- 1 chromosome - Circular DNA - Mono- or polycistronic (messenger RNA can encode for one polypeptide or many polypeptides) - No nucleus - No membrane organelles - 70s ribosomes (30 + 50_ - Binary fission

- 1 chromosome, linear DNA with histones - Monocistronic - Exon and introns - Nucleus - Membrane organelles - Mitosis with cytokinesis

- 2 Layers inner cytoplasm membrane outer thick peptidoglycan layer - No lipid content - No endotoxin (LPS) - No periplasmic space - Vulnerable to lysozyme and penicillin attack

- 3 Layers Inner cytoplasmic layer Thin peptidoglycan layer Outer membrane with lipopolysaccharide (LPS) - High lipid content - Endotoxin (LPS) - Periplasmic space - Porin channel - Resistant to lysozyme and penicillin attack

- Rods short rods are called coccobacilli

- Use glycolysis with oxygen as the final electron acceptor - Have Catalase, Peroxidase and Superoxide dismutase - NEED oxygen to survive

- Use fermentation only - Can tolerate low amounts of oxygen due to Superoxide dismutase

- Use fermentation only - Cannot tolerate any oxygen due to the absence of enzymes

- Involved in the binding and initial interactions between pathogen and host cells. - Can be proteins in cell walls or membranes, or structures such as pili/fimbriae - Antigenic variation can aid in the persistence of infection (evade host response - surface proteins of bacteria can alter in such a way that it is not recognized by the immune system)

7322 B1 Flashcards by Leonardo Garcia

Obligate intracellular organisms

Cannot live outside a living cell

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Prokaryotes

1 chromosome
Circular DNA
Mono- or polycistronic (messenger RNA can encode for one polypeptide or many polypeptides)
No nucleus
No membrane organelles
70s ribosomes (30 + 50_
Binary fission

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Eukaryotes

1 chromosome, linear DNA with histones
Monocistronic
Exon and introns
Nucleus
Membrane organelles
Mitosis with cytokinesis

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Gram (+) Positive

2 Layers
inner cytoplasm membrane
outer thick peptidoglycan layer
No lipid content
No endotoxin (LPS)
No periplasmic space
Vulnerable to lysozyme and penicillin attack

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Gram (-) Negative

3 Layers
Inner cytoplasmic layer
Thin peptidoglycan layer
Outer membrane with lipopolysaccharide (LPS)
High lipid content
Endotoxin (LPS)
Periplasmic space
Porin channel
Resistant to lysozyme and penicillin attack

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Cocci

-Spherical

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Bacilli

Rods

* short rods are called coccobacilli

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Spiral Forms

Comma

- Spiral

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Pleomorphic

-No distinct shape

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Gram (+) positive

3 Cocci?

4 Bacilli?

Cocci
Streptococcus (chains)
Enterococcus (chains)
Staphylococcus (clusters)
Bacilli
Bacillus (spores)
Clostridium (spores)
Corynebacterium (No spores)
Listeria (No Spores)

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Gram (-) negative

2 Cocci?

1 Spiral?

1 Comma?

Cocci
Neisseria (diplococci)
Moraxella (diplococci)
Spiral
Spirochetes (too small to see)
Comma
Vibrio cholerae

REMAINING GRAM NEGATIVE ARE EITHER RODS OR PLEOMORPHIC

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Neither Gram (+) or (-)

Mycobacteria (Acid Fast)

- Mycoplasm (No cell wall)

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Catalase?

Peroxidase?

Superoxide Dismutase?

Catalase - Breaks down hydrogen peroxide to water and oxygen

Peroxidase - Breaks down hydrogen peroxide to water and oxygen

Superoxide Dismutase - Breaks down superoxide radicals

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Obligate Aerobes

Use glycolysis with oxygen as the final electron acceptor
Have Catalase, Peroxidase and Superoxide dismutase
NEED oxygen to survive

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Facultative anaerobes

Aerobic bacteria that can grow in the absence of oxygen
Have catalase and superoxide dismutase
Can use fermentation as a source of energy, as well as glycolysis

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Microaerophilic

Use fermentation only

- Can tolerate low amounts of oxygen due to Superoxide dismutase

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Obligate Anaerobe

Use fermentation only

- Cannot tolerate any oxygen due to the absence of enzymes

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Pathogenicity

refers to the ability of an organism to cause disease

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Virulence

Often used interchangeably with pathogenicity, it refers to the degree of pathology caused by the organism

