Tungíase: doença negligenciada causando patologia grave

Tropical Medicine and International Health volume 15 no 7 pp 856–864 july 2010
L. Ariza et al. Rapid community assessment of tungiasis
developed for a variety parasitic diseases and health
conditions, mainly in low-income countries (Anker 1991;
Vlassoff & Tanner 1992; Macintyre 1999; Macintyre et al.
1999). For example, the macroscopic presence of haematuria
(Lengeler et al. 1991, 2002a,b; Red Urine Study
Group 1995), the identification of palpable nodules in the
skin (Ngoumou et al. 1994; Whitworth & Gemade 1999;
Kipp & Bamhuhiiga 2002) and the presence of elephantiasis
and hydrocele (Gyapong et al. 1996, 1998a,b;
Weerasooriya et al. 2008) have been used to estimate the
prevalence of urinary schistosomiasis, onchocerciasis and
lymphatic filariasis, respectively. Rapid assessment methods
are commonly used to plan and monitor mass
interventions, but also to detect parasitized individuals.
Control of tungiasis at the community level has rarely been
attempted (Heukelbach et al. 2001; Pilger et al. 2008), and
rapid assessments methods are not available.
Because in endemic areas 95–98% of sand flea lesions
are restricted to the feet (Heukelbach et al. 2002, 2007a;
Ugbomoiko et al. 2007), we assessed different topographic
areas of the feet to be used as a rapid method for the
presence of sand fleas. An area was identified that would
give a reliable proxy to estimate prevalence of tungiasis.
The occurrence of tungiasis on periungual sites of the toes
was the most reliable and practical approach to estimate
overall prevalence and severity of disease.
Materials and methods
Study areas
We included data from 10 cross-sectional populationbased
surveys conducted in five communities between 2001
and 2008. Three communities are located in Northeast
Figure 1 Location of study areas (a) in
Brazil (Ceará and Alagoas State) and (b)
Nigeria (Lagos State).
Brazil, two in Southwest Nigeria. The communities studied
in Brazil were Balbino, a fishing village in Ceará State
(Northeast Brazil); Morro do Sandras, an urban slum in
the city of Fortaleza (capital of Ceará State); and Feliz
Deserto, a rural community in Alagoas State. In Nigeria,
data were collected in Yovoyan and Okunilaje, two small
fishing villages in Lagos State (Southwest Nigeria,
Figure 1).
All five communities were characterized by low socioeconomic
status, but showed distinct cultural and geographical
characteristics. The study areas had in common
that streets were not paved, and families were extremely
poor (mean monthly family income equivalent to € 45.00).
Illiteracy rates ranged between 15% and 30%. Whereas in
Brazil, more than 90% of households had electric power
supply, no access to electricity existed in the Nigerian
communities. In Nigeria, the vast majority of houses were
built of palm stems; and in Brazil, most houses were made
of bricks or adobe. The main characteristics of the
communities and their populations are depicted in Table 1.
As tungiasis is known to show a particular seasonal
variation (Heukelbach et al. 2005), data were collected in
different periods of the year (dry and rainy season). In
Nigeria, surveys were conducted during dry season only, as
in the rainy season isolated communities are not accessible.
In addition, according to key informants, tungiasis virtually
does not occur in these communities during the heavy
rain falls typical of this region in Nigeria.
Detailed prevalence data on the Brazilian communities
have been published previously (Wilcke et al. 2002;
Muehlen et al. 2003; Heukelbach et al. 2005, 2007a).
Clinical examinations were performed by investigators
trained in an endemic area in Brazil and monitored by
the same team leader. Field investigators were monitored
Ceara
Alagoas
Lagos
(a) (b)
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