation and constant abscesses in the affected areas. As a result, the joints may stiffen.Furthermore, however, an infection with the media worm does not guarantee that no new infections will occur. The affected person can become infected again and again with the roundworm Dracunculus medinensis, because immunity against the worm is not built up. Thus, in drought-prone areas, new infections are constant when the population relies on unfiltered water from water collection points in the face of an unsafe drinking water supply. Unlike most of the population, the disease is usually fatal in newborns. In surviving infants, it causes severe health damage. Although the disease often heals without consequences in adulthood, it can also lead to severe sequelae in some cases. This is especially true if meningoencephalitis occurs as a complication of the infection.
Prevention
The best and most effective preventive measure is to follow simple hygiene measures when handling drinking water in the few remaining endemic areas. For example, filtering drinking water through a cheesecloth or boiling it is sufficient.
Follow-up
In most cases of dracontiasis, follow-up measures are very limited. In this case, patients depend on comprehensive examination and subsequent treatment to prevent further complications and discomfort. Therefore, the main focus in this disease is early detection and examination of the disease, so that there is no further worsening of symptoms. In most cases, dracontiasis can be treated relatively easily, and surgical intervention is not always necessary. After removal, the wound should be permanently cleaned to prevent re-infection. If surgery is necessary, it is recommended that the affected person rest after the procedure and not engage in any strenuous or physical activities. As a rule, the affected person may become ill again even after the dracontiasis has healed, so the trigger of this disease should be avoided at all costs to prevent re-infection. If the disease is detected early and treated quickly, the patient’s life expectancy will not be reduced. No further measures of follow-up care for dracontiasis are then necessary.
What you can do yourself
If Dracontiasis has been diagnosed, the most important action is to remove the worm quickly. In the case of less aggressive worms, those affected can perform the removal of the parasites themselves. To do this, the visible end of the worm is wrapped on a wooden stick without tearing off the worm. This procedure must be repeated daily until the entire worm has been pulled out of the body. The parasite can then be discarded and the procedure repeated on other ulcers. It usually takes several days to weeks to completely remove a medina worm. That is why it is indicated to have the treatment supervised by a doctor. If severe pain or itching occurs, some remedies from natural medicine can be used. Preparations with arnica or devil’s claw have proven effective, but homeopathic remedies such as belladonna can also be used. If the worm does not come off by itself, a doctor must be consulted. The parasite must then be surgically removed. For the patient, the procedure is usually not very stressful. After one to two weeks, the wound should have healed. Because of the increased risk of reinfection, regular checkups with a physician are indicated thereafter.
