Chigger Research Articles

The prevalence and association with health-related quality of life of tungiasis and scabies in schoolchildren in southern Ethiopia.

BackgroundThe prevalence of skin disease in low and middle income countries is high and communicable skin diseases are a significant public health problem. Tungiasis is an ectoparasite infestation caused by the flea Tunga penetrans, which has a widespread geographical distribution. Tungiasis causes painful skin lesions and may affect activities of daily living.ObjectiveWe wished to determine the prevalence and impact of tungiasis and scabies in schoolchildren in southern Ethiopia.MethodsA cross-sectional study was performed in which students were examined by dermatologists and the skin disorders recorded. Individuals with pyogenic skin infections, scabies and tungiasis were also invited to complete the Children’s Dermatology Life Quality Index.ResultsThere was a high burden of skin disease amongst this cohort with more than 40% having an ectodermal parasitic skin disease. The majority of these were due to tungiasis. Tungiasis was evident in more than a third of children and was associated with onychodystophy. There was a significant association between wearing “closed” footwear and a greater number of tungiasis lesions but not tungiasis per se. Dermatophyte infections, acne and plantar maceration secondary to occlusive footwear were also common.Scabies and tungiasis appeared to have a significant negative effect on quality of life.ConclusionTungiasis is highly prevalent in schoolchildren in the part of Ethiopia where the study was conducted and is associated with a deleterious effect on quality of life. The role of footwear in both preventing and possibly exacerbating cutaneous ailments in this setting requires further study.

Control of Tungiasis in Absence of a Roadmap: Grassroots and Global Approaches.

Tungiasis is a tropical skin disease caused by the sand flea Tunga penetrans. It inflicts misery upon tens of millions of people, mostly children, across Central and South America and sub-Saharan Africa, and yet there is no globally accepted roadmap for its control. Here we review how research in the last 15 years has developed control methods and report on new grassroots and digital mapping approaches. Treatment is now possible with a two-component dimethicone, used for the treatment of headlice in Europe, Asia and Canada, but not yet available in most tungiasis-endemic areas. Prevention is possible through the daily use of repellents based on coconut oil. A Kenyan coastal community has successfully controlled tungiasis using a neem and coconut oil mix produced locally to treat cases, combined with spraying floors with neem solution and distributing closed shoes. Development of affordable hard floor technology is underway, although not yet widely available, but is a priority to control off-host stages in the floors of homes. A new web-based digital mapping application will enable researchers and health officials to collaborate, share data and map the prevalence of tungiasis. We conclude that tungiasis can be controlled through a multi-disciplinary, One Health approach.

High intensity of Tunga penetrans infection causing severe disease among pigs in Busoga, South Eastern Uganda

BackgroundTowards the improvement of stakeholders’ awareness of animal tungiasis, we report 10 unusual severe clinical cases of pig tungiasis which were associated with very high infection intensities of T. penetrans in an endemic area.ResultsMorbidity of ten pigs with high sand flea intensities detected during high transmission seasons in an endemic area in Busoga sub region, Uganda is described in detail. The cases of pigs presented with a very high number of embedded sand fleas (median = 276, range = 141–838). Acute manifestations due to severe tungiasis included ulcerations (n = 10), abscess formation (n = 6) and lameness (n = 9). Chronic morphopathological presentations were overgrowth of claws (n = 5), lateral deviation of dew claws (n = 6), detachment (n = 5) or loss of dew claws (n = 1). Treatment of severe cases with a topical insecticidal aerosol containing chlorfenvinphos, dichlorvos and gentian violet resolved acute morbidity and facilitated healing by re-epithelialisation.ConclusionsThe presentations of tungiasis highlighted in this report show that high intensities of embedded T. penetrans can cause a severe clinical disease in pigs. Effective tungiasis preventive measures and early diagnosis for treatment could be crucial to minimize its effects on animal health.

