Investigations on the biology, epidemiology, pathology and control of Tunga penetrans in Brazil. II. Prevalence, parasite load and topographic distribution of lesions in the population of a traditional fishing village

Management of very severe tungiasis cases through repeated community-based treatment with a dimeticone oil formula: A longitudinal study in a hyperendemic region in Uganda

Tungiasis (sand flea disease) is a neglected tropical disease that is endemic in Sub-Saharan Africa and Latin America. Tungiasis causes pain, mobility restrictions, stigmatisation and reduced quality of life. Very severe cases with hundreds of sand fleas have been described, but treatment of such cases has never been studied systematically. During a larger community-based tungiasis control programme in a hyperendemic region in Karamoja, northeastern Uganda, 96 very severe tungiasis cases were identified and treated with the dimeticone formula NYDA®. They were repeatedly followed-up and treated again when necessary. The present study traces tungiasis frequency, intensity and morbidity among these 96 individuals over 2 years. At baseline, very severe tungiasis occurred in all age groups, including young children. Throughout the intervention, tungiasis frequency decreased from 100% to 25.8% among the 96 individuals. The overall number of embedded sand fleas in this group dropped from 15,648 to 158, and the median number of embedded sand fleas among the tungiasis cases decreased from 141 to four. Walking difficulties were reported in 96.9% at the beginning and in 4.5% at the end of the intervention. Repeated treatment with the dimeticone formula over 2 years was a successful strategy to manage very severe cases in a hyperendemic community. Treatment of very severe cases is essential to control the spread and burden of tungiasis in endemic communities.

Prevalence and Infection Intensity of Human and Animal Tungiasis in Napak District, Karamoja, Northeastern Uganda

Tungiasis is an important but highly neglected cause of morbidity in resource-poor communities in Latin America and sub-Saharan Africa. Data upon which implementation of control measures can be based are scarce. Before piloting an integrated tungiasis control program in three parishes of Napak district, Uganda, a cross-sectional survey involving the systematic examination of humans and domestic mammals was implemented to establish the occurrence patterns of tungiasis. The study population was 5482 residents, of which 4035 (73.6%) participated in the study. The prevalence of tungiasis in humans was 62.8% (95% CI: 61.3-64.3%), with slightly more males than females affected (p = 0.01). Age-specific prevalence and intensity of human tungiasis followed an S-curve pattern, with children of 5-14 years and the elderly (≥60 years) being the most affected. Half of all lesions (50%) had been manipulated by sharp objects. The prevalence of tungiasis in animals was lower (14.2%, 95% CI: 10.9-18.0) than that of humans (p < 0.001). Animal tungiasis occurred in decreasing order of frequency in pigs (80%), dogs (24%), goats (16.3%), cats (8.1%) and sheep (4.9%). In conclusion, human tungiasis was highly prevalent but animal infections were comparatively few in the study area. Nevertheless, effective control measures should be based on One Health principles.

Protocol for a Randomized Control Trial for Tungiasis Treatment in Homa Bay County, Kenya: Dimeticone versus Sodium Carbonate

Tungiasis, a World Health Organization neglected tropical disease, is caused by the female sand flea. Most clinical trials for tungiasis use expensive or impractical drugs, which are difficult for residents to use. However, in western Kenya, communities successfully treat tungiasis with sodium carbonate. We hypothesise that the topical risk-difference of 5% sodium carbonate is no more than 10% non-inferior to dimeticone (NYDA^®) for tungiasis treatment. This is a protocol for a non-inferiority study, which will be randomised and with an observer-blinded control. The study will have two arms: 5% sodium carbonate and NYDA^®, one on each foot, and will take place at state primary schools in Homa Bay County, Kenya. Fleas identified among school children aged 8-14 years with sand-flea lesions will be enrolled in the study. For each participant, the viability of the embedded fleas, clinical signs including inflammation, and symptoms will be monitored for seven days after treatment. The proportion of dead fleas will be compared in the primary analysis. All adverse events will be monitored throughout the study period. We expect to identify the most effective treatment between sodium carbonate and NYDA^® for tungiasis, which can be adopted in the community.

Clinical and epidemiological survey of tungiasis in Madagascar

BACKGROUND

Tungiasis is a dermal parasitic infection, classified as a neglected tropical disease. Madagascar is one of endemic countries which have been committed for decades to control the tungiasis as a public health issue. Despite this medical importance, little is known about the prevalence and epidemiology of the disease in this country.

METHODS

A descriptive cross-sectional survey was performed in two endemic foci of Antananarivo and Toamasina.

RESULTS

In total, 2971 suspected individuals were surveyed. Of them, 643 individuals were excluded due to absence or refusing clinical examinations. Therefore, 2328 individuals with aforementioned criteria were clinically examined, 320 cases (13.7%) were found infected by Tunga penetrans. Of these 320 infected cases, 241 individuals came from rural regions against 79 from urban areas. The sex ratio of infected cases was 1.15 with an age average of 34.7 years old. Most of them were illiterate (185/320, 57.8%) with no habit of feet washing (210/320, 65.6%). The majority (198/320, 61.9%) inhabited in the houses constructed by falafa providing a suitable breeding location for Tunga ectoparasites. Based on clinical examination, most of the patients (298/320, 93.1%) had the lesions on their toes followed by those possessed the lesions on the plantar (140/320, 43.7%). The lesion stages of IV and V were observed in 49.1% (157/320) of visited patients which were more common in rural regions (86%) than in urban areas (14%). For treatment, removing the fleas using needle (122/320, 38.1%), followed by the application of petroleum (100/320, 31.2%) were among the most traditional remedies used by our patients.

CONCLUSION

This investigation highlights a high burden of tungiasis in studied endemic foci in particular in rural regions. These results can be helpful in control management strategies against this parasitosis in Madagascar.

Current status of the knowledge on the epidemiology of tungiasis in the Americas

Objectives.

To present the state-of-the-knowledge on the epidemiology of tungiasis in the Region of the Americas.

Methods.

A search of publications on the epidemiology of tungiasis in the Americas was performed in PubMed and LILACS databases from January 2007 to June 2021. In addition, a manual literature search on articles on the epidemiology of tungiasis was performed.

Results.

A total of 83 articles were analyzed which contained relevant information on tungiasis cases and their geographical distribution, prevalence and risk factors, life cycle, sites where transmission takes place, and zoonotic aspects. The on-host and off-host life cycles have been researched in detail. In certain contexts, the whole life cycle is completed indoors enabling transmission around the whole year. Cases were reported from 10 countries; 71% of them were from Brazil. In the general population, the prevalence varied between 1.0% and 82.6% according to the settings. Age-specific prevalence indicated that children and the elderly bear the highest disease burden. Risk factor studies indicate that tungiasis is associated with severe poverty.

Conclusions.

In the Americas, there are important gaps in information and knowledge of tungiasis. Understanding the burden, epidemiology, distribution, magnitude, related risk factors, and reservoirs, among others, is needed to develop and implement integrated control measures tailored to the context and patterns of transmission in the affected communities.

