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Bordetella
Dave Warshauer, Ph.D
Wisconsin State Laboratory of Hygiene
Phone: 608-265-9115
[email protected]
January 11, 2012
WISCONSIN STATE
LABORATORY
OF HYGIENE
WISCONSIN
STATE
LABORATORY OF HYGIENE
Bordetella species
•
•
•
•
•
•
•
•
B. pertussis--------------human
B. parapertussis--------human/sheep
B. bronchiseptica------animals/human
B. holmesii--------------human
B. avium-----------------birds
B. hinzii------------------poultry
B. trematum------------animals
B. petrii------------------environmental
WISCONSIN STATE
LABORATORY OF HYGIENE
2
Bordetella
• Small gram-negative coccobacillus
• Strictly aerobic (except B. petrii)
• Oxidize amino acids
– None ferment carbohydrates
• Catalase positive
• Optimal growth at 35°C, ambient air with
humidity
• B. pertussis most fastidious of the
Bordetella
– Inhibited by constituents in media
•
•
•
•
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LABORATORY OF HYGIENE
Fatty acids
Metal ions
Sulfides
Peroxides
3
B. Pertussis Gram Stain
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Some virulence factors of B. pertussis
• Non-invasive bacterium-does not normally
invade cells
• Attachment
– Filamentous hemagglutinin (FHA) and pertactin
– Pertussis toxin
• Toxins
– Tracheal cytotoxin – cell death
– Endotoxin – cytokines, fever
– Adenylate cyclase/hemolysin – inhibits lymphocyte
function
– Lipooligosaccharide (endotoxin)
– Pertussis toxin (PT)* - inhibits immune cells
chemotaxis
and acts as an adhesin
* = difference between pertussis and parapertussis
WISCONSIN STATE
LABORATORY OF HYGIENE
5
Whooping Cough
• Bordetella pertussis
• Classical whooping cough
– Cold-like illness (Catarrhal phase)
• Runny nose, sneezing, low-grade fever, tired
– Dry non-productive cough for >2 weeks
– “Whooping” cough (Paroxysmal phase)
• Severe cough with vomiting
– Severe disease in infants
– 7-10 day incubation (range 5-21)
– Epidemic disease every 2-5 years
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LABORATORY OF HYGIENE
6
Parapertussis
• Symptoms are similar to pertussis but
typically milder.
– cough that occurs in sudden, uncontrollable bursts
• Shorter duration than pertussis (Avg 14 days)
– high-pitched whooping sounds when breathing in
after a coughing episode
– posttussive vomiting
• Incubation & Transmission Periods similar to
pertussis
• All age groups can be infected.
– Young infants (e.g., <6 months of age) may have
a more severe course
• Rarely, death can occur in infants with
underlying health problems or those that are
co-infected with B. pertussis.
WISCONSIN STATE
LABORATORY OF HYGIENE
7
Pertussis CSTE Case Definition
• Clinical case definition
– Cough > 2 weeks and at least one
symptom: paroxysms, whoop, posttussive
vomiting
• Case classification
– Confirmed cases
• Culture positive
• Clinical case and PCR positive
• Clinical case and epi-linked to confirmed case
– Probable case
• Only meets the clinical case definition
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8
Transmission
• Respiratory droplets
• Highly infectious
– 80-90% of household contacts
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9
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Bordetella pertussis
• 20-40 million cases/year worldwide
• 200,000-400,000 deaths
– Primarily among children
• Cases/yr in the US
–
–
–
–
–
–
–
2002----------9,771
2003----------11,647
2004----------25,827
2005----------25,616
2006----------15,632
2007----------10,454
2008----------13,278
WISCONSIN STATE
LABORATORY OF HYGIENE
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WISCONSIN STATE
LABORATORY OF HYGIENE
12
Number of Specimens Positive for
Whooping Cough (6/1/03 – 10/22/05)
75
Number Positive
60
45
30
15
0
10/22/05
9/24/05
8/27/05
7/23/05
7/2/05
6/4/05
5/7/05
4/9/05
3/12/05
2/12/05
1/15/05
12/18/04
11/20/04
10/23/04
9/25/04
WISCONSIN STATE
LABORATORY OF HYGIENE
