Investigations on the biology, epidemiology, pathology and control of Tunga penetrans in Brazil

Abstract

Tungiasis is hyperendemic in many poor communities in Brazil and is associated with considerable morbidity. In order to understand the factors that determine the distribution of this ectoparasitosis in a rural community, an epidemiological study was carried out in a traditional fishing village in Ceará State, north-eastern Brazil. Based on active case detection and voluntary participation, 91% of the population (belonging to 95% of all families) was examined. Embedded fleas were looked for over all parts of the body, counted, and the lesions were staged. The overall prevalence of infestation was 51.3% (95% CI: 47.0-55.5). More males than females were infested (54.8% vs 48.3%); however, this difference was not statistically significant. Age-specific prevalence rates followed an S-shaped curve with peaks in children aged 5-9 years and people elder than 60 years. The parasite burden was high (range 1-145 lesions; arithmetic mean: 8.9) and particularly elevated in males, children <15 years and the elderly. The distribution of the parasite burden was uneven within the population with the majority of the lesions in a few individuals: the 23 subjects (8% of all infested) with severe infestation (>30 lesions) accounted for 1,366 of the 2,493 lesions (54.8%) documented. The study shows that tungiasis is a highly prevalent ectoparasitosis in this deprived community with a peculiar distribution of prevalence and parasite burden.

Tungiasis—A Neglected Disease with Many Challenges for Global Public Health

“…In a slum in Northeast Brazil, all 47 individuals returning to their households from a non-endemic area became infected within three weeks [47]. The age-specific prevalence shows a characteristic s-shaped pattern with a maximum prevalence in children between 5 and 14 years and elderly people [34]. Such an age-specific prevalence curve may indicate that there is no development of a protective immunity against penetrating sand fleas.…”

Investigations on the life cycle and morphology of Tunga penetrans in Brazil

“…This indicates a high incidence of free-living female fleas, which was confirmed by the permanently afflicted persons living in these rural suburbs (Heukelbach et al 2004;Feldmeier et al 2003;Muehlen et al 2003).…”

“…Tunga species (especially T. penetrans) have a wide host range including cats, dogs, pigs, donkeys, monkeys, and rodents (Heukelbach et al 2004). Two species parasitize humans namely, T. penetrans and the recently discovered species Tunga trimamillata (Hicks 1930;Eisele et al 2003;Muehlen et al 2003;Pampiglione et al 2002Pampiglione et al , 2003Pampiglione et al , 2004.…”

Upper Eyelid Localisation of <i>Tunga penetrans</i>

“…Travellers to endemic areas may import cases to other countries, including the United States and Europe [7, 8]. In the endemic areas, the prevalence ranges from 16 to 55% [9,10,11,12,13], but cases in other areas are sporadic. …”