Plague is an infectious disease caused by Yersinia pestis bacteria, usually found in small mammals and their fleas. The disease is transmitted between animals via their fleas and, as it is a zoonotic bacterium, it can also transmit from animals to humans.

1. PLAGUE
Kuldeep Vyas
Asst. Prof. Community HealthKuldeep Vyas M.Sc. CHN 1

2. HISTORY
•Y. PESTIS WAS
DISCOVERED IN 1894
BY ALEXANDRE YERSIN,
A SWISS/FRENCH
PHYSICIAN AND
BACTERIOLOGIST
FROM THE PASTEUR
INSTITUTE, DURINGAN
Kuldeep Vyas M.Sc. CHN 2

3. HISTORY
• IMPORTANCE
• ONE OF THREE WHO QUARANTINABLE
DISEASES
• ESTIMATED 200 MILLION DEATHS
RECORDED
• THREE PRIOR PANDEMICS
• JUSTINIAN 541AD
• BLACK DEATH 1346
• CHINA1855
Kuldeep Vyas M.Sc. CHN 3

4. MICROBIOLOGY
• TAXONOMY
• FAMILY
ENTEROBACTERIACEAE
• 11 YERSINIA SPECIES
–3 HUMAN
PATHOGENS
• Y. PESTIS
• Y. PSEUDOTUBERCULOSIS
• Y. ENTEROCOLITICA
4
Kuldeep Vyas M.Sc. CHN 4

5. HUMAN Y.PESTIS INFECTION
•HUMAN Y. PESTIS INFECTION TAKES THREE
MAIN FORMS: PNEUMONIC, SEPTIC EMIC, AND
BUBONIC PLAGUES ALL THREE FORMS WERE
RESPONSIBLE FOR A NUMBER OF HIGH-
MORTALITY EPIDEMICS THROUGHOUT HUMAN
HISTORY, INCLUDING THE JUSTINIANIC PLAGUE
OF THE SIXTH CENTURY AND THE BLACK
Kuldeep Vyas M.Sc. CHN 5

6. •STANNING
•GRAM NEGATIVE
COCCOBACILLUS
•GIEMSA, WRIGHT,
WAYSON STAINS –
BIPOLAR “SAFETY
PIN” STAINING
Image courtesy of CDC
MICROBIOLOGY
Kuldeep Vyas M.Sc. CHN 6

7. Kuldeep Vyas M.Sc. CHN 7

8. HISTORICAL DOCUMENTATION
• ONE OF THE FIRST MENTIONS
OF THE PLAGUE IN HISTORY
WAS IN THE YEAR A.D.541.
DURING THAT TIME IT WAS
CALLED JUSTINIAN'S PLAGUE
AFTER THE EMPEROR. IT TOOK
THE LIVES OF APPROXIMATELY
200,000 PEOPLE. THAT WAS IN
ABOUT A FOUR MONTHPERIOD.
FOR ABOUT SEVEN HUNDRED
YEARS JUSTINIAN'S PLAGUE
WENT AWAYAND REAPPEARED
EVERY TEN TO TWENTY-FOUR
YEARS. JUSTINIAN'S PLAGUE
Kuldeep Vyas M.Sc. CHN 8

9. RAT FLEA XENOPSYLLA CHEOPSIS
• WHEN BITE BLOOD
REGURGITATE TO BITE WITH
CONTAMINATED FECES
• WHEN RAT DIES FLEAS FLEE
START BITING HUMANS
• COMMON IN NORTH INDIA X
CHEOPSIS
• COMMON IN SOUTH INDIA X
ASTIA
Kuldeep Vyas M.Sc. CHN 9

10. PATHOGENESIS
• ENVIRONMENTAL SURVIVAL
• REQUIRES HOST
• DOES NOT SURVIVE IN ENVIRONMENT WELL
• CAN LIVE WEEKS IN WATER, GRAINS, MOIST SOIL
• LIVES MONTHS/YEARS AT JUST ABOVEFREEZING
TEMPERATURE
• LIVES ONLY 15 MINUTES IN 55 C
• LIVES IN DRY SPUTUM, CORPSES, FLEAFECES
• INACTIVATED BY SUNLIGHT IN A FEWHOURSKuldeep Vyas M.Sc. CHN 10