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Avirulent

does not cause disease

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Virulence factors

a structure, toxin, adhesion, etc… that contributes to the ability of a pathogen to cause disease

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Adhesion factors

Involved in the binding and initial interactions between pathogen and host cells.
Can be proteins in cell walls or membranes, or structures such as pili/fimbriae
Antigenic variation can aid in the persistence of infection (evade host response - surface proteins of bacteria can alter in such a way that it is not recognized by the immune system)

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Multi-layer of endospores

Cell membrane
Thick peptidoglycan layer
Another cell membrane
Wall of keratin-like protein
Outer layer called exosporium

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Facultative intracellular organism

Like to live in the host cell

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Endotoxins

-Part of outer membrane -Part of LPS of Gram (-) bacteria *Listeria monocytogenes, only gram (+) with endotoxin NOTE: Sometimes treating patients with gram-negative infection can worsen disease as bacteria are lysed.

Endotoxins act on...

- Some act outside the host cell (TSST) - Some act on cell membrane - Some act inside the cell

Bacteremia

bacteria in the blood

Sepsis

refers to bacteremia that causes systemic immune response to infection

Septic shock

caused by gram (-) and gram (+) bacteria High mortality (40%) Drop in blood pressure TNF triggers coagulation causing vasodilation

What type of gene transfer are naked DNA fragments are taken up?

Transformation

Two types of Phage dependant gene transfer are?

Generalized and Specialized

What type of gene transfer involves a sex pilus and plasmid?

Conjugation

What are mobile genetic elements that insert into chromosome?

Transposons (Jumping genes)

Naked DNA from a lysed bacterium is picked up by another bacterium

Transformation Recipient bacteria must be competent (able to bind and internalize DNA)

Bacterial Benefits of Capsule

- Both Gram (+) and (-) have them - Interferes with phagocytosis - Impairs complement killing

Defense against Capsules

-Vaccines target capsule -Illicit IgG antibody response which helps macrophage kill bacteria NOTE Some vaccines are comprised of serotypes of capsular polysaccharides

Facultative intracellular organisms often inhibit phagosome-lysosome fusion in macrophages. They also avoid effects of the host cell's release of superoxide and hydrogen peroxide. What are some organisms in this class?

- Listeria monocytogenes - Solmonella typhi - Yersinia - Francisella tularensis - Brucella - Legionella - Mycobacteria - Noardia

Flagella

- Spin and cause the bacteria to move | - Provides strong motility, enables penetration of mucus layer

Pilli (Fimbrae)

- Straight filaments arising from the cell wall - short - Can serve as adherence factors - specialized pili (sex) are involved in gene transfer

What are the two major types of toxins?

Endotoxin Exotoxin

Exotoxins are:

Proteins released by bacteria - Some act on inside the cell * Binding unit (B or H) * translocating unit (A or L) - Some act outside the host cell - Some act on cell membrane

Endotoxins are:

Part of the outer membrane - part of lipopolysaccharide (LPS) of gram (-) bacteria * The lipid A portion of LPS is the toxic component * Sometimes treating patients with antibiotics who have gram (-) infections can worsen the disease as lysed bacteria release large amounts of endotoxin - ONLY GRAM (+) WITH ENDOTOXIN IS * **Listeria monocytogenes***

Bacteremia

bacteria in the blood

Sepsis

refers to bacteremia that causes a systemic immune response to infection

Septic shock

Caused by gram (-) and gram (+) bacteria - Endotoxin (LPS) is often the stimulus of septic shock * Dangerous drop in blood pressure and multi-organ failure * High mortality (about 40%)

Transformation

Naked DNA from lysed bacteria is picked up by another bacteria - recipient bacteria must be competent (able to bind and internalize) - internalized DNA is incorporated into bacterial genome (must have homology)

Associated with burns, diabetic lesions, lungs in CF patients and also Catheters and artificial hips.

BioFilms | -an extracellular polysaccharide network that protects bacteria from antibiotics and immune response.

Streptococci are gram (+) and...

-Found in chains and catalase negative (cannot breakdown hydrogen peroxide to oxygen and water) -Can be classified by their ability to hemolyze RBC and antigenic characteristics of carbs in cell wall *Letter given to different Lancefield antigens

Staphylococci are gram (+) and ...

