Koch's Postulates, Disease Definitions, and Pathogen Types

What is the first postulate of Koch's Postulates?

• Suspected germ present in all cases

• Germ must be isolated and grown in pure culture

• Germ must cause disease when introduced into a healthy host

• Germ must be re-isolated from the diseased experimental host

Which of the following is NOT a limitation to Koch's Postulates?

• A) Pathogens can be found in healthy host

• B) Some pathogens can't be cultured in lab

• C) All diseases are caused by a single pathogen

• D) Disease can be caused by more than 1 pathogen

Infection is defined as the ________ of the host by a pathogen.

• invasion

• elimination

• protection

• vaccination

What is the difference between symptoms and signs in the context of disease?

• Symptoms are subjective characteristics of disease felt by the patient, while signs are objective manifestations of disease that can be observed or measured by others.

• Symptoms are always visible, while signs are always hidden.

• Symptoms are measured by doctors, while signs are only described by patients.

• Symptoms and signs are both subjective experiences of the patient.

Which stage of disease is described as 'initial exposure to pathogens/onset of noticeable symptoms'?

• Incubation

• Convalescence

• Prodromal

• Acute

The prodromal stage of disease is characterized by severe symptoms and peak pathogen replication.

• True

• False

What is a primary pathogen?

• A primary pathogen causes disease in the host regardless of host resident microbiota/immune system.

• A primary pathogen only infects immunocompromised hosts.

• A primary pathogen is a harmless microorganism.

• A primary pathogen only exists in laboratory conditions.

Surface body colonizers normally ______ cause disease.

• do not

• always

• frequently

• inevitably

Resident microbiota ________ live on humans and help maintain health.

• consistently

• rarely

• temporarily

• occasionally

Tags

NGSS.HS-LS2-6

Transient microbiota are ________ bacteria picked up from surfaces.

• temporary

• permanent

• harmful

• beneficial