Infectious Disease Issues in Natural Disasters

1. Infectious Disease Issues in Natural Disasters Christian Sandrock, M.D. UC Davis School of Medicine

3. Overview • Discuss the role of infectious diseases in natural disasters (flood, earthquake, hurricane, etc) • Look at the factors effecting the development of disease outbreak after a disaster • Discuss specific diseases seen after various disasters • Review efficacy of various treatment options

4. Is there a link? • Conflicting belief among experts as to rise in disease after disaster • Some studies relate direct link between disaster and disease outbreak (Dominican Republic- hurricane) • Others offer theory but no link • All depends on variable factors

12. Background • Historically, infectious disease epidemics have accounted for large number of deaths • Disasters have potential for large number of deaths • Epidemics are still viable and feared • Can a natural disaster lead to an epidemic?

13. Phases of Disaster • Impact Phase (0-4 days) • Extrication • Some immediate soft tissue infections • Post impact Phase (4 days- 4 weeks) • Airborne, foodborne, waterborne diseases • Recovery phase (after 4 weeks) • Those with long incubation and of chronic disease Western K Tropical Public Health, London School of Hygiene and Tropical Public Health

14. Variables for Development of an Epidemic After a Disaster • Environmental considerations • Endemic organisms • Population characteristics • Pre- event structure and public health • Type and magnitude of the disaster

15. Endemic organisms • The organisms are endemic to the region before the disaster • If not present before the event, it will not be there after regardless of ecological conditions • Deliberate introduction could change this factor

16. Environmental Considerations • Climate • Cold- airborne • Warm- waterborne • Season (USA) • Winter- influenza • Summer- enterovirus • Rainfall • El Nino years increase malaria • Drought-malnutrition-disease • Geography • Isolation from resources

17. Endemic Organisms • Northridge Earthquake • Ninefold increase in coccidiomycosis (Valley fever) from January- March 1994 • Mount St. Helens • Giardiasis outbreak in 1980 after increased runoff in Red Lodge, Montana from increased ash

21. Population Characteristics • Density • Displaced populations • Refugee camps • Age • Increased elderly or children • Chronic Disease • Malnutrition • DM, heart disease • transplantation

22. Population Characteristics • Education • Less responsive to disaster teams • Religion • Polio in Nigeria, 2004 • Hygiene • Underlying health education of public • Trauma • Penetrating, blunt, burns • Stress

25. Pre-event resources • Sanitation • Primary health care and nutrition • Disaster preparedness • Disease surveillance • Equipment and medications • Transportation • Roads • Medical infrastructure

31. Type of disaster • Earthquake • Crush and penetrating injuries • Hurricane (Monsoon, Typhoon) and Flooding • Water contamination, vector borne diseases • Tornado • Crush • Volcano • Water contamination, airway diseases • Magnitude • Bigger can mean more likelihood for epidemics

32. Epidemics after Disasters

33. Epidemics after Disasters

34. Flooding • Missouri 1993 • Increase reports if E.D. visits due to illness • 17% GI, 20% respiratory • Iowa 1993 • No reports of GI increase due to sanitationmeasure • Florida – Hurricane Andrew • Heavy mosquito spraying lead to no change in encephalitis rates Howard et al, Emergency Medicine Clinics in North America 1996 14 (2)

35. Dominican Republic, 1979 • Hurricane David and Fredrick on Aug 31 and Sept 5th 1979 • >2,300 dead immediately • Marked increase in all diseases measured 6 months after the hurricane • Thyphoid fever • Gastroenteritis • Measles • Viral hepatitis Bissell, RA J Emerg Med 1983 1 (1):59-66

40. What epidemics would predominate today? Endemic organisms Post-impact phase Recovery Phase

41. Post-Impact Phase Infections • Crush and penetrating trauma • Skin and soft tissue disruption • Muscle/tissue necrosis • Toxin production disease • Burns • Waterborne • Cholera • Non-cholera dysentery • Hepatitis • Rare diseases

42. Post-Impact Phase Infections • Vector borne • Malaria • Encephalitis • Dengue and Yellow fever • Typhus • Respiratory • Viral • CAP • Rare disease • Other • Blood transfusions

43. Recovery Phase Infections • These agents need a long incubation period • TB • Schistosomiasis • Lieshmaniasis • Leptospirosis • Nosocomial infections of chronic disease

44. Skin and Soft Tissue Disease • Crush and penetrating injuries • ABC’s • Establish airway • Circulation • Stabilize • BP support • Respiratory support • Diagnose extent of injuries • Radiology • Diagnostic procedures • Corrective action • CT, fracture stabilization, transfusion • Surgery if necessary

45. Skin and Soft Tissue Disease • Post-traumatic Care • Hypoxia from pulmonary contusion, ARDS, VAP • Coagulopathy • Renal failure • DVT/PE • Ulcer disease • Soft tissue infections • Cellulitis • Necrotizing fasciitis • Post op wound infection • Burn care

49. Cellulitis • Skin infection involving the subcutaneous tissue • Predisposing factors • Lymphatic compromise • Site of entry • Obesity • DM • Microbiology • Streptococci, Groups A, B, C, G • Staphylococcus aureus • Others

50. Cellulitis • Pathogenicity • Not well understood • Venous and lymphatic compromise • Bacterial invasion with endo/exotoxin release • Cytokine release • Symptoms • Systemic- F/C/M • Redness, swelling • Tenderness, edema • May have ulcer or abscess