-Found in clusters (Grapes) and are catalase positive

Lancefield antigen A | -Group A streptococci

Streptococcus Pyogenes - Cause * Strep throat * Scarlet fever * Skin infections * Streptococcal toxic shock syndrome * Streptococcal glomerulonephritis

Non-Lancefield type | Lancet shaped Gram (+) cocci found in pairs (diplococci)

Streptococcus pneumoniae - The major cause of pneumonia and meningitis * otitis media (middle ear infection) in children - The major virulence factor is the polysaccharide capsule * Vaccines are created to target capsule

Group B Streptococci | Streptococcus agalactiae cause...

neonatal meningitis neonatal pneumonia neonatal sepsis sepsis om pregnant

Cause endocarditis (inflammation of the heart), dental infections and abscesses?

Viridans group streptococci

What are the three staphylococci that can cause disease in humans?

aureus epidermidis saprophyticus

Staphylococcus aureus is coagulase ______

positive (can cause blood clot)

Gram positive cocci, chains -catalase negative -how they are classified: =By their ability to hemolyze RBC’s in agar plate =By antigenic characteristics of carbohydrate in cell wall (Lancefield antigens) -Letters given for different Lancefield antigens (A, B, C, D, E, through S) =5 are significant human pathogens. 3 are A, B, and D, while other two do not have Lancefield antigens

Streptococci

Gram-positive, catalase negative -Group A streptococci =Lancefield antigen “A” =Carbohydrate found in cell wall -Virulence factors =M protein – inhibits complement activation and phagocytosis =Antibodies against M protein aids in destroying organism =Streptolysin O and Streptolysin S =O is oxygen labile, S is oxygen stable =Lysis red and white cells, responsible for beta hemolysis -Diseases caused by include: Strep throat, scarlet fever, skin infections, Streptococcal toxic shock syndrome, rheumatic fever, post-streptococcal glomerulonephritis, and others

Streptococci pyogenes

Lancet-shaped gram positive cocci found in pairs (diplococci) -No Lancefield type -Major cause of bacterial pneumonia and meningitis in adults -Otitis media(middle ear infection) in children -Major virulence factor is its polysaccharide capsule =Protects from phagocytosis =Antibody against capsular polysaccharides are protective, Vaccines target these. Unfortunately, many serotypes of capsular antigens (antigenically different), thus vaccines target most common ones.

Streptococcus pneumoniae (also known as pneumococcus)

- Group B streptococci - Neonatal meningitis, neonatal pneumonia, neonatal sepsis - Sepsis in pregnant women

Streptococcus agalactiae

Cause endocarditis, dental infections, and abscesses

Viridans group streptococci

- Fever, myocarditis, migratory arthritis, rash, etc. - Immune responses against M protein can cross react with heart tissue (molecular mimicry) - Can cause permanent damage to heart valves - Strep throat usually treated to prevent this complication, as most people will quickly recover from strep throat without treatment.

Rheumatic fever caused by antibody-mediated complications

- Occurs about 1 wk after pharyngeal or skin infections by nephritogenic strains of beta-hemolytic GAS. - Ab-Ag complexes in circulation deposit in kidneys, result in damage due to complement and PMN. - Generally, does not cause long term kidney damage

Acute post-streptococcal glomerulonephritis caused by antibody-mediated complications

Gram positive cocci, found in clusters like graps | Catalase positive

Staphylococci

-Coagulase positive (causes blood clot) -Member of normal flora of nose and skin in many people problem in hospital =Causes skin infections, pneumonia, osteomyelitis, endocarditis, etc -Has proteins that disable defenses, tunnel through tissues, exotoxins =Lots of virulence factors that contribute to it being a successful pathogen, Examples: ==Coagulase positive (distinguishes from other staphylococcal species) ==Fibrin formation around bacteria, preventing phagocytosis ==Hemolysins that destroy RBC’s, neutrophils and macrophages ==Protein A in cell wall – binds Fc portion of IgG antibody to prevent complement activation ==Toxins **Enterotoxin – heat stable toxin that causes food poisoning (preformed toxin in food) E.g. potato salad and other food **Toxic shock syndrome toxin (TSST-1) – superantigen that causes massive T cell activation with cytokine production, resulting in multiple symptoms including shock

Staphylococcus aureus

Multiple strains that can be found outside of the hospital. Tends to be sensitive to several oral antibiotics, e.g. clindamycin and trimethoprim-sulfamethoxazole

