EPI Response Team Training: Plague

1
EPI Response TeamTraining Plague

• Paige Jordan RN, BSN
• Region II Epidemiologist

2
The Organism
3
Yersinia pestis

• Family Enterobacteriaceae
• Gram negative coccobacillus (pleomorphic)
• Aerobic, Facultatively anaerobic
• Facultative intracellular pathogen
• Survival
• Briefly in soil
• Soft tissue 1 week
• Frozen - years

4
(No Transcript)
5
History
6
History

• Outbreaks
• Justinians pandemic 540-590
• Black Death pandemic 13461400
• Great Plague of London 1665
• Hawaii, 1899
• San Francisco, 1900
• Last U.S. outbreak, 1924, Los Angeles
• 32 pneumonic cases/31 deaths

7
Black Death Pandemic

• Sudden appearance in Europe 1347
• Rattus rattus and Xenopsylla cheopis
• Quarantine
• Impact on England greatest of all countries
• Sporadic outbreaks throughout 14th century
• 17-55 million perished (1/3 of population)

8
Great Plague of London

• Began 1664
• Foundations of public health laid
• Reporting of sick persons, shutting up homes
• Lord have mercy upon us
• Killed dogs and cats
• Peak mortality of 7,000/week
• Total mortality 1/5th of pop.

9
United States

• Hawaii 1899
• San Francisco 1900
• 1924 Epidemic Los Angeles
• 32 pneumonic cases/31 deaths
• Spread throughout the western U.S.
• From Rattus norvegicus and Rattus rattus to
  sylvatic rodents
• Primarily ground squirrels

10
U.S. - First Human Cases

• California 1900
• Oregon 1934
• Utah 1936
• Nevada 1937
• Idaho 1940
• New Mexico 1949
• Montana 1987

• Arizona 1950
• Colorado 1957
• Wyoming 1978
• Oklahoma 1980s
• Texas 1920
• Washington 1907
• New York 2002

11
Plague as a Disease

• Class 1 quarantinable disease (WHO)
• CDC Division of Quarantine
• Reportable disease

12
Transmission
13
Transmission to Humans

• Flea bite 78
• Especially those associated with ground squirrels
• Direct animal contact 20
• Tissues, body fluids, scratches, bites
• Y. pestis enters through break in skin
• Aerosol (ie, cough) 2
• Cats
• Human cases, April-November

14
Flea Vectors

• Can live off host for months
• Many species can transmit
• Oropsylla montana
• Rock and California ground squirrels, prairie
  dogs
• Excellent vector
• Most important flea vector in United States

15
Flea Transmission

• ?27C (80.6F) blood clots in flea gut and
  transmission occurs more readily
• ?27C blood clot in flea gut dissolves and
  transmission less likely

16
Epidemiology
17
Where Are Cases Found?

• Southwest
• Northern New Mexico
• Northern Arizona
• Southern Colorado
• California
• Accounts for 90 of all human cases

18
Human Plague U.S. 1970-1991(295 cases)
19
(No Transcript)
20
Human Cases

• United States
• 1925-1964 41 cases, avg. 2 cases/year
• Since 1970 avg. 13 cases/year
• Worldwide
• 1,000-3,000 cases/yr
• 18,739 cases from 19801994
• 2,603 cases in 1999 from 14 countries
• 181 deaths
• Africa (76 of all cases)

21
Plague, reported human cases, U.S. 1970-2000
Prairie dog and rock squirrel epizootic
0 5 10 15 20 25
30 35 40 45
Reported Cases
1970 1975 1980
1985 1990 1995
2000 Year
22
(No Transcript)
23
Public Health Significance

• 10-15 fifteen people each year are diagnosed with
  plague in the United States
• Approx 14 (1 out of 7) of the cases of plague
  are fatal
• associated with delays in diagnosis and treatment
• Scattered in rural areas
• Associated with rats and rat fleas

24
Public Health Significance

• Seventeen cases of pneumonic plague from 1972 to
  1994 were acquired from household cats.
• There has never been a case of plague reported in
  West Virginia.

