Infectious Diseases After Natural Disasters

1
Infectious Diseases After Natural Disasters

• Christian Sandrock, MD, MPH
• California Preparedness Education Network
• Funded by HRSA Grant T01HP01405

2
CALIFORNIA PREPAREDNESS EDUCATION NETWORK
A program of the California Area Health
Education Centers
3
calPEN at COMMUNITY HEALTH PARTNERSHIP

• Covers the 9 San Francisco Bay Area counties
• It is a program of the Health Education and
  Training Center (South Bay AHEC), a division of
  the Community Health Partnership
• Community Health Partnership is a consortium of
  community clinics that works to strengthen the
  healthcare safetynet for the medically underserved

4
HOUSEKEEPING

• Folder contents
• Sign-in sheet with degree/job function and
  license number (if applicable)
• Please FILL OUT the participant data form and the
  evaluation form and TURN IN by the end of the
  presentation

5
OBJECTIVES

• 1. Recognize the risk of infectious diseases
  after natural disasters
• 2. Recognize the indications of infectious
  diseases after natural disasters
• 3. Meet immediate care needs of patients
• 4. Alert appropriate authorities
• 5. Participate in response

6
(No Transcript)
7
Overview

• The role of infectious diseases in natural
  disasters
• Factors leading to a disease outbreak after a
  disaster
• Review some of the common and rare diseases after
  a natural disaster

8
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?
• If so, how?

9
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

10
(No Transcript)
11
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

12
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

13
Endemic organisms

• 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
• Deliberate introduction could change this factor

14
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

15
(No Transcript)
16
Population Characteristics

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

17
Population Characteristics

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

18
(No Transcript)
19
(No Transcript)
20
Pre-event resources

• Sanitation
• Primary health care and nutrition
• Disaster preparedness
• Disease surveillance
• Equipment and medications
• Transportation
• Roads
• Medical infrastructure

21
(No Transcript)
22
(No Transcript)
23
(No Transcript)
24
(No Transcript)
25
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

26
Flooding

• Missouri 1993
• Increase reports if E.D. visits due to illness
• 20 respiratory,17 GI
• Iowa 1993
• No reports of GI or respiratory increase due to
  sanitation measures
• Florida Hurricane Andrew
• Heavy mosquito spraying lead to no change in
  encephalitis rates

27
Dominican Republic, 1979

• Hurricane David and Fredrick on Aug 31 and Sept
  5th 1979
• gt2,300 dead immediately
• Marked increase in all diseases measured 6 months
  after the hurricane
• Thyphoid fever
• Gastroenteritis
• Measles
• Viral hepatitis

28
Epidemics after Disasters
29
Epidemics after Disasters
30
(No Transcript)
31
Summary of Factors

• Many factors play a role in disease development
  and outbreaks
• Change of disease not likely to play role
• Change and cessation of public health measures
  play a big role

32
What infections would we see today?

• Endemic organisms
• Post-impact phase
• Recovery Phase

33
Post-Impact Phase Infections

• Crush and penetrating trauma
• Skin and soft tissue disruption (MRSA)
• Muscle/tissue necrosis
• Toxin production disease
• Burns
• Waterborne
• Gastroenteritis
• Cholera
• Non-cholera dysentery
• Hepatitis
• Rare diseases

34
Post-Impact Phase Infections

• Vector borne
• Malaria
• WNV, other viral encephalitis
• Dengue and Yellow fever
• Typhus
• Respiratory
• Viral
• CAP
• Rare disease
• Other
• Blood transfusions

35
Recovery Phase Infections

• These agents need a longer incubation period
• TB
• Schistosomiasis
• Lieshmaniasis
• Leptospirosis
• Nosocomial infections of chronic disease

36
What effects skin and soft tissue infections?

• Crush and penetrating injuries
• ABCs
• Establish airway
• Circulation
• Stabilize
• BP support
• Respiratory support
• Diagnose extent of injuries
• Radiology
• Diagnostic procedures
• Corrective action
• CT, fracture stabilization, transfusion
• Surgery if necessary

37
What effects skin and soft tissue infections?

• 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

38
(No Transcript)
39
(No Transcript)
40
(No Transcript)
41
Cellulitis

• Skin infection involving the subcutaneous tissue
• Predisposing factors
• Lymphatic compromise
• Site of entry
• Obesity
• DM
• Dirty/contaminated wound

42
Cellulitis- Microbiology

• Streptococcus
• Staphylococcus (MRSA)
• Worse in shelters
• Special circumstances
• Water exposure
• Aeromonas (MMWR 2005 Sept54(38)961 and Clin
  Infect Dis 2005 Nov41(10)93)
• Vibrio vulnificus (MMWR 2005 Sept54(38)961)
• E coli, Klebsiella, Pseudomonas (Lakartidningen
  2005 Nov102(48)3660)
• Myroides, Bergeyella, Sphingomonas
• Mucormycosis (Ann Acad Med Singapore 2005)

43
Cellulitis- Microbiology

• Animal bites
• Pasteurella multocida
• DM
• Other gram negatives
• Asia
• Increased resistance (Lakartidningen 2005
  Nov102(48)3660)
• Leprosy (Emerg Infect Dis 2005 Oct11(10)1591-3)
• Chemical dermatitis (MMWR 2005 Sept54(38)961)

44
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

45
(No Transcript)
46
(No Transcript)
47
Cellulitis

• Treatment
• Antibiotics (MRSA)
• B-lactam
• TMP/SMX
• Clindamycin
• Linezolid
• Vancomycin
• Limb elevation
• Systemic support
• Surgical consultation
• Abscess
• Occular
• Necrotizing fasciitis evaluation

