GRAM POSITIVE SPORE-BEARING ROD

BACILLUS CEREUSBACILLUS ANTHRAX

BACILLUS• ENDEMIC • SOIL-WATER,AIR,VEGETATION DWELLING• AEROBES• CELLS: 1-3 um• SQUARE ENDS• LONG CHAINS• SPORE: CENTRAL• NON MOTILE/MOTILE• Mesophile: 20-40 0 C

culture

BA:Beta hemolytic coloniesMotile: swarms

Bacillus cereus

BACILLUS CEREUS

• GROWS IN FOOD from soil: plants, eggs, meat, dairy; spore-dose 105-108/ gm of food

• Food poisoning: toxin produced in food/GIT 1 Emetic type: e.g fried rice, pasta; large quantity

cooked but cools slowly. Spores germinate in log phase to vegetative form & release toxin.

N & V ,crampsOnset; 1-5 hrs; self limiting, 24 hrs. 2. Diarrheal type: meat dishes & sauces

BACILLUS CEREUS

BACILLUS CEREUS BA

Diarrheal form

• Incubation: 1-24 hrs• Profuse diarrhea, pain, cramps• No fever / vomit2.EYE INFECTION: trauma-associated; FBSevere keratitisEndophthalmitisPanophthalmitisRetinal damage; blindness

Local & Systemic infectionsopportunistic

periodontal diseaseDEVICE ASSOCIATED/ IV DRUGS• Endocarditis• Meningitis• Osteomyelitis• PneumoniaT/M:• R: Pencillin, cephalosporins• Use: Vancomycin, clindamycin alone or Amino-Glyco

OTHER BACILLI

• B THURINGIENSIS• INSECT PATHOGEN/ pesticide role• Produces a crystal toxin• USED AS INSECTICIDE : genetic material

inserted in genetic material of plants• Concern???/

BACILLUS ANTHRAX

• PATHOGENESIS:ZOONOSIS:• Herbivores; goats, sheep, cattle, horses, rats-R

via mouth with spiny vegetation irritating gut-GIT• HUMANS: 3 portals• Cutaneous Anthrax: injured skin• GIT Anthrax: mm; animals; n & v

bloody diarrhea• Inhalation Anthrax: lung

EPIDEMIOLOGY

SOIL: • contaminated from caracasses of dead

animalsSpores viable for decades• Germinate at pH 6.5 & suitable temperatureAnimals: Grazing animals with injured mm

perpetuate chainHUMANS: contact; animals, hides, hair, brushes

ENTRANCE

• Germination of spores• Vegetative form: gelatinous oedema/congestion• Spread: lymphatics…blood…tissues…deathVirulence:• CAPSULE:• Plasmid born Poly-D-Glutamic acid antiphagocytosis

TOXIN

• CONSTITUTED BY 3 PROTEINS• 1.Protective antigen: PA binds receptor to

facilitate entry of 2,3• 2. Edema Factor: EF is adenylyl cyclase 1&2 make oedema toxin• 3. Lethal Factor: LA 1 & 3 make “lethal toxin’…death of host:

plasmid borne: different plasmid

Wool sorter disease• Inhalation anthrax• Incubation: upto 6 weeks• Spores inhaled: wool, hair, hides• LUNGS: phagocytosed…lymph…Mediastinal LNGermination…TOXIN…hagic mediastinitis & necrosis…

oedema..sepsis..git..hagic ulcers; hagic meningitis...fatal.

Hagic pleural effusionCough: tracheal comressionPAIN; substernalX RAY: mediastinal wideningLethal spore dose : >107/ml in blood

PATHOLOGY• Site of entry: proliferate• Capsule: intact• Proteinaceous fluid: surrounds• Few leukocytes• Disseminate rapidlyResistant animals• proliferation takes hours,• WBC accumulate massively• Capsule disintegrates• Organism remains locally

CLINICAL FINDINGS • Cutaneous anthrax: 95%• Inhalation: 5%• Git: rare infected meat associated; Asia, Africa,US• BIOTERRORISM: 2001;22 cases;11 each; 5 diedCUTANEOUS ANTHRAX• Exposed surfaces: Arms, hands, face, neck• Entry of spore: scratch• Pruritic papule in 1-7 days• Papule…vesicle/ small ring vesicles…coalasce…necrotic

ulcer; 1-3 cms• Central black eschar;

ANTHRAX

ANTHRAX

BILATERAL PLEURAL EFFUSION

• OEDEMA: marked: may take weeks to subside• Lymphangitis… Lymphadenopathy• Sytemic signs: fever, malaise, headache ESCHAR: fully developed in 7-10 days• Dries, loosens, separates• Healing; granulation; after weeks• Scar• Complication: Cut anth…sepsis…meningitis…death• ABiotics no role in progress of disease

SPECIMEN

• Local lesion: fluid; blood• Sputum• Blood• Smears; fresh: large Gram + rods• dried; IF technique• BA: grey…white colonies medusa heads (coma

shape outgrowth) may project; ground glass; rough

• Non-hemolytic;

CAPSULE BACILUS anthrax

BACILLUS ANTHRAX COLONYground glass

GRAM STAIN B ANTHRAX

B anthrax; gram stain; spore

MAcFADYEAN STAIN B ANTHRAXcapsule

BACILLUS ANTHRAX BA(non-hemolytic)

INDIA INK PREP. B ANTHRAX CAPSULE

• Non motile (d/d B cereus; swarms in semi fluid)• Guniea pig: killed by intra peritoneal injection• Capsular growth: bicarbonate medium, CO2 5-

7%• Anthrax specific Phage lysis• ELISA: for AB on sera 4 weeks apart for toxin• 4* increase titre or > 1:32 diagnostic value• PCR• Suspicious organism…dispatch to Referral labs

immunity

• ANIMALS: annual vaccination especially in fields with spores

• Broth cultures at 42-52 0 C for several months lost virulence; so can inject in sheep

• Attenuated live strains• Spore suspensions; attenuate; inject by scar• PA filterates• Russia, China; spore vaccine• US , Britain; bacteria-free filterate of cultures

• FDA: approve toxigenic but nonvirulent, noncapsule strain, bacteria-free filterate

• All 3 proteins present• Adsorbed to Aluminium OH• Dose: 2, 4 weeks then 6,12,18 months• Annual boosters• New recombinant PA vaccine + AlOH: under trial• Well tolerated, immunogenic• Department of defense; exposure prone

TREATMENT

• Ciprofloxacin• Pencillin G with Gentamycin/streptomycin• Bioterrorism: potential exposure• Prophylaxis; cipro or doxycycline• 4 weeks with vaccine;3 doses• 8 weeks without

CONTROL

• Burial caracasses: deep lime pits burn

• Autoclave: animal products for decontamination

• PPE: handling infected material• Vaccination: animals; live, attenuated • Humans: occupational hazard