25
Public Health Significance

• 390 cases reported in US from 1947-1996
• 84 of which were bubonic
• 13 septicemic
• 2 pneumonic
• Concomitant case fatality rates were 14, 22,
  and 57 respectively (JAMA, 283(10), May 3, 2000)

26
Public Health Significance

• Because of the terrorist events of 2001
  associated with anthrax, and because large
  quantities of plague may have been weaponized, a
  bioterrorist event in which Y. Pestis is
  aerosolized cannot be ruled out. In 1970, the
  World Health Organization reported that in a
  worst-case scenario, if 50 mg of Y. Pestis was
  released as an aerosol over a city of 5 million
  people, pneumonic plague could occur in as many
  as 150,000 persons, 36,000 of whom would be
  expected to die

27
Plague Epidemiology in Nature

• Sylvatic (wild)
• Urban (domestic)
• Reservoirs
• Rock squirrels
• Ground squirrels
• Prairie dogs
• Mice
• Voles
• Others

28
Sylvatic Plague

• Enzootic
• Plague maintained at steady level in rodent
  populations
• Low death rates
• Mice, voles

29
Sylvatic Plague

• Epizootic
• Large die-offs, fleas change hosts
• Amplifying hosts prairie dogs, ground squirrels,
  rock squirrels, woodrats, chipmunks
• Expansion into human occupied areas
• Greatest threat to humans

30
Robert B. Crave. Plague. Infectious Diseases, 5th
ed. J.B. Lippincott Co. 1994.
31
Urban Plague

• Infected fleas or rodents move to urban area
• Interface areas around homes
• Western U.S. cities suburban-wilderness zone
• Commensal (domestic) rodents
• Roof rat, Norway rat
• Rat fleas may feed on humans
• Poverty, filth, homelessness

32
West Virginia

• No natural reservoir of infection in West
  Virginia
• Implications for case investigations
• Urgent investigation
• Identify potential natural exposure (travel to
  endemic area, importation/exposure to sick
  animal)
• BT

33
Plague as a Biological Weapon

• 1970 WHO estimate
• 50 kg agent
• City of 5 million
• 150,000 pneumonic cases
• 36,000 deaths
• 80,000-100,000 hospitalized
• 500,000 secondary cases
• Up to 100,000 deaths total

34
Disease in Humans
35
Human Disease

• Bubonic
• Cutaneous infection
• Swollen, tender lymph glands (buboes)
• Fever, chills, headache, exhaustion

36
Human Disease

• Septicemic
• Multiplication in bloodstream
• Fever, chills, prostration,
• abdominal pain, shock,
• bleeding into skin

37
Human Disease

• Pneumonic
• 1 4 day incubation period
• Infection of the lungs
• High fever, chills, cough, difficulty breathing,
  bloody sputum
• Most likely for BT (may also see gastrointestinal
  manifestations)
• 100 fatal if not treated early

38
Laboratory Confirmation

• Acceptable specimens
• Material from infected bubo
• Blood specimen (Series taken 10-30 minutes apart)
• Bronchial or Tracheal Wash
• Sputum (Not the best)
• Office of Laboratory Services

39
Laboratory Diagnostic TestsPLAGUE
Colonial Morphology on SBA at 72 hrs
Gram Stain
40
Plague Treatment and Prophylaxis

• Without treatment Death 2-6 days after exposure
• Treatment is effective if begun early
• Symptomatic Exposed (cough or fever)
• Streptomycin or Gentamicin
• Doxycycline or Tetracycline
• Ciprofloxacin
• Post-exposure Prophylaxis
• Doxycycline or Ciprofloxacin (7 days)
• Fever/Cough watch

41
Health Workers

• Droplet precautions
• Gown, gloves, eye protection, mask
• Post-exposure antibiotic prophylaxis

42
Response to BT Plague(Life-saving interventions)

• Early recognition and reporting
• Case-finding
• Fever or cough in known outbreak
• Early initiation of treatment
• Isolation of cases
• Contact tracing and case investigation
• Initiate post-exposure prophylaxis
• Monitor exposed for symptoms
• Antibiotic susceptibility testing

43
Training/Preparation Considerations

• Physicians and Hospitals
• Recognition, reporting, treatment, and infection
  control
• Labs
• Confirmation of clinical diagnosis
• Local Health Departments
• Investigation and pharmaceutical supply
  assessment
• State Health Departments
• Investigation, communication, support LHD, etc
• Increasing overall surveillance and reporting

44
Additional Information

• CDC, Division of Vector-borne Infectious Diseases
  http//www.cdc.gov/ncidod/dvbid/index.htm
• CDC, plague information http//www.bt.cdc.gov/agen
  t/plague/index.asp

45
Plague Surveillance Protocol
46

• Plague may occur from an unintentional exposure
  to infected rodents and their fleas or through an
  intentional exposure such as a bioterrorism (BT)
  event. When necessary this protocol addresses
  unintentional and intentional exposures
  separately otherwise the protocol applies to
  both situations. This protocol applies if a case
  of plague is highly suspected and does not apply
  to non-specific pulmonary, gastrointestinal, or
  rash illnesses.