Environmental and Household-Based Spatial Risks for Tungiasis in an Endemic Area of Coastal Kenya

Tungiasis is a cutaneous parasitosis caused by an embedded female sand flea. The distribution of cases can be spatially heterogeneous even in areas with similar risk profiles. This study assesses household and remotely sensed environmental factors that contribute to the geographic distribution of tungiasis cases in a rural area along the Southern Kenyan Coast. Data on household tungiasis case status, demographic and socioeconomic information, and geographic locations were recorded during regular survey activities of the Health and Demographic Surveillance System, mainly during 2011. Data were joined with other spatial data sources using latitude/longitude coordinates. Generalized additive models were used to predict and visualize spatial risks for tungiasis. The household-level prevalence of tungiasis was 3.4% (272/7925). There was a 1.1% (461/41,135) prevalence of infection among all participants. A significant spatial variability was observed in the unadjusted model (p-value < 0.001). The number of children per household, earthen floor, organic roof, elevation, aluminum content in the soil, and distance to the nearest animal reserve attenuated the odds ratios and partially explained the spatial variation of tungiasis. Spatial heterogeneity in tungiasis risk remained even after a factor adjustment. This suggests that there are possible unmeasured factors associated with the complex ecology of sand fleas that may contribute to the disease's uneven distribution.

Evaluating the potentials of randomised integrated control trial on tungiasis in a South-western Nigerian community

Considering the fact that new, safe and incorporable treatment alternatives to therapeutic prophylaxis for tungiasis are lacking and sometimes proving difficult, this present study evaluated the potentials of integrating control approach involving focal premise treatment using 5% emulsifiable concentrate of cypermethrin, and topical application of Piper guineense oil with personal protection. Of the 90 houses selected, their floors were classified into paved rooms & unpaved verandas, paved verandas & unpaved rooms, paved rooms & verandas, and unpaved rooms & verandas, and tested for the presence of sand fleas using the sweeping and beating as well as soil collection and extraction by tullgren funnel method before fumigation. A total of 100 individuals partitioned into four groups of 25 individuals each were assigned 3%, 5%, 10% and 15% of P. guineense oil irrespective of stages of embedded fleas. The mean of sand fleas decreased from 1.14, 0.07, 0.21, and 1.66 to 0.37, 0.02, 0.09 and 1.08 after two weeks of single spray compared to the untreated location (p <  0.001). Furthermore, the mean lesions of stage I reduced to 0 after 2 to 6 days of 3%, 5%, 10% and 15% ointment application, and stage II and III after 10 to 12 days of 10% and 15% application respectively. The difference between tungiasis stages and exposure time for P. guineense ointment was highly significant p = 0.007 and p = 0.0002. Notable reduction in severity score of acute and chronic tungiasis was observed thus indicating effectiveness of the topical ointment. Hexanolic oil extracts of P. guineense in 10% and 15% concentration would kill embedded sand flea and ameliorate the sufferings in endemic settings.

Therapeutic Potential of Tea Tree Oil for Tungiasis

Tungiasis (sand flea disease) is a neglected tropical disease caused by penetration of female sand fleas, Tunga penetrans, into a person's skin usually in their feet. The disease inflicts immense pain and suffering on millions of people, particularly children. The condition is most prevalent in Latin America, the Caribbean, and sub-Saharan Africa. Currently, there is no standard drug treatment for tungiasis. The available treatment options are fairly limited and unrealistic to use in endemic areas; as a result, in desperation, the affected people do more harm to themselves by extracting the fleas with non-sterile instruments, further exposing themselves to secondary bacterial infections and/or transmission of diseases such as hepatitis B virus, hepatitis C virus, or HIV. This highlights the urgent need for simpler, safer, and effective treatment options for tungiasis. Tea tree oil (TTO) has long been used as an antiseptic with extensive safety and efficacy data. The evidence on parasiticidal properties of TTO against ectoparasites such as head lice, mites, and fleas is also compelling. The purpose of this review is to discuss the current tungiasis treatment challenges in endemic settings and highlight the potential role of TTO in the treatment of tungiasis.

Assessment of the role played by domestic animals in jigger infection in Kandara sub-county, Kenya (case control study)

Introduction

tungiasis is an ectoparasitosis caused by penetration of female sand flea, Tunga penetrans, into the skin of the susceptible animal and the consequent hypertrophy of the parasite. The objective of this study was to assess the association between domestic animals and jigger infection among the residents of Kandara sub-county in central Kenya.

Methods

this was a case-control study that involved 776 individuals. Half of this number entailed case group who were jigger infected while the other half was the control, composed of jigger free participants. Structured questionnaires were, administered among the heads of the households to which the participants belonged to gather information concerning the animals they kept. Univariate analysis was, applied.

Results

in this study, there were significant differences in age (P=0.008) between the two groups. Disparities in source of income (P<0.001) and level of education (P<0.001) came out as very significant factors in jigger infection. The case group was 10 times more likely to keep dogs than the control(9.6; 95% CI, 5.9-15.6). Case group was also 7 times more likely to rear chicken in comparison to the control (6.6; 95%, 4.2-10.4). The case group was 12 times more likely to let dogs loose in the compound in comparison to the control (12.1: 95%, 5.9-24.5). When compared to the control, this group was also 17 times more likely to keep chicken inside their houses (16.7: 95% CI, 6.8-35.9). Conclusion: there is a very high association between domestic animals and occurrence of tungiasis in Kandara sub-county.

Treatment of tungiasis using a tea tree oil-based gel formulation: protocol for a randomised controlled proof-of-principle trial

INTRODUCTION

Tungiasis (sand flea disease or jigger infestation) is a neglected tropical disease caused by penetration of female sand fleas, Tunga penetrans, in the skin. The disease inflicts immense pain and suffering on millions of people, particularly children, in Latin America, the Caribbean and sub-Saharan Africa. Currently, there is no standard treatment for tungiasis, and a simple, safe and effective tungiasis treatment option is required. Tea tree oil (TTO) has long been used as a parasiticidal agent against ectoparasites such as headlice, mites and fleas with proven safety and efficacy data. However, current data are insufficient to warrant a recommendation for its use in tungiasis. This trial aims to generate these data by comparing the safety and efficacy of a 5% (v/w) TTO proprietary gel formulation with 0.05% (w/v) potassium permanganate (KMnO₄) solution for tungiasis treatment.

METHODS AND ANALYSIS

This trial is a randomised controlled trial (RCT) in primary schools (n=8) in South-Western Kenya. The study will include school children (n=88) aged 6-15 years with a confirmed diagnosis of tungiasis. The participants will be randomised in a 1:1 ratio to receive a 3-day two times a day treatment of either 5% TTO gel or 0.05% KMnO₄ solution. Two viable embedded sandflea lesions per participant will be targeted and the viability of these lesions will be followed throughout the study using a digital handheld microscope. The primary outcome is the proportion of observed viable embedded sand fleas that have lost viability (non-viable lesions) by day 10 (9 days after first treatment). Secondary outcomes include improvement in acute tungiasis morbidities assessed using a validated severity score for tungiasis, safety assessed through adverse events and product acceptability assessed by interviewing the participants to rate the treatment in terms of effectiveness, side effects, convenience, suitability and overall satisfaction.

