Epidemiology and Bacterial Pathogenesis

Flashcards for review of lecture notes on epidemiology, disease transmission, and bacterial pathogenesis.

Epidemic

Sudden increase in disease cases among a specific population.

Endemic

Disease constantly present at predictable levels.

Chronic

Slow-developing and long-lasting disease.

Carrier

Person who harbors pathogen without symptoms.

Reservoir

Natural host/environment where pathogen lives.

Direct transmission

Pathogen spread via close contact or droplets.

Indirect transmission

Pathogen spread via surfaces, fomites, or dried particles.

Fimbriae

Hair-like structures for bacterial attachment.

Adhesins

Molecules for pathogen attachment to host cells.

Capsule

Protective layer preventing phagocytosis and aiding adherence.

Leucocidin

Toxin that kills white blood cells and leads to pus.

Acute stage

Stage where symptoms are most severe.

Convalescence stage

Recovery period after symptoms disappear.

Negative synergy

When normal flora suppress pathogen growth.

Mutualistic relationship

Both organisms benefit.

Commensalistic relationship

One benefits, the other unaffected.

Opportunistic pathogen

Causes disease when immunity is lowered.

Quorum sensing

Bacterial communication based on population density.

Intraspecific communication

Communication among same species.

Interspecific communication

Communication between different species.

Focal infection

Localized infection that may spread.

Systemic infection

Infection spreading throughout the body.

Microglial cells

Phagocytes of brain and spinal cord.

Phagolysosome

Where pathogens are destroyed after phagocytosis.

Adult Botulism

Intoxication (toxin)

Infant Botulism

Infection (bacteria colonize)

Botulism toxin

Prevents neurotransmitter release, causing paralysis.

Antitoxins

Antibodies made in body to neutralize toxins.

Toxoids

Inactivated toxins used for vaccines.

Alcohol and infections

Alcohol paralyzes cilia, increasing respiratory infections.

Exotoxins

Acute stage

Endotoxins

Decline stage

Nosocomial infection

Infection acquired in healthcare setting.

Endotoxin indicates

Pathogen is Gram-negative

Zoonosis

Disease from animals transmissible to humans.

Fomite

Non-living object transmitting pathogen.

Acute disease

Rapid onset, short duration disease.

Crisis stage

Peak of disease symptoms.

Immunocompetence

Ability to produce a normal immune response.

Exotoxin

Secreted toxin damaging host.

Cytotoxin

Toxin that specifically kills cells.

Cytoplasmic inclusions

Dark-staining structures inside cells during infection.