Microbe-Human Interactions: Infection and Disease

These flashcards cover key concepts related to microbe-human interactions, infection, disease, and epidemiology based on the lecture notes provided.

What is the difference between resident and transient microbiota?

Resident microbiota permanently colonize the host, while transient microbiota may be present for days, weeks, or months.

What is microbial antagonism?

Microbial antagonism is competition between normal microbiota and pathogens, helping to protect the host from infections.

What does the term 'holobiont' refer to?

A holobiont refers to a human plus all of its resident microbiota.

Define pathogenicity.

Pathogenicity is the capacity of an organism to produce disease.

What are true pathogens?

True pathogens are capable of causing disease in healthy persons with normal immune defenses.

What is the role of lactobacilli in the human microbiome?

Lactobacilli produce acid, lowering pH in the vagina to prevent yeast infections.

What is the significance of the Human Microbiome Project?

The Human Microbiome Project studies genetic material to identify the microbial profile inside and on humans.

Explain the difference between endotoxins and exotoxins.

Exotoxins are secreted by live bacteria and can cause damage while endotoxins are part of the bacterial cell wall and are released upon cell death.

What factors can weaken host defenses?

Factors include age, genetic defects in immunity, underlying diseases, and stress, which increase susceptibility to infection.

What is Koch's Postulates?

Koch's Postulates are a set of criteria for determining the causative agent of a disease.

Define zoonosis.

Zoonosis is an infection indigenous to animals but naturally transmissible to humans.

What is an asymptomatic carrier?

An asymptomatic carrier is an individual infected but showing no symptoms of the disease.

What is a reservoir in epidemiology?

A reservoir is the primary habitat from which a pathogen originates.

Differentiate between vertical and horizontal transmission of diseases.

Vertical transmission occurs from parent to offspring, while horizontal transmission occurs between individuals, such as through contact.

What is the incubation period?

The incubation period is the time from contact with a pathogen to the appearance of the first symptoms.

What are the stages of clinical infection?

The stages include incubation, prodromal, invasive, and convalescence periods.