A pilot study of dimeticone oils versus sodium carbonate treatment for tungiasis: A randomized cohort trial in Homa Bay County, Kenya

PLoS Negl Trop Dis. 2024 Jul 23;18(7):e0012341. doi: 10.1371/journal.pntd.0012341. eCollection 2024 Jul.

Abstract

Background: Tungiasis is a cutaneous parasitosis caused by the female flea Tunga penetrans. Two-component dimeticone (NYDA) is the only treatment for tungiasis recommended by the World Health Organization; however, this topical drug is not available in Kenya. In Western Kenya, sodium carbonate is commonly used in the treatment of tungiasis. This study evaluated the 7-day cure rates for tungiasis by comparing sodium carbonate and NYDA treatments in Homa Bay County, Kenya.

Methodology/principal findings: This was a randomized, observer-blinded, parallel-treatment cohort trial. Twenty-three eligible children with 126 flea infections were matched and randomized. All participants received both treatments, with one treatment on each foot. We recorded all health conditions/information, including inflammation scores and adverse events. Observations were performed on days 3, 5, and 7 using a digital microscope to confirm dead or live fleas based on the viability signs. Twenty-three children aged 3-13 years were analyzed. The proportion of dead fleas on day 7 was higher after NYDA treatment than after 5% sodium carbonate treatment (87% versus 64%, respectively, P = 0.01) NYDA. Median survival was 5 days for both treatments; NYDA had significantly higher trend of flea non-viability rate than 5% sodium carbonate (P<0.01). There were no significant differences in the inflammation score or pain/itchiness between the two treatments. On the last day, 14 children indicated their preference for NYDA in future treatment of tungiasis, whereas nine children preferred the 5% sodium carbonate solution.

Conclusions/significance: NYDA was significantly more effective than 5% sodium carbonate for tungiasis treatment. Both treatments were safe but the children preferred NYDA more. Future studies with more participants and an extended observation period are warranted to confirm our findings. The findings suggest that NYDA should be made more available in tungiasis endemic area.

Trial registration: UMIN-CTR; UMIN 000044320.

Publication types

  • Randomized Controlled Trial
  • Comparative Study

MeSH terms

  • Adolescent
  • Animals
  • Carbonates* / administration & dosage
  • Carbonates* / therapeutic use
  • Child
  • Child, Preschool
  • Cohort Studies
  • Dimethylpolysiloxanes
  • Female
  • Humans
  • Kenya / epidemiology
  • Male
  • Pilot Projects
  • Treatment Outcome
  • Tunga* / drug effects
  • Tungiasis* / drug therapy

Substances

  • Carbonates
  • sodium carbonate
  • dimethicone
  • Dimethylpolysiloxanes

Grants and funding

This work was supported by the Nagasaki University “Doctoral Program for World-leading Innovative and Smart Education” for Global Health, KENKYU SHIDO KEIHI and partially by the JSPS Grant-in-Aid for Scientific Research (KAKENHI) (Grant Number: JP19K10623) through a grant to YK. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.