ETHICS AND DISSEMINATION

The trial protocol has been reviewed and approved by the University of Canberra Human Research Ethics Committee (HREC-2019-2114). The findings of the study will be presented at scientific conferences and published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBERS

Australian New Zealand Clinical Trials Registry (ACTRN12619001610123); PACTR202003651095100 and U1111-1243-2294.

Human Ectoparasites Are Highly Prevalent in the Rural Communities of Northwest Ethiopia: A Community-Based Cross-Sectional Study

BACKGROUND

Ectoparasites are organisms which inhabit the skin or outgrowths of the skin of another organism (the host). Many ectoparasites are known to be vectors of pathogens, which the parasites typically transmit to hosts. Though, ectoparasites are common in the vulnerable groups and economically disadvantaged communities, there is limited evidence on its magnitude in Ethiopia. This community-based cross-sectional study was, therefore, conducted to assess the prevalence and associated factors of ectoparasites in the rural communities of northwest Ethiopia.

METHODS

A community-based cross-sectional study design with structured observation was conducted among 1191 randomly selected rural households in northwest Ethiopia in May 2016. Data were collected using structured interviewer administered interview questionnaire and structured observation checklist. Prevalence of human ectoparasites in the rural communities was defined as the presence of one or more lice, fleas, bed bugs, mites, and ticks and the presence of these ectoparasites were observed by trained environmental health experts. Multivariable binary logistic regression analysis was used to identify variables associated with prevalence of ectoparasites on the basis of adjusted odds ratio (AOR) with 95% confidence interval (CI) and P values <.05.

RESULTS

Of a total of 1191 rural households, human or hair lice were observed in one or more of the family members in 186 (15.6%) rural households. Similarly, fleas were observed in more than half, 609 (51.1%) of rural households and bed bugs were observed in 441 (37%) rural households. Furthermore, mites and ticks were reported in 113 (9.5%) and 130 (10.9%) of the households respectively. Accordingly, one or more ectoparasites were observed in 865 of 1191 rural households. The presence of one or more ectoparasites was, therefore, found to be 72.6% (95% CI = 70%-75.1%). The prevalence of ectoparasites was statistically associated with educational status of the female head being not educated (AOR = 1.476, 95% CI = 1.001, 2.177) and absence close supervision by health extension workers (AOR = 2.151, 95% CI = 1.205, 3.843).

CONCLUSION

The prevalence of one or more ectoparasites was high in the rural communities of northwest Ethiopia. The high prevalence was associated with education status of the female head and close supervision of households by health extension workers. Disseminating health information about intervention strategies of ectoparasites and closely supervising the rural households need to be considered.

Clinical interventions for tungiasis (sand flea disease): a systematic review

Tungiasis (sand flea disease) is an epidermal parasitic skin disease occurring in resource-limited communities. There is no standard treatment for tungiasis, and available treatment options are scarce. To our knowledge, this is the first systematic review aimed to assess randomised controlled trials (RCTs) investigating interventions for tungiasis. We systematically searched databases including MEDLINE (EBSCOhost), CENTRAL, CINAHL, PubMed, Web of Science, SciELO, LILACS and Embase (Scopus) for RCTs in any language, from inception of the databases until June 12, 2021. RCTs exploring preventive and therapeutic interventions for tungiasis were eligible. We used the revised Cochrane Collaboration's risk of bias tool to assess the risk of bias and Jadad scale to quantify the methodological quality of the RCTs. Of the 1839 identified records, only eight RCTs involving 808 participants were included, and several methodological deficiencies were identified in most of the trials. Trial interventions included: oral drugs niridazole and ivermectin and topical interventions of ivermectin lotion, metrifonate lotion, thiabendazole lotion, thiabendazole ointment, dimeticones (NYDA), and a neem seed and coconut oils-based mixture for treatment and coconut oil-based lotion (Zanzarin) for prevention. The coconut oil-based lotion for prevention and dimeticones for treatment of tungiasis have displayed the most promise. Most of the RCTs included in this study had low methodological quality. There is a clear unmet need for high-quality RCTs examining safe and effective prevention and treatment alternatives of tungiasis in endemic settings.

Tungiasis in the urban area of Popayán, Colombia: A case report

La tungiasis es una ectoparasitosis endémica en Latinoamérica y está asociada a factores de riesgo como la ruralidad, la pobreza y la convivencia con animales. Popayán, una ciudad al suroccidente de Colombia, fue históricamente afectada por la tungiasis, tanto así que a sus habitantes los apodan "patojos" debido a la forma de caminar de sus habitantes infestados por la pulga. Hoy la enfermedad se creía eliminada. Se presenta el caso de un niño de 12 años procedente del área urbana de Popayán, que consultó por lesiones papulares de bordes circulares, centro negruzco y halo hiperqueratósico en ambos pies, de un mes de evolución. Por los hallazgos clínicos se sospechó tungiasis y se le administró ivermectina. Las lesiones se removieron quirúrgicamente y se enviaron para análisis parasitológico, el cual confirmó la presencia de Tunga penetrans. La evolución del paciente fue satisfactoria. La Secretaría de Salud Municipal de Popayán inspeccionó el domicilio del paciente y encontró perros migrantes del Pacífico colombiano en sus alrededores, algunos con lesiones sospechosas de tungiasis. Se documenta, así, el resurgimiento de esta enfermedad en el área urbana, probablemente debido a la migración de animales desde las zonas rurales. Es importante reconocer la existencia de la pulga en zonas rurales y urbanas, hacer el diagnóstico médico y reportar los casos a los entes de vigilancia. Estas acciones permitirán ofrecer un apropiado manejo y control sanitario de esta ectoparasitosis desatendida en humanos y animales.

Intensity and clinical morbidities of tungiasis in an impoverished south-west Nigerian community

Sand fleas infestation, Tunga penetrans, remains a neglected tropical disease of public-health concern in many countries. Tungiasis can lead to destruction of the feet causing serious discomfort and deformities. This study aim was to determine the intensity rate and clinical morbidities of tungiasis among the people living in Igbokoda, Ondo State, Nigeria. A community-based cross-sectional survey was conducted among households in three villages in Igbokoda. Hands and feet of selected household members were examined, while fleas on different floor types of houses were sampled by soil collection and extraction by tullgren funnel method. Sand fleas were equally sampled from legs of infested individuals by hand picking. Intensity was determined in terms of number of lesions and fleas in different floor-types. Tungiasis-associated morbidities was assessed using acute and chronic lesions severity scores. The study revealed that moderate infestation was observed in 173 infested individuals and severe infestation in 16 infested individuals. A total of 5293 lesions was observed out of which 3098 were viable. The flea burdens on sampled floors and legs were 127 and 146 fleas respectively occurring mostly in unpaved veranda and rooms (65 and 62 fleas respectively). Tungiasis lesions observed in males were more intense compared to females. Flea lesions and burdens with respect to age stratification and location were significant P < 0.0001. Difficulty in walking, pain upon pressure and deformation of the feet were the most common tungiasis-associated morbidity recorded. Also, tungiasis-associated morbidities, and flea number sampled on legs and on floor of environment were reportedly intense. Therefore, scaling up an appropriate and affordable intervention approach targeted at the fleas would serve as a relief to the scourge of tungiasis in Igbokoda community.

