Unit 2 Intro to Infectious Diseases Flashcards Preview

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Flashcards in Unit 2 Intro to Infectious Diseases Deck (52):
1

How was the bubonic plague transmitted?

Will we ever be free of disease?

Fleas bit rats who bit people too. Can be passed via respiration from human to human

No.

2

When this value is high, the spread of disease is low and vice versa. Defined as a population and how many people are immune to a disease.

Affected nowadays by vaccines.

What is the example of low herd immunity in human history? Another example is?

Herd Immunity

Native Americans and European Diseases (knowingly giving them smallpox, even)

Spanish Flu

3

Do infectious disease still take a heavy toll on human life?

Yes, but it has been lowered via vaccines, antibiotics, sanitation, medical care

Doesn't apply in third world countries or poorer populations in developed countries

4

This is defined as a disturbance in normal functioning of an organism

Disease

5

This type of diseease is caused by a microbe and can be transmitted from host to host

Infectious Disease (Influenza, HIV, hep B, bacteria, fungi)

6

These are infections diseases of animals that can cause disease when transmitted to humans

Examples?

Zoonotic Disease

Rabies, West Nile Fever

7

In developed countries, why is it usually wild animals that give us rabies?

In what animal is West Nile Virus prominent? How do we become infected? Can it be passed on to someone else?

We vaccinate our domesticated animals

Birds. Mosquitos. No.

8

This is a bacterial disease spread by ticks who feed on deer.

Lyme Disease

9

This is a microbe frequently associated with disease production. It must cause harm (disease)

Pathogen

10

This is the mechanism by which a microbe uses to cause a disease state, it could be enzymes or toxins that cause damage to tissues.

Specific signs and symptoms are associated with specific diseases, however many viruses have the same symptoms which complicate diagnosis

Pathogenesis

11

This term refers to the replication of a microbe (sometimes pathogen) in or on its host.

Infection

Our normal flora infects us too. But its a pathogen infection if it causes damage

12

Do all pathogens have the same ability to cause disease?

These pathogens tend to produce disease readily in healthy hosts, usually a virus

When can it occur in bacteria?

No

Primary Pathogen

When they are not out normal flora, like cholera bacteria

13

This type of pathogen generally only cause disease when placed into an unusual site or when the host has a weakened immune system

Opportunistic pathogens

E. coli in the intestines, which can spread to other parts of our body like after appendicitis

Or developing pneumonia after having the flu, (weakened Immune system) or alcoholism

14

This is a measure of the severity of disease a pathogen can produce.

This is the proportion of infected individuals who develop the disease

Virulence

(0 virulence is not a pathogen)

Case-to-infection ratio (CTI)

15

Pathogens can weaken over time or show varying virulence levels due to________

Attenuated strains show INCREASED/DECREASED virulence

Avirulent strains can no longer cause _____

Genetic differences

Decreased (attenuated viruses are useful in vaccines, like chickenpox)

Disease

16

An individual infected with a pathogenic microbe who never exhibits overt signs or symptoms of the disease (asymptomatic) is called a

They can make other people sick

Typhoid Mary is a good example

Carrier

17

Typhoid fever is transported by the _________ route,

Fecal oral route. How people who ate Typhoid Mary's cold prepared foods got sick

18

What must a microbe do to cause disease?

Gain entry to host
Attach to and invade specific cells and/or tissues within the host
Evade host defenses
Obtain nutrients from the host
Exit the host

19

This organism produces IgA protease, an enzyme that destroys IgA antibodies, evading the immune system

Neisseria gonorrhoeae

20

This organism has iron binding proteins to allow pathogen to acquire iron from the host

Alternatively, other organisms can lyse _____ cells

Mycobacterium tuberculosis

Red Blood Cells

21

This virus causes cellular damage by replicating to induce apoptosis of host cells, often motor neurons

Poliovirus

22

As we've mentioned, pathogens can attach via specific protein protein interactions.

Occasionally, more generalized interactions may allow organism to adhere to a host. In this organism, spores adhere to host hydrophobic surfaces, including cells

Rice Blast Fungus

Cuticle (waxy coating on surface of leaves) is hydrophobic and spores stick really well to it

23

This is defined as the group of organisms that a pathogen can infect

An example of spread of pathogen into a new host via mutation lies in the spread of ______ in cats to become _____ in dogs

Host range

FPLV in cats to become CPV in dogs

24

After attachment and invasion, pathogens must still avoid elimination by host defenses

This is defined as what the immune system recognizes on the pathogen

Some microbes employ _________, shifting their surface protein structures

Antigen

Antigenic Variation

25

Trypanosoma brucei gambiense is a protozoan (eukaryotic) cell that is an example of

Antigenic variation

The antigen always changes and the immune system is always behind the change

26

T. Brucei and N. Gonorrhoeae are examples of

Antigenic variation

27

This evasion is used by all herpes viruses, surviving the initial attack by the immune system and residing in cells and occasionally rises up

Latency

28

When chickenpox (a herpes virus) re-emerges from latency its called

Shingles

29

This bacteria is able to grow inside of our cells, including white blood cells, and is therefore called an intercellular colonizer.