Treatment of tungiasis with a two-component dimeticone: a comparison between moistening the whole foot and directly targeting the embedded sand fleas

BackgroundTungiasis (sand flea disease) is caused by the penetration of female sand fleas (Tunga penetrans, Siphonaptera) into the skin. It belongs to the neglected tropical diseases and is prevalent in South America, the Caribbean and sub-Saharan Africa. Tungiasis predominantly affects marginalized populations and resource-poor communities in both urban and rural areas. In the endemic areas, patients do not have access to an effective and safe treatment. A proof-of-principle study in rural Kenya has shown that the application of a two-component dimeticone (NYDA®) which is a mixture of two low viscosity silicone oils caused almost 80% of the embedded sand fleas to lose their viability within 7 days.MethodsIn this study we compared the efficacy of two distinct modes of application of NYDA®; one targeted application to the area where the parasite protrudes through the skin and one comprehensive application to the whole foot.ResultsIndependent of the two modes of application, the dimeticone caused more than 95% of embedded sand fleas to lose all signs of viability within 7 days. The targeted application killed embedded sand fleas more rapidly compared to when the whole foot was covered. The proportion of viable lesions at day two were 7.0 versus 23.4% (p < 0.01) and at day five 3.9 versus 12.5% (p < 0.02).ConclusionsOur findings suggest that the dimeticone could provide a safe and effective treatment for tungiasis in areas with difficult access to health care.Trial registrationISRCTN ISRCTN74306878

Trombiculiasis in domestic goats and humans in the state of Maranhão, Brazil

Trombiculiasis is an infestation caused by larval mites (chiggers) of the family Trombiculidae. Here, we provide the first report on parasitism by the chigger species Eutrombicula alfreddugesi (Oudemans) and Eutrombicula batatas (Linnaeus) in goats and humans on farms in the state of Maranhão, northeastern Brazil. Severe itching and dermatitis caused by the chiggers' bites were seen. From a total of 779 examined goats, 214 of them showed clinical signs of infestation, as well as family members of three farms of the region. Most of the cases occurred during the rainy season, from March to September.

Scrub Typhus: An Emerging Threat.

Scrub typhus is caused by Orientia tsutsugamushi (formerly Rickettsia) and is transmitted to humans by an arthropod vector of the Trombiculidae family (Leptotrombidium deliense and L. akamushi). It is the most common re-emerging Rickettsial infection in India and many other South East Asian countries. In fact, scrub typhus is confined geographically to the Asia Pacific region, a billion people are at risk and nearly a million cases are reported every year. Scrub typhus appears particularly to be distributed in the tsutsugamushi triangle which is distributed over a very wide area of 13 million km2 bound by Japan in the east, through China, the Philippines, tropical Australia in the south, and west through India, Pakistan, possibly to Tibet to Afghanistan, and southern parts of the USSR in the north. Eschar is the characteristic lesion that starts as a vesicular lesion at the site of mite feeding. Later, an ulcer forms with black necrotic center and an erythematous border along with regional lymphadenopathy. Other features are fever, maculopapular rash starting from the trunk, and spreading to the limbs. It may affect the central nervous system, cardiovascular system, renal, respiratory, and gastrointestinal systems. Serious complication in the form of myocarditis, pneumonia, meningoencephalitis, acute renal failure, gastrointestinal bleeding, and even acute respiratory distress syndrome may develop. Tetracycline or chloramphenicol remains the main stay of therapy.

Optimal Control Techniques on a Mathematical Model for the Dynamics of Tungiasis in a Community

Tungiasis is a permanent penetration of female sand flea“Tunga penetrans”into the epidermis of its host. It affects human beings and domestic and sylvatic animals. In this paper, we apply optimal control techniques to a Tungiasis controlled mathematical model to determine the optimal control strategy in order to minimize the number of infested humans, infested animals, and sand flea populations. In an attempt to reduce Tungiasis infestation in human population, the control strategies based on personal protection, personal treatment, educational campaign, environmental sanitation, and insecticidal treatments on the affected parts as well as on animal fur are considered. We prove the existence of optimal control problem, determine the necessary conditions for optimality, and then perform numerical simulations. The numerical results showed that the control strategy comprises all five control measures and that which involves the three control measures of insecticide control, insecticidal dusting on animal furs, and environmental hygiene has the significant impact on Tungiasis transmission. Therefore, fighting against Tungiasis infestation in endemic settings, multidimensional control process should be employed in order to achieve the maximum benefits.