Community-acquired MRSA (CA-MRSA)

Multi-drug resistant, even against methicillin and Naficillin - Vancomycin can be effective - Vancomycin resistant strains (VRSA) are reported

Methicillin-resistant S. aureus (MRSA)

- Coagulase negative - Normal flora of skin - Nosocomial infections, including biofilms associated with prosthetic devices - Resistant to antibiotics

Staphylococcus epidermidis

- Coagulase negative | - Urinary tract infections in sexually active women

Staphyloccus saprophyticus

Are aerobic (likes oxygen) -Only bacteria with capsule composed of protein =Prevents phagocytosis -Anthrax – primarily affects herbivores, but can cause disease in humans =Skin, gastrointestinal and pulmonary forms of disease -Toxin composed of 3 proteins that are non toxic alone, but together produce the effects of anthrax =Edema factor – impairs neutrophil function and causes edema =Protective antigen – promotes entry of edema factor into cells =Lethal factor – stimulates macrophages to release TNF and IL-1, contributing to death -Rapid identification critical in treatment

Bacillus anthracis

Are anaerobic (cannot grow in oxygen) -Pseudomembranous enterocolitis -Gram (+) spore-forming rods -Diarrhea following broad spectrum antibiotics =Antibiotics wipe out normal flora, allowing pathogenic C. difficile to superinfect colon -Toxins =Toxins A and B damages mucosal cells so extensively that they no longer control water movement =Toxin B is more cytotoxic than toxin A. =Strains with new toxin: binary toxin CDT -Treatment for C. difficile =Metronidazole – mild disease =Vancomycin – severe disease =Spores resistant to antibiotics, and therefore relapse can occur (10-25%). *Fidazomicin shown superior to vancomycin in treating recurrences

Clostridium difficile

Are anaerobic (cannot grow in oxygen) -Lethal neurotoxin that causes a rapidly fatal food poisoning -Exotoxin (neurotoxin) blocks the release of acetylcholine in nerve terminals, causing flaccid muscle paralysis. -Spores found in smoked fish, home-canned vegetables =If not cooked thoroughly, and then placed in anaerobic environment. *Spores germinate, and bacteria grow and release toxin

Clostridium botulinum – botulism

Are anaerobic (cannot grow in oxygen) - Spores commonly found in soil, enter skin through trauma - Produces tetanus toxin, causing sustained contraction of skeletal muscles. - “Lockjaw” - Vaccine is against the toxin

Clostridium tetani – tetanus

Are anaerobic (cannot grow in oxygen) - Spores found in soil, contaminates wounds - Deep wounds with dead tissue, anaerobic environment. - Bacteria grows and releases exotoxin enzymes

Clostridium perfringens – gaseous gangrene

Non-spore forming gram positive rods - Causes diphtheria - Pseudomembrane of fibrin, leukocytes, dead epithelial cells and bacteria in pharynx - Exotoxin mediated - Vaccine is against toxin

Corynebacterium diphtheriae

Non-spore forming gram positive rods - Septicemia in pregnant women - Neonatal meningitis and meningitis in immunosuppressed patients

Listeria monocytogenes

-Cause of leprosy, also called Hansen’s Disease -WHO estimates about 2 million people infected with this organisms in the world =Most in India, Brazil, Burma, Indonesia, Madagascar and Nepal =In U.S., over 100 newly diagnosed cases per year. • Usually in immigrants -Impossible to grow this bacteria on artificial media -Clinical manifestations are dependent upon 2 phenomenon: =Severity dependent on host’s cell-mediated immune response • Similar to that described for TB =Bacteria appear to grow better in cooler body temperatures closer to skin surface • Damages skin, superficial nerves, eyes, nose and testes

Mycobacterium leprae

o Smallest free-living organisms capable of self replication o Lack cell wall (no peptidoglycan, etc) o Cannot be gram-stained o Only protective layer is a cell membrane o Lipid bilayer packed with sterols (like cholesterol) o Pleomorphic – many shapes but no defined shape o Antibiotics against cell walls are ineffective, e.g. penicillin, cephalosporin o Two major pathogenic species =Mycoplasma pneumoniae =Ureaplasma urealyticum

