Direct One-step Culture Detection of Vibrio cholera in Drinking Water in Low-Resource and Disaster Settings

EPA Grant Number: SU836116
Title: Direct One-step Culture Detection of Vibrio cholera in Drinking Water in Low-Resource and Disaster Settings
Investigators: Sobsey, Mark D.
Institution: University of North Carolina at Chapel Hill
EPA Project Officer: Sergeant, Anne
Phase: I
Project Period: September 1, 2015 through August 31, 2016
Project Amount: $14,569
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2015) RFA Text |  Recipients Lists
Research Category: P3 Awards , Pollution Prevention/Sustainable Development , Sustainability , P3 Challenge Area - Water

Objective:

The objective is to develop and evaluate a new quantitative, culture-based test to detect and quantify Vibrio cholerae bacteria in drinking water and its sources by adapting the Compartment Bag Test for use with a new, defined substrate, chromogenic liquid culture medium that will be created, thereby resulting in a lab-independent, field-portable and self-contained test system.

Approach:

The goal and plan is to adapt the CBT system to the development of a V. cholerae CBT by modifying and evaluating its performance, based on sensitivity, selectivity and specificity. Three standard, chromogenic, V. cholerae selective agar media, Thiosulfate Citrate Bile Sucrose (TCBS) Agar, CHROMagar Vibrio, and Tellurite taurocholate Gelatin Agar (TTGA), will be modified to produce chromogenic, V. cholera-specific broth culture media. Media modifications include, eliminating agar and varying and optimizing candidate chromogens, fluorogens, and other supplements to enhance performance as broth culture media to detect V. cholerae in drinking waters. Each candidate medium will be tested under various water quality and environmental conditions of incubation temperature and water quality (pH, turbidity, organic matter, etc.) in order to model drinking water conditions in developing countries. The performance of the test will be adapted for ease of use to field water quality monitoring surveillance, with the goal of fostering community-based, participatory water quality monitoring for V. cholera. Empowering people and communities to test their water for cholera bacteria is expected to enhance cholera monitoring of water across sectors and foster future innovations in cholera surveillance.

Expected Results:

Develop, performance validate and field test an effective and field portable version the CBT to detect and quantify V. cholerae in drinking water in the developing world and disasters settings. The results include meeting the following design and performance criteria for developing the field test:

  1. Fully portable field test for chromogenic detection and quantification of V. cholerae in drinking water samples.
  2. Requires no electric power, other equipment, advanced training, or other analytical steps.
  3. Costs no more or less than current tests for fecal indicator or bacterial pathogens.
  4. Quantifies V. cholerae in broth culture in the range of 0-100 MPN/100mLwith accuracy.
  5. Achieve an effective test for monitoring to support surveillance of V. cholerae in drinking water.

Supplemental Keywords:

Vibrio cholerae, detection, drinking water, compartment bag test, chromogenic culture medium