Tetanus of the Child after Extraction of &amp;lt;i&amp;gt;Tunga penetrans&amp;lt;/i&amp;gt; in Brazzaville: One Case

Tetanus has become rare even exceptional in the West. On the contrary, it is common in developing countries such as Congo because of low immunization coverage. Its diagnosis, which is essentially clinical, is easy but necessitates a fine semeiological analysis under certain circumstances. We are reporting here a case of tetanus involving an 8-year-old unvaccinated, indigenous aboriginal boy that was caused by the extraction of a Tunga penetrans. The symptomatology of abdominal contractures led to an exploratory laparotomy. The evolution was favorable.

The presence of parasitic mites on small mammals in Algonquin Provincial Park, Ontario, Canada

Here we identify, for the first time, a generalist orange parasitic mite found on multiple small-mammal species in Algonquin Provincial Park, Ontario, Canada. Results from 18S rRNA sequencing suggest that these mites may belong to the family Trombiculidae (Acari: Trombidiformes), although morphological and additional genetic analyses are needed to confirm this identification. The presence of these mites was associated with lower body condition in North American red squirrels (Tamiasciurus hudsonicus (Erxleben, 1777)), suggesting that these mites may be a detriment to fitness in small mammals or are more successful when targeting individuals in poorer condition. A lack of sex-biased host infection, emergence dates outside of the host reproductive season, and stability of mite prevalence across study years indicate mite population dynamics may be driven predominantly by factors external from host status, such as climatic conditions or habitat preference. Future research should focus on providing additional reliable identification of these mites, as well as broadening our knowledge on their range, pathogenicity, and impact on small-mammal community dynamics.

An unusual cause of simultaneous bilateral spontaneous pneumothorax.

Scrub typhus, a tropical febrile vector borne disease also known as “Tsutsugamushi disease”, is caused by Orientia tsutsugamushi, a gram negative obligate intracellular slow growing bacteria. The infection is transmitted by the bite of larval stage (chiggers) mites belonging to the family Trombiculidae. The disease is transmitted from larval stage mites to rats, where humans are an accidental host. The name scrub typhus is derived from the prevalence of the mites in areas of heavy scrub vegetation. Here we report a case of a young man with primary ciliary dyskinesia presenting with bilateral pneumothorax following Scrub typhus infection.

Scrub Typhus in Chile

Scrub typhus, caused by Orientia tsutsugamushi, is an endemic zoonotic infection transmitted by the larvae (“chiggers”) of trombiculid mites in what

Prevalence and clinical aspects of tungiasis in south-west Nigerian schoolchildren

Tungiasis is highly prevalent in resource-poor communities in sub-Saharan Africa, but studies among schoolchildren are scanty. We assessed prevalence, parasite load and clinical aspects of tungiasis in schoolchildren in south-western Nigeria. A total of 545 schoolchildren was examined. Of these, 133 (24.4%; 95% CI, 20.9-28.2%) were infested with Tunga penetrans Boys showed a higher prevalence than girls (31% versus 18%, P < 0.0001); in those infested, the median number of lesions was two, with no gender difference (2 boys, interquartile range, 1-4; 2 girls; interquartile range, 1-4; P = 0.34). The maximum number of 44 lesions was found in a 14-year-old boy. Desquamation was present in 90.2%, followed by erythema (54.9%) and oedema (43.6%); 54.9% showed any chronic pathology and more one-third nail deformations. Our study indicates that tungiasis is an important health problem in rural Nigerian schoolchildren. Sustainable interventions are required to control the disease in this and similar communities.

Chigger mites of the genus Ericotrombidium (Acariformes: Trombiculidae) attacking pets in Europe

Diversity of chigger mites causing trombiculiasis of domestic animals and humans in Europe is greatly underestimated. A number of reports on the attacks of “harvest mite” (Neotrombicula autumnalis) could be based on misidentified chiggers from other species and genera. In this study descriptions of two cases of trombiculiasis are presented, which constitute the first report on the pets’ parasitism by the chigger genus Ericotrombidium in Europe. The species Ericotrombidium ibericense is for the first time reported in Portugal as a causative agent of the trombiculiasis entailed extensive alopecic lesions and pruritus in a cat. Ericotrombidium geloti is for the first time reported as a cause of canine trombiculiasis in Crimea. Presence of other Ericotrombidium species on man and domestic animals is highly probable in countries of the Mediterranean basin.

