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69 Cards in this Set
- Front
- Back
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Mycobacterium Spp.
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Gram positive rods
Lipid-rich thick cell wall Acid-fast Resistant to antibiotics Resistant to environmental factors Cell wall – adjuvant |
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Mycobacterium Spp.
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General Characteristics
Atmospheric – Obligate/strict aerobic Location – Facultative/obligate intracellular Habitat – Carriers, water, sewage, soil Transmission – Inhalation, ingestion, contact |
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Mycobacterium Virulence Factors Surface Virulence Factors
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Mycolic acids
Trehalose dimycolate (cord factor) Lipoarabinomannan (LAM) Sulfolipids |
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TB complex
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Tuberculosis
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M. avium complex
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Avian tuberculosis Swine mycobacteriosis
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M. avium ssp paratuberculosis
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Ruminant Johnes
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M. lepraemurium
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Cat leprosy
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Mycobacterium Spp. – Disease
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TB complex M. bovis
M. tuberculosis Bovine/Ruminants /Swine/Avian/Others |
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Bovine Tuberculosis
Clinical signs |
Weight loss,
Cough, fever, & nodules Occur in a small number of infected animals |
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Bovine Tuberculosis
Diagnosis |
Skin test – tuberculin test
PPD = purified protein derivative INF-γ test Laboratory identification (BSL-3) Acid-fast stain/PCR Culture (special medium) |
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Bovine Tuberculosis
Control/Prevention/Treatment |
Test-and-slaughter
Notify state/federal authorities Control wildlife No vaccine/no treatment |
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Mycobacterium avium Complex (MAC)
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M. avium – ubiquitous, many serovars
Avian tuberculosis – granulomatous lesions in free-range adult birds Swine mycobacteriosis – granulomatous lesions in lymph nodes Bovine exposure – complicates TB/Johne’s diagnosis |
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M. avium subsp. paratuberculsis (MAP) – Johne’s Disease
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MAP = slow growth (4 mo).
Mycobactin J-dependent for growth Neonates and calves – susceptible Long incubation time (2-5 yrs) Clinical signs – weight loss/diarrhea (4 to 7 yrs) Chronic granulomatous lesion in intestine |
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Johne’s Disease – Clinical Signs
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Weight loss
Diarrhea (late) Intestinal Necrosis (late) |
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Johne’s Disease
Transmission/Diagnosis/Prevention |
Fecal-oral route Serology (ELISA)
Fecal culture/PCR Herold’s egg yolk agar (16 wks) Radiometric culture (4 wks) Reduce environmental contamination No vaccine/no treatment |
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Feline Leprosy
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M. lepraemurium
Obligate intracellular – No culture Granulomatous skin lesions Transmitted by rat bite |
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Nontuberculous Mycobacteria
Opportunistic Infections |
M. marinum
M. fortuitum |
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Nontuberculous Mycobacteria
Diagnosis/Treatment |
Clinical signs Acid-fast stain
Laboratory culture (>7 days) Antibiotic treatment: Trimethoprim- sulfa, Doxycycline |
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Mycobacterium spp -zoonosis
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TB complex – Yes
Avium complex – Yes Immunocompromised individuals Fast growers – Yes Immunocompromised individuals MAP – Crone’s disease? |
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Rhodococcus equi
General Characteristics |
Gram positive coccobacilli
Capsule  |
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Rhodococcus equi
General Characteristics |
Atmospheric – Obligate aerobic Location – Facultative intracellular Habitat – Soil saprophytes
Transmission – Inhalation, ingestion, contact |
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Rhodococcus equi
Pathogenesis |
Surface Virulence Factors
Virulence associated protein A (VapA) - Intracellular survival |
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Rhodococcus equi
Diseases |
Foal pneumonia
Coincides with low maternal Ab/low GI flora High dose-exposure Suppurative colitis Swine lymphadenitis Granulomatous lesion Carcass condemnation Opportunistic infections Many Species & Humans |