47
Public Health Action

• Prior to the occurrence of a case of plague
• Protect employee health
• Identify high risk employees
• Educate high risk employees
• Personal Protective Equipment (PPE)
• Assemble and train BT response teams
• Assemble BT response teams
• Responsibilities of BT response teams
• Surge capacity for BT response teams
• Train BT response teams

48
Protect employee health

• Identify high risk employees
• Identify high risk employees who will be involved
  in the response to a bioterrorism (BT) event or
  may have direct contact to plague cases
• laboratory workers who test specimens and
  environmental samples
• state and local epidemiologic response teams,
  healthcare workers and support workers in
  hospitals, and EMS staff who may come into
  contact with plague cases
• hazmat teams, industrial hygienists, health
  department sanitarians, and other personnel that
  may collect environmental samples
• first responders such as law enforcement, EMS,
  and fire department personnel that respond to a
  BT event.

49
Protect employee health

• Educate high risk employees
• Educate high risk employees about plague from a
  BT event
• respiratory droplet precautions and isolation of
  cases
• Personal Protective Equipment (PPE)
• Educate employees on the use of proper PPE
• Provide appropriate PPE to employees for use
  during an outbreak
• Ensure fit testing for employees for respirator
  use
• (see Preventive interventions)

50
Assemble and train BT response teams

• Assemble BT response teams
• Identify staff for two BT response teams (an
  epidemiology response and a vaccination /
  medication team) that can adequately respond to a
  large outbreak by conducting surveillance and
  epidemiologic response and by providing
  prophylaxis or treatment after a BT event
• Responsibilities of BT response teams
• Specific team responsibilities are described in
  WV Public Health Preparedness Plan for
  Surveillance and Epidemiologic Response

51
Assemble and train BT response teams

• Surge capacity for BT response teams
• Identify pools of individuals for surge capacity
  for the response teams during large outbreaks.
  A detailed plan for surge capacity is described
  in the WV Public Health Preparedness Plan for
  Surveillance and Epidemiologic Response
• Train BT response teams
• Periodically train and pre-drill individuals on
  the teams in their respective responsibilities
  during an outbreak

52
Public Health Action

• Educate health care providers and the public in
  the recognition and diagnosis of plague
• Educate providers and laboratories to report
  plague to the local health department in the
  patients county of residence immediately
• Educate veterinarians to report confirmed or
  suspected cases of plague in animals to the West
  Virginia Department of Agriculture

53
Public Health Action

• When a plague case is reported
• Confirm cases
• Confirmation of an intentional or unintentional
  exposure and Notification Procedure
• Activate the BT response teams
• Protect employee health

54
Case Finding

• Develop a working case definition
• Begin enhanced passive surveillance
• Prepare for active surveillance
• Confirm new cases
• Develop line list of cases

55
Contact tracing

• Identify contacts
• Direct contacts
• Direct contacts are defined as any person who has
  had face-to-face contact (within 2 meters) with a
  suspected, probable, or confirmed case of plague
  during the infectious period (See Infectious
  Period section)

56
Contact tracing

• Interview all suspected, probable, and confirmed
  cases and identify all persons who had direct
  contact with the case since the cases onset of
  symptoms (henceforth referred to as a
  case-contact). Continue interviews daily and
  record contacts until case is no longer
  infectious (See Infectious Period section). For
  each case develop a line list of all
  case-contacts including all household members of
  case-contacts using plague contact tracing forms

57
Contact tracing

• Locate case contacts
• Find locating information for each case-contact.
  Use work and school telephone numbers, telephone
  directories, voting lists, neighborhood
  interviews, site visits, hangouts, etc., to
  trace case-contacts when locating information is
  unknown or incomplete. If case-contacts cannot
  be found through these mechanisms, other sources
  for notification, such as media announcements,
  may have to be considered

