Protecting our Health from Climate Change: a Training Course for Public Health Professionals

1. Protecting our Health from Climate Change: a Training Course for Public Health Professionals Water Stress:Chapter 11: Water and Foodborne Diseases

2. Overview: Water Stress and Water and Foodborne Disease Water quantity and quality Burden of diarrheal disease How climate and weather affects diarrheal diseases and food and waterborne pathogens Season Temperature Precipitation (flooding and drought) Sea level rise Summary

3. Water Quantity and Quality Issues IPCC, 2007a

4. Water Quantity and Quality Issues (cont.)

5. Burden of Waterborne Disease 1.8 million deaths (4 million cases) in 2004 due to gastroenteritis (WHO) 88% due to unsafe water and poor sanitation Prüss-Üstün et al., 2008

6. Burden of Waterborne Disease (cont.) Prüss-Üstün et al., 2008

7. Distribution of Fatal Drownings World Health Organization, 2008c

8. Burden of Diarrheal Diseases Diarrheal diseases are vastly underestimated 211 million cases estimated in the US annually (Mead et al., 1999) Reported cases Actual cases > 38 x reported cases

9. Climate Change and Waterborne Disease Climate change scenarios include Rising temperature Changes in hydrologic cycle Increased drought Increased storm intensity Change in frequency of “extreme events” Hurricanes Ocean-atmosphere oscillations ENSO NAO Others Sea level rise Can affect a wide range of enteric pathogens, especially those with an environmental reservoir

10. Direction and Magnitude of Climate Change Health Impacts IPCC AR4, 2007

11. Climate Already Affects Waterborne Disease Hall et al., 2002

12. How Do Climate and Weather Affect Enteric Pathogens?

13. Diarrheal Disease Pathways Prüss-Üstün et al., 2008

14. How Climate Can Influence Water and Foodborne Disease Trends Local temperature Replication in the environment or associated with food products Persistence Local rainfall Loading into the environment (contamination) Increased concentration of contaminants (drought)

15. How Climate Can Influence Water and Foodborne Disease Trends (cont.) Sea level rise Influx of marine pathogens Flooding (storm surge), contamination, loss of infrastructure Range expansion among zoonotic agents and their hosts

16. Seasonal Trends in Rotavirus Infections Cook et al., 1990

17. Local Temperature

18. Climate Driver: Temperate Effects IPCC, 2007a

19. Impact of Climate Variation and Change on Diarrheal Disease Singh et al., 2001

20. Salmonellosis Kovats et al., 2004

21. Salmonella Trends Hall et al., 2002

22. Campylobacteriosis Kovats et al., 2005

23. Vibrio spp. Vibrio are commonly estuarine and marine bacteria and include at least 12 known pathogens to humans V. vulnificus V. parahaemolyticus V. cholerae In general, this group replicates easily in natural waters and biota, especially under high temperatures Directly related to increasing water temperatures

24. Cholera in South America

25. Vibrio parahaemolyticus OutbreakAlaska – 2004 McLaughlin et al., 2005

26. Local Rainfall Run-off Flooding Drought

27. Vulnerability of Freshwater Resources IPCC, 2007a

28. Climate Change Impacts on Runoff IPCC, 2007a

29. Very Wet Days: Importance to Total Precipitation and Changes over Time Bates et al., 2008

30. Flooding Risk factors Direct contact with contaminated water Skin Respiratory Ear and eye infections Ingestion of contaminated water (wells, etc.) Gastroenteritis Insufficient water treatment (i.e., problem at the tap) Additional secondary spread

31. Extreme Precipitation and Waterborne Disease Outbreaks Curriero et al., 2001

32. Walkerton Rainfall Auld et al., 2004

33. Example: Walkerton Outbreak Worthington et al., 2002

34. Cryptosporidiosisand Precipitation C. hominis Other Crypto spp. Das et al., 2006

35. Rainfall, Run-off, and Pathogen Contamination Building evidence for the association between diarrheal disease and increased precipitation, especially with heavy rainfall events In addition, several studies note increased pathogen loads related to floods, run-off, and heavy precipitation including: Enteric viruses (e.g., enteroviruses, noroviruses, adenoviruses) Protozoan parasites (e.g., Cryptosporidium, Giardia, others) Enteric bacteria (e.g., Salmonella, Campylobacter, E. coli, fecal indicator bacteria)

36. Drought Effects on Water Quality CRCWQT, 2005

37. Sea Level Rise

38. Cities Vulnerable to Sea Level Rise Heavily populated Delta regions that are vulnerable to sea level rise World Health Organization, 1996, Figure 7.3

39. Cholera: South Asia Yearly epidemics correspond to natural environmental cycles and contamination Influx of estuarine water Plankton blooms Monsoons Warm temperatures Cycles can be modeled for year to year changes in outbreaks

40. Bay of Bengal: Sea Surface Height Lobitz et al., 2000

41. Bay of Bengal: Sea Surface Temperature Lobitz et al., 2000

42. Bay of Bengal: Cholera and Sea Surface Height Lobitz et al., 2000

43. Waterborne Disease Climate projections for increased warming and increased extreme events suggest waterborne diseases may increase Mitigation and adaptation will be enhanced by understanding the ecology of pathogens What underlying factors provide the link to climate? How do changing landscapes affect disease incidence under changing climate conditions?

44. Public Measures to Address Potential Issues Associated with Climate Change The effects of climate change on water and foodborne diseases can be mitigated Focus on public health response Focus on basic infrastructure Increased attention to treatment options We have tools to address problems and prevent disease, understanding how climate may increase risk can be used to prioritize adaptation or rapid response measures