Clinical implications and treatment options of tungiasis in domestic animals

Tunga penetrans, Tunga trimamillata and Tunga hexalobulata are the three species of sand fleas which cause tungiasis in domestic animals. Tunga penetrans and T. trimamillata are zoonotic in the tropical and sub-tropical endemic communities of Latin America and Africa. Tungiasis in animals frequently occurs alongside human tungiasis. Currently, most of the attention given to tungiasis is focusing on the human disease, and animal tungiasis is extremely neglected despite its public health and animal health significance. This review highlights recent findings concerning the clinical implications and treatment options but also summarises the occurrence, major features, public health and economic significance of tungiasis in domestic animals. Pigs, dogs, cats and domestic ruminants have been reported to harbour high intensities of sand fleas in endemic communities. High infection intensities cause significant animal morbidity which is often exacerbated by excoriations and secondary bacterial infections which are potentially fatal. In addition to the potential economic losses accruing from tungiasis-related morbidity, infected domestic animals contribute to transmission and persistence of sand fleas and eventually also to severe human disease. Although control of animal tungiasis is possible by adoption of proper husbandry practices, affected communities may not afford the resources required to implement them. Also, there are no widely acceptable and affordable insecticides for treatment of tungiasis in animals. Extension services aiming at increasing awareness on tungiasis and its control should be intensified. Also, available commercial insecticides should be evaluated for therapeutic and prophylactic properties against animal tungiasis.

Epidemiology of tungiasis in sub-saharan Africa: a systematic review and meta-analysis

Tungiasis is a public health disease in many rural and urban slums in sub-Saharan Africa (SSA), primarily affecting children and the elderly. Yet, this disease has received little attention in many sub-Saharan African countries. We conducted a systematic review and meta-analysis to estimate the pooled prevalence of tungiasis and associated risk factors in SSA. We searched AJOL, Google Scholar, Web of Science, and PubMed for population-based studies that reported the prevalence of tungiasis and risk factors in SSA between January 1980 and July 2020. The study employed a random-effects model and heterogeneity to estimate the pooled prevalence and evaluate the Cochran's Q-test respectively across studies that met the inclusion criteria. We screened 104 articles and retrieved 42 full-text articles to evaluate for inclusion in the review. Twenty-seven studies involving 16,303 individuals in seven SSA countries were analyzed. The pooled prevalence of tungiasis in SSA was 33.4% (95% CI: 27.6-39.8), while tungiasis prevalence was 46.5%, 44.9%, 42.0%, 37.2%, 28.1%, 22.7% and 20.1% for Ethiopia, Cameroon, Tanzania, Kenya, Nigeria, Rwanda, and Uganda, respectively. The risk of tungiasis was associated with gender, participants' age groups (4-15 years and ≥60 years), earthen floor, non-regular use of footwear, contact with animals, and residence in rural areas. An integrated approach addressing significant factors in tungiasis prevalence in SSA needs to be designed and implemented by a trans-disciplinary composition of community leaders, health professionals, non-governmental institutions, and policymakers.

Factors associated with tungiasis among primary school children: a cross-sectional study in a rural district in Rwanda

BACKGROUND

Tungiasis is a relatively frequent ectoparasitosis in low-income settings, yet its morbidity and social impact are still not well understood due to the scarcity of information. In Rwanda, data on the magnitude and conditions leading to the tungiasis is rare. This study sought to determine the prevalence and factors associated with tungiasis among primary school children in Rwandan setting.

METHOD

A descriptive cross-sectional study utilising systematic random sampling method was adopted to select 384 children from three primary schools. From July to October 2018, data were collected on socio-demographic characteristics of children, parents, and households. Logistic regression was applied to analyse socio-demographic factors associated with tungiasis with a level of significance set at P-value< 0.05.

RESULTS

Prevalence of tungiasis among three primary schools was 23%. Factors associated with tungiasis included walking barefoot (AOR: 78.41; 95% CI: 17.91-343.10), irregular wearing of shoes (AOR: 24.73; 95% CI: 6.27-97.41), having dirty feet (AOR: 12.69; 95% CI: 4.93-32.64), wearing dirty clothes (AOR: 12.69; 95% CI: 4.18-38.50), and living in a house with earthen plastered floor (AOR: 28.79; 95% CI: 7.11-116.57). Children infected with tungiasis attended class less frequently (AOR: 19.16, 95%CI: 7.20-50.97) and scored lower (AOR: 110.85, 95%CI: 43.08-285.20) than those non-infected. The low school attendance and poor performance could be partly explained by difficulty of walking, lack of concentration during school activities, and isolation or discrimination from classmates.

CONCLUSION

Tungiasis was a public health challenge among school going children in a rural Rwandan setting. This study revealed that children affected with tungiasis had poor hygiene, inadequate housing environments and consequently poor school attendance and performance. Improving socio-economic conditions of households with special emphasis on hygiene of family members and housing conditions, would contribute to preventing tungiasis.

Prevalence, intensity and risk factors of tungiasis in Kilifi County, Kenya II: Results from a school-based observational study

Introduction

Awareness of the public health importance of tungiasis has been growing in East Africa in recent years, but data on epidemiological characteristics necessary for the planning and implementation of control measures do not exist. The work presented here was part of a larger cross-sectional study on the epidemiology of tungiasis in coastal Kenya and aims at identifying risk factors of tungiasis and severe disease in school children.

Methods

A total of 1,829 students of all age groups from five schools and 56 classes were clinically examined for tungiasis on their feet based on standardized procedures and observations made about the school infrastructure. To investigate the impact of school holidays, observations were repeated after school holidays in a subset of children in one school. In an embedded case-control study, structured interviews were conducted with 707 students in the five schools to investigate associations between tungiasis and household infrastructure, behaviour and socio-economic status.

Results

The overall prevalence of tungiasis was 48%; children below the age of 15 years were the most affected, and boys were twice as likely as girls to be infected. The highest risk of disease was associated with the socio-economic circumstances of the individual student at home. The study indicated that mild to moderate tungiasis could be reduced by a third, and severe tungiasis by over half, if sleeping places of children had hardened floors, whilst approximately a seventh of the cases could be prevented by sealing classroom floors in schools, and another fifth by using soap for daily feet washing.

Conclusion

There is a clear role for public health workers to expand the WASH policy to include washing of feet with soap in school-aged children to fight tungiasis and to raise awareness of the importance of sealed floors.

Tungiasis is a neglected tropical skin disease caused by penetrated sand fleas, the adult female of which burrows into the skin of the feet. The parasite rapidly expands its body size by a factor of 2000. The growth causes immense itching, inflammation, pain and debilitation. The current lack of good treatment methods means people attempt to remove the fleas themselves with non-sterile instruments causing more damage. Control efforts focus on prevention but there is little data to guide this in East Africa. The current study reinforces our previously published results on the household level from the same communities, indicating that prevention needs to focus on hardening the floors of resource-poor families and integrating daily foot washing with soap into water, hygiene and sanitation programs.