11. PATHOGENESIS
•HIGHLY VIRULENT AND INVASIVE
•FOUR ROUTES HUMAN DISEASE
• FLEA-BITE (MOST COMMON)
• HANDLING INFECTED ANIMALS- SKIN
CONTACT, SCRATCH, BITE
• INHALATION – FROM HUMANS ORANIMALS
• INGESTING INFECTED MEAT
Kuldeep Vyas M.Sc. CHN 11

12. HOW THE PLAGUE SPREADS
Kuldeep Vyas M.Sc. CHN 12

13. PATHOGENESIS
•INTRACELLULAR ORGANISM
• SURVIVES IN MONOCYTES/MACROPHAGES
•INHALATION (PNEUMONIC FORM)
• DEPOSITION INTOALVEOLI
• CLASSIC LOBULAR PNEUMONIA
•RESULTING MANIFESTATION
• LIQUEFACTION NECROSIS, RESIDUAL SCARRING
Kuldeep Vyas M.Sc. CHN 13

14. CLINICAL FEATURES
•THREE TYPES
OF DISEASE
•BUBONIC
•SEPTIC EMIC
•PNEUMONIC
Kuldeep Vyas M.Sc. CHN 14

15. CLINICAL FEATURES
• BUBONIC
• MORTALITY
• 40-60% UNTREATED, <5% TREATED
• OVERALL CASE FATALITY 14% IN U.S.
• USUALLY FROM DELAYED DX AND RX
• COMPLICATIONS
• OFTEN DEVELOP BACTEREMIA
• SOME DEVELOP:
• SEPTICEMIA (SECONDARY SEPTICEMIC PLAGUE)
• PNEUMONIC (SECONDARY PNEUMONIC PLAGUE)
• MENINGITIS
Kuldeep Vyas M.Sc. CHN 15

16. CLINICAL FEATURES
• SEPTICEMIC
• HISTORICALLY 12.6% U.S. CASES ARE 1º SEPTICEMIC
• SECONDARY IF COMPLICATION OF BUBONIC
• IF CLINICAL SEPSIS DEVELOPS
• PRIMARY IF NO BUBOES DETECTED
• MORE DIFFICULT TO DIAGNOSE
• MAY GAIN ACCESS THROUGH BREAKS IN SKIN
• MAY BE FLEA-BITE WITHOUT BUBO DETECTABLE
Kuldeep Vyas M.Sc. CHN 16

17. 17
Bubonic
Septicaemic
Pneumonic
Kuldeep Vyas M.Sc. CHN 17

18. BUBONIC PLAGUE BUBON - GROIN
• INCUBATION 2 – 5 DAYS
• LYMPH NODES ENLARGE
FROM SITE OF ENTRY FROM
BITE OF RAT FLEAS
• THE LYMPH NODES
ENLARGE SUPPURATE
• BACTERIA CAN ENTER
BLOOD AND PRODUCE
SEPTICEMIA
• HEMORRHAGES INTO SKIN
AND MUCOUS MEMBRANES
• FATAL IN 30 – 90 % IF
UNTREATED. Kuldeep Vyas M.Sc. CHN 18

19. SEPTICEMIC PLAGUE
CAN LEAD TO TERMINAL
EVENT
• MENINGITIS
INVOLVEMENT
• DIC MAY LEAD TO
GANGRENE OF SKIN,
FINGERS, AND PENIS
Kuldeep Vyas M.Sc. CHN 19

20. CLINICAL FEATURES
• PNEUMONIC
• NUMBERS
• APPROX. 2% ALL PLAGUE IN
U.S. ARE 1º PNEUMONIC
• 12% ARE SECONDARY
PNEUMONIC
• USUALLY SMALL % OF CASES
IN ENDEMIC AREAS
• SECONDARY IF PRECEDING
BUBONIC (MOST CASES) OR
SEPTICEMIC Kuldeep Vyas M.Sc. CHN 20