8/28/04
7/31/04
7/3/04
6/5/04
5/8/04
4/10/04
3/13/04
2/14/04
1/17/04
12/20/03
11/22/03
10/25/03
9/27/03
8/30/03
8/2/03
7/5/03
6/7/03
Bordetella parapertussis
Bordetella pertussis/Bordetella bronchiseptica
Bordetella pertussis
Bordetella pertussis/parapertussis
13
WISCONSIN STATE
LABORATORY OF HYGIENE
14
WISCONSIN STATE
LABORATORY OF HYGIENE
15
WISCONSIN STATE
LABORATORY OF HYGIENE
16
Pertussis Vaccine
• Included in childhood vaccines
– DTaP at 2,4,6, and 15-18 months, 4-6
years
– Recent addition-------Tdap at 11-12 years
– “Catch up” for 13-18 yr olds
• Issue of “waning immunity”
WISCONSIN STATE
LABORATORY OF HYGIENE
17
Treatment and Prophylaxis
• Macrolides
– Azithromycin
– Erythromycin
– Clarithromycin
• Second choice =
sulfa drugs (SXT)
• Not for infants <2mo
NOTE: Treatment should be administered during the catarrhal stage to
lessen illness. If cough develops, does not affect illness course
but may lessen transmission possibility.
WISCONSIN STATE
LABORATORY OF HYGIENE
18
Specimen Collection
• Nasopharyngeal specimen
– Want ciliated epithelial cells
– Timing critical
• NP aspirates, washes, or swabs
• Dacron or rayon swabs
– NO cotton or calcium alginate swaps
• NO throat, sputum, or mouth
specimens
WISCONSIN STATE
LABORATORY OF HYGIENE
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Nasopharyngeal Specimen
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LABORATORY OF HYGIENE
20
Transport
• B. pertussis extremely labile
• Direct culture optimal, not feasible
• Transport media
– If <2hr----0.5-1.0% Casamino Acid Sol’n at room
temp
– 2hr – 24hr----Amies with charcoal, room temp
– >24hr----Regan-Lowe or Jones-Kendrick at 4°C
WISCONSIN STATE
LABORATORY OF HYGIENE
21
Laboratory Diagnosis
• Culture
• DFA
• Real-time
Polymerase
Chain Reaction
– More rapid than
culture
– More sensitive
than culture
WISCONSIN STATE
LABORATORY OF HYGIENE
22
Laboratory Diagnosis
CULTURE
DFA
PCR
WISCONSIN STATE
LABORATORY OF HYGIENE
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Culture
• “Gold Standard”
– Essential for public health labs
• 100% specific, but low sensitivity
– (12-60%)
• Highest yield
– Young children
– Unvaccinated
– Early in cough illness prior to antibiotics
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LABORATORY OF HYGIENE
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Culture Media
• Bordet-Gengou
– Potato infusion, glycerol, sheep/horse blood
• Regan-Lowe
– Charcoal agar, 10% horse blood
• Jones-Kendrick
– Charcoal agar, yeast extract, starch
• Stainer-Scholte synthetic medium
• Legionella buffered charcoal yeastextract
• Incorporate antibiotics to suppress normal
flora----cephalexin or methicillin
• Incubate 35-36C with high humidity for a
minimum of 7 days
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LABORATORY OF HYGIENE
25
B. pertussis on Bordet-Gengou
7 days incub. Commercial Medium
“Pearl-like”
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LABORATORY OF HYGIENE
26
Other Bordetella species
• B. parapertussis
– Colonies within 2-3 days
– On Regan-Lowe appear grey
– On BG have brown pigmentation
• B. holmesii
– Colonies similar to B. pertussis
– Inhibited by cephalexin
• B. bronchiseptica
– Colonies within 1 day
– On Regan-Lowe, large, slight brown
WISCONSIN STATE
LABORATORY OF HYGIENE
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Culture Sensitivity
• Considered no more than 60% sensitive
• Factors effecting sensitivity
– Type and quality of specimen
– Time specimen obtained in the course
of illness
– Age of the patient
– Appropriate transport
– Choice of culture media
– Length of time cultures incubate
WISCONSIN STATE
LABORATORY OF HYGIENE
28
Culture for Public Health
• Important if an outbreak is suspected
• Isolation of the organism confirms
pertussis
– Other agents can cause pertussis-like
illness
– Co-infection with other pathogens occurs
– Culture helps identify other Bordetella
spp.
