Sand flea (Tunga spp.) infections in humans and domestic animals: state of the art.

Tungiasis is a parasitic disease of humans and animals caused by fleas (Siphonaptera) belonging to the genus Tunga. Two species, Tunga penetrans (L.) and Tunga trimamillata, out of 10 described to date, are known to affect man or domestic animals; the other eight are exclusive to a few species of wild mammals. Tunga penetrans and T. trimamillata originated from Latin America, although the first species is also found in sub-Saharan Africa (between 20 degrees N and 25 degrees S). Hundreds of millions of people are at risk of infection in more than 70 nations, mostly in developing countries. The second species has been reported only in Ecuador and Peru. Males and non-fertilized females of Tunga are haematophagous ectoparasites; pregnant females penetrate the skin where, following dilatation of the abdomen, they increase enormously in size (neosomy) and cause inflammatory and ulcerative processes of varying severity. The importance of Tunga infection in humans concerns its frequent localization in the foot, which sometimes causes very serious difficulty in walking, thereby reducing the subject's ability to work and necessitating medical and surgical intervention. Tungiasis in domestic animals can be responsible for economic losses resulting from flea-induced lesions and secondary infections. Because tungiasis represents a serious problem for tropical public health and because of the recent description of a new species (Tunga trimamillata), it seems appropriate to review current knowledge of the morphology, molecular taxonomy, epidemiology, pathology, treatment and control of sand fleas of the genus Tunga.

Tungiasis in the United States: a travel souvenir.

Tungiasis is a cutaneous infestation caused by the burrowing flea, Tunga penetrans. This infection typically results in the development of one or more wart-like fibrous papulonodules. The causative flea is endogenous to Central and South America, sub-Sarahan Africa and portions of India; consequently, tungiasis is rarely reported in North America. However, because of increasing air travel to and from endemic areas due to business and pleasure, it is imperative that this entity remain in the differential diagnosis when evaluating clinically suggestive lesions in a patient who also has a history of recent travel. We report a case of tungiasis in a 24-year-old Caucasian woman who presented with 7-week history of a non-healing, eroded nodule on the medial aspect of her left great toe. Significant history included travel to Tanzania during three months immediately prior to presentation. Following the presumptive clinical diagnosis of tungiasis, surgical removal of the flea and its contents was performed and the base of the lesion was curetted, without complication. The specimen was sent for histopathologic correlation which confirmed the diagnosis.

Upper eyelid localisation of Tunga penetrans.

PURPOSE: This report describes two cases of palpebral localisation of Tunga penetrans. METHODS: Two Congolese patients (a 17-year-old black man and a 12-year-old black girl) presented with a history of itching and oedema of the left upper eyelid. RESULTS: On inspection and slit lamp examination, the patients manifested the characteristic lesion of a white translucent papule with a central black pit. Scraping of the lesion revealed a gravid adult female flea, allowing the diagnosis of infection with the flea T. penetrans. After removal of the parasite, a complete local recovery occurred over a 1-week period with local application of tetracycline. CONCLUSION: With the increase in international travelling, it is useful to know that eyelid localisation of T. penetrans is possible.

Ocular leech infestation in a child.

PURPOSE: To describe a patient with manifestations of ocular leech infestation. METHOD: Case report. RESULTS: The ocular foreign body was identified as a leech, Limnatis nilotica, by parasitologic examination. The leech was extracted, and the patient began using topical antibiotic and cycloplegic agents. By the third day after extraction, the patient had no obvious symptoms or signs, except for a limited subconjunctival hemorrhage, and no epithelial defect on the cornea was observed. CONCLUSIONS: Ocular leech infestation should be considered in patients with a history of swimming in streams and lakes. Attention should also be given to ocular leech infestation in the differential diagnosis of ocular trauma with iris prolapse.

Tungiasis--a cause of painful feet in a tropical traveller.

