TUNGIASIS- A neglected parasitic infestation


 TUNGIASIS- A neglected parasitic infestation
A skin infestation caused by burrowing flea named T. penetrans belongs to order Siphonaptera.  It is an Infectious disease. Tungiasis is an inflammatory skin disease found in the tropical parts of Africa, the Caribbean, Central and South America, and India. Lesions caused by this are characterized by a white patch with a black dot in the center. The infestation of Tungiasis can rapidly affect an entire home, school or community. The flea is highly contagious and is difficult to eradicate. Children that are infected become outcasts because of the shame associated with this disease. They cannot run, play, or concentrate in class because of the pain.
    Jiggers are easily transmitted among the poor living in urban slums and rural societies. It is endemic in developing countries in the tropics, mainly in the resource-poor people of South America, the Caribbean and subsaharan Africa. The disease only periodically affects travelers to endemic regions in South America and Africa; however persons living in native communities commonly suffer from serious infestation. In tropical regions, Tungiasis caused by T. penetrans is a human disease directly linked to the parasitism of humans by fleas. Though, to many of the general population, the insidious attacks by fleas on people and domestic animal causes irritation, blood loss, and severe discomfort are equally important as disease threat. The aim of this paper was to review the existing literature concerning Tungiasis.
Epidemiology of the disease:
 Tungiasis is present globally in more than 88 countries with varying degrees of incidence and prevalence. Flea-borne infections are emerging or re-emerging throughout the world, and their incidence is on the rise. This parasitic disease is of special community health concern in extremely prevalent regions such as Nigeria, Kenya, Cameroon, Trinidad, Tobago, and Brazil, where its prevalence, mostly in poor peoples, has been recognized to reach 50%. T. penetrans is distributed in tropical and subtropical regions of the world, including Mexico to South America, the West Indies and Africa. The fleas normally occur in sandy climates, including beaches, stables and farms.
Biology and transmission of intriguing parasite:
The off-host part of the sand flea cycle is similar to other Siphonaptera species. Expelled eggs fall to the ground and develop into larvae, pupae, and adults in the immediate surroundings. Larvae hatch after 1 to 6 days (mean 3–4 days) and pupation takes place after another 5–7 days. The formation of adult fleas inside the puparium needs 9–15 days. Under favorable conditions, an adult sand flea will emerge about 20 days after an egg has “touched down”.
Three life cycles of the sand flea coexist in a tropical environment: a human, a domestic animal, and a sylvatic cycle. These cycles overlap, partially or totally.                                   
T. penetrans is one of the few parasites that can maintain its whole life cycle in a person's sleeping quarter. Eggs expelled when a person sleeps will fall directly down to the floor or fall later, when the bed is made. The eggs may then be transferred to crevices and holes when the floor is swept. The larvae feed on the ever-present organic material. Eventually, adults emerging from pupae adhere to and penetrate into the skin, when a person places his or her naked feet on the ground. If people have to sleep on the floor, sand fleas will also penetrate parts of the body other than the feet.
Clinical Findings:
The initial burrowing by the gravid females is usually painless; symptoms, including itching and irritation, usually start to develop as the females become fully developed into an engorged state. Inflammation and ulceration may become severe, and multiple lesions in the feet can lead to difficulty in walking. Secondary bacterial infections, including tetanus and gangrene, are not uncommon with Tungiasis. The initial sign of infestation by jigger flea is a minute black lesion on the skin at the site of entrance. The zone around the entrenched flea develops very irritating swelling leading to ulcerations, lymphangitis, and formation of pus. When the female fleas die, they rest embedded inside the host, repeatedly causing swelling and consequently secondary infections. If unnoticed, it leads to gangrene, auto-amputation of fingers, damage of toes, tetanus, or death.
Lack of self-confidence:
 The parasite causes pain and injury that can seriously impede activities and performance of many of life’s chores, making a person dependent on others. The ulcerations and auto amputation of the digits make the victims feel embarrassed of being in public places and may usually reduce their self-confidence.
Prevention and control:
Prevention approaches include, wearing closed shoes; keeping animals contained; wetting the floors within houses regularly; maintaining good personal hygiene. Daily check of the feet with immediate extraction of embedded fleas and subsequent disinfections of the lesion protect against complications. Administering antibiotics and applying insecticide will minimize the occurrence and impact of T. penetrans and secondary microbial complications.
Mechanical extraction of flea by using sterile needle after cleaning area with antiseptic solution.
Disease perception and health seeking behavior:
Communities suffering from Tungiasis do not recognize Tungiasis as an important health threat, even with severe disease present in the many of the children. In fact, mothers rarely take children with overt lesions to primary health care centers; they seem to be ashamed because the presence of multiple Tungiasis lesions would indicate that they do not sufficiently care for their children. Physicians’ awareness of the disease is also deficient. As fleas are normally removed by the patient or a caretaker, and lesions are not brought to the attention of medical professionals, physicians consider Tungiasis to be nuisance rather than an important infection. Moreover, when complications arise at a later stage, this is seldom attributed to T. penetrans.
The presence of the jigger in the skin causes itching feeling, and in severe cases causes damage of nails, formation of ulcers, inflammation, suppuration, chronic lymphedema, sepsis and could be death. Jigger infestation affects the education of teenagers as they might be incapable to walk to school, join in regular learning activities. The ulcerations of the fingers due to severe Tungiasis make the sufferers feel ashamed of being in social places and it usually reduces people’s self-confidence. Jiggers infestation is likely to be increasing and causing livelihood of communities in developing countries. Therefore, new appropriate prevention and control approaches should be designed to mitigate the persistence of the disease (Tungiasis), particularly in vulnerable and poor communities.

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