The Domestic Public Health Impact of Climate Change: U.S. Perspective on Waterborne Disease Transmission

Michael J. Beach, Ph. D.Centers for Disease Control

and Prevention

Potential U.S. Health Effects of Climate Change

Climate change:

• Temperature rise• Sea level rise• Hydrologic

extremes

HEAT Heat stress, cardiovascular failure

SEVERE WEATHER Injuries, fatalities

AIR POLLUTION Asthma, cardiovascular disease

ALLERGIES Respiratory allergies, poison ivy

VECTOR-BORNE DISEASES Malaria, dengue, encephalitis, hantavirus, Rift Valley fever

WATER-BORNE DISEASES Cryptosporidiosis, Naegleria, Campylobacteriosis, vibriosis leptospirosis

WATER AND FOOD SUPPLY Malnutrition, diarrhea, algal blooms, hygiene-related disease

MENTAL HEALTH Anxiety, post-traumatic stress, despair, depression

ENVIRONMENTAL REFUGEES Forced migration, civil conflict

Adapted from J. Patz

Potential Climate Change-related Events Impacting Waterborne Disease

• Environmental change/disturbance• Extreme weather events

• Flood: CSO, SSOs•Drought: soil/geologic changes

• Re-use of water and wastewater• Urbanization

• Increased cooling system usage•Exploitation of man-made habitats

• Legionella, Mycobacterium

Potential Climate Change-related Events Impacting Waterborne Disease

• Increasing water temperatures and/or nutrients• Enhanced growth of pathogens• Naegleria, Vibrio, Pseudomonas, HAB

• HAB-Related Illness Surveillance System (HABISS)• Environmental data, animal and human

illness • All recreational water indicators Increasing

recreational activities• Swimming pools, ambient waters

How Can Changes in Waterborne Disease Transmission Be Monitored?

Waterborne-Disease Surveillance:Real World

• Not all water-related pathogens and chemicals are nationally notifiable

• Most water-related pathogens and chemicals have multiple modes of transmission

• Most individual cases are not investigated so mode of transmission is unknown

• Reported cases represent only a small portion of the burden of disease

• Water quality databases have no connection to health effects data

Are There Surrogates for Waterborne Disease Case

Reporting?

• Outbreaks can serve as indicators for trends in waterborne disease transmission in the U.S. and can connect health effects with water quality data

0

10

20

30

40

50

60

1971 1974 1977 1980 1983 1986 1989 1992 1995 1998 2001* 2004

Year

Num

ber o

f WB

DO

S_

National Waterborne Disease and Outbreak Surveillance System

• Collaborative surveillance system• CDC, EPA, CSTE since 1971

• State/local DOH’s have 10 responsibility for detecting, investigating, reporting WBDOs

Waterborne Disease and Outbreak Surveillance System: Usefulness

• Disease control• Identify contaminated water sources

• Knowledge of disease causation• Identify etiologic agents (old and new)

• Trend identification• Etiologic agents, water sources, deficiencies

• Guidance and evaluation• Evaluate the adequacy of current technologies

for providing safe water• Establish research priorities• Assess effectiveness of water regulations/codes

Drinking Water-Associated Outbreaks, United States, 1971-2004

0

10

20

30

40

50

60

1971 1974 1977 1980 1983 1986 1989 1992 1995 1998 2001* 2004

Year

Num

ber o

f WB

DO

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N=803, MMWR (2006) 55(SS12):31-65

•Beginning in 2003, mixed agents of more than 1 etiologic agent type were included in the surveillance system. However, the first observation is a previously unreported outbreak in 2002.

•† Beginning in 2001, Legionnaires’ disease was added to the surveillance system, and Legionellaspecies were classified separately in this figure.

Public, surface water Private, groundwater

Opportunities for Improvement:Needed ASTHO Assistance

• Support CSTE in making WBDO’s nationally notifiable in your state

• Support deployment of National Outbreak Reporting System (NORS) from CDC• Expanded version of Foodborne Outbreak Reporting

System (eFORS)• Put an emphasis on improved detection,

investigation, and reporting of WBDOs• Training• Improved risk factor data collection

Acknowledgements

DPD• Michael Beach• Sharon Roy• Jonathan Yoder• Michele Hlavsa

EPA• Rebecca Calderon• Gunther Craun

Newly Required Disclaimer From the Department of Health

and Human Services

• "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“