What is anthrax?

2001 -- A letter containing anthrax spores is mailed to NBC one week after the September 11 terrorist attacks on the Pentagon and World Trade Center. It was the first of a number of incidents around the country. In Florida, a man dies after inhaling anthrax at the offices of American Media Inc.

1 What is Anthrax?

Anthrax is blamed for several devastating plagues that killed both humans and livestock. Soon after scientists learned more about it in the late 1800s, it emerged in World War I as a biological weapon.

1 . What is anthrax?

Morphology

-----observation under microscope Culture

------observation of colonies

Morphology-----Observation under microscope

1-1.2um in width 3-5 um in length Gram positive Sporeforming rod Squared ends Endospore: ellipsoidal shaped centrally

Squared ends

MorphologyMorphology-----Observation under microscope-----Observation under microscope

EndosporeEndospore(resistant to staining)(resistant to staining)

Culture ----Observation of colonies

aerobic

Optimal condition: 37 C

PH: 7.2-7.4

Blood plate Common plate Nutrient broth

Observation of colonies Diameter:2-4mm Colour:grayishwhite Rough colony :

irregular, curving outgrowths from the margin.

Colony of anthrax

Observation of colony

•Enhance production of poly -D-glutamyl capsule

Incresed CO2 tension to 5%Incresed CO2 tension to 5%

Mucoid colony type(thick capsule)Mucoid colony type(thick capsule)

Pathogenicity of B.Anthracis Disease

Pathogenicity of B.Anthracis

Poly-D-glutamyl capsulePoly-D-glutamyl capsule important important Anthrax toxinAnthrax toxinPolysaccharide of bacteriumPolysaccharide of bacteriumAntigen of sporeAntigen of spore

Poly-D-glutamyl capsule

All virulent strains of B.Anthracis form this capsule

anti-phagocytosis

capsule

Anthrax Toxin Consist of 3 components : EF(edema factor)

A fragment LF(lethal factor) (toxicity)

PA(protective antigen) B fragment (non-toxicity,binding

receptor)

Anthrax Toxin

There are 3 active combing forms:

EF+PA LF+PA EF+LF+PA

EF+LF inactive

Disease

multiply at the site of the lesion

get into the circulation

systemic pathology

Cutaneous anthrax :Less lethal forms include cutaneous infections, which occur if anthrax spores come in contact with a cut or other opening in the skin

Pulmonary anthrax: If inhaled, anthrax spores can germinate and lead to infection within one to 60 days. This is pulmonary anthrax, which usually causes death.

Gastrointestinal anthrax :Another form of anthrax develops in the intestine of those who eat improperly cooked meat of animals that have been infected with anthrax

Cutaneous Anthrax

Epilogue

Naturally seldom get Anthrax from animals No chance from person to person transmation Treatment : antibiotics eg.penicillin

Anthrax as a biological weapon?

Use your knowledge to conquer the disease ,but not to destroy our life !

制作人员 刘雯敏 高敏 赵世春 李晓川 程超 李艳霞 曹昱琨 姜宁 李鹏 李山峰 聂磊

PA+EF edema EF: inherent adenylate cyclase suceptic EF+PA

PA+LF lethal activity

LF:Zn dependent protease that can include cytokine production in macrophage and lymphocyte

MAPKK mitogen-activated protein kinase

disrupt cellular signal

PA+LF+EF edema,necrosis,lethal

Both the function of PA+EF and PA+LF Others to neutrophil: EF+LF engulfment of bacteria

susceptibility to infection

Skin anthrax

Less lethal forms include cutaneous infections, which occur if anthrax spores come in contact with a cut or other opening in the skin

Pulmonary anthrax

If inhaled, anthrax spores can germinate and lead to infection within one to 60 days. This is pulmonary anthrax, which usually causes death.

肺炭疽胸片

　 intestinal anthrax

Another form of anthrax develops in the intestine of those who eat improperly cooked meat of animals that have been infected with anthrax

1876 -- Robert Koch confirms bacterial origin of anthrax

1880 -- First successful immunization of livestock against anthrax .

1915 -- German agents in the United States believed to have injected horses, mules, and cattle with anthrax on their way to Europe during World War I

1937 -- Japan starts biological warfare program in Manchuria, including tests involving anthrax

1942 -- United Kingdom experiments with anthrax at Gruinard Island off the coast of Scotland. It was only recently decontaminated.

1943 -- United States begins developing anthrax weapons

1945 -- Anthrax outbreak in Iran kills 1 million sheep