Tungiasis is an ectoparasitosis caused by the impregnated female sand flea Tunga penetrans. It is endemic in certain resource poor areas around the world and imported infestations in travellers can lead to considerable morbidity. With the rise in international travel and immigration, the likelihood of physicians encountering such tropical skin infestations is rising. The ability of physicians to recognise tungiasis early will be immensely beneficial to patients. We describe a case of tungiasis where a traveller presented with painful foot lesions. The patient had returned to the United Kingdom 4 days previously after spending 4 weeks in the Pantanal region in Brazil. A literature review on this subject was undertaken in this article.

Tungiasis-related knowledge and treatment practices in two endemic communities in northeast Brazil.

BACKGROUND: Tungiasis, caused by the sand flea Tunga penetrans, is highly prevalent in many resource-poor communities in sub-Saharan Africa, Latin America and the Caribbean. Studies on knowledge and treatment practices related to tungiasis in affected populations are virtually nonexistent. To fill this gap, we performed a study in two resource-poor communities in northeast Brazil where this parasitic skin disease is highly prevalent. METHODOLOGY: Structured interviews were realized in a representative sample of household leaders in an urban slum in Fortaleza, capital of Ceará State (northeast Brazil), and in a traditional fishing village 60 km southeast of the city. RESULTS: Two hundred ninety household leaders were interviewed in the urban slum and 136 in the fishing village. Knowledge about the etiological agent of tungiasis and its transmission was high in both communities: 90% knew the flea as the etiological agent of tungiasis. Transmission of tungiasis was thought to be related to sandy soil (72% and 84% in the urban slum and in the fishing village, respectively), presence of animals (52% and 59%), walking barefoot (5% and 23%), and with the presence of garbage littering the area (23% and 21%). Surgical extraction of embedded sand fleas using unsterile sewing needles was the most commonly treatment applied (97% and 96%). In addition, a variety of topical products and medical ointments was used. Mothers were almost exclusively responsible for treatment and knowledge transfer to the next generation. The health sector neither provided health education nor treatment. CONCLUSIONS: In communities of low socio-economic status in northeast Brazil, knowledge on tungiasis was high, but individuals did not follow appropriate treatment. A reduction of intensity of infestation, bacterial superinfection and associated morbidity is feasible with minimum support from the health sector, such as supplying hypodermic needles and disinfectants to mothers, and targeted health education.

Revision on tungiasis: treatment options and prevention.

The parasitic skin disease tungiasis occurs in many resource-poor communities in Latin America, the Caribbean and sub-Saharan Africa. The sand flea, Tunga penetrans, most commonly penetrates into the skin of the feet. Many individuals harbor a large number of embedded parasites and show significant morbidity. Standard treatment consists of surgical extraction of the flea and application of a topical antibiotic. There are no drugs available with proven effectiveness. Clinical trials performed in the last few years did not show very promising results. Thus, surgical extraction still remains the treatment of choice in patients with a low parasite load, such as tourists returning from endemic areas. Probably the best approach to reduce tungiasis-associated morbidity in heavily affected individuals is the application of a repellent to prevent the penetration of sand fleas. In the future, we should see new exciting data on the biology, epidemiology, therapy and control of tungiasis.

External ophthalmomyiasis caused by Dermatobia hominis. A retrospective study of nine cases and a review of the literature.

PURPOSE: To report nine cases of external ophthalmomyiasis caused by Dermatobia hominis. METHODS: Retrospective, non-comparative, interventional case series. Participants consisted of patients (n = 9) presenting at Cayenne Hospital between 1968 and 2003. The location and number of larvae, the larval stage, and the medical and surgical procedures applied were studied in each case. RESULTS: Seven patients had palpebral myiasis (including one with three larvae) and two had conjunctival myiasis. Every patient had palpebral oedema. The larval respiratory pore was located on the palpebral skin or free margin or on the conjunctiva. Movements were present within the lesion in at least three patients. Petroleum ointment or ivermectine solution was used in at least four patients to smother or kill the larvae. Extraction under local anaesthesia was possible in six patients, while three required general anaesthesia. CONCLUSION: Several larvae may be present in a patient. Topical ivermectine may help to kill the larvae before extraction is attempted.