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Home , Bordetella pertussis, Francisella, Haemophilus ducreyi, Haemophilus influenzae, Whooping cough

Legionella Francisella

1 Dr. Goudarzi Important fastidious group of gram-negative coccobacilli include:

Haemophilus Legionella Bordetella Brucella Francisella

2 Source or site of

Respiratory tract:  Haemophilus, Legionella, Bordetella

Animal sources: Brucella, Francisella, Pasteurella, Yersinia

3

HAEMOPHILUS

Coccobacillus Non-motile Blood needed for growth Polymorphism Able to ferment Growth in BHIA

4

HAEMOPHILUS INFLUENZAE

• properties

- Small gram-negative rod ()

- Capsule (one of the 3 important encapsulated pyogens along with pneumococcus and meningococcus).

- 6 serotypes based on the capsule antigenic structure (Hib) containing a polyribitol phosphate capsule 5 6 7 FACTORS

• Capsule

• Outer membrane components: OMP & LOS

• IgA proteases:

8

For lab growth, the bacterium needs 2 components: heme (Factor X) and NAD (Factor V).

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HAEMOPHILUS INFLUENZAE VS PARAINFLUENZAE

Two growth factors: 'X' (haem) and 'V' (NAD):

H. influenzae requires both, H. parainfluenzae requires only the 'V' factor.

10 PATHOGENESIS

IgA protease degrading secretory IgA  facilitating attachment to the respiratory mucosa  entering the bloodstream  spreading to the meninges.

It also causes , or . In some people resulting in colonization.

11 12

13 CLINICAL FINDING

Meningitis: , headache, stiff neck along with drowsiness.

Sinusitis and otitis: Pain in the affected area

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15 CLINICAL FINDING

H. is second causative agent for , Sinusitis and Otitis after pneumococcus. Pneumonia in eldely adults can be caused by untypeable (non-encapsulated) strains.

16 Most infections occur in children between the ages of 6 months and 6 years.

The peak age: 0.5-1 year old due to a decline in maternal IgG.

17 18 19 LAB DIAGNOSIS

Coccobacillus Isolation on heated-blood () Capsular swelling (quellung) reaction test. Fluorescent-antibody staining

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21 H. INFLUENZAE

This organism would be identified as H. influenzae because it is using both X and V factors. 22 H. PARAINFLUENZAE

This organism would be identified as H. parainfluenzae because it is using V factor only. 23 HAEMOPHILUS SATELLITE PHENOMENON

24 TREATMENT

Untreated H. influenzae meningitis has a fatality rate of 90% , ,

25 PREVENTION prophylaxis by Rifampin to reduce respiratory carriage.

Vaccination: Two recently licensed for use with infants:

1. Haemophilus b Conjugate ( CRM 197 Protein Conjugate) (HbOC)

2. Haemophilus b (Meningococcal Protein Conjugate) (PRP-OMP)

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 Causative agent of or soft (STD), highly contagious

 Specimens should be collected from base of lesion, inoculated directly to enriched media and held for 5 days

appears as groups of coccbacilli that resemble a „school of fish” or “railroad tracks”

 Requires only X factor to grow 27

Bordetella

28 BORDETELLA

Coccobacillus Gram negative Strictly aerobic Fastidious Capsule Motile or nonmotile Bipolar in staining Colonies: haemolyses, small, smooth and convex

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• A non-motile Gram negative • Urease-negative, Oxidase-positive • Fastidious

• Incubation: high CO2 concentration, 35c, 7 days • Needs: blood (20-30%), potato extract, and glycerol • Bordetella pertussis causes pertussis or whooping

30 VIRULENCE FACTORS

• (PTx) • Filamentous haemagglutinin (FHA) • Pertactin • Fimbriae • Tracheal cytotoxin factor (TCF) • Dermonecrotic toxin • • Endotoxin

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32 PATHOGENESIS

All virulence factors together causing: 1. Cilia paralysis and prevent them from clearing debris from the lungs, so the body responds by sending the host into a coughing fit.