58
Contact tracing

• Interview case-contacts
• Interview all case-contacts and all household
  members of case-contacts including those who work
  full time in the household. Assure that all
  case-contacts are contacted within 24 hours and
  record all information on plague contact tracing
  forms

59
Maintain line listing of cases, develop risk
factor/exposure data base

• Track cases on case line list and ensure that
  clinical and laboratory information are collected
  from health providers and laboratories, if not
  done

60
continued

• Develop and maintain a data base of pertinent
  clinical and exposure data for hypothesis testing
• Compile clinical, laboratory, and exposure
  assessment data as they are collected or
  submitted by health care providers and labs.
• Review data for completeness and complete pending
  case investigations and incomplete exposure
  assessments.
• Develop and maintain electronic database for
  hypothesis testing.

61
Hypothesis testing

• Exposure assessment Conduct an assessment of
  the source and characteristics of exposure
  immediately after a case is suspected as follows
• Interview a representative sample of cases and
  obtain a complete risk factor and exposure
  history including travel/activity information
  using the Risk Factor and Exposure Form plague
  forms for travel and activities during the cases
  exposure period (1-7 days before symptom onset)
• If a possible BT event or intentional exposure
  location/source is suspected, continue the
  interview with the same sample of cases. Using
  the Suspicious Exposure Form, determine more
  detailed information, including the type,
  location and specific areas, duration, relative
  amount, and method of dissemination of exposure
  for the possible BT event

62
Hypothesis testing

• Analyze the clinical, laboratory, risk factor,
  and exposure assessment data to test plausible
  hypotheses for the source and location of exposure

63
Identify exposed population

• After the source of the exposure is confirmed,
  identify the exposed population.
• Definition of an exposed individual An exposed
  individual will be a person who shared or
  possibly shared airspace that was contaminated by
  Y. pestis, had direct contact with or inhaled
  contaminated material such as powder or other
  environmental exposures as part of a BT event, or
  shared airspace with an infected animal, or was
  bitten by infected fleas from an infected animal.

64
Identify exposed population

• Develop a line listing of all persons possibly
  exposed using the Exposed Individual Line Listing
  Form. Record each persons exposure risk based
  upon proximity to exposure.

65
Surveillance of case-contacts and exposed
population

• Interview case-contacts and exposed individuals
  Assure that all case-contacts and exposed
  individuals are interviewed within 24 hours and
  refer them to a clinical center for post exposure
  prophylaxis (PEP), as necessary (See Treatment
  Section). For large populations, alert the
  public about the location of clinical centers for
  treatment or PEP through media announcements.

66
Surveillance of exposed

• Conduct surveillance of all exposed individuals
  for
• 7 days
• If an exposed individual does not have
  signs/symptoms of plague by end of 7 days, then
  discontinue surveillance. Interview all exposed
  individuals to verify they have no symptoms, and
  if so, indicate status of exposed individual as
  closed on Exposed Individual Line Listing Form

67
Surveillance of exposed

• If exposed individual develops fever (gt38.5 C) or
  cough then assure referral for parenteral therapy
  (See Treatment Section) after cultures are
  obtained, and assure implementation of
  appropriate infection control and preventive
  interventions (See Preventive Intervention
  Section). Enter status of exposed individual as
  a case and move to Case Line List. Begin contact
  tracing for this new case

68
Surveillance of case-contacts

• Place all case-contacts under surveillance for 7
  days from day of suspected or known direct
  contact with a confirmed case
• If case-contact does not have signs/symptoms of
  plague by end of 7 days, then discontinue
  surveillance. Interview all case-contacts daily
  to verify they have no symptoms, and if so, after
  seven days, indicate status of case as closed
  on Contact Line List Form

69
Surveillance of case-contacts

• If case-contact develops fever (gt38.5C) or cough,
  then assure referral for parenteral therapy (See
  Treatment Section), and assure implementation of
  appropriate infection control and preventive
  interventions (See Preventive Intervention
  Section). Enter status of case-contact as case
  on Case Line List. Begin contact tracing for
  this new case (See B, 6)

70
Prevention and Control

• After the source has been identified, remove
  people from the environment,(e.g., contaminated
  by a BT event) until decontamination is achieved.
  
• Post exposure prophylaxis
• Because of the short incubation period, and the
  high mortality, PEP must begin before the
  investigation is complete. See Treatment Section
  for PEP guidelines. Recommend to the State
  Health Commissioner that PEP should be offered to
  all exposed and all case-contacts
• Groups of persons in which 2 or more persons have
  culture-confirmed plague (and therefore
  common-source exposure is likely or plausible).
  PEP should be offered for up to 7 days (See
  Treatment Section.)

