Soil factors influencing the prevalence of tunga penetrans in Gaichanjiru location of Murang'a county, Kenya.
Abstract
The Tunga penetrans is an ectoparasite that embeds in the epidermis of its host and
results into a disease referred to as tungiasis. This study aimed at investigating soil
factors that influence off- host stages of Tpenetrans population and hence the
prevalence of tungiasis. This was cross sectional study where sixty households were
selected through simple random sampling technique from the area.
All individuals in the selected homesteads were examined for presence of tungiasis
related lesions. Tungiasis was manifested by presence of lesions of embedded T
penetrans at different stages of development. Soil samples collected from the
households were analyzed and examined for the presence of larval stages. Organic
matter content of the soil was determined through loss by ignition method in a muffle
furnace. Soil pH was determined using a pH standard probe meter. Soil moisture was
determined by drying the soil in an oven. Size of granules was determined using sieves
of specific sizes and an electromagnetic shaker machine. Color of the soil was
established using munsell soil colour chart. Soil samples were also examined for the
presence of larvae under a dissecting microscope.
Out of 374 persons living in the sampled houses, 48.5% of these persons were infested
with Tpenetrans. Of these 30% had severe infestations, 23% mildly infested and 47%
had low infestations. Data were analyzed using analysis of variance (ANOVA),
regression and Pearson correlation coefficients.
Soil factors influenced the prevalence of tungiasis by up to 33% (P=0.001) and the T
penetrans population by up to 39.7 % (P=O.OOO). Organic content had an insignificant relationship to tungiasis prevalence (P=O.179) and
population (P=O.615). Soil texture was also found to have no relationship with T
penetrans population (P=O.615) and prevalence of T penetrans (P=O.179). Soil colour
also had no influence on prevalence of T penetrans infestations (P=O.553) and
population T penetrans (P=O.660).
The soil pH influenced the population of T penetrans (P=O.OOO) but not the prevalence
of Tpenetrans infestations (P=O.532). The soil moisture also had an effect on
Tpenetrans population (P=O.OOO) and not on the prevalence of tungiasis (P=O.063).
Data from this study indicates that soil moisture and soil pH can be manipulated in order
to serve as targets of control of tungiasis in addition to other control measures. These
control measures would aim at interrupting the life cycle of T.penetrans by reducing
larva population and subsequently the adult population leading to low infestation and
hence reduced prevalence.
Citation
Master of Science in Applied Parasitology.Sponsorhip
University of NairobiPublisher
University of Nairobi School of Biological Sciences