Very severe tungiasis in Amerindians in the Amazon lowland of Colombia: A case series

Background

Tungiasis is a parasitic skin disease caused by penetrating female sand fleas. By nature, tungiasis is a self-limiting infection. However, in endemic settings re-infection is the rule and parasite load gradually accumulates over time. Intensity of infection and degree of morbidity are closely related.

Methodology/principal findings

This case series describes the medical history, the clinical pathology, the socio-economic and the environmental characteristics of very severe tungiasis in five patients living in traditional Amerindian communities in the Amazon lowland of Colombia. Patients had between 400 and 1,300 penetrated sand fleas. The feet were predominantly affected, but clusters of embedded sand fleas also occurred at the ankles, the knees, the elbows, the hands, the fingers and around the anus. The patients were partially or totally immobile. Patients 1 and 3 were cachectic, patient 2 presented severe malnutrition. Patient 3 needed a blood transfusion due to severe anemia. All patients showed a characteristic pattern of pre-existing medical conditions and culture-dependent behavior facilitating continuous re-infection. In all cases intradomiciliary transmission was very likely.

Conclusion/significance

Although completely ignored in the literature, very severe tungiasis occurs in settings where patients do not have access to health care and are stricken in a web of pre-existing illness, poverty and neglect. If not treated, very severe tungiasis may end in a fatal disease course.

Tungiasis (also called sand flea disease) is a neglected tropical disease (NTD) caused by the penetration of female sand fleas in the skin, typically at the toes, the sole or the heel. Once embedded in the upper strata of the skin, the parasite hypertrophies, enlarging its body size by a factor of 2000 within ten days. This causes intense inflammation with pain and itching, eventually leading to impaired mobility. During a period of three weeks, eggs are expelled through a tiny opening in the skin. When the last egg has been released into the environment, the parasite shrinks and eventually dies. Hence, by nature tungiasis is a self-limited infection. However, in endemic settings re-infection is the rule and parasite load gradually accumulates over time. Here we report five cases with extremely severe tungiasis in patients with 400 to 1,300 embedded sand fleas. Not only the feet were affected, but clusters of parasites also occurred at the ankles, the knees, the elbows, the hand, the fingers and around the anus. The patients were partially or totally immobile. Two patients were cachectic and one required a blood transfusion. All patients showed a characteristic pattern of pre-existing medical conditions and culture-related behaviour facilitating continuous re-infection.

Tungiasis-related life quality impairment in children living in rural Kenya

BACKGROUND

Tungiasis (sand flea disease) is a neglected tropical skin disease caused by female sand fleas (Tunga spp.) embedded in the skin of the host. The disease is common in sub-Saharan Africa and predominantly affects children living in impoverished rural communities. In these settings tungiasis is associated with important morbidity. Whether tungiasis impairs life quality has never been studied.

METHODS

The study was performed in 50 children with tungiasis, living in resource-poor communities in coastal Kenya. Based on the Dermatology Life Quality Index (DLQI) a tool was developed to determine life quality impairment associated with tungiasis in children, the tungiasis-related Dermatology of Life Quality Index (tungiasis-related-DLQI). Pain and itching were assessed using visual scales ranging from 0-3 points. The intensity of infection and the acute and chronic severity of tungiasis were determined using standard methods.

RESULTS

Seventy eight percent of the patients reported a moderate to very large effect of tungiasis on life quality at the time of the diagnosis. The degree of impairment correlated with the number of viable sand fleas present in the skin (rho = 0.64, p < 0.001), the severity score of acute clinical pathology (rho = 0.74, p < 0.001), and the intensity of pain (rho = 0.82, p < 0.001). Disturbance of sleep and concentration difficulties were the most frequent restriction categories (86% and 84%, respectively). Four weeks after curative treatment, life quality had improved significantly. On the individual level the amelioration of life quality correlated closely with the regression of clinical pathology (rho = 0.61, p < 0.001).

CONCLUSION

The parasitic skin disease tungiasis considerably impairs life quality in children in rural Kenya. After effective treatment, life quality improves rapidly.

Tungiasis. A Case of Diagnosis of Tropical Dermatosis

A case of tungiasis is presented — infestation with Tunga penetrans of a man who was on vacation in Peru, with eruptions localized on toes I and V of the both feet. For treatment of the patient, the parasites were surgically removed out of the lesions, whereupon the lesions were treated with antiseptics.

Prevalence, intensity and risk factors of tungiasis in Kilifi County, Kenya: I. Results from a community-based study

BACKGROUND

Tungiasis is a neglected tropical disease caused by female sand fleas (Tunga penetrans) embedded in the skin. The disease is associated with important morbidity. Tungiasis is endemic along the Coast of Kenya with a prevalence ranging from 11% to 50% in school-age children. Hitherto, studies on epidemiological characteristics of tungiasis in Africa are scanty.

METHODS

In a cross-sectional study 1,086 individuals from 233 households in eight villages located in Kakuyuni and Malanga Sub-locations, Kilifi County, on the Kenyan Coast, were investigated. Study participants were examined systematically and the presence and severity of tungiasis were determined using standard methods. Demographic, socio-economic, environmental and behavioral risk factors of tungiasis were assessed using a structured questionnaire. Data were analyzed using bivariate and multivariate regression analysis.

RESULTS

The overall prevalence of tungiasis was 25.0% (95% CI 22.4-27.5%). Age-specific prevalence followed an S-shaped curve, peaking in the under-15 year old group. In 42.5% of the households at least one individual had tungiasis. 15.1% of patients were severely infected (≥ 30 lesions). In the bivariate analysis no specific animal species was identified as a risk factor for tungiasis. Multivariate analysis showed that the occurrence of tungiasis was related to living in a house with poor construction characteristics, such as mud walls (OR 3.35; 95% CI 1.71-6.58), sleeping directly on the floor (OR 1.68; 95% CI 1.03-2.74), the number of people per sleeping room (OR = 1.77; 95% CI 1.07-2.93) and washing the body without soap (OR = 7.36; 95% CI 3.08-17.62). The odds of having severe tungiasis were high in males (OR 2.29; 95% CI 1.18-44.6) and were very high when only mud puddles were available as a water source and lack of water permitted washing only once a day (OR 25.48 (95% CI 3.50-185.67) and OR 2.23 (95% CI 1.11-4.51), respectively).

CONCLUSIONS

The results of this study show that in rural Kenya characteristics of poverty determine the occurrence and the severity of tungiasis. Intra-domiciliary transmission seems to occur regularly.

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

BACKGROUND

Tungiasis (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.

METHODS

In 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.

RESULTS

Independent 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).

CONCLUSIONS

Our findings suggest that the dimeticone could provide a safe and effective treatment for tungiasis in areas with difficult access to health care.

TRIAL REGISTRATION

ISRCTN ISRCTN74306878.

