Cryptosporidium parvum Norwalk Viruses: Anticipating, Recognizing, Evaluating, Controlling the Terrible Two.

1. Cryptosporidium parvum & Norwalk Viruses: Anticipating, Recognizing, Evaluating, & Controlling the Terrible Two. UC Berkeley CIDER Series David T. Dyjack, Dr.PH, CIH March 22, 2007

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3. Why are these organisms relevant to preparedness? Potential transmission exists in high density living environments Vulnerable populations at risk Partial resistance to traditional prevention measures Surveillance of flood-affected communities Waterborne disease transmission (e.g., enterotoxigenic Escherichia coli, Shigella, Salmonella, hepatitis A, Cryptosporidium & Noro virus agents) exists.

6. Norwalk viruses Family Caliciviridae Noroviruses Single Strand RNA >100 strains Small round ~180,000 annual cases Norwalk, Ohio - 1968

7. Clinical Presentation Nausea, vomiting, diarrhea, abdominal cramps Reversible damage to jejunum Loose/watery stools (blood & mucus absent) Abrupt onset/generally not severe Incubation:1-2 days Duration: 1-3 days (some cases longer) Infectious during acute phase & 1-2 days or longer after symptoms abate Antiviral contraindicated

8. Sampling Biological Stool - EM & RT PCR (acute phase) Serum - IgG/IgA (acute and convalescent) Environmental Molecular Diagnostics (emerging �for environmental samples such as food or H20)

9. Public Health Issues

10. Noro like virus outbreaks

11. Transmission Mode

12. Epidemiology Fecal-Oral Route Vomitus Extremely Hardy 1 Cruise Ship impacted on 12 successive voyages Nature of outbreaks suggests food and water

13. Prevention Vaccine currently unavailable Hygiene & sanitation essential Wash raw foods Avoid high risk foods Aggressive infection control measures (universal precautions) Exclude sick food handlers 48 hours after symptoms abate Exclude affected individuals from group activities for 48 after symptoms abate Launder soiled bedding with hot water and detergent

14. Case Study 1998 Tomales Bay, California 171 Cases � 44 clusters Oysters from approved shellfish area Source: failing septic system or boaters

15. Cryptosporidium Cryptosporidium parvum & C. hominis

18. What is Cryptosporidium? Protozoan Single Host Causes acute short-term infection Fecal-Oral, Water, & possibly respiratory secretions May become severe in children and immune compromised Increasingly recognized as a common cause of waterborne disease in U.S. Found in surface and recreational waters throughout U.S. First reported case 1976 By 2000 over 3000 cases reported

19. Clinical Presentation Watery diarrhea/Stomach cramps Fever/General malaise Vomiting/Weight loss Incubation Period 2-10 days (ave =7) Symptoms up to 2 weeks (cyclical) Treatment: Nitazoxanide (contraindicated for immune compromised) Possibly infectious for several weeks (non-treated hosts)

20. Biological Basis for Disease Ingestion Excystation occurs Sporozoites released Parasitize GI tract epithelial cells Asexual followed by sexual reproduction Infective thick wall oocysts excreted Cysts possibly viable for months in external environment

21. Cryptosporidium in Environment 5,000 oocysts per liter in raw sewage 1,000 oocysts per liter in treated wastewater Two to 112 oocysts per liter in several western U.S. rivers

22. Cryptosporidiosis

23. Who is at risk? Child care workers Children who attend daycare centers Parents Swimmers (recreational waters) Outdoor enthusiasts Municipal water consumers during high risk events

24. Non-Immune Compromised 490 age matched case control Study International Travel OR 7.7 (C.I. 2.7-22) Contact w/ Cattle OR 3.5 (C.I. 1.8 � 6.8) Contact 2-11 w/G.I OR 3.1 (CI 1.5-6.2) Freshwater swimming OR 1.9 (CI 1.05-3.5)

25. Sampling Environmental � EPA Methods 1622 & 1623 Slow & Expensive May provide false sense of security Microscopy Biological Sampling Feces Smears � e.g., Immunofluorescence

26. Why Worry? Oocyst is highly resilient Viable in marine environment for days Detected in 90% of surface waters (source of 1/2 of U.S. drinking water)

27. Conventional Drinking Water Treatment Coagulation Flocculation Sedimentation Filtration Sand Filters: 7 - 12um Diatomaceous Earth Filters: 3 - 5um

28. Why Worry? Cont. Oocyst is tiny: 4 - 6 um Infective Dose 1 - 4 oocysts Resistant to Chlorine CT# = 9600 Standard drinking water has 0.5 ppm FAC at tap Properly Chlorinated Pool water has 1.5 ppm FAC

29. Why Worry? Cont. Average bather - ~ 0.14 gram fecal material Cryptosporidium 105-107/gr fecal material Recall: Infective Dose � 1-4 cysts Asymptomatic shedders Millions of cysts released in bowel movement Concern: Recreational Waters

30. Case Study Water Park Northern California Late 1990s Church Group Cross Contamination with Surface Waters

31. Water Treatment Options Ozone Treatment Ultraviolet light Chlorine dioxide Reverse Osmosis Distilled Filters with </ 1um pore size (absolute) �Protected� Wells

32. Recreational Waters Engineering Controls Engineer out wading pool - lap pool cross contamination Disinfection Technology Administrative Controls Disciplined pool hygiene management system Staff training & education Baby friendly changing areas in locker rooms Handwashing Signage Shower & Waterproof Swim Wear Policy (infants) �Floater� Policy Preclude individuals with diarrhea w/in 7 days Avoid swallowing water

33. Standard Recommendations Disciplined Hand Washing Cleaning at risk foods Monitoring & training of food workers Boil (1 min) or filter suspect water See Norovirus

34. Relevance to Preparedness Day Care Conditions Food Services Municipal water compromised Implement Surveillance System Co-infections Training and education

35. Environmental Health (NCEH) Everyone Everywhere All the Time

36. Resources http://www.cdc.gov/ncidod/dpd/parasites/cryptosporidiosis/2004_PDF_Cryptosporidiosis.pdf CDC National Center for Infectious Diseases, Division of Viral Gastroenteritis Section http://www.cityofsydney.nsw.gov.au/Business/documents/Health/CryptoPoolsProtocol.pdf http://www.dnr.state.wi.us/org/water/dwg/Crypto.htm http://www.epa.gov/safewater/icr.html http://www.dhpe.org/infect/norwalk.html http://en.wikipedia.org/wiki/Norwalk_virus_group http://www.cdc.gov/ncidod/diseases/submenus/sub_norwalk.htm http://www.cdc.gov/ncidod/dvrd/revb/gastro/norovirus.htm www.epa.gov/microbes http://instruct1.cit.cornell.edu/courses/biomi290/microscopycases/crypto/NewConclusion.htm http://www.cdc.gov/foodborne/publications_search.htm http://www.cdc.gov/foodborne/publications/215-r_sharon_rskfctrs_cryptoJCM2004.pdf

37. Thank you!