A new genus and species of chigger mite (Trombidiformes: Trombiculidae) from Loxodontomys pikumche (Rodentia: Cricetidae) in Chile.

The family Trombiculidae is one of the most diverse and cosmopolitan (Walter et al. 2009). In Chile, the family Trombiculidae is represented by six genera associated with reptiles: Eutrombicula Ewing; Microtrombicula Ewing; Paratrombicula Goff & Whitaker; Whartonacarus (Brennan & Jones); Diaguitacarus Stekolnikov & González-Acuña and Proschoengastia Vercammen-Grandjean and two genera associated with rodents Chilacarus Webb, Bennett & Loomis and Poliremotus Brennan & Goff (Stekolnikov & González-Acuña 2015).

Tungiasis: diagnosis at a glance

A 22-year-old Japanese woman presented to our hospital with a 10-day history of pain and a rash on her right fi rst toe 10 days after a 2-week trip to Uganda, where she had stayed within Manafwa district. Although she had worn shoes and socks during student fi eldwork she reported wearing sandals with no socks around the suburban guesthouse. On examination she had a yellowish-white nodule, 5 mm diameter, with a central black spot at the rim of her right fi rst toenail (fi gure). We suspected stage 3 tungiasis and excised the nodule under local anaesthesia, during which we saw several eggs (fi gure), and also gave a tetanus toxoid booster. Stereomicroscopy showed Tunga penetrans, body length 0·5 mm, with mature eggs (fi gure). At follow-up examination 7 days later the lesion was completely healed with no signs of secondary bacterial infection. Tungiasis is an ectoparasitic skin disease caused by the female sand fl ea T penetrans, which is endemic to Central and South America, the Caribbean, and sub-Saharan Africa. The principal reservoirs of the fl ea are animals. Once inside the person, a tiny fl ea can grow up to a diameter of 10 mm within 1–3 weeks and leave hundreds of eggs. Tungiasis is an important health hazard in endemic areas, associated with long-term physical disability, immobility, and chronic pain, and self-excision can lead to life-threatening secondary bacterial superinfections such as tetanus and the transmission of blood-borne infections. Although surgical excision has been established as an eff ective treatment, another option is topical dimethicone to reduce the potential for adverse events. Tungiasis is a dynamic zoonotic disease that can be classifi ed under various stages, making diagnosis challenging as signs and symptoms change during the developmental stages of the embedded female sand fl ea. Travellers should be educated about the importance of wearing closed shoes and socks at all times during their visits to endemic areas.

Tungiasis-associated morbidity in pigs and dogs in endemic villages of Uganda.

BackgroundTunga penetrans (Insecta, Siphonaptera, Tungidae) causes severe morbidity among heavily infected humans and animals in Latin America and sub-Saharan Africa. The clinical pathology of tungiasis in animals has never been studied systematically.MethodsThis was a cross-sectional study conducted between January to March 2015, aimed at describing tungiasis-associated clinical pathology in 121 and 20 T. penetrans-infected pigs and dogs, living in nine and five endemic rural villages respectively located in Bugiri District, Busoga, Uganda.ResultsThe parasite load of infected animals ranged from one to 246 (median 8) and one to eight (median 2) in pigs and dogs, respectively. In pigs 99.3 % and in dogs 100 % of the lesions were located on feet. In pigs, hind legs were significantly more affected than front legs (90.9 % vs. 57.9 %; p = 0.002) and also had more lesions than the front legs (median 5 vs. 1; p = 0.0001). However, in dogs localization of lesions between front and hind legs never differed significantly (front, 50 % vs. hind, 65 %; p = 0.51) and so were the number of lesions (median front = 0.5 vs. median hind = 2; p = 0.7). Acute and chronic clinical pathology coexisted. The most common disease manifestations in pigs were hoof wall erosions (68.6 %), tissue necrosis of hoof wall and skin (66.1), pain at infection sites (47.9 %), hoof deformity (45.5 %), fissures (44.6 %) and edema (44.6 %). In dogs, tungiasis mainly presented with pain at attachment site (80 %), ulcers (55 %), necrosis (30 %) as well as hyperemia and edema (both 15 %). One pig had lost dew claws while two had loose detaching claws. Despite a lower number of sand fleas, a higher proportion of infected dogs (20 %) than pigs (5.8 %) exhibited functional limb use difficulties (p = 0.05).ConclusionsThe pattern of clinical manifestations in pigs and dogs were very similar to those reported from affected humans and rats. The important morbidity associated with animal tungiasis makes the disease a serious veterinary health problem in sub-Saharan Africa warranting treatment and control for optimal animal production.