21. MAJOR MANIFESTATIONS IN PLAGUE
Kuldeep Vyas M.Sc. CHN 21

22. CLINICAL FEATURES
•PNEUMONIC
• PRIMARY IF RESULT OF
DROPLET INHALATION
• FROM OTHER PNEUMONIC
PLAGUE PATIENTS OR INFECTED
ANIMALS
• FORM EXPECTED IF
AEROSOLIZED AS ABIOWEAPON
• EXTREMELY INFECTIOUS
VIA DROPLETS AND
PURULENT SPUTUM
Kuldeep Vyas M.Sc. CHN 22

23. PNEUMONIC PLAGUE
• GET BY DROPLET
INFECTION,
HEMORRHAGIC
PNEUMONIA
• CYANOSIS AMAJOR
MANIFESTATION
• ON EXAMINATION OF
SPUTUM SHOWS MANY
BACTERIA
Kuldeep Vyas M.Sc. CHN 23

24. CLINICAL FEATURES
•OTHER
COMPLICATIONS
• MENINGITIS
• CUTANEOUS DISEASE
• PHARYNGEAL DISEASE
• ENTERIC DISEASE
• SUSTAINED OCCULT FEVER
FROM ABSCESSED
INTRAABDOMINAL BUBOESKuldeep Vyas M.Sc. CHN 24

25. EPIDEMIOLOGY
• THREE FORMS OF PLAGUE
• BUBONIC
• SEPTICEMIC
• PNEUMONIC
• HUMAN PLAGUE MOST COMMONLY
OCCURS WHEN PLAGUE-INFECTED
FLEAS BITE HUMANS
• ANY SUSPECTED CASE IN NON-
ENDEMIC AREAS WITHOUT RISK
FACTORS – REPORT IMMEDIATELY
Kuldeep Vyas M.Sc. CHN 25

26. EPIDEMIOLOGY
• ZOONOTIC DISEASE
• RODENTS – RAT FLEAS
SPREAD
• BACILLI MULTIPLY IN
STOMACH OF FLEA
• BLOCK PROVENTRCULARIS
• 2 WEEKS EXTRINSIC
INCUBATION
• BITE IF INFECTIVE,
Kuldeep Vyas M.Sc. CHN 26

27. Kuldeep Vyas M.Sc. CHN 27

28. SEASONAL SPREAD
• COOL HUMID ENVIRONMENTS HELP
• URBAN PLAGUE
• WILD SYLVA TIC PLAGUE
• MICROBES SURVIVE IN BURROWS
• RATS SPREAD 1 RATTUS
NORVEGICUS (SEWER RAT)
2 RATTUS RATTUS
DOMESTIC
NOT POSSIBLE TO ERADICATE Kuldeep Vyas M.Sc. CHN 28

29. DIAGNOSIS
• NO RAPID TESTS AVAILABLE – TREAT FIRST
• REPORT SUSPECTED CASES TO LOCAL HEALTH DEPT. IF
NO RISK FACTOR FOR NATURALLY OCCURRING DISEASE
• SEND OUT SAMPLES IF NOT DONE IN HOSPITAL
• OBTAIN SPECIMENS AS INDICATED:
• BLOOD – ATTEMPT 4 SAMPLES Q30 MIN
• BUBO ASPIRATE (INJECT 1-2CC SALINE ANDASPIRATE
WITH 20 GA NEEDLE)
• SPUTUM
• CSF Kuldeep Vyas M.Sc. CHN 29

30. BACTERIOLOGICAL DIAGNOSIS IS GOLD STANDARD
Kuldeep Vyas M.Sc. CHN 30

31. DIAGNOSIS
• CXR
• INOCULATE ON/IN INFUSION BROTH, BLOOD AGAR,
MCCONKEYAGAR
• BIOCHEMICAL PROFILES IF AUTOMATED SYSTEM HAS
CAPACITY TO DETECT
• STAINS – GRAM AND WAYSON’S OR GIEMSA
• DFATESTING
• ACUTE SERUM FOR F1 ANTIBODY
Kuldeep Vyas M.Sc. CHN 31