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Rhodococcus equi
Diagnosis |
Laboratory culture: Trans-tracheal aspirate
Abscess material Treatment Passive immunoprophylaxis Antibiotics: Erythromycin/rifampin |
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Rhodcoccus equi – Zoonosis
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Yes, immunocompromised individual
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Haemophilus felis
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Rhinitis & conjunctivitis in cats
Third most significant organism in conjunctivitis in cats Chlamydophila felis Mycoplasma spp. |
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Haemophilus paragallinarum
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Infectious coryza
Upper respiratory disease of chickens Different serogroups and strains |
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Fowl cholera (Avian cholera)
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P. multocida (capsule type A)
Highly contagious fomites, water, new birds excretions contain bacteria septicemia Swollen wattles, joints, foot pads, Conjunctivitis, respiratory signs |
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P. multocida
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Fowl cholera Highly contagious septicemia
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H. Paragallinarum
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Infectious coryza
Upper respiratory tract infection |
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Taylorella equigenitalis
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Gram and shape
negative rod or coccobacilli (pleomorphic) Habitat Genital tracts of horses Stallions - urethral fossa Mares – clitoral fossa Atmospheric Facultative anaerobic Diseases Contagious equine metritis Transmission During coitus Special REPORTABLE |
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Pasteurella multocida
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5 serogroups
A,B,D,E,F hemagglutination of capsular antigens Eleven (11) somatic serotypes (1-11) Types related to host specificity & pathogenicity (related to disease) |
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Pasteurella multocida
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5 serogroups
A,B,D,E,F hemagglutination of capsular antigens Pasteurella multocida serotypes B:2 (Asia) and E:2 (Africa) Haemorrhagic septicemia Not present in the USA |
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Foreign Animal Disease
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Haemorrhagic septicemia
Pasteurella multocida serotypes B:2 (Asia) and E:2 (Africa) |
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Pasteurella spp
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Virulence factors Capsule
- may facilitate adherence to surfaces - interfere with phagocytosis and protects from complement system attack complexes - different capsular serotypes have different chemical makeup which are similar to that of host tissue - reduces the antigenicity of the capsule fimbria - may facilitate adherence to surfaces - expression of adhesins can be due to environmental cues - different strains may possess different types of fimbriae, each with specificity for a particular receptor lipopolysaccharide (LPS) Endotoxin toxic to respiratory epithelial cells decreases phagocytosis elicits inflammatory reaction |
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Pasteurella multocida
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Virulence factor - exotoxins Pmt (P. multocida toxin)
in P. multocida capsule type D Pmt is osteolytic and induces bone resorption Bacteria inhabits mucous membranes of the upper respiratory tract |
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Atrophic Rhinitis
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P. multocida and Bordetella bronchiseptica
Initial infection with Bordetella bronchiseptica If P. multocida not present, then get a mild, reversible turbinate hypoplasia But, B. bronchiseptica dermonecrotic toxin damages epithelial cells allows P. multocida to adhere www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=pmd &part=A1380&rendertype=figure&id=A1390 Pmt induces destruction and atrophy of nasal turbinate bones |
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Mannheimia spp
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Virulence factors
Leukotoxin (Lkt) LPS Capsule Fimbriae ] together drive a tissue destroying inflammatory response Adh1 (adhesin 1) Fibrinogen-binding proteins Other exotoxins |
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Bovine respiratory disease complex bronchopneumonia
fibrinous pleuropneumonia |
Mannheimia haemolytica Pasteurella multocida
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Bovine respiratory disease complex
Transmission |
inhalation
Ingestion Direct inoculation (bites, scratches, licking) source is carrier or sick animals Endogenous - decreased host defenses allow commensal bacteria living in the upper respiratory tract to infect the lungs |