71
Prevention and Control

• Groups of persons in which 1 person has
  culture-confirmed plague and there is a common
  environmental exposure which was confirmed
  positive for Y. pestis. PEP should be offered
  for up to 7 days
• Groups of persons in which multiple persons meet
  the suspect case definition and have onset of
  illness within 3 days. PEP should be offered for
  up to 7 days pending culture results and a final
  recommendation.

72
Prevention and Control

• Recommend to the State Health Commissioner that
  all cases should be immediately referred for
  treatment according to current guidelines (See
  Treatment Section)
• Recommend to the State Health Commissioner the
  amount of antibiotics that are needed for PEP or
  treatment.

73
Disease Prevention Objectives

• Prevent unnecessary illness and death through
• rapid identification of populations exposed to
  plague so appropriate treatment or post exposure
  prophylaxis can quickly be administered and
• adherence to infection control isolation and
  barrier guidelines via standard and droplet
  precautions

74
Disease Control Objectives

• Educate health care workers regarding the use of
  droplet precautions when dealing with pneumonic
  plague up to 72 hours following institution of
  appropriate antibiotic therapy
• Educate public to contact the West Virginia
  Department of Agriculture for the proper disposal
  of infected animals

75
Disease Control Objectives

• Educate workers that may be exposed to infected
  animals in proper hygiene and personnel
  protective measures

76
Surveillance Objectives

• To rapidly detect and confirm a case of plague
  when it occurs in WV

77
Clinical Description

• Five individual forms of plague
• Common systemic symptoms include
• headache, fever, cough, chills and progressive
  weakness.
• Accurate diagnosis of plague may be delayed by
  the presence of gastrointestinal symptoms
• nausea, vomiting, diarrhea and abdominal pain
• or absence of the classic bubo.

78
Pneumonic Plague

• The clinical symptoms involving the lungs
• cough, fever, difficulty breathing and hemoptysis
  (bloody sputum).
• Patients with pneumonic plague will require
  substantial advanced medical supportive care in
  addition to antimicrobial therapy.
• Complications of sepsis include
• adult respiratory distress syndrome, disseminated
  intravascular coagulation, shock, and multiorgan
  failure.
• Pneumonic plague is the most likely form of
  plague following a bioterrorist event

79
Plague following a BT attack

• The pathogenesis and clinical manifestations of
  plague following a BT attack would be notably
  different than naturally occurring plague
• Inhaled aerosolized Y. Pestis would cause primary
  pneumonic plague
• The time from exposure to aerosolized plague
  bacilli until development of first symptoms in
  humans and nonhuman primates has been found to be
  1 to 6 days and most often, 2 to 4 days

80
Plague following a BT attack

• The first sign of illness would be expected to be
  fever with cough and dyspnea, sometimes with the
  production of bloody, watery, or less commonly,
  purulent sputum
• Prominent gastrointestinal symptoms, including
  nausea, vomiting, abdominal pain, and diarrhea,
  might be present

81
Plague following a BT attack

• The ensuing clinical findings of primary
  pneumonic plague are similar to those of any
  severe rapidly progressive pneumonia and are
  quite similar to those of secondary pneumonic
  plague (which may develop following onset of
  bubonic or primary septicemic plague).

82
Plague following a BT attack

• Clinicopathological features may help to
  distinguish primary from secondary pneumonic
  plague
• In contrast to secondary pneumonic plague,
  primary pneumonic plague would include absence of
  buboes (except, rarely, cervical buboes), and
• On pathological examination, pulmonary disease
  with areas of profound lobular exudation and
  bacillary aggregation
• Chest radiographs are variable, but bilateral
  infiltrates or consolidation are common

83
Plague following a BT attack

• Laboratory studies may reveal
• Leukocytosis (incr. WBCs) with toxic
  granulations
• Coagulation abnormalities
• Aminotransferase elevations
• Azotemia (incr. blood urea level)
• Evidence of multiorgan failure
• All are nonspecific findings associated with
  sepsis and systemic inflammatory response
  syndrome

84
Plague following a BT attack

• The time from respiratory failure to death in
  humans is reported to have been between 2 to 6
  days in epidemics during the preantibiotic era,
  with a mean of 2 to 4 days