Mycoplasmatacea

o Number one cause of pneumonia in teenagers and young adults  More frequent in college dorms and military barracks o Causes atypical pneumoniae (walking pneumonia)  Most often mild bronchitis and pneumonia, but there are cases of fatal pneumonia. • Clinically these patients do not feel very sick o Gradual onset of fever, sore throat, malaise and persistent dry hacking cough  After treatment, many symptoms disappear but the cough may last up to 2 months. o Major virulence factor is P1 adhesion protein  Attaches to respiratory epithelium, causing ciliostasis and damage o Diagnostic tests are available, but most times not used  Patients are treated with broad spectrum antibiotics that treat common causes of disease • Another cause of atypical pneumonia is Chlamydia pneumoniae

Mycoplasma pneumoniae

o Also known as T-strain mycoplasma (T for tiny because of colony size on artificial media) o Produces urease, which metabolizes urea into ammonia and CO2 o Part of normal flora of 60% if healthy women and commonly infects the lower urinary tract, causing urethritis o Neisseria gonorrhoeae and Chlamydia trachomatis are the other 2 bacteria that cause urethritis o Can cause pneumonia in neonates and play a role in infertility

Ureaplasma urealyticum

o Only pathogenic gram-negative cocci o Found in pairs, e.g. diplococci  Each coccus shaped like kidney bean and the pair of cocci stick together with concave surfaces facing each other.

Neisseria

o Causes second most common sexually transmitted disease (STD) o Urethral, rectal, eye, pharyngeal, joint (arthritis) infections o In women, genital tract infections are clinically silent and can progress to pelvic inflammatory disease  Sterility, ectopic pregnancy, etc o Urethral swabs will show gram-negative diplococcus within WBC

Neisseria gonorrhea (Gonococcus

o Pili  Attachment and prevent phagocytosis  Antigenic variation – Complex genes that undergo multiple recombinations, resulting in pili with hypervariable amino acid sequences • Shift in antigenic type protects from existing antibodies o Invasins - invasion into epithelial cells  Outer membrane protein porins (PorA, PorB)  Opa proteins (results in opaque colonies) o Endotoxin (LPS) - promote inflammation. o No capsule

N. gonorrhea: Virulence factors

o Pili (antigenic variation) o LPS • Has a capsule (gonococcus does not) o Inhibits phagocytosis, unless antibody binds to it o Different polysaccharides, at least 13 serogroups  caused by serogroups A, B, C  Vaccines are available

Neisseria meningitidis

o 5% population carry in nasal passages o High risk groups for disease: Infants (6 mo to 2 yr), Army recruits and College freshmen o Spread by respiratory route o Diseases:  Rash consistent with invasive meningococcal infection  Endotoxin release is responsible, causing vascular necrosis, inflammatory reaction in skin  Meningitis (#1 cause) – common form of disease • Often striking infants < 1 year of age  Bacteremia – severe cases could result in septic shock o Diagnosis: Gram stain and culture of blood, spinal fluid or rash o Treatment:  Patient: Penicillin G or Ceftriaxone  Close contacts: Rifampin or ciprofloxin

Meningococcal disease

carbohydrate portion of LPS

O antigen

capsule that covers O antigen

K antigen

subunit of flagella (if positive, motile bacteria)

H antigen

 Enterobacteriacea  Vibrionacea  Pseudomonadaceae  Bacteroidaceae

Enterics

``` o Gram-negative rods o Many produce enterotoxins: all have endotoxin (LPS) o Transmission  Fecal-oral  Migration up the urethra  Colonization of catheters in hospitalized patients o Many acquired antibiotic resistance o Pathogenic species  Escherichia coli  Klebseilla pneumonia  Proteus mirabilis  Shigella dysenteriae  Salmonella typhi  Yersinia enterocolitica ```

• Enterobacteriaceae

 Heat labile toxin (LT) similar to cholera toxin |  Heat stable toxin (ST)

o Enterotoxigenic E. coli (ETEC)

 Shiga-like toxin (verotoxin) – similar action to Shigella toxin  Attach with pili and toxin leads to intestinal epithelial cell death  Bloody (hemorrhagic) diarrhea  E. coli strain O157:H7 is part of this group

o Enterohemorrhagic E. coli (EHEC)

 Invades into epithelial cells, like Shigella |  Bloody diarrhea

o Enteroinvasive E. coli (EIEC)

``` o Pneumonia (commonly in alcoholics or those with underlying lung disease) o Hospital acquired urinary tract infections and sepsis ```

