module 13

Disinfection

Killing or inactivating microbes that cause disease.

Sterilization

Destroying all live microbes, spores, and viruses.

Disinfectant

A substance used on inanimate objects and surfaces that is too toxic for use on living tissues.

Antiseptic

A substance that can be used on living body tissues (e.g., wounds).

Autoclaving

A physical sterilization method that uses steam under pressure.

70% alcohol

A chemical disinfectant used as hand sanitizer and skin antiseptic.

Penicillin

The first antibiotic discovered, identified by Alexander Fleming in 1928 and used clinically starting in 1941.

Selective toxicity

The ability of an antimicrobial to harm microbes without harming the host's cells.

Broad-spectrum antibiotic

An antibiotic effective against a wide range of bacteria.

Narrow-spectrum antibiotic

An antibiotic effective against a specific group of bacteria.

Superinfections

Infections that occur when normal gut flora are disrupted, often as a result of broad-spectrum antibiotic use.

Enzymatic Inactivation

A mechanism of antibiotic resistance where bacteria produce enzymes to inactivate the antibiotic.

Plasmids

Circles of DNA that can be transferred between bacterial cells, often carrying resistance genes.

Bacteriophages

Viruses that infect and kill specific bacteria, being explored as an alternative to antibiotics.

Vaccines

Biological agents that stimulate the immune system to provide long-lasting protection against infections.

Antimicrobial action

Refers to the effects of drugs that are either bacteriostatic (inhibiting growth) or bactericidal (killing bacteria).

Therapeutic index (TI)

A measure of the safety of a drug, expressed as the ratio of toxic dose to effective dose.

Antagonistic Effects

When two medications interfere with each other's effects.

Synergistic Effects

When one medication enhances the effect of another medication.

Additive Effects

When two medications have effects that are neither synergistic nor antagonistic.

Resistance to antimicrobials

The ability of certain bacteria to withstand the effects of drugs that are intended to kill them.