32. TREATMENT
• ANTIBIOTICS
• GENERAL
• CONTAINED CASUALTIES – IV
• MASS CASUALTIES – PO EQUIVALENT, SAME AS
POST-EXPOSURE PROPHYLAXIS
• ALSO NEED INTENSIVE SUPPORTIVE CARE
• VENTILATION
• PRESSORS USUALLY NOT NEEDED
• WHO TO TREAT
• SUSPECTED CASES
• INDEX
• IF SUSPECTED RELEASE – ANYONE WITH FEVER,Kuldeep Vyas M.Sc. CHN 32

33. TREATMENT
• SPECIAL POPULATIONS
• CHILDREN
• SAME AS ADULTS BUT TRY AVOID TCN IF <8YO
• NO CHLORAMPHENICOL FOR <2 YO (GREY BABY SYNDROME)
• PREGNANT WOMEN
• TRY TO AVOID STREPTOMYCIN
• 1ST CHOICE GENTAMICIN, SAME ADULT DOSE
• 2ND CHOICE DOXY, SAME ADULT DOSE
• 3RD CHOICE CIPRO, SAME ADULT DOSE
• BREASTFEEDING WOMEN
• SAME RECOMMENDATIONS AS PREGNANT
• IMMUNOSUPPRESSED – NO DIFFERENT THAN COMPETENT
Kuldeep Vyas M.Sc. CHN 33

34. TREATMENT
• ANTIBIOTICS FOR CONTAINED CASUALTIES
• (FOR MASS CASUALTIES, SAME AS PEP)
• 1ST CHOICES
• STREPTOMYCIN - FDA-APPROVED
• 30 MG/KG IM DIVIDED Q8-12 KIDS (MAX 2G/DAY)
• 1G IM BID ADULT
• BACTERICIDAL
• GENTAMICIN –AS EFFECTIVE, MORE AVAIL, QD DOSING
• 5MG/KG IV QD, W/LEVELS OR LOAD 2MG/KG THEN 1.7MG/KG Q8
• 2.5MG/KG IM/IV Q8H KIDS (Q12HR FOR <1WK OR PREMATURE)
Kuldeep Vyas M.Sc. CHN 34

35. TREATMENT
• 2ND CHOICES
• TETRACYCLINE'S - AS GOOD IN VITRO, GOOD HUMAN
DATA
• DOXYCYCLINE
• SINGLE 200MG IV LOADING DOSE (SOME SOURCES)
• 100MG IV BID OR 200 MG IV QD ADULTS& KIDS >45KG
• 2.2MG/KG IV Q12HR (MAX 200MG) KIDS <45KG
• BETTER ABSORPTION, DISTRIBUTION, HALF-LIFE
THAN TCN
• 1ST CHOICE PO THERAPY FOR MASS CASUALTIES
• TETRACYCLINE
• 500 MG PO QID ADULTSKuldeep Vyas M.Sc. CHN 35

36. TREATMENT
•2ND CHOICES
• FLUOR QUINOLONES–BETTER IN VITRO, NO HUMAN
DATA
• CIPROFLOXACIN
• 400 MG IV Q12HRADULTS
• 15 MG/KG IV Q12HR KIDS (MAX 1G/DAY)
• LEVOFLOXACIN
• OFLOXACIN
• CHLORAMPHENICOL
• 1ST CHOICE FOR MENINGITIS +/-AMINOGLYCOSIDE
• CROSSES BLOOD-BRAIN BARRIER
• 25MG/KG IV Q6HR ADULTS & KIDS, KEEP LEVEL 5-20 ΜG/ML
• AVOID IN KIDS <2 YO (GREY BABY SYNDROME)Kuldeep Vyas M.Sc. CHN 36

