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Coxiella burnetii. By. R.Teja sri. Introduction. Coxiella burnetti is the causative agent of ‘ Q-fever’ Obligate intracellular, gram negative bacterium D istributed globally Found in many species of animals. Morphology:-. obligate intracellular pathogen . gram negative .
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Coxiella burnetii By R.Teja sri
Introduction • Coxiella burnetti is the causative agent of ‘Q-fever’ • Obligate intracellular, gram negative bacterium • Distributed globally • Found in many species of animals
Morphology:- • obligate intracellular pathogen . • gram negative . • Pleomorphic . • size : rods:- 0.2 – 0.4 x 0.4 – 1.0 mc spheres :- 0.3 – 0.4 mc • filterable . • better stained with GIMINEZ and other rickettsiael stains .
C. burnetii i en.wkipedia.org
Culture • Grows well in yolk sac of chick embryos and in various cell cultures .
Ag structure • shows phase variation . • phase – I ,II . • phase – I :- autoagglutinable more immunogenic activity due to periodate sensitive trichloracetic acid-soluble surface carbohydrate . • Phase – II :- more suitable for CFT . • both phase I ,II elicit good Ab response .
Resistance • Resistant to physical and chemical agents • In pasteurization flash method is effective • Can survive in dust and aerosols • Inactivated by 2% formaldehyde 5% H2O2 1% Lysol .
Contd…. • Resistant to heat, drying and disinfectants • Air samples test positive for 2+ weeks • Soil samples test positive for 150+ days • Spore formation
History • Q stands for Query or Queensland • Origin of disease unknown • First reported cases were in Queensland, Australia
Differentiating features : 1. Having smaller size 2. Resistance to heat and drying 3. Major route of transmission is- inhalation/ingestion
Primary Reservoir Goats Cattle Sheep * All eukaryotes can be infected
Bacteria is excreted in: Feces Urine Milk of infected animals
Do not touch! Release Into Environment:- • During birthing the organisms are shed in high numbersin amniotic fluids and the placenta • 109 bacteria per gram of placenta
Transmission • Most common route is inhalation of aerosols • Contaminated dust, manure, birthing products • Tick bites (rare) • Human to human also very rare gsbs.utmb.edu
Contd….. • Who’s at risk? • Farmers, veterinarians, researchers, abattoir (slaughterhouse) workers etc. • People who breed animals • Immunocompromised
Acute or Chronic Q fever gsbs.utmb.edu *Bacteria spread through blood
Symptoms • Acute Q fever • Self-limiting, flu-like disease • Fever, nausea, headaches, vomiting, chest/abdominal pain • Pneumonia & granulomatous hepatitis
Chronic Q fever (> 6 months) • Endocarditis & meningoencephalitis • Pre-existing disease
Host interaction Entry via inhalation Alveolar macrophages encounter bacteria C. burnetii phagocytosed Macrophage C. burnetii R Heinzen, NIAID
Host interaction • Replication within phagolysosme • Low pH needed for metabolism • No cellular damage unless lyses occurs • Can invade deeper tissue and cause complications
Phagocytosis • Binding/entry into macrophages via: • Integrin Associated Protein (IAP) • Leukocyte Response Integrin (LRI) bacteria macrophage
Phagocytosis Phagocytic vesicle Phago-lysosome fusion: bacteria survive and multiplies Lysis of phago-lysosome and macrophage Binding & Entry
LAB DIAGNOSISHard to diagnose because: Asymptomatic in most cases Looks like other disease (Flu or cold) Serology continues to be best method PCR, ELISA and other methods WEIL – FELIX test is negative .
Contd….. • Bio safety level 3 (BSL-3) facility • Very infectious (one organism causes infection) • Listed by the CDC as a potential bioterrorism agent. • Isolated in cell cultures or embryonated eggs
Treatment • Once infected, humans can have life-long immunity • Acute Q fever treated with: doxycycline, chloramphenicol, erythromycin or fluoroquinolones • Chronic Q fever treated with: • More than one antibiotic • tetracycline and cotrimoxazole for 2 years
Vaccines :- • prepared from formalin killed whole cells attenuated strains trichloroacetic acid extracts
Prophylaxis:- • Pasteurization and sterilization of milk and other dairy products • Disinfect utensils, machines used in farm areas for birthing • Regular testing of animals and those who work closely with them • Protective Personal Equipment
INTRODUCTION • Family Bartonellaceae contain two genera Bartonella Grahamella • Grahamella does not infect humans
Bartonella contain 3 species: B.bacilliformis B.quintana B.henselae
BARTONELLA BACILLEFORMIS • Carrions disease • Causes OROYA fever
MORPHOLOGY: Gram negative Pleomorphic strict aerobe motile, small bacillu0.3-0.5x0.2-0.5mc found inside erytrocyte infected persons Opt. temp 25-28 c
CULTURE; Grow in semisolid nutrient agar with 10% rabbit serum 0.5%Hb Growth is slow takes about 10 days
PATHOGENISIS:- • Causes OROYA fever • Transmitted by SAND flies • INCUBATION PERIOD; 3 weeks to 3 months
CLINICAL FEATURES:- • Fever • Headache • Chills • Severe anemia • Several weeks after recovery pt. develop nodular lesions on the body Secondarily infect produce ulcers – VERUGA PERUANA
Lab diagnosis:- • Demonstrated in blood smear by GIEMSA stain • Seen in cytoplasm and adhere to cell surface • Grown on NA agar contain rabbit serum, Hb • Guinea pig inoculation leads to VERUGA PERUANA
TRETMENT:- • Susceptible to penicillin streptomycin Tetracycline Chloramphenicol
PREVENTION • Insecticides such as DDT should be used to eliminate sand flies
MORPHOLOGY:- small gram negative bacillus 0.3-0.5 mc to1.0-1.7 mc Does not posses flagella show twitching movments by fimbriae
CULTURE:- • Grows on rabbit /sheep blood agar • opt. temp -35 c in 5% CO2 • colonies appear after 14 days primary inoculation
PATHOGENESIS:- Formerly called Rochalimaea quintana Causes TRENCH fever also called FIVE DAY fever
Transmission; by body louse • vertical transmission does not occur in lice • Lice after acquiring infection remain infectious through out life
CLINICAL FEATURES:- • Mild symptoms • leads to chronic rickttesiaemia • Relapse have been observed even after 20 years primary disease
Lab diagnosis:- • Detected in the gut of infected lice • Isolate from pt. blood by cultur sheep blood agar • Weil-felix test negative • PCR- detect organism in tissues
MORPHOLOGY:- Gram negative Slightly curved Show twitching movments