85
Bubonic Plague

• Most common form of naturally occurring plague
• Acute onset of fever and painful swollen lymph
  nodes (also known as buboes)
• inguinal lymph nodes are most commonly involved
• axillary or cervical lymph nodes may also be
  affected

86
Septicemic Plague

• Clinical symptoms include
• Low blood pressure
• Acute respiratory problems
• Bleeding into the skin and other organs
• usually results from a complication of bubonic or
  pneumonic plague
• When septicemic plague occurs alone, buboes do
  not develop

87
Pharyngeal Plague

• Clinically this would appear to be a viral or
  streptococcal pharyngitis, but the cervical
  lymphadenopathy associated with this would be
  much more painful and severe

88
Meningeal Plague

• Most rare form of plague
• Follows the hematogenous seeding of bacilli into
  the meninges
• Associated with symptoms of
• Fever
• Headache
• Meningismus

89
Plague

• Etiologic Agent
• Yersinia pestis is a non-motile, gram-negative
  bacillus sometimes coccobacillus
• Reservoir
• Plague is a zoonotic disease associated with
  rodents (mainly ground squirrels) and fleas.
  Rabbits, hares, wild carnivores, prairie dogs and
  domestic cats may also serve as a source of
  infection

90
Modes of Transmission

• Primary pneumonic plague is transmitted through
  airborne droplets from an infected human or
  animal (especially household cats) with
  respiratory plague or from aerosol exposure in
  the laboratory setting

91
Modes of Transmission

• The most common source of human bubonic plague is
  through the bite of an infected flea. This form
  of plague may also be transmitted less commonly
  through the direct contact or handling of
  infected tissues and fluids from animals (i.e. a
  bite or scratch from a household cat)

92
Mode of Transmission

• Septicemic plague may by transmitted by
• handling infectious materials
• the bite of an infected flea
• more commonly as a complication of bubonic or
  pneumonic plague
• Neither bubonic plague nor septicemic plague
  spreads directly from person to person

93
Mode of Transmission

• Small percentage of patients with bubonic or
  septicemic plague develop secondary pneumonic
  plague
• can then spread the disease by respiratory
  droplets
• persons contracting the disease by this route
  develop primary pneumonic plague????

94
Mode of Transmission

• Pharyngeal plague is a rare form of plague that
  may follow inhalation or ingestion of the plague
  bacilli
• Meningeal plague usually occurs as a complication
  of inadequately treated bubonic plague, but may
  occur as a primary infection. A high mortality
  is associated with this form of plague

95
Mode of Transmission

• A bioterrorist event or an intentional exposure
  would most likely occur through aerosolization of
  the plague bacillus

96
Epidemiology continued

• Incubation Period
• Signs and symptoms may develop from 2-8 days
  after- being bitten by a flea, but can be a few
  days more in individuals that have been
  previously immunized. The incubation period for
  primary plague pneumonia is 1-4 days. An
  airborne exposure (i.e., from a BT event) would
  likely cause symptoms in 1-6 days. Contacts are
  considered to be at risk for development of
  pneumonic plague for up to 7 days after exposure
  to a case with pneumonic plague

97
Epidemiology continued

• Infectious Period
• A person is infectious from onset of cough until
  48 hours after treatment with antibiotics and
  signs of clinical improvement.

98
Outbreak Recognition

• Outbreak recognition and investigation requires
  timely and complete epidemiological investigation
  paired with a timely and thorough laboratory
  investigation. As West Virginia has never
  reported a case of plague, one case is defined as
  an outbreak

99
Case Definition

• Clinical Description
• Plague is transmitted by humans, fleas, or direct
  exposure to infected tissues via respiratory
  droplets the disease is characterized by fever,
  cough, chills, headache, malaise, prostration,
  and leukocytosis that manifests in one or more of
  the following principal clinical forms
• Regional lymphadenitis (bubonic plague)
• Septicemia without an evident bubo (septicemic
  plague)

100
Case Definition

• Plague pneumonia, resulting from hematogenous
  spread in bubonic or septicemic cases (secondary
  pneumonic plague) or inhalation of infectious
  droplets (primary pneumonic plague)
• Pharyngitis and cervical lymphadenitis resulting
  from exposure to larger infectious droplets or
  ingestion of infected tissues (pharyngeal plague)

