Chapter 13 Microbe-Human Interactions

These flashcards cover key vocabulary related to microbial and human interactions, highlighting important concepts from the lecture.

Dynamic equilibrium

The state in which the human body exists with microorganisms, involving constant interactions.

Biofilms

Communities of microorganisms that form on various surfaces, influencing colonization in the human body.

Resident microbiota

Microbes that are normally found in the human body, which can provide protective effects and contribute to immune system maturation.

Infection

A condition where pathogenic microbes penetrate host defenses, enter tissues, and multiply.

Pathogen

Microbe acting as an infectious agent that can cause disease.

Invasive microbes

Microbes that can grow in sterile tissues, potentially causing disease.

Microbial antagonism

Beneficial effects where normal flora prevent overgrowth of harmful microbes.

Endogenous infections

Infections that occur when normal flora is introduced to a previously sterile site.

Asymptomatic (subclinical) infections

Infections that do not show noticeable symptoms or signs in the host.

Epidemic occurrence

A widespread outbreak of disease that exceeds expected levels.

Zoonosis

Infections that are naturally transmissible from animals to humans.

Transmission patterns

Ways in which infectious diseases spread, including direct contact and airborne transmission.

Nosocomial infections

Infections acquired in a hospital setting, often due to exposure to drug-resistant microorganisms.

Probiotics

Live microorganisms that are intended to have health benefits when consumed.

Severity of disease

Depends on the virulence of the pathogen and its ability to cause damage.

Incubation period

The time from initial contact with an infectious agent to the appearance of the first symptoms.

Murine Typhus

A disease spread by fleas that live on rats, caused by the bacteria Rickettsia typhi.

Communicable disease

A disease that can be transmitted from one host to another.

Passive carrier

An individual who carries a pathogen without showing symptoms and can spread it to others.

Exotoxin

Toxins secreted by living bacteria into host tissues.

Endotoxin

Toxins not secreted but released upon the death of the bacteria; part of the Gram-negative bacterial cell wall.

Chronic carrier

An individual who harbors a pathogen for a long period and can shed it.

Virulence factor

A characteristic or structure that enhances the ability of a microbe to cause disease.

Host defenses

The body's immune mechanisms that protect against microbial infection.