this presentation is about the causal organism, symptoms, infection, prevention and treatment of the disease caused by bacillus anthracis. this presentation is for medical microbiology student to help in their understanding about the subject.
2. HISTORY
• 700 B.C. – thought to be originated from Egypt and
Mesopotamia
• 1887 – ROBERT KOCH proved anthrax bacterium was cause of
disease that affected farm animals
• 1881 – LOUIS PATEUR created 1st vaccine and tested on farm
animals
• 1950’s – first anthrax vaccine for human was developed
• 2001 – bioterror attack on U.S. using bacterium spores
• 2016 – 2000 reindeers died and 13 people became sick in
Siberia, Russia
3. CAUSAL ORGANISM
• BACILLUS ANTHRACIS
• Bacteria(domain); Firmicules(phylum); bacilli(class);
bacillales(order); bacillaceae(family); bacillus(genus);
anthracis(species)
• Gram +ve, rod shaped bacterium, non motile, aerobic or
facultative anaerobe
• Genome is circular with 5,227,293 bp DNA molecule
• Cell wall contain peptidoglycan layer, lipoteichoic acids
and crystalline cell surface protein
• CAPSULE is made of poly-D-glutamic acid unlike other
bacteria which have polysaccharide capsules
4. TYPES OF ANTHRAX
Cutaneous
anthrax
• More common
• Mortality rate is low (approx. 20%)
Pulmonary
anthrax
• Very rare
• Mortality rate is very high (around 100%)
• Also known as wool sorter’s disease
Gastrointestinal
anthrax
• Incubation period is 1-7 days
• With treatment, 60% patients survive
5. PULMONARY ANTHRAXINFECTION
• These bacterial spores
can be dormant and
perennate for many years.
• Spore present in air or on
animals when inhaled
causes pulmonary
infection in our lungs
SYMPTOMS
• Sore throat, headache,
shortness of breath
• Pain in chest, coughing up
blood, necrosis
• Progressive haemorrhage
lymphadenitis
• shock, coma
6. CUTANEOUS ANTHRAXINFECTION
• Using bacterial spores
present in soil, air and on
animal fur
• Spores when come in
contact with skin or
wound, germinate to
infect.
SYMPTOMS
• Painless, dark, swelled
pustules
• Septicemia
• Muscle pain, headache,
fever, nausea and vomiting
• Swollen glands and lymph
nodes
7. GASTROINTESTINAL ANTHRAX
INFECTION
• By eating undercooked
contaminated meat
• Bacteria invade through
bowel walls and spreads
through bloodstream
SYMPTOMS
• Nausea
• loss of appetite
• Fever
• Abdominal pain
• Bloody diarrhea
8. PATHOGENESIS
• Helps to elude host’s immune system
• Made of poly-D-glutamic acid
• Acts as anti-phagocytic layers
BACTERIAL CAPSULE
• Helps in destruction of host cell
• Three types- edema factor(EF), lethal
factor(LF), protective antigen(PA)EXOTOXINS
9. EDEMA FACTOR
• Calmodulin dependent adenylate cyclase
• Utilizes ATP
• Causes elevation of intracellular cAMP
• Leads to production of massive amount of fluid causing inflammation
LETHAL FACTOR
• Decrease level of mitogen activated protein kinases
• Causes tissue necrosis and hypoxia
PROTECTIVE ANTIGEN
• Secreted in inactive form; activated by furin
• Facilitates the entry of edema factor and lethal factor inside cell
10.
11. DIAGNOSIS
1. Bacillus anthracis can be cultured in BLOOD AGAR medium
2. Bacteria may be found in
Cultures or smears in case of cutaneous anthrax
Throat swabs or sputum in case of pulmonary anthrax
3. Chest X-rays may shows changes in lymph nodes of lungs
4. Bacteria can be seen in blood using microscope once
anthrax is disseminated
5. History like occupation of person is important
12. PREVENTIONS
• Public health measures to prevent contact with infected animals
• Vaccine available for people at high risks
• Avoid contaminated meat consumptions
• Agencies working hard to prevent bioterrorist attack
14. VACCINATION
• Vaccine for anthrax in animals are available
• It is produced using protective antigen which is a type
of exotoxin
• Vaccine for humans are not yet available for general
public
• All current vaccine show local and general
reactogenicity(erythema, fever, soreness)
• New third generation vaccines are under research
including recombinant live vaccine
