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 DiseasesDivision 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

Filtered Water

(aka “filtrate” or “permeate”)

UF Membrane

• Microbes• Suspended solids• Colloidal matter• Large dissolved molecules

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)

Membrane filtration (bacteria)

Nucleic Acid

Extraction

Toxin TestingVirus Testing (e.g., qPCR)

Culture

Boil Prep-qPCR

Direct Nucleic

Acid Extraction

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

National Center for Emerging and Zoonotic Infectious DiseasesDivision of Foodborne, Waterborne and Environmental Diseases

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"