1. Which substance do the pathogens attach to in wounds? Clumping factors and the other binding proteins attach the organisms to clots and tissue components and help in colonization
2. Why an abscessed wound might not respond to antibiotic treatment? Microbes inside the abscess are not sensitive to antimicorbial agents because they have ceased to multiply and active multiplication is needed for most antimicrobial agents to act.
In addition the chemical nature of pus interferes with the action of some antibiotics
Antibiotics cannot diffuse through the abscess due to lack of blood vessels.
3. Why are two or more antitubercular medications used together to treat tuberculosis? Used to treat Drug resistant TB
1. Name at least two bacteria which are normal flora of respiratory system, GI, UTI, skin. Staphylococci and streptococci, helicobacter pylori
2. Describe the impact of Bubonic plague of 13th century on the European population. It killed 2/3 of the population
3. Three kinds of plagues: Cholera, smallpox, aids, flu(Spanish flu)
1. Which type of pneumonia is mainly nosocomial infection? Klebsiella pneumonia
2. What feature of the S. pneumonia cell is responsible for its virulence? Virulence factor: presence of capsule, high antigenic variability based on the type of capsule (over 90 different strains)
2. Which type of pneumonia is mainly nosocomial infection?
3. What feature of the S. pneumonia cell is responsible for its virulence?
It has capsules present, which contribute to its wide variety of antigenic variability. it has over 90 different strains)
4. Name at least two bacteria which are normal flora of respiratory system, GI, UTI, skin.
Staphlococcus (pathogen is S aureus).
Streptococcus (pathogen S pnemoniae may be present)
Caused by Mycobacterium tuberculosis (gram + rod) aerobe grows slowly. High content of LIPIDS in cell wall, which make it RESISTANT to drying and disinfectants
Symptoms include chronic fever, weight loss, cough
Virulence factors include: INHalation of airborn bacteria..then releases ENZYME which preventsFUSION of phagosome & lysosome. They leave the phagosome and multiple.
Diagnostic tests: tuberculin tests for detection of infection (then give antibiotics). Also antigen-antibody tests used to test for presence of antibody (determine if you have had been exposed to TB)
Epidemiology: inhalation of airborne organisms, latent infection in ppl (asymptomatic), can reactivate. 10mil in US affected
Drug resistant strains include MDR-TB (resistant to rifampin and isoniazid) and XDR-TB (resistant to 2nd line drugs)
Mycoplasmal (lacks cell wall)
Caused by Mycoplasma pnemoniae – grows slowly (no cell wall)
Symptoms include cough, aching of muscles, headache, fever, fatigue
Virulence factors: cells attach to receptors of RESPITORY epithelium, inhibiting ciliary motion & destruction of cells
Epidemiology: common w/college students and military recruits. Inhalation of infected droplets, mild infection common and spread from there
Caused by Treponema palidum, a non-culturable SPIROCHETE
Virulence factors involves a primary lesion forming after inoculation, then travels thru BLOOD vessel system & is carried throughout body
Symptoms are firm ulcer @ infection site (primary), RASH (secondary) fever, stroke, nervous system damage (tertiary)
Diagnostic tests are blood tests that check for antibody presence, which is thru antigen-antibody testing.
Epidemiology: Can be obtained from sexual contact with infected partner
Caused by Streptococcus pyrogens (gram +)
*Virulence factors include hyarulonic acid capsule and M protein, which INHIBITS phagocytosis, protein G binding to Fc seg. Of IgG. C5a peptidase destroys C5a, inhibiting attraction to phagocytes
Symptoms are SORE throat, hemorrhages, ENLARGED lymph nodes
Diagnostic TESTS include ANTIGENIC difference (different types of strep evoke different ANTIBODY RESPONSES). IMMUNOASSAY: DNA probe analysis. Also antigen/antibody analysis - Type A is strep, so if you check for ANTIGEN A on the throat by using a known antibody
Caused by pneumococcus, Streptococcus pnemoniae (gram +)
Virulence factors include presence of CAPSULES which lead to HIGH antigenic variability
Symptoms include COUGH, Fever, chest pain, rust colored sputum
Epidemiology: High risk with increased alcoholism, narcotic use, lung disease and viral infections
Klebsiella (in gut)
Caused by Klebsiella pnemoniae
Symptoms are CHILLS, fever, cough, chest pain
Virulence factors include aspiration of mucus droplets by throat, destruction of lung tissue
Epidemiology: occurs in very young or old, immunosuppressed individuals and alcoholics. Resistant to antibiotics
12.Describe the bacterial diseases that were discussed in the class?