Microbiology Quiz: Infectious Diseases

Statements Not True About E. coli

• E. coli can cause disease.
• E. coli often exists in a mutual relationship with humans.
• E. coli gets nutrients from intestinal contents.
• E. coli provides vitamin K for its host.

Invasion/Colonization

• Invasion or colonization of the body by pathogenic microorganisms is called infection.

Hospital-Acquired Infections

• A nosocomial infection is acquired in a hospital.

Non-Communicable Infections

• Examples include tetanus, leprosy.

Emergence of New Infectious Diseases

• The emergence of new infectious diseases is likely due to factors like human travel, population growth, and environmental changes, but not the need for bacteria to cause disease.

Koch's Postulates

• The pathogen must be present in every case of disease.
• The pathogen must be isolated in pure culture from an experimentally infected animal.
• The disease must be transmitted from a diseased animal to a healthy, susceptible animal by some form of contact.
• The pathogen from the pure culture must cause the disease when inoculated into a healthy, susceptible animal.

Bubonic Plague Incubation Period

• The incubation period for this case of bubonic plague was from September 3rd to 5th.

Prodromal Period for Bubonic Plague

• The prodromal period for this case of bubonic plague was from September 6th to 7th.

Vibrio Cholerae and Plesiomonas Shigelloides Infection Example

• A Maryland woman was hospitalized with dehydration, and Vibrio cholerae and Plesiomonas shigelloides were isolated from her.
• She had neither traveled outside the US nor eaten raw shellfish.
• She had attended a party two days before hospitalization.
• Two other people at the party had acute diarrheal illness.
• Everyone at the party ate crabs and rice pudding with coconut milk.
• Crabs left over from the party were served at a second party; one person at the second party experienced mild diarrhea.
• Specimens from 14 of the people at the second party were negative for vibriocidal antibodies.

Disease Transmission

• The etiologic agent of the disease is Vibrio cholerae.
• The source of the disease was crabs.

Transient Microbiota

• Transient microbiota are present for a relatively short time.

Objective Changes

• Objective changes physicians observe and measure are called signs.

Characteristics of a Disease

• Characteristics can be grouped into syndromes, symptoms, and signs.

Types of Disease Acquisition

• A disease acquired by many people in a given area in a short time is called an epidemic.

Types of Disease Transmission

• The spread of disease agents via contaminated water is an example of vehicle transmission.

Science of Disease Transmission in Populations

• The science that studies when and where diseases occur and how they are transmitted is called epidemiology.

Pathogen Entry Through Skin

• Most pathogens that gain access to the skin must adhere to the surface to penetrate.
• They may potentially invade intact skin via hair follicles or sweat ducts.

Entry Through the Parenteral Route

• All sources of entry via the parenteral route are listed, but hair follicles is not.

Foodborne Botulism Prevention

• Prevent botulism by boiling food prior to consumption.

Virulence Factors

• Virulence of a pathogen is contributed to by factors such as numbers of microorganisms gaining access, evasion of host defenses, and toxin production.

Smallpox Vaccine

• Early smallpox vaccines used infected tissue rubbed onto the skin.
• The recipients usually developed a mild case, recovered, and gained immunity afterwards.

Pathogen and Transmission

• Smallpox is a virus, and skin is the wrong portal of entry.
• A successful pathogen doesn't always kill its host before transmission.

Types of Infectious Diseases

• Infectious diseases might be sporadic, endemic, epidemic, or pandemic.

Infectious agents and immune system

• Pathogens lacking enzyme collagenase are less likely to cause disease.

Highly Virulent Organisms

• Highly virulent organisms are more likely to cause disease.

Disease Classifications

• Botulism is a sporadic disease.
• Measles is a highly contagious disease, as it spreads easily among susceptible populations.
• Endemic diseases are constantly present in a geographic area.

Nonspecific Immune System

• The innate nonspecific immune system uses a general defense mechanism to defend against pathogens.

Shed Cells and Microorganisms

• The outer, thinner layer of cells, frequently sheds dead cells along with microbes, this layer is in direct contact with the surrounding environment.

Chemical Mediators on Skin

• Sebum is a chemical mediator secreted onto the skin that inhibits the growth of certain pathogenic bacteria and fungi.

Leukocytes

• Leukocytes are also called white blood cells and are a category of cells that play a crucial role in the body's defense mechanisms (immunity).

Types of Immunity

• Naturally acquired passive immunity occurs when antibodies are transferred to a susceptible individual through exposure to an antigen.
• Artificially acquired passive immunity occurs when antibodies are deliberately injected into a susceptible individual.
• Naturally acquired active immunity occurs when an individual is exposed to a pathogen.
• Artificially acquired active immunity occurs when a person receives vaccines.

Antigenic definition

• An antigen is something foreign in the body that elicits an antibody response and can combine with antibodies.

Types of Vaccines

• Attenuated whole-agent vaccines use weakened microorganisms or viruses to stimulate an immune response, generally offering lifelong immunity.

Penicillin Discovery

• The individual who first identified penicillin was Alexander Fleming.

Drug Resistance and Antimicrobial Agents

• Microbial resistance to antibiotics develops when antibiotics are indiscriminately used or taken after symptoms disappear.
• Drug resistance can be overcome by using multiple antimicrobial drugs in synergy.

Types of Pathogens and Microbial Agents

• Fungi are a type of pathogen targeted by antifungal agents.

Combining Antibiotics

• Using two antibiotics together isn't always an improvement because they can cause drug resistance or toxicity.

True or False Statements About Immunity

Review the statement, determine if it's true or false, and note why.