Microbiology Exam 2

Morbidity

State of being dead

Mortality

State of suffering from a disease

Incidence

Number of new disease cases in a given period of time

Prevalence

Number of existing or ongoing disease cases

Sporadic

An illness that occurs at relatively low levels with no discernible pattern or trend, frequently with no geographic focus

Endemic

An illness that is constantly present (often at low levels) in a population

Epidemic

 An illness with a higher-than-expected incidence in a given period within a given population

Pandemic

An epidemic that is worldwide as opposed to regional

Baseline

Reportable Diseases

Diseases that are considered important to the public health

Distinguish between incidence and prevalence of a disease

Prevalence is the number of cases of an ongoing/re-emerging disease.

Incidence is the number of cases in a new/emerging disease

Signs

Objective and measurable indication of a disease

Symptoms

Subjective experience of disease felt by the patient

Asymptomatic

Not exhibiting any symptoms of disease

Symptomatic

Experiences symptoms of a disease

Subclinical

Disease that does not present any signs or symptoms

Acute Disease

Disease of a relatively short duration that develops and progresses in a predictable pattern

Chronic Disease

Any disease that progresses and persists over a long time

Latent Infectious

When infectious pathogen is inactive

Non-Infectious Disease

Disease that doesn’t spread

Nosocomial

Spread of a disease in a medical setting

Non-Communicable Disease

Infection that doesn’t spread person-to-person

Communicable Disease

Infection that spreads person-to-person

R_o

How many people can one person infect

How are signs reported?

Fever

Cough

Blood Pressure

Anemia

Blood Chemistry

Emesis

Anemia

In which the body does not have enough healthy red blood cells

Blood Chemistry

Blood tests that measure amounts of certain chemicals in a sample of blood

Emesis

Action or process of vomiting

How are symptoms reported?

Pain

Fatigue

Nausea

Cramps

Itching/Irritation

Vomiting

Pathogenicity

Ability of a microbial agent to cause disease

Virulence

Degree to which an organism is pathogenic: severity of disease signs and symptoms

Virulence Factor

Product of a pathogen that assists in its ability to cause infection and disease

Adhesin

Capability of microbes to attach to host cells

Exoenzyme

Secreted enzyme that enhances the ability of microorganisms to invade host cells

Toxin

Poison produced by a pathogen

Bacteremia

Bacteria in the blood

Septicemia

Bacteria in blood that is still growing

Viremia

Viruses in the blood

Endotoxin

Toxins released when a pathogen dies or is in their division phase

Exotoxin

Toxins secreted by pathogens

Disease

Damage the infection causes

Exposure

The microbe has made direct contact with our bodies in a way that is useful for the microbe

Portal of Entry

Location where the host cells are in direct contact with the external environment

Examples of Portal of Entry

Eyes, ears, nose, mouth, broken skin, needle, insent bite, anus, urethra, vagina

Exposure doesn’t mean

Infection

Invasion

Occurs once adhesion is successful; it involves the dissemination of a pathogen throughout local tissues or the body.

Infection

Successful multiplication of the pathogen

Local Infection

Confined to a small area of the body

Focal Infection

Localized pathogen can spread to a secondary location

Systemic Infection

Infection becomes disseminated throughout the body

Describe the pathogenesis of Listeria monocytogenes

Invades multiple cell types in the gut (Tricks epithelial cells to thinking it is food)

Uses actin to move around the cell

Grows through barrier (Grows inside cells and ruptures cells)

Uses endotoxins

Characterize the most vulnerable populations to L. monocytogenes infections

Pregnant individuals

Individuals who are 65 years or older

Individuals with a weakened immune system

Broad Spectrum

An antibiotic that targets a wide variety of bacterial pathogens

Narrow Spectrum

An antibiotic that only targets a specific subsets of bacteria

Selective Toxicity

Desirable quality of an antimicrobial drug indicating that it preferentially kills or inhibits the growth of the target microbe while causing minimal or no harm to the host

Natural Antibiotic

An antibiotic that is produced by bacteria and fungi as a defense against bacteria; produced naturally by microorganisms

Semi-Synthetic Antibiotic

Natural antibiotics that are chemically modified to increase the stability and decrease toxicity

2nd- Generation

Semisynthetic modifications of natural penicillins that are resistant to bacterial enzyme beta-lactamase

3rd-Generation

Broad-spectrum antimicrobial agents useful in a variety of clinical situations

4th- Generation

Semisynthetic modifications of natural penicillin that have the advantage of an extended spectrum of activity particularly against gram negative bacteria