48
Necrotizing Fasciitis

• Fulminant destruction of tissue
• Systemic toxicity
• Very high mortality
• Much larger bacterial load than cellulitis
• Travels through fascial plain
• Much less inflammation from necrosis, vessel
  thrombosis, and bacterial factors

49
Necrotizing Fasciitis

• Two types
• Type I
• Largely mixed aerobic and anaerobic infection
• Seen in post surgical patients
• DM, PVD big risk factors
• Examples
• Cervical necrotizing fasciitis (Ludwigs angina)
• Fourniers gangrene
• Type II
• Group A strep
• Large exotoxin production or M protein
• Any age group or without portal of entry

50
Diagnosis

• Pain
• May mimic post surgical changes
• Skin changes
• Thick or woody in nature
• Minimal erythema
• Bullae
• Systemic symptoms
• Fevers, chills
• Rapid sepsis

51
(No Transcript)
52
(No Transcript)
53
(No Transcript)
54
(No Transcript)
55
(No Transcript)
56
(No Transcript)
57
Treatment

• Surgical Debridement!!!!!!!!
• aggressive and explorative
• Wide tissue excision
• Antibiotics
• B- lactam antibiotics
• Clindamycin for toxin production
• Gram negative/anaerobic coverage
• Hyperbaric O2
• Supportive care

58
Toxin Diseases

• Tetnus
• Rare due to vaccination
• 1 Million die per year in developing world
• 4 clinical patterns
• Generalized
• Local
• Cephalic
• Neonatal

59
Tetanus

• Spores of C. tetani enter the tissue
• Produce metalloprotease, tetanospasmin
• Retrograde movement into CNS
• Blocks neurotransmission by cleaving protein
  responsible for neuroexocytosis
• Disinhibition of motor cortex
• Extensive spasm

60
Tetanus

• Needs the right factors to produce
• Penetrating injury with spore delivery
• Co-infection with other bacteria
• Devitalized tissue
• Localized ischemia
• Can have water contamination as part of entry
  (Ann Acad Med Singapore 200534(9)582)

61
(No Transcript)
62
Tetanus Treatment

• Wound management
• Halts toxin production
• Tetanus antitoxin and vaccine
• Neutralized unbound toxin
• Benzodiazepines and paralytics
• Treats spasms
• B-blockers
• Treats autonomic dysfunction of late disease
• Supportive care

63
(No Transcript)
64
Waterborne disease

• Viral gastroenteritis
• Norovirus (MMWR 2005 Oct54(40)1016)
• Cholera
• Gram negative bacterium Vibrio cholerae
• Severe water diarrhea with 50 mortality if
  untreated
• 190 serrotypes but only O1 and O139 cause human
  epidemics
• Bacterial model for toxin mediated disease
• 2 cases isolated after Katrina with minimal
  disease (MMWR Nov 2005)

65
Cholera pathophysiology

• Enter the small bowel and colonize
• Pilus required
• Hemagglutanins
• Acessory colonizing factor
• Porin like proteins
• Produces toxin
• A with 5 B subunits
• A cleaves to A1, activates adenylate cyclase
• Leads to increase Cl secreation and decreased Na
  absorption

66
Cholera-symptoms

• Majority are asymptomatic
• Some with develop rapid diarrhea
• Diarrhea most severe days 1-2, stops by day 6
• May loose 100 body weight in 2 days
• Children, elderly at risk
• Death in 2 -48 hours (18 average)

67
Cholera Treatment

• Oral rehydration- per liter
• 3.5g NaCl
• 2.9g NaHCO3
• 1.5g KCl
• 20g glucose
• IV rehydration
• Antibiotics- not necessary
• Lessens diarrhea by one day
• Vaccine- no evidence
• Public health prevention

68
Non cholera dysentery

• Giardia
• E. Coli
• Toxin Mediate food poisoning
• Salmonella
• Shigella
• Campylobacter
• Yersinia
• Viral hepatitis
• Viral Gastroenteritis

69
(No Transcript)
70
(No Transcript)
71
(No Transcript)
72
(No Transcript)
73
Respiratory Illness

• Viral
• Most common cause of infectious illness after
  Midwest floods over past 20 years
• More common is shelter setting (unpublished)
• TB
• 25 mortality in camps in Africa and Asia
• Worsened by drought
• Community acquired bacterial pneumonia
• Mainly theoretical, no data

74
Recent experiences

• Meliodosis (Emerg Infect Dis 2005
  Oct11(10)1639)
• Necrotizing pneumonia
• Multidrug resistant TB (Emerg Infect Dis 2005
  Oct11(10)1591-3)
• Atypical mycobacterial pneumonia (Emerg Infect
  Dis 2005 Oct11(10)1591-3)

75
Vector borne disease

• Malaria
• Common after flooding (Prehospital disaster Med
  200217(3)126)
• Brackish water increases Anopheles (Malar J
  20054(1)30)
• Well controlled with mosquito abatement
• Encephalitis
• No documented increase in US but heavy abatement
  programs
• West Nile?

76
General disaster reminders

• Vaccinations are the mainstay of outbreak control
  in many situations
• Dead bodies pose little to no infectious disease
  risk (Rev Panam Salud 200415(5)297-9)
• Early surveillance and hygiene can stem outbreaks

77
Conclusions

• Infectious diseases may play a role in the post
  disaster period
• These diseases will vary depending on many
  factors
• If the disease if not present before the
  disaster, it will not be there after

78
Conclusions

• Early recognition of certain diseases in disaster
  setting important
• Halting infrastructure and response has led to
  most increases in infectious diseases
• If deployed, know where you are going and what is
  endemic

79
QUESTIONS?

• Please remember to complete
• Personal data sheet
• Evaluation
• Sign-in sheet (include your degree or job
  function AND your license number if applicable to
  receive CEUs)

80
(No Transcript)