Successful Treatment of Severe Tungiasis in Pigs Using a Topical Aerosol Containing Chlorfenvinphos, Dichlorphos and Gentian Violet

Background

In endemic communities, zoonotic tungiasis, a severe skin disease caused by penetrating female sand fleas, is a public health hazard causing significant human and animal morbidity. No validated drugs are currently available for treatment of animal tungiasis. Due to the reservoir in domestic animals, integrated management of human and animal tungiasis is required to avert its negative effects.

Methods and principal findings

A topical aerosol containing chlorfenvinphos 4.8%, dichlorphos 0.75% and gentian violet 0.145% licensed to treat tick infestations, myiasis and wound sepsis in animals in the study area, was tested for its potential tungicidal effects in a randomized controlled field trial against pig tungiasis in rural Uganda. Animals with at least one embedded flea were randomized in a treatment (n = 29) and a control (n = 26) group. One week after treatment, 58.6% of the treated pigs did not show any viable flea lesion whereas all control pigs had at least one viable lesion. After treatment the number of viable lesions (treated median = 0, overall range = 0–18 vs. control median = 11.5, range = 1–180) and the severity score for estimating acute pathology in pig tungiasis (treated median = 1, range = 0–3.5 vs. control median = 7, range = 0–25) were significantly lower in treated than in control pigs (p < 0.001). In the treatment group the median number of viable flea lesions decreased from 8.5 to 0 (p < 0.001). Similarly, the median acute severity score dropped from 6 to 1 (p < 0.001). Every pig in the treatment group showed a decrease in the number of viable fleas and tungiasis-associated acute morbidity while medians for both increased in the control group.

Conclusions

The study demonstrates that a topical treatment based on chlorfenvinphos, dichlorphos and gentian violet is highly effective against pig tungiasis. Due to its simplicity, the new approach can be used for the treatment of individual animals as well as in mass campaigns.

Infection with the sand flea Tunga penetrans causes severe disease in humans and animals. There are no validated drugs for treatment of animal tungiasis preventing implementation of integrated tungiasis control interventions targeting human and animal infections. A field trial was conducted to evaluate the effects of a commercial insecticidal aerosol containing chlorfenvinphos 4.8%, dichlorphos 0.75%, and gentian violet 0.145%, which is licensed to treat tick infestations, myiasis and wound sepsis, on tungiasis in pigs, the major animal reservoir in rural hyperendemic villages in Uganda. Infected pigs were recruited and randomly assigned to treatment (n = 29) and control (n = 26) groups. Seven days after a single application of the aerosol onto the affected body parts, almost 60% of the treated pigs were cured while all control pigs had at least one penetrated sand flea. The number of viable sand fleas and the severity of the tungiasis were significantly lower in the treated pigs than in the controls. This demonstrates for the first time that a simple and effective topical treatment for animal tungiasis based on two organophosphate insecticides and an antibacterial agent can be used to cure individual animals and can be integrated in tungiasis control campaigns.

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.

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

BACKGROUND

Tunga 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.

METHODS

This 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.

RESULTS

The 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).

CONCLUSIONS

The 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.

Epidemiology of tunga penetrans infestation in selected areas in Kiharu constituency, Murang'a County, Kenya

BACKGROUND

Tungiasis is a parasitic skin disease brought about by female Tunga penetrans when they burrow into the skin of their hosts. It is a disease that has largely been ignored. Epidemiology of tungiasis has not been widely studied in Kenya which could negatively affect effective intervention strategies. This study therefore sought to investigate epidemiology of tungiasis in selected areas in Kiharu constituency, Murang'a County in Kenya.

METHODS

The study population comprised of public primary school pupils, the most vulnerable age group (n = 508) in Gaturi, Kimathi, Kahuhia and Mugoiri in Kiharu constituency. Public primary school pupils in the study area were randomly sampled. Through questionnaires and observations, data was collected.

RESULTS

The overall prevalence of tungiasis in pupils in the study area was 19.1 %. In multinomial logistic regression analysis some factors were identified to be associated with tungiasis such as lack of regular use of closed foot ware (Adjusted odds ratio = 10.45; 95 % Confidence Interval; 1.49-73.23), living in earthen mud walled houses (aOR = 13.78; 95 % CI = 3.127-60.69), sharing living quarters with domestic animals (aOR = 3.1; 95 % CI = 0.003-.046) and learning in classrooms with dusty floors (aOR = 14.657; 95 % CI = 2.262-94.95). Treatment of tungiasis was found to be mainly through mechanical removal of embedded T. penetrans.

CONCLUSION

This study shows that tungiasis in the selected study areas of Kiharu constituency is a disease of significant health concern. Factors associated with tungiasis were identified that should be the focus of sustainable and effective control measures.

Characterization of Tunga penetrans antigens in selected epidemic areas in Murang'a county in Kenya

Tunga penetrans are fleas that cause tungiasis, a condition characterized by high transmission rate due to poor housing conditions, social neglect and inadequate health care in economically disadvantaged communities in developing countries. This study therefore aimed at characterizing jiggers antigens to identify immunodominant ones to help understand immunological behavior of the parasite that would otherwise be important in future control of the parasite. Samples were gravid fleas and blood samples from infested individuals in Kahuro and Murang'a East district in Murang'a County. Freeze and thaw was used to extract soluble proteins from the fleas. Ouchterlony Double immunodiffusion was used to assess antigen-antibody reactions between extracted soluble protein and the serum from immunized rats, Rattus norvegicus prior to analysis of human sera. These results were comparable to results of immunoelectrphoresis. Jigger protein isolates were analyzed in Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis technique (SDS-PAGE), against Pharmacia standard protein markers. Further analysis of jigger antigens against pooled human sera from infested victims in Western blot revealed three immunodominant antigens. Using simple regression analysis molecular weights of the three immunodominant antigens were estimated as 51.795, 23.395 and 15.38 kDa respectively. These results are important since they would help understand immunological behavior of the parasites. This would help to create basis for designing and improving approaches against jiggers such as development of immune prophylaxis to complement social science approaches that is mainly concerned with maintenance of high standards of hygiene.

Health and safety issues for travelers attending the World Cup and Summer Olympic and Paralympic Games in Brazil, 2014 to 2016

IMPORTANCE

Travelers from around the globe will attend the 2014 Fédération Internationale de Football Association (FIFA) World Cup and the 2016 Olympic and Paralympic Games in Brazil. Travelers to these mass gathering events may be exposed to a range of health risks, including a variety of infectious diseases. Most travelers who become ill will present to their primary care physicians, and thus it is important that clinicians are aware of the risks their patients encountered.

OBJECTIVE

To highlight health and safety concerns for people traveling to these events in Brazil so that health care practitioners can better prepare travelers before they travel and more effectively diagnose and treat travelers after they return.

EVIDENCE REVIEW

We reviewed both peer-reviewed and gray literature to identify health outcomes associated with travel to Brazil and mass gatherings. Thirteen specific infectious diseases are described in terms of signs, symptoms, and treatment. Relevant safety and security concerns are also discussed.

FINDINGS

Travelers to Brazil for mass gathering events face unique health risks associated with their travel.