2. Inflammation and necrosis and reduction of phagocytic activity to help promote infection.

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34

Only a human It typically attacks children This disease is highly contagious.

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36

CLINICAL FINDINGS STAGE 1 (CATARAL)

During the first stage, common symptoms of whooping are similar to those of a cold or flu and can include: • Sneezing • Runny nose • Nasal congestion • Slight fever • Dry cough.

37 STAGE 2: PAROXYSMAL ()

• Lasts about 2 weeks and the symptoms get worse: • Skin turning blue during coughing episodes.

• Severe coughing leads to , which may make it difficult for a person to eat or drink

• Severe coughing may end in a "whooping" sound when the infected person inhales

38 39 LAB SAMPLES

Isolation from throat/nasopharynx swabs taken during the cataral and paroxysmal stage.

40 LAB DIAGNOSIS

41 L AB DIAGNOSIS

Culture on Bordet-Gengou medium (blood, potato extract, and glycerol, with an antibiotic such as cephalexin or ) Biochemical tests Agglutination with specific antiserum Fluorescent-antibody staining

42 43 TREATMENT

Erythromycin Inhalation of warm moist air, and tapping of the chest to loosen debris in the lungs Gamma globulin

44 PREVENTION

Active (killed B. pertusis and acellular): D.P.T. vaccine in ages 2, 4, 6, 18 monthes, and then at 6 year ages

Prophylaxis by

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 Non-motile, fastidious  Urease-positive, Oxidase-negative  Similar symptoms to B. pertussis but tends to be less severe.  Bordetella parapertussis may also cause pneumonia in sheep.

46 BORDETELLA BRONCHISEPTICA

47 BORDETELLA BRONCHISEPTICA

It typically infects the respiratory tracts of smaller mammals (cats, dogs, rabbits, etc).

48 Legionella

49 LEGIONELLA

• Gram negative • For growth it needs iron and cysteine • Most important species: L. pneumophila and L. micdadei • Causes Legionellosis

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51 PATHOGENESIS o Associated with environmental water sources, such as water-cooling towers and air conditioners. o Portal of entry is the respiratory tract. o High risk factors: elder people, smokers, alcohol consumers, cancer, immunosuppression (renal transplants) o Person-to-person spread does not occur. 52

53 CLINICAL FINDINGS

• Clinical picture can vary from a mild influenza like illness to a severe pneumonia • Cough is a prominent symptom but is frequently scanty and nonpurulent • Most cases resolve spontaneously in 7-10 days.

54  Two forms of infections:

 An influenza-like illness (referred to as )

 Severe form of pneumonia (i.e., legionnaires disease)

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56

 Legionellosis must be distinguished from other similar , such as Mycoplasma pneumonia, viral pneumonia, psittacosis, and .

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58

59 LAB DIAGNOSIS

• Samples can be sputum, blood or lung biopsy. • The organism fails to grow on ordinary media. • Significant increase in antibody titer by indirect immunofluorescence assay.

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61 Growing this fastidious organism on medium supplemented with iron and cysteine.

Demonstrating Legionella antigens in infected lung tissue by using fluorescent-antibody staining.

Urinary Antigen Tests

62 TREATMENT

Erythromycin

63 PREVENTION

Reducing cigarette and alcohol consumption Eliminating aerosols from water sources Reducing Legionella in hospital water supplies by using high temperatures and hyperchlorination.

64 Brucella

65 Microbiology characteristics

 Small bacilli  Gram negative  Aerobic  Capsule  Nonmotile

 Co2 needed  Fastidious

66 BRUCELLA

• Most clinical isolates come from blood cultures (Castenada’s media which has both a solid and a liquid phase)

• Requires enriched media containing meat infusion or tryptone

• Will grow on , Brain-heart infusion (BHI), Tryptone Soy Agar (TSA), Columbia blood agar (CBA) or chocolate agar

• Growth is slow and may take 72 hours 67 TRANSMISSION: A zoonotic organism

 From domestic animals:  B. melitensis from goat  B. abortus from cow  B. suis from pig  B. canis from dog  Entering routes: Mouth, conjunctive, respiratory tract, abraded skin.

