What Is Dracunculiasis?

The medina dragon nematode Dracunculus medinensis is the only nematode that is mainly transmitted by drinking water and belongs to the genus Nematode. By 1995, the global elimination of guinea worms was the goal of the International Decade for Drinking Water Supply and Sanitation (1981-1990), and the World Health Assembly also formally established this goal in 1991. The implementation of this plan has greatly reduced the number of cases. There were 3.3 million patients worldwide in 1986, 625,000 in 1990, and less than 60,000 cases in 2002, and only 3,190 cases in 2009. And it happens mainly in Sudan. At present, guinea worm disease is limited to countries in sub-Saharan Africa.

The adult is shaped like a thick white line with a blunt front end.

Distributed in India, Pakistan, Afghanistan, Indonesia, Turkey, Iran, Nigeria, Ghana, the former Soviet Union, Mauritania, Guinea, Cameroon, Uganda, Ethiopia, New Guinea, Canada, the United States, the Caribbean Islands, Brazil, China, etc. ^[2]

The main pathogenic effect of this worm is that the female worm migrates to the skin, making the skin scleroderma and lumps appear; the released larvae can cause

Check for typical blisters on the skin; after the blisters break, check the larvae by placing a little water on the wound, taking a small amount of liquid from the surface of the wound onto a glass slide, and checking the active larvae under low magnification; surgery is also available Take the adults from the mass or take a liquid smear from the mass and inspect the larva under a microscope. Obtaining the extended females from injury 13 is the most reliable basis for diagnosis, but it must be distinguished from the subcleft parasitoid. X-ray examinations are helpful in diagnosing calcifications in the host. Immunological tests, such as intradermal tests, IFA or ELISA, can be used as adjuvant diagnosis. Eosinophils are common on blood tests.

Infected larva migrates and develops in the body, the female migrates to the subcutaneous tissue, and a string-like induration or mass can appear around the body. When the female migrates to the skin, it releases a large number of metabolites and produces the first stage larva. Can cause a strong allergic reaction of the host, which can cause papules on the skin surface of patients, and gradually develop into blisters, pustules, cellulitis, etc. The common parts are the lower ends of the legs and the feet, and the blisters are accompanied by local itching and severe burning pain The blisters were sterile yellow liquid, and a large number of macrophages, eosinophils and lymphocytes were seen under the microscope. There may also be systemic symptoms such as urticaria, diarrhea, fever, dizziness, and nausea. A pregnant female that cannot migrate to the skin can cause a sterile cystic fluid abscess at the site of the worm's retention. In addition, if the worm invades the nervous system, it can cause paralysis, and can affect the eyes, heart, and urogenital system, causing diseases such as inflammation.

After the female worms in the deep tissues of the body die, they gradually become calcified, which can cause inflammation of adjacent joints. Denatured worms can also release a large amount of antigen, which induces a sterile cystic fluid abscess. A case of a 12-year-old boy from Anhui reported in 1995 in China was under the skin of the left abdominal wall. A fragment of the medina dragonworm female was removed from the lump during surgery. The abscess was healed soon after surgery.

Larva inspection: When the blister is ruptured, place it on the wound with a little cold water, take a liquid smear on the wound surface to check, and see the active larva under the low magnification to confirm the diagnosis. You can also take adult worms from the lump or take liquid smears from the lump for microscopic examination of the larvae. Obtaining females that protrude from the wound is the most reliable basis for diagnosis, but it must be distinguished from the subcutaneous parasitic fissure. Immunological tests, such as intradermal tests, IFAT or EI_ISA can be used as adjuvant diagnosis. Increased eosinophils in blood tests ^[3]

This disease is a zoonotic disease

Mainly endemic in Africa (13 countries in sub-Saharan Africa). The prevalence varies widely from place to place, with almost all residents being infected in some places; few in others, mainly young people ^[5]

In April 1981, the Inter-Agency Steering Committee for the Cooperative Action of the International Decade for Drinking Water Supply and Sanitation (1981-1990) proposed the elimination of guinea worm disease as an indicator of the success of the Decade. In the same year, the World Health Assembly, the WHO's decision-making body, adopted a resolution (WHA34.25) recognizing that the International Decade for Drinking Water Supply and Environmental Sanitation presents opportunities to eliminate guinea worm disease. This led WHO and the United States Centers for Disease Control and Prevention to develop strategic and technical guidance on eradication activities.

The Carter Center was involved in the fight against the disease in 1986, and in collaboration with WHO and UNICEF, has been at the forefront of eradication activities ever since. In order to make a final effort, the World Health Assembly in 2011 called on all Member States with endemic guinea worm disease to accelerate the spread of the disease and carry out national surveillance to ensure that guinea worm disease To be destroyed.

Medina worms bring disease (5 photos)