1. Infectious Diseases and Natural Disasters

2. Background   Historically, infectious disease epidemics have high mortality   Disasters have potential for social disruption and death   Epidemics compounded when infrastructure breaks down   Can a natural disaster lead to an epidemic of an infectious disease?   Are there emerging infectious diseases after a natural disaster?

3. What is an emerging infectious disease?   In 1991, Institute of Medicine attempted to define:   – “new, re-emerging, or drug resistant infections whose incidence in humans has increased within the past 2 decades or whose incidence threatens to increase in the near future.”

4. Phases of Disaster   Impact Phase (0-4 days) – Extrication – Immediate soft tissue infections   Post impact Phase (4 days- 4 weeks) – Airborne, foodborne, waterborne and vector diseases   Recovery phase (after 4 weeks) – Those with long incubation and of chronic disease, vectorborne

5. Factors for Disease Transmission After a Disaster   Environmental considerations   Endemic organisms   Population characteristics   Pre- event structure and public health   Type and magnitude of the disaster

6. 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

7. Endemic organisms (exclusively native to a place)   Infectious organisms endemic to a region will be present after the disaster   Agents not endemic before the event are UNLIKELY to be present after   Rare disease may be more common   Unlikely a new or changed disease will occur   Deliberate introduction could change this factor

8. Population Characteristics   Density – Displaced populations – Refugee camps   Age – Increased elderly or children   Chronic Disease – Malnutrition – Heart disease – Transplantation

9. Population Characteristics   Education – Less responsive to disaster teams   Religion   Hygiene – Underlying health education of public   Trauma – Penetrating, blunt, burns   Stress

12. What infections would we see today?   Endemic organisms   Post-impact phase   Recovery Phase

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

14. Type of disaster   Earthquake – Crush and penetrating injuries (Skin and soft tissue disruption, Muscle/tissue necrosis, Toxin production disease, Burns).   Hurricane (Monsoon, Typhoon) and Flooding – Water contamination (Gastroenteritis, Cholera, Non-cholera dysentery, Hepatitis) – Vector borne diseases ( Malaria, viral encephalitis, Dengue and Yellow fever, Typhus)   Tornado – Crush (see earthquake)   Volcano – Water contamination (see Hurricane) – Airway diseases (Viral, CAP (phenomena))

15. Epidemics after Disasters San Francisco, 1907 Fires; Plague resulting from Quarantine failure Duluth, MN, 1918 Forest Fire; Influenza resulting from crowding and epidemic Italy, 1976 Earthquake; Salmonella Carriers due to sanitation stoppage

16. Summary of Factors   Many factors play a role in disease development and outbreaks   Change of disease not likely to play role – Increase in rare diseases   Change and/or closing of public health measures play a big role

17. General disaster reminders   Vaccinations are the mainstay of outbreak control in many situations   Dead bodies pose little to no infectious disease risk; however this is debated   Early surveillance and hygiene can prevent outbreaks

18. Conclusions   Infectious diseases may play a role in the post disaster period   These diseases will vary depending on many factors   If the disease is not present before the disaster, unlikely to be there after

19. Conclusions   Early recognition of certain diseases in disaster setting important   Halting infrastructure and response has led to most increases in infectious diseases   know where you are going and what is endemic