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Bovine respiratory disease complex
Diagnostics |
Culture
strain typing PCR Samples Nasopharyngeal & tracheal swabs Transtracheal aspirate Bronchoalveolar lavage Lung aspirate Transport media Anaerobic bacteria? |
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Pasteurella and Mannheimia spp
Prevention and control |
elimination of reservoirs of pathogen reduce predisposing factors vaccination - not yet
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Pasteurella and Mannheimia spp
Public health significance |
P. multocida from bite wounds
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Haemophilus
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Gram and shape
negative rod or coccobacilli (pleomorphic) Habitat Commensals of the mucosa of the oropharynx and GI tract Do not survival outside host Atmospheric Facultative anaerobic Diseases H. paragallinarum infectious coryza H. felis Rhinitis & conjunctivitis in cats H. parasuis Glässer's diseases Transmission Shed from nasal cavity Inhalation, direct contact, ingestion of contaminated feed Isolate infected animals virulent to non-virulent strains |
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Haemophilus parasuis
polyserositis (Glässer’s disease) |
septicemia
VERY LITTLE IS KNOWN Virulence factors: Capsules-15 types Gram-negative cell wall LPS and endotoxin Iron acquisition |
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Histophilus somni
(previously Haemophilus somnus) |
along w/ M. haemolytica and P. multocida,
H. somni can be part of the Bovine respiratory disease complex (Bovine shipping fever complex) Thromboembolic Meningoencephalitis (TEME) Disseminated multifocal hemorrhages and infarctions in spinal cord brainstem and cerebral cortex Vasculitis – septic infarction and abscessation Adheres to vascular endothelium – apoptosis and lysis of cells Exposes subendothelial collagen – initiates blood-clotting cascade and thrombosis Histophilus somni – no capsule Gain entrance into circulatory system Septicemia |
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Histophilus somni
Diagnostics |
Culture
Interpretation and sample site location H. parasuis – Normal flora Good sites from freshly deceased pigs or (ideally) acutely ill pigs that are sacrificed. peracute - disease case are lung, joint and brain acute and chronic form - peritoneal fluid, fibrin in the peritoneum, lung and pericardial fluid. Serology Histophilus somni (AGGL) at TVMDL Infectious coryza PCR (Infectious coryza) Specimen requirements: Throat swab or sinus swab. |
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Brucella spp.
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• Member of the family Brucellaceae
• Gram negative coccobacilli – Non‐motile – Increased CO2 – Non‐spore forming • Obligate pathogen – Reproductive tract – Reticuloendothelial system • Atmospheric – Obligate Aerobe • Location – Facultative Intracellular • Environment – Can persist in the environment: – for up to 6 months at 0°C – up to 125 days in dust or soil – up to 1 year in feces • Transmission – Direct contact, Ingestion, Inhalation |
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Brucella spp.
Virulence Factors |
• Surface Virulence Factors
– No capsules, spores, or flagella – Lipopolysaccharide (LPS) – Inhibits phagolysosome fusion • Prevents macrophage apoptosis – Iron Acquisition • Secreted Virulence Factors – Type IV secretion system |
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Brucella spp.
Species Affected |
• Brucellaabortus
– Cattle • Brucellasuis – Bison – Elk – Camels – Yak – Pigs • Cattle • Caribou • Brucellacanis • Brucellamelitensis – Goats – Dogs • Brucellaovis – Sheep – Camels – Alpacas – Llamas – Sheep • Brucellaneotomae – Wood rat (Neotoma lepida) • Brucellacetaceae • Brucellapinnepediae |
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Reservoirs for the Brucella Species
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• Brucellaabortus cattle
• Brucellamelitensis sheep/goat • Brucellasuis pig • Brucellacanis dog • Brucellaovis sheep • Brucella neotomae mouse |
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Brucella
Pathogenesis |
• Enter/invade in the ileal Peyer’s patches
• Ingested • Engulfed by macrophages – Survive in the macrophage • Suppress the myeloperoxidase H2O2 system – Inhibit phagolysosome fusion in neutrophils • Migrate to the lymph nodes where they infect other cells or are killed • From lymph nodes, the Brucella disseminate – Reticuloendothelial system – Reproductive tract • In a pregnant animal, the Brucella infect the placenta and fetus – Erythritol – Localizes to the trophoblasts of the placentome – Spreads to the fetus |
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Brucella
Transmission |
• Major source of infection – Aborted fetus
– Placenta – Post abortion uterine fluids – Sexually transmitted – Milk—calves, kids, humans – Urine—B. canis |
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Brucella
Survival Environment |
• Survive for up to 4 months in milk, urine, water and damp soil.
