V. Water as a Food Safety Program, “The Water We Eat”

Water quality is an essential component to food safety. Food production processes use water in many ways including irrigation, cleaning, cooling, and storing. While there are limited environmental data to support the etiological connection, water contamination has been suspected in recent foodborne disease outbreaks. Acquiring data to support the connection is challenging due to the following:

• Most contamination occurs long before field investigations are performed, which reduces the likelihood of detecting the causative agent or pathogen
• Time delays between the time of contamination and recognition that an outbreak is occurring
• Subsequent time needed to organize and plan environmental investigations
• Collecting samples in diverse and dynamic environments
• The capacity for testing is usually only available at the federal level

CDC’s Waterborne Disease Prevention Branch (WDPB) is working to address these challenges. WDPB’s core mission activities include providing outbreak response support for foodborne disease outbreaks in which water quality is a potential risk factor. These efforts include

• Providing guidance on how to conduct environmental investigations and assessment of water resources as part of root cause analyses
• Research on irrigation water quality, produce wash water systems, and water quality in processing facilities
• Improving field and laboratory investigation methods
• Building federal, state, and local capacity for environmental investigations
• Health promotion related to safe water, sanitation, and hygiene
• Contributing to science-based best practices and policies for agricultural water

WDPB Surveillance Activities

The U.S. burden of waterborne diseases is estimated at 7.2 million cases, which includes 600,000 emergency department visits, 120,000 hospital stays, and 7,000 deaths, and costs $3.2 billion (hospital stays and emergency department visits) annually. The top pathogens implicated in the cases are norovirus, giardiasis, and cryptosporidiosis. Ninety-four percent of the deaths and 78 percent of the costs are biofilm-associated (non-tuberculous mycobacteria infection, Legionnaire’s Disease, Pseudomonas pneumonia, and septicemia).

WDPB currently collects data about waterborne illness through the following systems:

• Waterborne Disease and Outbreak Surveillance System (WBDOSS)
  • Collects data on waterborne disease outbreaks associated with drinking water, recreational water, environmental, and undetermined exposures to water
• National Outbreak Reporting System (NORS)
  • Detects foodborne, waterborne, and enteric outbreaks due to person-to-person, animal contact, or unknown mode of transmission
• One Health Harmful Algal Bloom System (OHHABS)
  • Collects environmental event data and clinical information from human and animal cases of harmful algal bloom exposure
• CryptoNet
  • Collects data on cryptosporidiosis using molecular-based surveillance

Food-water Nexus Partnerships and Capacity Building & Looking Forward

Capacity can be improved by recognizing the overlap and synergies between programs:

• Local environmental health programs, local health departments, and water utility emergency preparedness
• State and federal food and water programs
  • CDC ELC funding to support combined food and water programs
• Infectious disease and environmental health programs
  • CSTE Infectious Disease and Environmental Health committees now jointly discussing food and water priorities

Discussion/Response

Discussion

The Working Group’s discussion included the following observations:

• Efforts are underway to determine attribution estimates of foodborne disease caused by contaminated water.
• Currently, there is little state or national capacity to conduct environmental investigations for water-related foodborne disease. No explicit field or lab training programs exist for waterborne disease; however, WDPB conducts ad hoc training in sample collection as part of outbreak responses.
• Federal collaboration (CDC, FDA, U.S. Environmental Protection Agency) is key. Quality assurance and standardization of methods should be included across agencies.

Response

Based on these questions, the Working Group highlighted the following possible responses: