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

PLoS Negl Trop Dis. 2017 Oct 9;11(10):e0005925. doi: 10.1371/journal.pntd.0005925. eCollection 2017 Oct.

Abstract

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.

MeSH terms

  • Adolescent
  • Adult
  • Animals
  • Child
  • Child, Preschool
  • Cross-Sectional Studies
  • Female
  • Humans
  • Infant
  • Kenya / epidemiology
  • Male
  • Middle Aged
  • Prevalence
  • Risk Factors
  • Tunga / physiology
  • Tungiasis / epidemiology*
  • Tungiasis / pathology*

Grants and funding

The study was supported by German Doctors e.V., Bonn, Germany. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.