37. PREVENTION
• VACCINATION - BUBONIC
ONLY
• KILLED VIRULENT STRAIN –
USED IN U.S.
• FORMALIN-FIXED, NO LONGER
COMMERCIALLYAVAILABLE
• FUTURE PRODUCTION AND
LICENSURE UNKNOWN
• SERIES
• 3 PRIMARY (1.0CC, 0.2 CC AT1-3
MO AND 5-6 MO LATER)
• 2 BOOSTERS 0.2CC AT 6 MO
Kuldeep Vyas M.Sc. CHN 37

38. PREVENTION
• VACCINATION
• INDICATIONS
• LAB WORKERS WITH FULLY VIRULENT
STRAINS
• MILITARY PERSONNEL STATIONED IN
ENDEMIC AREAS
• EFFICACY
• BASED ON WWII (0 CASES) AND
VIETNAM (3 CASES) TROOPS
• PROTECTS VS. BUBONIC ONLY, NOT
PNEUMONIC
• ADVERSE EFFECTS
• SIGNIFICANT NUMBER HAVE MILD
REACTIONS Kuldeep Vyas M.Sc. CHN 38

39. BIOWEAPON POTENTIAL
• DELIVERY MECHANISM
• AEROSOL
• BIOWEAPONS PROGRAMS
DEVELOPED TECHNIQUES
TO AEROSOLIZE PLAGUE
DIRECTLY
• PNEUMONIC FORM WOULD
BE EXPECTED
• PROVEN INFECTIVITY OF
PRIMATES
Kuldeep Vyas M.Sc. CHN 39

40. INFECTION CONTROL
• MECHANISM FOR PERSON-PERSON SPREAD
• NOT COMPLETELY UNDERSTOOD
• RESPIRATORY DROPLETS MOST LIKELY, NOT DROPLET
NUCLEI
• HISTORICALLY PREVENTED BY MASKS
• RESPIRATORY DROPLET PRECAUTIONS
• WEAR MASK, GOWN, GLOVES, EYE PROTECTION
• SUSPECTED CASES - ISOLATE
• IMMEDIATELY RESPIRATORY (EVEN FOR BUBONIC)
• AVOID UNNECESSARY CLOSE CONTACT 1ST 48 HRS OFABX
• DURATION
• 2 DAYS AFTER INITIATING ANTIBIOTICS AND CLINICALLY IMPROVED
• AFTER SPUTUM CULTURES NEGATIVE
Kuldeep Vyas M.Sc. CHN 40

41. INFECTION CONTROL
• RESPIRATORY DROPLET
PRECAUTIONS
• MASK DURING TRANSPORT
• CAN COHORT IF NOT ENOUGH
ROOM
• CONTACTS – CONSIDER ISOLATION
• RECOMMENDED FOR THOSE
RECEIVING PEP
• DURING1ST 48 HRS OF RX
• NOT RECOMMENDED FOR
THOSE REFUSING PEP
• BUT STILL OBSERVE 7 DAYS
Image: National Library of Medicine
Kuldeep Vyas M.Sc. CHN 41

42. INFECTION CONTROL
•NATIONAL CONTROL
PROGRAMS
• SURVEILLANCE
• EARLY
DIAGNOSIS, TREATMENT
& ISOLATION OF CASES
• ENVIRONMENTAL
SANITATION &
EXPOSURE AVOIDANCE
• PUBLIC EDUCATION
• NON-ERADICABLE Kuldeep Vyas M.Sc. CHN 42

43. NEVER FORGET PLAGUE CAN OCCUR ANYWHERE DO MINIMAL
EVALUATIONS TO DIAGNOSE
• SUDDEN, SEVERE PNEUMONIA IN PREVIOUS HEALTHY
• HEMOPTYSIS
• GI SYMPTOMS
• PNEUMONIA ON CXR
• BIPOLAR STAINING GRAM- ROD IN SPUTUM, BLOOD
• PNEUMONIC PERSON-TO-PERSON TRANSMISSION
• 3RD GEN CEPHALOSPORINS INEFFECTIVE – USE
AMINOGLYCOSIDE
• REPORT SUSPECTED CASES TO HEALTH DEPTS.
Kuldeep Vyas M.Sc. CHN 43

44. Thank You …
Kuldeep Vyas M.Sc. CHN 44