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Yersinia

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Yersinia Prepared by:-Prof.Dr.Sundus.S.Bakr * * * * Picture of bacteria Yersinia and on the agar, rod shape * Picture from the microscope Gram negative shows the red ... – PowerPoint PPT presentation

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Title: Yersinia


1
Yersinia
  • Prepared by-Prof.Dr.Sundus.S.Bakr

2
Yersinia
  • Member of Enterobacteriaceae
  • Gram negative, small rod shape
  • Y. enterocolitica,
  • Y. pseudotuberculosis,
  • Y. pestis

3
  • Cells of Yersinia are small 1mm or less on
    nutrient agar
  • Y. enterocolitica, Y. pseudotuberculosis, Y.
    pestis are the three pathogenic species
  • Y. enterocolitica and Y. pseudotuberculosis cause
    the food borne disease.
  • Y. Pestis causes the bubonic plague or black
    death in Europe

4
Yersinia
5
Yersinia
Gram-negative rods.
Small rods
6
Yersinia
Yersinia
Enterobacteriaceae
Growth of Y. enterocolitica on blood agar medium
7
Yersinia
18 hours incubation on MacConkey Agar at 37C
18 hours incubation on Yersinia entreo Selective
Agar at 37C
8
Yersinia
  • Low temperature pathogen
  • Able to grow at 4C
  • Some biochemical characteristics are temperature
    dependent
  • expose at 28-30C but not at 37C
  • Mobile below 30C but not at 37C
  • Incubation at 37C ?loss of the virulence plasmid
    plasmid mediated properties
  • Yersinia is psychrotroph.
  • So, may continue to grow under refrigeration

9
Yersinia
Influence of incubation temperature in the
motility of Y. enterocolitica
10
  • At 28C Y. enterocolitica is motile and is seen
    (arrowed) spreading away from the stab inoculums
    during growth in semi-solid medium.
  • At 37C, the org. is non-motile

11
Yersiniosis
  • Infectious disease caused by Yersinia
  • Only Y. enterocolitica and Y. pseudotuberculosis
    cause gastroenteritis
  • Symptoms
  • Gastroenteritis
  • Abdominal pain, diarrhea (often bloody) ,
    vomiting, fever
  • In older children and adults, right-sided
    abdominal pain (pseudo-appendicitis)
  • Right sided abdominal pain may be confused with
    appendicitis.
  • In a small proportion of cases, complications
    such as skin rash, joint pains, or spread of
    bacteria to the bloodstream can occur.

12
Yersiniosis
  • Onset illness, between 24 to 48 hours after
    ingestion
  • Occasional Y. enterocolitica GI infection
    followed by arthritis of peripheral joints
  • 2 - 6 weeks after intestinal infection clears
  • Called reactive arthritis (Reithers syndrome)
  • may occur even in the absence of obvious
    symptoms.

13
Yersiniosis
VS
Bacterial antigen
Arthritis of peripheral joint (post food
poisoning consequences)
  • The frequency of postenteritis arthritic
    conditions is about 2-3

14
  • Can occur with people who has human lymphocyte
    antigen B27 (HLA-B27) the antigen exposed on the
    host cell
  • Thought to be caused by T-cells and/or antibodies
  • elicited by antigens that cross-react with host
    antigens, not by infection of the joints
  • common in people with histocompatibility antigen
    HLA-B27 (exposed on surface of host cells)
  • antibodies vs. bacterial surface antigens
    cross-react with human B27, activate C'
  • T-cells recognizing B27 may attack host cells

15
Yersinia enterocolitica
  • Optimum temperature 22-29C (range of -2 to 45C)
  • Foods involved in transmission
  • Meats (pork, beef, lamb, etc.)
  • Oysters, fish
  • Raw milk
  • Prevalent in the soil and water and in animals
    such as pigs

16
Yersinia enterocolitica
  • Infected by
  • Eating contaminated food ? raw or undercooked
    pork products
  • Drinking contaminated unpasteurized milk or
    untreated water
  • Susceptibility
  • Infants, children
  • Compromised adults
  • individuals with the antigen HLA-B27
    (postenteritis arthritis)

17
Yersinia pestis
18
Hosts of Yersinia pestis
  • Mammalian
  • Human
  • Rodent
  • Insect
  • Xenopsylla cheopis

http//www.channel4.com/history/ microsites/H/hist
ory/plaegu/plague.html Science Picture Library
www.exn.ca/Stories/ 2000/09/12/52.asp
19
Symptoms
idcs0100.lib.iup.edu/ WestCivI/the8.htm
www.imcworldwide.org/ cbr/L1C-m2.html
http//aci.mta.ca/Courses/Biology/Images/bacterial
20folder/Plague.html
  • Bubonic
  • Pneumonic
  • Septicemic

www.niaid.nih.gov/dir/ labs/lhbp/hinnebusch.htm
20
Transmission Cycles The transmission cycle of Y.
pestis is vector-dependent, and is usually
dependent on X. cheopis, the rat flea
www.pon.nic.in/fil-free/ vcrc/plague.html
21
Diagnosis
  • Diagnosis is based primarily on clinical
    suspicion - USAMRIID
  • Staining
  • Culture

http//www.cdc.gov/ncidod/dvbid/plague/p4.htm
www.einsamer-schuetze.com/natur/krankheit/pest/bed
rohung.html
22
  • Diagnosis for Y. pestis is based on staining
    blood, sputum, CSF or lymph node aspirates with
    Gram, Wayson or Giemsa staining, but a definitive
    diagnosis requires a culture.
  • The green picture at the top of the slide is a
    presumptive positive confirmation via
    immunofluoresence for the presence of F1
    antigen, which is specific to the Y. pestis .The
    tan picture Is an SEM image of Y. pestis from
    culture.
  • Currently, only culturing is the definitive
    method of confirming a diagnosis of bubonic
    plague,
  • The Rapid Detection Test is being
    collaboratively developed by the WHO Coll.
    Center for Plague in Madagascar and France, as
    well as the Ministry of Health in Madagascar

23
Treatment
  • ANTIBIOTICS- streptomycin ,ciprofloxacin or
    doxycycline
  • Development of resistant strains

http//content.nejm.org/cgi/content/full/337/10/67
7
24
Pathogenesis
  • Evolution
  • Plasmids
  • Type III Secretion
  • Virulence Factors

dr-gng.dp.ua/death/ black/death_0.htm
25
Plasmids
  • pPCP1 interferes with blood coagulation.
  • pPMT1 have a role in resisting monocytic
    phagocytosis.
  • pCD1 the most important plasmid necessary for
    virulence in Y. pestis.

http//tecfaetu.unige.ch/wiki/index.php/PrincipeTr
ansgenese
26
Type III Secretion
  • Yersinia pestis relies on Type III secretion for
    many of its anti-immune system properties
  • A major component of Type III secretion is the
    Injectisome
  • Yops inhibit phagocytosis

27
Virulence Factors
  • Invasins
  • Tyrosine Phosphatase
  • , Y. pestis is well equipped to both avoid
    phagocytosis and to deal with engulfment

http//www.jbc.org/cgi/content/full/280/11/10388
28
Detection
  • Rapid Detection Test
  • The RDT is a test sensitive to the presence of
    the plague-specific F1 antigen using monoclonal
    antibodies.

www.allwestselectsires.com/ ecf.asp
www.testsymptomsathome.com/ TEC01.asp
29
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