Increasing the Capacity of US Public Health &
WLA Labs to Detect Biothreat Agents in
Drinking Water
Vincent Hill, Environmental Engineer
NCEZID, DFWED, Waterborne Disease Prevention Branch
Water Laboratory Alliance (WLA) Security Summit,
March 23, 2012
National Center for Emerging and Zoonotic Infectious Diseases
Division of Foodborne, Waterborne and Environmental Diseases
Background

US drinking water systems vulnerable to intentional
contamination
 Also source water, treatment, and distribution system deficiencies;
premise plumbing issues

Priority for public health: Emergency preparedness
 Ideally, use “universal” method to recover unknown biothreat
agent or multiple agents of concern

“Ultrafiltration” (UF) fits the bill
 Pore sizes rated on molecular scale (~1-10 nm)
 Can recover viruses, bacteria, parasites—even large toxins
 Commercially available, relatively inexpensive “dialyzers”
Hollow Fiber UF Schematic
Water Sample
•
•
•
•
Microbes
Suspended solids
Colloidal matter
Large dissolved molecules
UF Membrane
Filtered Water
(aka “filtrate” or “permeate”)
EPA & CDC Collaborating for Water-Related
Emergency Preparedness


Began collaborating ~2003 on UF methods
EPA’s focus: field-deployable instrument
 Automated UF device developed

CDC’s focus: lab-based method for Laboratory
Response Network (LRN)
 Lab-based UF method and associated secondary processing
protocol (“LRN Water Processing Protocol”) posted for LRN lab use
in 2007

EPA-CDC Study: No overall significant difference in
microbial recovery efficiency between the methods
(EPA 600/R-11/103, October 2011)
LRN Water Processing Protocol
10-100 L Drinking Water Sample
Ultrafiltration
Centrifugal Ultrafilter
(viruses, toxins)
Nucleic Acid
Extraction
Virus Testing
(e.g., qPCR)
Toxin Testing
Membrane filtration
(bacteria)
Culture
Direct
Nucleic Acid
Extraction
Boil PrepqPCR
qPCR
Tangential-flow Ultrafiltration
Centrifugal Ultrafiltration
Microfiltration
Proficiency Testing Project

Primary Goal: Increase number of LRN and WLA labs
identified by LRN as proficient to perform the protocol
 Secondary benefit: Increasing capacity to perform large-volume
water sample processing for waterborne pathogens

Enrolled 15 labs

Workshop and hands-on training at CDC (Atlanta)

Method practice at home lab

Proficiency Testing Study: April-May 2012
 Focus: biothreat agent recovery and detection
 Also: Use of new Quality Control parameter (E. faecalis recovery %)
Acknowledgements



EPA Collaborators
 Latisha Mapp
 Prisca Takundwa
 Erin Silvestri
LRN Colleagues
 Stephen Morse
 Beth Schweitzer
 Laura Jevitt
CDC Project Staff
 Chandra Schneeberger
 Jackie Knee
 Bonnie Mull
"The findings and conclusions in
this presentation have not been
formally disseminated by CDC
and should not be construed to
represent any agency
determination or policy"
National Center for Emerging and Zoonotic Infectious Diseases
Division of Foodborne, Waterborne and Environmental Diseases