Mostly caused by

It can be categorized as a ______, can grow in cold and can grow in body temps

Lysteria monocytogenes

Processed foods

Psychotroph

30

Other methods microbes use to evade host defenses include this one, where bacteria use _______ to digest phage DNA

Phage evasion mechanisms also exist (RE inhibitors, for instance), prevents it from cutting to get to phage DNA

Restriction Endonucleases

31

Different microbial pathogens cause disease in different ways, contributing to their _______

Pathogenesis

32

These are proteins produced and secreted that can have negative effects on host cells (part of pathogenesis) like an enzyme or protease

These toxins are part of the microbial structure itself (never proteins)

Exotoxins (ex: botulism)

Endotoxinsm (like lipid A in gram negatives or some techoic acids in gram positives)

33

Do viruses usually produce toxins? Why or why not?

Is this pathogenesis?

No, their replication induces either cell death or induced cell death via immune responses to reduce the viral spread

Yes just different.

34

This is the term that means the spread of an infectious agent from one host to another (sick person--> sick person).

It may also occur from a pathogen's natural source (reservoir) to a host (environment --> sick person), like tetanus.

Transmission

35

This disease no longer is an issue because the human person was the only reservoir

Smallpox

36

This route of transmission occurs when there is physical contact between infected/susceptible hosts

Direct Contact (STIs, ringworm)

37

This route of transmission occurs when an object carries an agent between an infected and susceptible individual

The object is often an inanimate object, termed a

Indirect Contact (ringworm too, planter's warts, skin infections, respiratory infections)

Fomite

38

This route of infection occurs via coughing and sneezing, or via a respiratory mechanisms.

Can it be both direct and indirect?

Aerosol

Yes

39

This route of transmission occurs via the genitals touching or even indirect contact (rare)

Sexual Transmissions

40

This route of transmission occurs when bacteria of the digestive tract is transmitted to people's food, or via contaminated water

Fecal-Oral

41

This route of transmissions occurs via another species (usually blood sucking insects - mosquitos, fleas, ticks). They release anti-coagulants from saliva into bite to prevent clotting which can cause infection

Vector-borne

42

This type of transmission occurs from a pathogen going between members of a species other than parent to offspring

Horizontal

43

This route of transmission occurs when transmission of a pathogen happens from parent to child (often in utero, during birth, or shortly after birth) like HIV, measles


For HIV there must be a very high viral load in blood of mother

Vertical

44

How could a disease be transmitted shortly after birth from mother to child?

Breastmilk

45

This type of transfer moves from its natural (reservoir ) host to a human.

Humans are often ________ hosts, where the pathogen isn't efficiently transferred from person to person. They often don't replicate well inside humans or the mode of transmission doesn't occur as often (biting in rabies)

Zootonic Transfers

Dead end

46

This is defined as the study of patterns in disease populations

This is defined as the rate of disease in a population

This is defined as the death rate of a disease

Epidemiology

Morbidity Rate

Mortality

47

What is the federal epidemiological body in the U.S.?

What is the global one?

What is their mission

Center for Disease Control (CDC)

World Health Organization (WHO)

Understand infectious disease spread and be better equipped to prevent them

48

This term means the number of new cases appearing in a population during a specific time period. Contributes to morbidity.

rate = number of new cases/number of people in a population

Incidence

Incidence rate

49

This term means the total number of cases in a population at a particular time. Also contributes to morbidity. Correlates with incidence.

Prevalence

50

This pattern of infectious disease is the baseline, is habitually present in the population. Often results in cyclical patterns of increased and decreased incidence.

What is endemic to north american foxes? The incidence rate depends upon the seasons.

For humans it's

Endemic Disease

Rabies

Colds (rhinovirus)

51

This occurs when an incidence or a disease rises significantly above the normal expected value. Localized (Chicago can have one)

Epidemic

52

This occurs when an unexpected cluster of cases in a short time in an even smaller localized population. Can lead to an epidemic (UIC can have one)

Outbreak