• Necessary for AST and subtyping
WISCONSIN STATE
LABORATORY OF HYGIENE
29
Identification
• B. parapertussis
• B. Pertussis
–
–
–
–
–
–
–
–
Catalase
Oxidase
Urease
Motility
Nitrate
Blood Agar
MacConkey
Fluor. Ab
WISCONSIN STATE
LABORATORY OF HYGIENE
+
+
-
–
–
–
–
–
–
–
–
Catalase
Oxidase
Urease
Motility
Nitrate
Blood Agar
MacConkey
Fluor. Ab
+
+
+
V
30
Direct Fluorescent Antibody
• In use since 1960
• Direct detection and ID of isolates
Courtesy of Mike Saubolle, PhD
WISCONSIN STATE
LABORATORY OF HYGIENE
31
DFA
• Problems
–
–
–
–
–
Poor sensitivity (18-78%)
Requires large numbers of organisms (>104 /ml)
Best when test early in course of illness
Requires skilled and experienced microscopist
Antibiotic therapy can affect binding of DFA
reagent to cell wall
– Poor specificity (7-44% false positives)
• Advantage
– More rapid than culture
• No longer recommended
WISCONSIN STATE
LABORATORY OF HYGIENE
32
Pertussis PCR
• Optimal diagnostic test
– 70 – 90% Sensitivity
• No prolonged asymptomatic “carrier
state”
– If positive, considered diagnostic
• Recognized by CSTE as official
laboratory confirmation of pertussis in
addition to culture
WISCONSIN STATE
LABORATORY OF HYGIENE
33
Pertussis PCR (cont.)
• Advantages
– Rapid
– Extremely sensitive
• <=1 CFU (5ul sample)
– Does not require viable organism
• Transport delays and antibiotics do not prevent
laboratory diagnosis
– Positive longer than culture
– Specific
• Except for detection of B. holmesii if using IS481
WISCONSIN STATE
LABORATORY OF HYGIENE
34
Pertussis PCR (cont.)
• Disadvantages
– Stringent requirements to perform PCR
– Not presently standardized
– More expensive than culture or DFA
– PCR inhibitors
– Cross reaction with B. holmseii
WISCONSIN STATE
LABORATORY OF HYGIENE
35
WSLH Pertussis Data
July 2003-July 2004
%Pos of Total % of Positives
3330 Tested by Culture and PCR
450 Pos by Cult and/or PCR
13.5%
100%
167 Pos by BOTH Cult and PCR
5.0%
37.1%
0.8%
6.0%
7.7%
56.9%
27 Pos by Culture ONLY
256 Pos by PCR ONLY
20 culture positive for B. parapertussis
WISCONSIN STATE
LABORATORY OF HYGIENE
36
PCR Crossing Points vs Culture
June 1, 2003- September 10,2004
73.6
68.4
80
% Culture Positive
70
60
46.5
50
40
* No. Specimens
53*
30
21.2
95*
127*
10
20
226*
10
10*
0
13-24.99
25-29.99
30-34.99
35-39.99
40-45
Crossing Point Range
WISCONSIN STATE
LABORATORY OF HYGIENE
37
1200
800
Number Tested
Number of Specimens Tested for Bordetella
by PCR and/or Culture (6/1/03 – 1/29/05)
2000
1600
400
0
1/29/05
1/15/05
1/1/05
12/18/04
12/4/04
11/20/04
11/6/04
10/23/04
10/9/04
9/25/04
9/11/04
8/28/04
8/14/04
7/31/04
7/17/04
7/3/04
6/19/04
6/5/04
5/22/04
5/8/04
4/24/04
4/10/04
3/27/04
3/13/04
2/28/04
2/14/04
1/31/04
1/17/04
1/3/04
12/20/03
12/6/03
11/22/03
11/8/03
10/25/03
10/11/03
9/27/03
9/13/03
8/30/03
8/16/03
8/2/03
7/19/03
7/5/03
6/21/03
6/7/03
Total Tested
38
WISCONSIN STATE
LABORATORY OF HYGIENE
Bordetella spp. PCR at WSLH
• Multi-target RT-PCR
– B. pertussis
– B. parapertussis
– B. holmesii
• Targets
– IS481
– plS1001
– hIS1001
– ptxS1
WISCONSIN STATE
LABORATORY OF HYGIENE
39
Targets
• IS481
– B. pertussis (80-200 copies/cell)
• hIS1001
– B. holmesii (3-5 copies/cell)
• pIS1001