CONCLUSIONS AND RELEVANCE

Travelers should consult a health care practitioner 4 to 6 weeks before travel to Brazil and seek up-to-date information regarding their specific itineraries. For the most up-to-date information, health care practitioners can visit the Centers for Disease Control and Prevention (CDC) Travelers' Health website (http://wwwnc.cdc.gov/travel) or review CDC's Yellow Book online (http://wwwnc.cdc.gov/travel/page/yellowbook-home-2014).

Tungiasis in Haiti: a case series of 383 patients

BACKGROUND

Tungiasis is endemic in poverty-stricken communities of South and Central America, Africa, Asia, and the Caribbean. This ectoparasitosis, caused by the female sand flea Tunga penetrans, is associated with considerable longterm morbidity in severely affected patients, including toe deformation and limited mobility. In Haiti, tungiasis is poorly documented but is known to occur. This study is the first formal investigation of tungiasis in Haiti.

METHODS

A total of 383 patients in four regions (Belle Fontaine, Vallue, Savanette, Cerca Carvajal) were examined and interviewed to determine disease prevalence, demographics and clinical presentation, and tungiasis-related behaviors.

RESULTS

Prevalences of tungiasis ranged from 10.6 to 81.8% across the four regions. The overall prevalence of tungiasis in the patients examined was 31.1%. Of the affected patients, 63% were male and 37% were female, 37% were aged 0-10 years, and 100% reported pain and pruritus. Lesions occurred on the feet in 93.3% and on the hands in 22.7% of affected patients. The most common complications observed were chronic inflammation (54.2%) and hyperkeratosis (48.2%).

CONCLUSIONS

This study establishes tungiasis as endemic in four regions of Haiti and reveals disease characteristics similar to those reported previously, suggesting that there are common factors underlying this disease in various regions, which are likely to be poverty-related. These findings emphasize the need to acknowledge tungiasis as a clinically relevant public health issue in order to decrease the frequency of tungiasis-related morbidity in endemic areas.

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.

Tungiasis - A Janus-faced parasitic skin disease

Tungiasis is a parasitic skin disease caused by the penetration of female sand fleas (Tunga penetrans). It is acquired when people walk barefoot or rest on soil, where sand fleas have completed the off-host cycle. Tungiasis is a classic poverty-associated disease which belongs to the family of neglected tropical diseases (NTD). It has a Janus-face: while in travellers tungiasis usually is a benign self-limiting skin disease, inhabitants of endemic areas suffer from heavy infestations and severe, frequently debilitating and incapacitating morbidity. We describe the epidemiological and clinical characteristics of travel-associated tungiasis and compare these features to the situation in resource-poor communities in South America and sub-Saharan Africa.

Prevention of tungiasis and tungiasis-associated morbidity using the plant-based repellent Zanzarin: a randomized, controlled field study in rural Madagascar

Background

Tungiasis, a parasitic skin disease caused by the female sand flea Tunga penetrans, is a prevalent condition in impoverished communities in the tropics. In this setting, the ectoparasitosis is associated with important morbidity. It causes disfigurement and mutilation of the feet. Feasible and effective treatment is not available. So far prevention is the only means to control tungiasis-associated morbidity.

Methodology

In two villages in Central Madagascar, we assessed the efficacy of the availability of closed shoes and the twice-daily application of a plant-based repellent active against sand fleas (Zanzarin) in comparison to a control group without intervention. The study population was randomized into three groups: shoe group, repellent group and control group and monitored for ten weeks. The intensity of infestation, the attack rate and the severity of tungiasis-associated morbidity were assessed every two weeks.

Findings

In the repellent group, the median attack rate became zero already after two weeks. The intensity of the infestation decreased constantly during the observation period and tungiasis-associated morbidity was lowered to an insignificant level. In the shoe group, only a marginal decrease in the intensity of infestation and in the attack rate was observed. At week 10, the intensity of infestation, the attack rate and the severity score for acute tungiasis remained significantly higher in the shoe group than in the repellent group. Per protocol analysis showed that the protective effect of shoes was closely related to the regularity with which shoes were worn.

Conclusions

Although shoes were requested by the villagers and wearing shoes was encouraged by the investigators at the beginning of the study, the availability of shoes only marginally influenced the attack rate of female sand fleas. The twice-daily application of a plant-based repellent active against sand fleas reduced the attack to zero and lowered tungiasis-associated morbidity to an insignificant level.

Tungiasis (sand flea disease) is a parasitic skin disease present in many resource-poor communities in South America, the Caribbean and sub-Saharan Africa. In this setting tungiasis is associated with important morbidity. Hitherto, the only effective treatment is the surgical extraction of embedded sand fleas. In the endemic areas this is done using inappropriate sharp instruments and causes more harm than good. The prevention of the infestation is the only option to control morbidity. In this study we show that the twice daily application of a herbal repellent based on coconut-oil (Zanzarin), is highly effective in preventing sand flea disease in a heavily affected community in Madagascar. The attack rate became zero immediately after starting the application of the repellent. The degree of tungiasis associated morbidity approached zero within 10 weeks. In contrast, the availability of closed solid shoes had only a marginal protective effect; although shoes were requested by the villagers and wearing shoes was encouraged by the investigators at the beginning of the study. In a control group from the same village the attack rate, the intensity of infestation and of tungiasis-associated morbidity remained unchanged. Our study in rural Madagascar shows that effective und sustainable morbidity control is possible using a repellent derived from coconut oil.

Regression of severe tungiasis-associated morbidity after prevention of re-infestation: a case series from rural Madagascar

Tungiasis (sand flea disease) is a neglected tropical disease. Heavy infestation results in mutilation of the feet and difficulty in walking. We identified eight individuals with extremely severe tungiasis in rural Madagascar. To prevent reinfestation, four individuals received solid shoes and four received a daily application of an herbal repellent effective against Tunga penetrans. Over a period of 10 weeks the feet were examined and the severity of tungiasis-associated morbidity was measured. Within this period, the severity score for acute tungiasis decreased 41% in the shoe group and 89% in the repellent group. The four major inflammation-related symptoms disappeared in the four patients of the repellent group, but only in two patients of the shoe group. Those observations indicate that cases with extremely severe tungiasis, associated morbidity almost totally disappears within 10 weeks if the feet are protected by a repellent. Wearing shoes reduced acute morbidity only marginally.

Topographic distribution of the sand flea Tunga penetrans in Wistar rats and humans in two endemic areas in Brazil

Tungiasis is a zoonosis caused by Tunga penetrans. In Brazil, tungiasis is endemic in many resource-poor communities, in which various domestic and sylvatic animals act as reservoirs. Eighty laboratory-raised Wistar rats were exposed to T. penetrans in areas of intense transmission: a fishing village and an urban shantytown in Ceará State, northeast Brazil. The topographic distribution of lesions in Wistar rats was compared with the distribution of lesions in humans in the same area. Our results show that the topographic distribution of embedded sand fleas was almost identical in Wistar rats and humans and that lesions were confined to the feet. In humans, 76% of all lesions were located periungually, whereas in Wistar rats, 67% of lesions were located at the distal end of the digits (P = 0.73). Both had the majority of lesions at the toes and digits: 70.2% versus 65.7% (P = 0.79). The Wistar rat model mirrors human tungiasis in topographic distribution.