Contraindication

When medicine (like antibiotics), procedures or surgeries should not be used because it may be harmful to the person

Bacteriostatic Drugs

Cause reversible inhibition of growth, with bacterial growth restarting after elimination of the drug

Bactericidal Drugs

Kills their target bacteria

Dosage

Amount of medication given during a certain time interval; determined carefully to ensure the optimum therapeutic drug levels are achieved at the infection site without causing significant side effects to the patient

Route of administration

Method used to introduce a drug into the body; Can be administered orally, intramuscular, or intravenous

Β-lactams

Interferes peptidoglycan from linking together; Destroys central structure

Vancomycin

Stop peptidoglycan from linking together; Cell cannot extend cell walls

Nephrotoxicity

Works in the cytosol to stop transport of peptidoglycan subunits across the plasma membrane

Aminoglycosides

Protein synthesis inhibitors interfere with the ribosome’s proofreading ability, leading to faulty proteins that insert into and disrupt the bacterial cytoplasmic membrane

Tetracyclines

Protein synthesis inhibitors that block the association of tRNAs with the ribosome during translation

Chloramphenicol

Protein synthesis inhibitor with broad-spectrum activity that inhibits peptide bond formation

Macrolides

Protein synthesis inhibitors that inhibits peptide bond formation

Lincosamides

Protein synthesis inhibitors that inhibits peptide bond formation

Oxazolidinones

Protein synthesis inhibitors that interfere with formation of the initiation complex for translation and prevent translocation

Polymyxin

Lipophilic polypeptide antibiotics that target the lipopolysaccharide component of gram-negative bacteria; disrupts the integrity of their outer and inner membranes

Lipopeptide

Interacts with the plasma membranes in the gram-positive bacteria

Nitroimidazoles

Antibiotics that inhibit DNA synthesis

Fluoroquinolones

Synthetic antibiotic that inhibits the activity of DNA gyrase, preventing DNA replication

Triazole

Ergosterol biosynthesis inhibitors used to treat several types of systemic yeast infections

Allylamines

Class of antifungal drugs that inhibit ergosterol biosynthesis at an early point in the pathway

Polyenes

Class of antifungal drugs that bind to ergosterol to form membrane pores, disrupting fungal cell membrane integrity

Imidazole

Class of antifungal drugs that inhibit ergosterol biosynthesis

Echinocandins

Class of antifungal drugs that inhibits cell wall synthesis

Naphthoquinone

Class of antiprotozoal drugs that inhibits electron transport in mitochondria

Sulfonamide

Class of antiprotozoal drugs that inhibits folic acid synthesis

Nitroimidazoles

Class of antiprotozoal drugs that inhibits DNA synthesis

Quinolines

Class of antiprotozoal drugs that inhibits heme detoxification

Benzimidazoles

Class of anthelminthic drugs that inhibits microtubule formation, reducing glucose uptake

Avermectins:

Class of anthelminthic drugs that block neuronal transmission, causing paralysis and starvation

Antifungal drugs

1. Target the cell wall

   • Interfere with chitin and glucan

   • Inhibit ergosterol synthesis

2. Interfere with nucleoid synthesis

3. Interfere with folic acid synthesis

4. Interfere with fungal cytochromes

5. Disrupt mitosis  (targeting microtubules)

Anti-protozoan drugs

1.  Targets metabolism

   • Inhibit electron transportation in mitochondria

   • Interfere with folic acid synthesis

   • Damaging oxygen species

   • Inhibit heme detoxification

2. Targets DNA synthesis

   • Inhibit synthesis

Anti-helminthic drugs

1. Targets metabolism

   • Reduces glucose

   • Block neuronal transmission

   • Inhibit ATP production

   • Inhibit RNA synthesis

Antiviral Drugs

1. Targets enzymes

   • Inhibit nucleic acid

   • Inhibit escape of virus

   • inhibit viral uncoating

   • Inhibition of membrane fusion

Antibiotic Resistance

When a microorganisms change their responses to a certain antibiotic

Multi-drug Resistance

When a microorganism is resistant to certain and multiple types of antibiotics

Efflux Pump

How microorganism controls internal environment

Inactivating Enzymes

When an enzyme mutates and no longer binds to the drug

Target Mimicry

When a microorganism produces a decoy and trap the drug away from the real target

Drug Synergy

Using two antibiotics for a more increased effect against infection