– B. parapertussis
• RNP
– Inhibition detection
• ptxS1---Not part of multi-plex
– Single copy in B. pertussis and B. parapertussis
WISCONSIN STATE
LABORATORY OF HYGIENE
40
Species Identification
Species
B. pertussis
B. parapertussis
B. pertussis and
B. parapertussis
B. holmesii
WISCONSIN STATE
LABORATORY OF HYGIENE
ptxS1
IS481
hIS1001
pIS1001
+
+
+
+
+
-
+
+
-
+
+
-
41
Pertussis Serology
• Require acute and convalescent specimens
• Infection in vaccinated individuals
confounds interpretation
• Not included in CSTE case definition
• Can have epidemiologic value
• No standardized assays
• No FDA approved assays
• New CDC developed EIA may provide a
useful serologic tool
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42
CDC IgG Anti-PT ELISA
• Microwell ELISA format
• Allows for diagnosis of recent
infections with a single specimen
• Useful in later stages of the disease
(>2 weeks from onset
• Post-vaccination antibody levels do not
interfere with diagnosis
• Can be qualitative
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Bordetella holmesii
• First identified in 1995
• Associated with pertussis-like
respiratory disease and pneumonia
– 0.6% of patients
– Role in respiratory disease still unclear
• Bacteremia in asplenic children and
sickle-cell patients
– Endocarditis
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Bordetella holmesii (cont.)
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Bordetella holmesii (cont.)
• Gram negative coccobacillus
• Grows well on SBA in 5% CO2 after
24hr
– Inhibited by cephalexin
• Diffusible brown pigment
– Can be mistaken for alpha hemolysis
• Poor or no growth on Mac
WISCONSIN STATE
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46
Bordetella holmesii (cont.)
• Negative for catalase (variable),
oxidase, NO3 reductase, urease,
indole, motility
• Misidentified as Acinetobacter lwoffii
on Vitek 2
WISCONSIN STATE
LABORATORY OF HYGIENE
47
Bordetella bronchiseptica
WISCONSIN STATE
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48
Bordetella bronchiseptica (cont.)
• Rarely isolated from respiratory
specimens
• Pertussis-like disease and other
respiratory symptoms
– Infectious bronchitis
• Most frequently in imunocompromised
• Rare cases of bacteremia and
septicemia
WISCONSIN STATE
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49
Bordetella bronchiseptica (cont.)
• Has genes for pertussis toxin
– Not expressed
• Positive for catalase, oxidase, nitrate,
urease, motility
• Grows on Mac, SBA
– On SBA, small to medium gray colonies
with beta hemolysis under the colonies
WISCONSIN STATE
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50
Bordetella bronchiseptica (cont.)
WISCONSIN STATE
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Bordetella bronchiseptica (cont.)
• Susceptibility pattern
– Beta-lactamase producer
• R to many penicillins and cephalosporins
• Anti-pseudomonal penicillins usually sensitive
– Mostly resistant to SXT
– Most S to amoxicillin-clavulanic acid,
tetracycline, gentamicin, and quinolones
WISCONSIN STATE
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Thank You
Questions????
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