Tungiasis (sand flea disease): a parasitic disease with particular challenges for public health

Tungiasis (sand flea disease) is caused by the penetration of females of Tunga penetrans into the skin of the feet. Within 2 weeks of penetration the burrowed flea increases its volume by a factor of 2,000. This is paralleled by intense inflammation of the surrounding tissue. Acute and chronic inflammation leads to the development of painful and debilitating clinical pathology. This results in impaired physical fitness and mobility. The social implications of tungiasis-associated morbidity are multifold. Children with tungiasis are teased and ridiculed, adults feel ashamed and stigmatized. There is anecdotal evidence that tungiasis negatively affects educational achievements. Impaired mobility and physical fitness will have a negative impact on household economics. Sand flea disease is common in resource-poor communities in South America and in sub-Saharan Africa with prevalence in the general population of up to 60%. In East Africa, it has re-emerged in epidemic dimensions in recent years. Hitherto, no effective drug treatment has been at hand. Traditional treatment, i.e., the manipulation of burrowed sand fleas with blunt and inappropriate instruments may facilitate the transmission of blood-derived pathogens. Prevention is feasible through regular application of a repellent based on coconut oil. Owing to its strong association with poverty, sand flea disease would be an excellent starting point for a community-based fight against rural poverty.

Jigger flea infestation (tungiasis) in rural western Tanzania: high prevalence and severe morbidity

Epidemiologic and clinical data on the parasitic skin disease tungiasis are limited from sub-Saharan Africa, and virtually nonexistent from the East African region. We performed a community-based cross-sectional study in two villages in Kasulu district, western Tanzania. Study participants were examined for the presence of tungiasis and disease-associated morbidity. In total, 586 individuals >5 years of age were enrolled, and 249 (42.5%; 95% CI: 38.5-46.5) diagnosed with tungiasis. The ≥45 year-olds showed highest prevalence of tungiasis (71.1%) and most severe parasite load (median number of embedded fleas: 17.5; interquartile range: 15-22.5). Prevalence was slightly, but not significantly, higher in males than in females (45.3 vs 39.7%; p=0.17). Itching (68.3%), pain (38.6%) and ulcers (30.1%) were common; 22.1% of individuals found it difficult to walk due to tungiasis, and in 21.3% loss of toenails was observed. Considering the high prevalence and considerable morbidity in the population, we conclude that tungiasis is a public health threat in the study villages and that the disease needs to be recognized by health authorities. Future studies on risk factors, animal reservoirs and evidence-based control measures are needed.

Occurrence of the off-host life stages of Tunga penetrans (Siphonaptera) in various environments in Brazil

To explore the local transmission dynamics of Tunga penetrans in brazil, 134 soil samples from various environments were collected in three different endemic regions of the country and checked for the presence of the flea's larvae, pupae and adults. the samples, which came from an urban slum in the north-east, a village of xavante indians in the central-west and a community of yanomami indians living in traditional longhouses (malocas) in the north, were categorized as indoor, outdoor or indoor-outdoor (the latter representing samples collected in the malocas). The proportion of samples found positive for T. penetrans was lowest in the slum (9.3%) and highest in the Yanomami village (32.0%; P=0.01). Soil samples collected below bedsteads or hammocks or from the indoor resting places of dogs were significantly more likely to be positive than the indoor samples collected at other sites (65.0% v. 35.0%; P=0.02). There was no evidence indicating that the presence of T. penetrans in a soil sample was markedly affected by soil temperature, air temperature or air humidity. As no life stages of T. penetrans were found in any outdoor sample, it seems likely that, in resource-poor settings in Brazil, most transmission of T. penetrans occurs indoors. Control measures against the off-host life stages of T. penetrans should therefore be targeted at particular indoor micro-environments.

Control of tungiasis through intermittent application of a plant-based repellent: an intervention study in a resource-poor community in Brazil

BACKGROUND

Tungiasis, an ectoparasitosis caused by the female sand flea Tunga penetrans, is an important health problem in many impoverished communities in the tropics. Sand flea disease is associated with a broad spectrum of clinical pathology and severe sequels are frequent. Treatment options are limited.

METHODOLOGY/PRINCIPAL FINDINGS

We assessed the effectiveness of the intermittent application of the plant-based repellent Zanzarin to reduce infestation intensity and tungiasis-associated morbidity in a resource-poor community in Brazil, characterized by a very high attack rate. The study population was randomized into three cohorts. Initially, during a period of four weeks, the repellent was applied twice daily to the feet of all cohort members. This reduced the number of embedded sandfleas to 0 in 98% of the participants. Thereafter members of cohort A applied the repellent every second week twice daily for one week, members of cohort B every fourth week for one week, and members of cohort C served as controls. Infestation intensity and tungiasis-associated morbidity were monitored during five months. The intermittent application of Zanzarin for one week every second week significantly reduced infestation intensity from a median 4 lesions (IQR 1-9) during the whole transmission season. In contrast, in cohort B (application of the repellent every fourth week) the infestation intensity remained twice as high (median 8 lesions, IQR 9-16; p = 0.0035), and in the control cohort C 3.5 times as high (median 14 lesions; IQR 7-26; p = 0.004 during the transmission season). Tungiasis-related acute pathology remained very low in cohort A (median severity score 2; IQR 1-4) as compared to cohort B (median severity score 5; IQR 3-7; p<0.001), and control cohort C (median severity score 6.5; IQR 4-8; p<0.001).

CONCLUSIONS/SIGNIFICANCE

Our study shows that in a setting with intense transmission, tungiasis-associated morbidity can be minimized through the intermittent application of a plant-based repellent.

A simple method for rapid community assessment of tungiasis

OBJECTIVE

To evaluate a rapid assessment method to estimate the overall prevalence of tungiasis and severity of disease in endemic communities.

METHODS

We analysed data from 10 population-based surveys on tungiasis, performed in five endemic communities in Brazil and Nigeria between 2001 and 2008. To assess the association between occurrence of tungiasis on six defined topographic areas of the feet and the true prevalence/prevalence of severe disease, linear regression analyses were performed. Estimated prevalences were calculated for each of the 10 surveys and compared to true prevalences. We then selected the most useful topographic localization to define a rapid assessment method, based on the strength of association and operational aspects.

RESULTS

In total, 7121 individuals of the five communities were examined. Prevalence of tungiasis varied between 21.1% and 54.4%. The presence of periungual lesions on the toes was identified as the most useful rapid assessment to estimate the prevalence of tungiasis (absolute errors: -4% to +3.6%; R(2 )=96%; P < 0.0001). Prevalence of severe tungiasis (>20 lesions) was also estimated by the method (absolute errors: -3.1% to +2.5%; R(2 )=76%; P = 0.001).

CONCLUSION

Prevalence of tungiasis and prevalence of severe disease can be reliably estimated in communities with distinct cultural and geographical characteristics, by applying a simple and rapid epidemiological method. This approach will help to detect high-risk communities and to monitor control measures aimed at the reduction of tungiasis.