101
Laboratory criteria for diagnosis

• Presumptive
• Elevated serum antibody titer(s) to Yersinia
  pestis fraction 1 (F1) antigen (without
  documented fourfold or greater change) in a
  patient with no history of plague vaccination or
• Detection of F1 antigen in a clinical specimen by
  fluorescent assay
• Confirmatory
• Isolation of Y. pestis from a clinical specimen
  or
• Fourfold or greater change in serum antibody
  titer to Y. pestis F1 antigen

102
Case classification

• Suspected
• Clinically compatible case without presumptive or
  confirmatory laboratory results
• Probable
• Clinically compatible case with presumptive
  laboratory results
• Confirmed
• Clinically compatible case with confirmatory
  laboratory results

103
Laboratory Notes

• Specimens
• Sputum
• lymph node biopsy
• Blood
• Environmental samples should be sent to OLS for
  testing (Level B lab)

104
Laboratory Notes

• Clinical specimens should be sent to hospitals or
  level A labs for rule-out or presumptive testing
  for Y. Pestis. If Level A tests indicate
  suspicious findings consistent with Y. pestis
  isolates should be sent to OLS, a Level B lab for
  confirmation.

105
Preventive Interventions

• Person-to-person transmission of pneumonic plague
  occurs via respiratory droplets
• transmission by droplet nuclei has not been
  demonstrated
• Droplet transmission-occurs when droplets
  containing microorganisms generated from the
  infected person, primarily during coughing,
  sneezing, and talking and during the performance
  of certain procedures, such as suctioning and
  bronchoscopy, are propelled a short distance and
  deposited on the hosts conjunctivae, nasal
  mucosa, and/or mouth

106
Preventive Interventions

• Because these relatively large droplets do not
  remain suspended in the air, special air handling
  and ventilation are not required to prevent
  droplet transmission
• droplet transmission should not be confused with
  airborne transmission via droplet nuclei, which
  are much smaller

107
Recommended prevention measures

• Environmental exposure precautions
• For persons going into an environment where there
  has been an environmental contamination by
  plague, personnel should use a NIOSH approved
  self contained breathing apparatus (SCBA) in
  conjunction with a level A protective suit. Other
  guidelines see CDC, Interim Recommendations for
  the Selection and Use of Protective Clothing and
  Respirators Against Biological Agents, October
  24, 2001

108
Recommended prevention measures

• Infection control procedures
• Standard and respiratory droplet precautions are
  recommended for caring for all suspected,
  probable, or confirmed cases of plague, for close
  contacts of patients, and for handling bodies of
  deceased patients. Recommendations for infection
  control against transmission of Y. Pestis are as
  follows (JAMA, May 8, 2002, 2872391-2405)

109
Infection control procedures

• Close contacts
• Staff who have close contact with cases should
  practice standard and respiratory droplet
  precautions (surgical mask, gown, gloves, and eye
  protection). Employees and individuals coming
  into close contact with suspected or confirmed
  plague patients who have had less than 48 hours
  of antimicrobial therapy should wear surgical
  masks. Unnecessary close contact within the
  first 48 hours of therapy should be avoided

110
Infection control procedures

• Isolation of patients and close contacts
• Patients
• Patients should remain isolated during the first
  48 hours of antibiotic therapy and until clinical
  improvement occurs. If isolation is impossible
  due to a large number of patients, patients may
  be cohorted while undergoing antibiotic therapy.
  Patients being transported should also wear
  surgical masks.

111
Infection control procedures

• Close contacts
• Previous public health guidelines have advised
  strict isolation for all close contacts of plague
  patients who refuse prophylaxis. In modern
  times, pneumonic plague has not spread widely or
  rapidly within a community, and thus, isolation
  of close contacts refusing prophylaxis is not
  recommended. Instead close contacts should be
  put under surveillance for development of fever
  or cough during 7 days post exposure and treated
  immediately

112
Recommended prevention measures

• Housekeeping
• Hospital rooms of patients should receive
  terminal cleaning in a manner consistent with
  standard precautions and clothing and linens
  contaminated with body fluids should be
  disinfected.
• Laboratories
• Laboratories should observe biosafety level 2
  conditions. Activities with a high potential for
  aerosol or droplet production (centrifuging,
  grinding, vigorous shaking, animal studies)
  require biosafety level 3 conditions

