Household spraying in cholera outbreaks: Insights from three exploratory, mixed-methods field effectiveness evaluations

PLoS Negl Trop Dis. 2020 Aug 31;14(8):e0008661. doi: 10.1371/journal.pntd.0008661. eCollection 2020 Aug.

Abstract

Household spraying is a commonly implemented, yet an under-researched, cholera response intervention where a response team sprays surfaces in cholera patients' houses with chlorine. We conducted mixed-methods evaluations of three household spraying programs in the Democratic Republic of Congo and Haiti, including 18 key informant interviews, 14 household surveys and observations, and 418 surface samples collected before spraying, 30 minutes and 24 hours after spraying. The surfaces consistently most contaminated with Vibrio cholerae were food preparation areas, near the patient's bed and the latrine. Effectiveness varied between programs, with statistically significant reductions in V. cholerae concentrations 30 minutes after spraying in two programs. Surface contamination after 24 hours was variable between households and programs. Program challenges included difficulty locating households, transportation and funding limitations, and reaching households quickly after case presentation (disinfection occurred 2-6 days after reported cholera onset). Program advantages included the concurrent deployment of hygiene promotion activities. Further research is indicated on perception, recontamination, cost-effectiveness, viable but nonculturable V. cholerae, and epidemiological coverage. We recommend that, if spraying is implemented, spraying agents should: disinfect surfaces systematically until wet using 0.2/2.0% chlorine solution, including kitchen spaces, patients' beds, and latrines; arrive at households quickly; and, concurrently deploy hygiene promotion activities.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chlorine
  • Cholera / epidemiology*
  • Cholera / prevention & control*
  • Congo / epidemiology
  • Disease Outbreaks / prevention & control
  • Disinfection / methods*
  • Family Characteristics*
  • Female
  • Haiti / epidemiology
  • Health Knowledge, Attitudes, Practice
  • Humans
  • Male
  • Surveys and Questionnaires
  • Toilet Facilities
  • Vibrio cholerae

Substances

  • Chlorine

Grants and funding

This work was funded by Research for Health in Humanitarian Crises (R2HC, grant awarded to DSL, Ref. 28374), by the Swiss National Science Foundation (fellowships awarded to KG, Ref. P1SKP2_174771 and P1SKP2_181335) and by the P.E.O. Foundation (scholarship awarded to KG, years 2016-2017). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.