– Moisture – Temperature—cooler better • Pasteurization effectively kills Brucella sp. |
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Brucellosis Testing
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• Gold Standard—bacterial culture
• Serology – Slide Agglutination • with rivanol • with beta‐mercapthoethanol – AGID (Agar Gel Immunodiffusion) – ELISA – CFT (Complement Fixation Test) – Fluorescence polarization |
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Brucellosis Vaccination
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• B. abortus (cattle) – Strain 19
– RB51 • Cattle – Calves less than 1 year of age – Permanently identified • Ear tattoo • Tamper proof ear tag |
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Brucellosis
Public Health Significance |
• Veterinariansandabattoirworkers
• Labacquiredinfection • Ingestionofunpasteurizeddairyproducts |
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Clinical Signs Human Brucellosis
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• Chronicdebilitatinginfections
– Flu‐like symptoms...but much, much worse • Fever—undulant fever • Night Sweats • Fatigue • Joint Pain (arthralgia and arthritis) • Back Pain (osteomyeleitis and discospondylitis) • Abortion in pregnant women • Headache • Depression • Insomia |
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Brucella
Regulatory Status |
• SELECT AGENT
– USA PATRIOT Act and Public Health Security and Bioterrorism Preparedness and Response Act of 2002 |
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Reportable Infections in Texas
Brucella |
• Brucella abortus in cattle
• Brucella melitensis in sheep and goats • Brucella suis in swine |
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Francisella spp.
Characteristics |
• Gram negative
• Non‐Motile • Non‐spore forming • Siderophores |
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Francisella spp.
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• Atmospheric – Obligate Aerobe
• Location – Facultative Intracellular • Environment – Can persist in the environment: – for up to 6 months at 0°C – up to 125 days in dust or soil – up to 1 year in feces • Transmission – Direct contact, Ingestion, Inhalation |
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Francisella spp.
Virulence Factors |
• Capsule
• Cellwall • Acidphosphatase – Suppresses respiratory burst of phagocytes • TranscriptionalRegulators – Igl—intracellular growth locus • Prevents secretion of proinflammatory cytokines – Mgl—macrophage growth locus • Prevents phagosome‐lysosome fusion • TypeIVSecretionSystem |
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Francisella spp.
Disease Syndrome in Dogs and Cats |
• Infection
– Ingestion of infected animal (rabbit etc) – Tick bite • Susceptibility is somewhat dependent on age – Younger animals are more susceptible • Cats – Older animals may be resistant |
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• Francisella tularensis
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– F. tularensis subsp. tularensis (formerly biotype A)
– F. tularensis subsp. holartica – F. tularensis subsp. novicida – F. tularensis subsp. mediasiatica |
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Reservoir Hosts
• Francisella tularensis |
• Lagomorphs – Rabbits
– Hares • Rats • Mice |
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Vectors
• Francisella tularensis |
Amblyomma americanum
Lone Star Tick Lawnmower Dermacentor variabilis American Dog Tick |
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• Francisella tularensis
Diagnostics |
• Incats
– Leukocytosis – Thrombocytopenia – Increased liver enzymes – Increased bilirubinemia • ELISA • Microscoicagglutination • Fluorescentantibodytechniques • Culture – ONLY performed in laboratories with appropriate biological containment • Biosafety Level 3 |
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• Francisella tularensis
Public Health Significance |
• Human Symptoms of Tularemia:
– sudden fever – chills – headaches – diarrhea – muscle aches – joint pain – dry cough – progressive weakness CDC – People can also develop pneumonia with chest pain, cough, and difficulty breathing. |