Two Severe Cases of Tungiasis in Goat Kids in Uganda.

Tungiasis ensues from the penetration and burrowing of female sand fleas (Tunga spp.; Siphonaptera: Tungidae) in the skin of mammals. There are few case reports of severe tungiasis in goats and in these cases the Tunga species were not in most cases clearly identified. Two cases of severe tungiasis caused by Tunga penetrans in goat kids from tungiasis-endemic rural Uganda are reported. These are the first severe cases of tungiasis in goats reported from outside South America.

A Rapid Appraisal of the Efficacy of Sodium Carbonate in the Management of Tunga penetrans Infestation at Uuna Primary School in Karemo Division, Siaya District, Kenya

The study assessed the efficacy of Sodium carbonate in removing jiggers. The 2007 study purposively sampled 27 pupils in class five to eight out of 68 jigger victims at Uuna primary school that had an upper primary pupil population of 275. The upper primary section was purposively selected because the school offered holiday teaching for these pupils. The whole school had 762 pupils. Structured questionnaires were administered to the purposively sampled pupils. Frequencies and percentages were calculated. Approximately 68 (8.9%) of the total student population at the school were jigger infested for 2 weeks to 4 months. Infestation was higher in class five (11%) reducing to 1% in class eight with twenty two percent children not wearing shoes. On dissolving 50 gm/litre of Sodium carbonate in warm water and applying it to the infested feet, 19 (70%) pupils had 100% jigger extraction, within 15 to 20 minutes. This was the first study showing Sodium carbonate as an effective local chemical alternative in removing jiggers.

Infection with the Sand Flea Tunga penetrans (Tungiasis) in a Traveller Returning from Cameroon, Africa

Infection with the Sand Flea Tunga penetrans (Tungiasis) in a Traveller Returning from Cameroon, Africa

Prevalence and risk factors associated with tungiasis in Mayuge district, Eastern Uganda

IntroductionTungiasis is an endemic but neglected health problem in Uganda especially in resource poor communities. It is largely affecting rural communities in the Eastern, West Nile and Central regions. This study assessed prevalence and risk factors associated with tungiasis in Mayuge district, Eastern Uganda.MethodsThis was a cross sectional study that used a semi-structured questionnaire and observational checklist to collect quantitative data from 422 households in 12 villages. Prevalence of tungiasis was defined as presence of Tunga penetrans in the skin of any household member at the time of data collection.ResultsThe prevalence of tungiasis was 22.5%. However, a big percentage 41.5% of households were reported to have had T. penetrans in the previous month while 49.5% had T. penetrans for more than one month. Majority (90.5%)of the participants used a pin, needle, or thorn to remove sand flea from infected body parts. Having dirty feet (AOR 3.86, CI (1.76-8.34)), dirty clothes (AOR 3.46, CI (2.00-5.97)), cracked house floor (AOR =6.28, CI (3.28-12.03)), dirty floor (AOR 3.21, CI (1.38-7.46)), littered compounds (AOR= 2.95, CI (1.66-5.26)) and rearing cattle (AOR 2.38, CI (1.28-4.45)) were associated with tungiasis. However, practicing preventive measures (AOR 0.51, CI (0.29-0.90)) was found protective for disease.ConclusionTungiasis is still a prevalent health problem in rural communities in Eastern Uganda due to a number of individual (host) and environmental factors. There is need to increase awareness regarding improvement in sanitation and hygiene to enable communities’ implements interventions for prevention of T. penetrans.