Identifying risk factors for tungiasis and heavy infestation in a resource-poor community in northeast Brazil

Abstract

Tungiasis is a neglected parasitic skin disease caused by penetration of female sand fleas into the epidermis. The ectoparasitosis is widespread in resource-poor communities in South America, the Caribbean and sub-Saharan Africa. To identify risk factors for the presence of sand fleas and severe infestation in an endemic community, we examined the entire population of a traditional fishing village for the presence of embedded sand fleas and determined the number and type of lesions. Demographic, behavioural and environmental characteristics of the population were assessed using a structured questionnaire. Multivariable analysis showed that both occurrence of tungiasis and heavy infestation were significantly related to poor housing conditions (odds ratio [OR]=4.7, 95% CI 1.4-15.8), lack of health education (OR=4.1, 95% CI 2.0-8.6) and presence of animals on the compound (OR=1.9, 95% CI 1.1-3.4). Contrary to common belief, a protective effect of frequent use of closed footwear could not be demonstrated. Based on the population attributable fractions calculated for the major risk factors identified, we conclude that several low-cost interventions would have a considerable impact on the occurrence of tungiasis and heavy infestation.

Tungiasis infestation in Tanzania

“…The report indicates that, similar to recent accounts from other African countries such as Nigeria [2,16], Madagascar [17] and Cameroon [18,19], the disease may also reach high parasite loads in individuals in Tanzania, with consequently severe pathology, in contrast to milder cases reported by returning tourists. The patient was living under conditions previously described as risk factors in studies from Brazil and Nigeria [20,21]: i.e., people living under poor conditions, usually in houses with floors made of sand or mud. The type of soil in the area is red clay soil which gives much dust during the dry season.…”

Assessment of Socioeconomic status and the Prevalence of Tungiasis in Jimma and Wolaita sodo, Ethiopia

“…People occasionally visiting other areas were excluded. The selected individual's clinical evaluation was conducted to reveal the severity of the infection [10].…”

“…Tunga penetrans complete its life cycle in the sandy or muddy floor of the houses and it premises. So poor houses with muddy or sandy soil, unhygienic health behavior of the population, all these factors affects the rate of infection [10][11][12]. Previous studies revealed that there were high prevalence of disease in sheep, dog and pig [8,13,14].…”

Conhecimento dos profissionais de saúde sobre a situação da tungíase em uma área endêmica no município de Uberlândia, Minas Gerais, Brasil, 2010

“…Vários estudos também corroboram que crianças são mais susceptíveis à tungíase, devido, principalmente, a seu comportamento em áreas pobres onde ocorre a doença, como andar descalço ou brincar em contato direto com o solo. 9,12,25,26 Alguns autores também acreditam que a prevalência da tungíase tem relação com a idade: a queratinização da pele dos pés dos adultos dificultaria a penetração da pulga. 27,28 Em relação ao sexo, os estudos disponíveis são discordantes.…”

“…Em áreas endêmicas, as altas infestações estão associadas, principalmente, a condições precárias de moradia, falta de educação em saúde e presença de animais. 25 As infecções secundárias são muito comuns na tungíase, causadas por uma grande variedade de microorganismos patogênicos. 13,31,33,34 Entre as formas de prevenção, as mais conhecidas dos profissionais foram o uso de calçados e as práticas de higiene.…”