Management of a Cryptosporidiosis Outbreak in the South East – Lessons Learned

1. Management of a Cryptosporidiosis Outbreak in the South East – Lessons Learned Dr BethAnn Roch Dr Ann Marie O’Byrne Consultants in Public Health Medicine, HSE-SE On behalf of the Incident Response Team

2. Outline of Presentation • Description of outbreak • Results • Action taken • Discussion • Issues arising • Lessons learned

4. Problem Identification • Trigger: 4 cases of cryptosporidiosis in a 3 week period in Carlow • Notifiable disease in ROI since Jan 2004 Immediate actions • Enhanced surveillance • Contact PEHO  County Council • Contact GPs  advise vulnerable i.c. to boil water  AIG to send stool samples • Meeting convened between HSE-SE and County Council

5. Epidemic Curve

6. Descriptive Epidemiology • 31 laboratory confirmed cryptosporidiosis • 18 females, 13 males: 8 cases hospitalised

7. Geographical Distribution of Cases

8. Enhanced Surveillance • Other risk factors • crèche contacts (8) • swimming pool (5) • private wells (9) • animals (14) • travel (3) • 11 had no RF other than town water

9. Results • Water results • Cryptosporidium 0.04/10L • Giardia 0.02/10L • Microbiology clear • Faecal results • 31 laboratory confirmed cases • 7 samples sent for genotyping: C. hominis

10. Actions • Regular meetings of IRT • Swimming pool sampling and advice • Private wells sampled • Crèche visits and advice • Council water measures • Water sampling • Risk assessments • Boil notice • Programme of works to minimise risk

12. Issues arising • Water • Advice to vulnerable populations • Communication

13. Cryptosporidium species • Faecal • C. hominis • Water • C. parvum • C. andersoni • C. muris • Implications – reassurance? • Intermittent excretion, small dose infective dose • Immunocompromised • Evidence of breakthrough

14. An ‘acceptable’ level • Sampling • Volume 500-1000L • Grab/continuous • 2 filters/3 labs • Standards • UK • NI and Scotland • Types identified • Virulence of C hominis • Nature of source • Decision – 0.05 oocysts/10L

15. Cryptosporidium

16. Clostridium perfringens Source: Carlow County Council

17. C. perfringens and Cryptosporidium

18. Turbidity Grab sample of final water turbidity In line turbidity of filter outlet Standard 1 NTU Source: Carlow County Council

19. Rainfall levels & onset of illness

20. Advice to vulnerable populations • Infants • Widespread availability/use of bottled water • FSAI recommendations • Immunocompromised • Advised through medical professionals • Recommendations • UK and USA • Proposed Irish guidelines • Recommendations of IRT

21. Communication • Proactive • Council meetings • Press interviews • Notice distribution and updates • Helpline • Website • FAQs • Links • Website www.carlow.ie

22. Communication - interagency • Health Service and County Council • IRT – engineers, EHOs, public health doctors, surveillance scientists, microbiologist • Protocol for microbiological incidents • Water Liaison group meetings • Reports written in collaboration • Presentations supported • Regular meetings • Update protocol

23. Lessons learned • Interpretation of water results • Advice to vulnerable groups • Importance of communication • Building good working relationships • Management of water incidents is complex and requires input from several different disciplines.

24. Acknowledgements • HSE-SE staff & Carlow County Council • Dr Phil Jennings, A/DPH, HSE-M • Dr Derval Igoe/Dr Paul McKeown, HPSC • Dr Maire O’Connor, Consultant in PHM, HSE-E • Dr Gordon Nichols, Deputy Head, Environmental & Enteric Diseases Dept, HPA • Dr David Stewart, DPH, EHSSB • Ms Gemma Leane, HSE-SE