68 69 BRUCELLA

• B. abortus requires 10% CO2 for growth, others do not • Grow in the presence of the dyes basic fuchsin and thionine

• H2S produced by B. abortus and B. suis • Nonfermentative • Urease +\ + • Oxidase +

70 Antigenic structure  2 antigens that are part of the LPS are recognized: A and M

71 • Causes or undulent fever in man following ingestion of contaminated milk or cheese from:

• Goats (B. melitensis), • Cows (B. abortus), • Pigs (B. suis), • Canines (B. canis).

72 ROUTES OF ENTRY

Oral - most common route  Ingestion of contaminated animal products (often raw milk or its derivatives)  contact with contaminated fingers Aerosols  Inhalation of  Contamination of the conjunctivae Percutaneous infection through skin abrasions or by accidental inoculation

73 Can affect any organ or organ system

74 CLINICAL FINDINGS

Hepatomegaly Undulant (rising and falling )fever Sweating, weakness and Severe limb and back pains Influenza like onset

75 CONTROL Pasteurizing milk Eradicating infection from herds by of animals and slaughtering of infected animals. Using safety precautions (protective clothing and laboratory safety).

76 CLINICAL AND LAB DIAGNOSIS

77 LABORATORY DIAGNOSIS

 History of exposure.  Blood sample: Enriched culture media and

incubation in 10% Co2.  Blood cultures are positive in early disease, but is the mainstay of diagnosis.

78 LABORATORY DIAGNOSIS Isolation of organism  Blood, bone marrow, other tissues Serum agglutination test  Four-fold or greater rise in titer (Wright (1/80), coombs wright (1/640), 2-ME (1/40))  Samples 2 weeks apart Immunofluorescence  Organism in clinical specimens PCR

79 CROSS-REACTIVITY

 Antibodies directed against other genera of bacteria (e.g., some strains of Escherichia, Salmonella, Vibrio, Yersinia, Stenotrophomonas, and Francisella) are also reported to cross-react with the Brucella antigen

 Antibodies directed against these bacteria cross-react with dideoxy-α-D-mannopyranosyl residues of LPS.

 Using of the a 32KD protein of brucella shows no cross reactivity (with monoclonal antibody).

80 TREATMENT some times combined with streptomycin for 21 days

CNS cases treat 6-9 months

81 Francisella

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• Causative agent of or rabbit fever.

• Facultative intracellular bacterium.

• Due to its ease of spread by aerosol and its high virulence, classified as a Class A bioterrorism agent.

• Non-motile

• Encapsulated 83 VIRULENCE FACTORS o Strains produce different hemolytic agents, which may facilitate degradation of the phagosome.

84 RABBIT FEVER

Tularemia, also known as “rabbit fever,” Tularemia is typically found in animals, especially rodents, rabbits, and hares. Tularemia is usually a rural disease

85 TRANSMISSION

F. tularensis is capable of infecting a number of small mammals such as voles, rabbits, and muskrats, as well as humans.

86 87 No human-to-human transmission TULAREMIA

 Ulceroglandular tularemia

 Oculoglandular tularemia

 Pure glandular form

 Pneumonic tularemia

 Typhoidal tularemia

 Oropharyngeal tularemia

88 TREATMENT Streptomycin is the drug of choice. Gentamicin Live attenuated vaccine

89 NUCLEIC ACID–BASED TESTS

 Polymerase chain reaction (PCR)-based assays are available for theses groups of gram-negative coccobacilli.

 With high sensitivity and good specificity.

90 Thanks

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