113
Recommended prevention measures

• Deceased patients
• Bodies of deceased patients should be handled
  with standard and droplet precautions
• Contact with remains should be limited to trained
  personnel
• Safety precautions for transporting corpses for
  burial should be the same as those for
  transporting ill patients

114
Recommended prevention measures continued

• Aerosol-generating procedures such as bone saws
  associated with surgery or postmortem examination
  which are associated with special risks of
  transmission are not recommended. If such
  procedures are necessary, then high efficiency
  particulate air filtered masks and negative
  pressure rooms should be used

115
Preventive Interventions

• Prophylaxis
• Prophylaxis of all exposed individuals and
  contacts, and treatment of cases is recommended
  (See Treatment Section). In the U.S., there is
  no vaccine currently available for primary
  pneumonic plague. A U.S. licensed
  formaldehyde-killed whole bacilli vaccine was
  discontinued by manufacturers in 1999 and was
  effective in preventing bubonic plague

116
Preventive Interventions

• Environmental exposures
• Remove people from the environment (e.g.,
  contaminated by a BT event) until environment is
  deemed safe
• no evidence that residual Y. pestis bacilli pose
  an environmental threat to the population
  following dissemination of a primary aerosol such
  as in a BT event
• no spore forming life cycle similar to Bacillus
  anthracis.
• Y. pestis is very sensitive to sunlight and
  heating and does not survive long outside the
  host

117
Preventive Interventions

• some evidence that the bacterium may survive in
  the soil for some time, but there is no evidence
  to suggest an environmental risk to humans and
  thus no need for environmental decontamination
• WHO estimate plague aerosol was infectious for
  only 1 hour

118
Preventive Interventions

• For naturally occurring incidents, remove people
  from the source of infected cats, rodents, or
  their fleas

119
Treatment

• Recommendations based on JAMA, 283(17), May
  3,2000
• Recommendations for use of antimicrobials
  following a deliberate release of plague are made
  on the basis of limited knowledge
• A further complication is the possibility that a
  large number of people will need treatment

120
Treatment

• Contained casualty setting, where a modest number
  of people require treatment, parenteral
  antibiotic therapy is recommended
• streptomycin or gentamicin
• Mass casualty setting, intravenous or
  intramuscular therapy may not be possible, so
  oral therapy
• doxycycline (or tetracycline) or ciprofloxacin

121
Treatment

• Patients with pneumonic plague will require
  substantial advanced medical supportive care.
  Complications of gram-negative sepsis would be
  expected, including adult respiratory distress
  syndrome, disseminated intravascular coagulation,
  shock, and multiorgan failure

122
Treatment Postexposure prophylaxis (PEP)

• Tables found on page 17 18
• Management of special groups
• Breastfeeding woman Treat the mother and infant
  with the same antibiotic based on what is safe
  and effective for the baby. In the contained
  casualty setting, gentamicin is recommended. In
  the mass casualty setting, doxycycline is
  recommended. Fluoroquinolones are the
  recommended alternative

123
Treatment Postexposure prophylaxis (PEP)

• Once plague is confirmed or strongly suspected in
  a particular area, anyone in that area with fever
  (of 38.5C or higher) or cough should immediately
  be treated with antimicrobials for presumptive
  pneumonic plague. Delaying therapy until tests
  confirm plague will greatly decrease the person's
  chance of survival

124
Treatment Postexposure prophylaxis (PEP)

• Doxycycline is the first-choice antibiotic for
  PEP other recommended antibiotics are included
  in the Table.
• Asymptomatic persons who have had household,
  hospital, or other close contact (2 meters or
  less) with persons with untreated pneumonic
  plague should receive PEP for 7 days and be
  monitored for fever and cough

125
Treatment Postexposure prophylaxis (PEP)

• Tetracycline, doxycycline, sulfonamides, and
  chloramphenicol have been recommended for these
  individuals
• On the basis of mice studies, fluoroquinolones
  might also be protective

126
Treatment PEP

• Persons refusing prophylaxis should be closely
  monitored for the development of fever or cough
  for the first 7 days after exposure and should be
  treated immediately if either occurs.
• Clinical deterioration of patients despite early
  presumptive therapy could indicate antimicrobial
  resistance and should be promptly evaluated.

127
Treatment PEP

• Special measures should be taken for treatment or
  prophylaxis of those unaware of the outbreak or
  those requiring special assistance, such as
  persons who are homeless or who have cognitive
  disorders