• Klebsiella pneumoniae

o Dysentery – BLOODY diarrhea | o Shiga toxin – kills intestinal epithelial cells

• Shigella dysenteriae

o Fecal-oral transmission o Carrier state – “Typhoid Mary” o Invades cells, including epithelial cells and macrophages o Can survive intracellularly in macrophages/monocytes o Spread to lymph nodes and finally other organs

• Salmonella typhi

Cholera

o Vibrio cholera

Diarrhea due to eating raw seafood

o Vibrio parahaemolyticus

Bloody diarrhea due to zoonotic infection

o Campylobacter jejuni

Peptic ulcers

o Helicobacter pylori

Anaerobic gut bacteria causing infections due to surgical or trauma damage to intestines

o Bacteroides fragilis

• Hospital-acquired gram-negatives o Often arise from endotracheal tubes, foley catheters, i.v. catheters and surgical incisions. o Most common group is the Enterobacteriacae family of gram-negative bacteria

 E. coli, Klebsiella and Enterobacter

o Healthy people are typically resistant to disease due to this organism o Can cause:  Pneumonia, e.g. cystic fibrosis and cancer patients  Osteomyelitis, e.g. diabetic patients, i.v. drug users  Burn-wound infections  Sepsis (high mortality rate)  UTI and pyelonephritis  Endocarditis (common cause of endocarditis, along with S. aureus, with i.v. drug users)

• Pseudomonas aeruginosa

o Can survive on environmental surfaces, increasing chances of transmission o Pneumonia, bacteremia, UTI, burn/wound infections and eye infections  Very common infection in soldiers with wounds o Can be mistaken for Neisseria  Coccobacillus and on solid media can form diplococci  Sometimes could look gram-positive as well o Challenge to treat due to multidrug resistance

• Acinetobacter baumannii

o Small gram-negative rod (coccobacillus)  Cause of sinusitis, otitis media, meningitis, pneumonia mostly in children o Polysaccharide capsule – multiple serotypes  Type b serotype more invasive than others  Anti-capsule antibody confers protection • Maternal antibodies protect baby for first 6 months • Between 6 months to 3-5 years old children are lacking these antibodies (Type b most important) • Vaccine is available

• Haemophilus influenza

o Meningitis  Main cause of meningitis in children (6 months to 3 yrs) until vaccine was introduced  Potentially fatal infection or development of neurologic deficits.  Following inhalation the organism reaches blood stream allowing penetration into brain o Acute epiglottitis o Septic arthritis o Sepsis

• H. influenzae type b Diseases

o Usually limited to upper airways o Increased lymphocytes often seen in these patients o Exotoxins  Pertussis toxin (AB toxin) – activates adenylate cyclase (precise role unknown)  Extracytoplasmic adenylate cyclase – impairs the function of inflammatory cells  Tracheal cytotoxin – destroys ciliated epithelial cells. May be responsible for violent (whooping) cough

• Bordetella pertussis – Whooping cough

o Cause of Pontiac fever and Legionaires’ disease o Aerosolized contaminated water is inhaled  Form biofilms in water towers, air conditioning systems, whirlpools, etc. o Intracellular pathogen  Lives in amoebas in water  Lives inside macrophages by inhibiting phagosome-lysosome fusion

• Legionella pneumophila

o Can only survive by establishing residence inside animal cells o Need host’s ATP as an energy source

Obligate intracellular bacteria o Chlamydia  C. trachomatis – Eye infections, non-gonococcal urethritis, etc  C. pneumoniae – Atypical pneumonia o Rickettsia  Tend to be zoonotic or vector borne, e.g. from animals or insects  Example: R. rickettsia – Rocky mountain spotted fever (Tick borne)

o Tiny gram-negative bacteria that look like corkscrews  Motile with axial filaments winding around organism • Contraction causes spinning motion

• Spirochetes

 Primary stage – Painless chancre (ulcer)  Secondary stage – Rash on palms and soles, painless wart like lesion, almost any organ can be infected  Tertiary stage – can develop over 6-40 years • Slow inflammatory damage to organ tissue, small blood vessels or nerve cells  Latent – secondary syphilis has resolved but relapses can occur  Congenital – Acquired in utero with high mortality rate

o Treponema pallidum – syphilis (STD)

``` Lyme disease (tick-borne) • Rash, neurologic infections, cardiac infection, arthritis ```

Borrelia burgdorferi

7322 B1 Flashcards

(111 cards)