Definations

Question 1

Infection

Answer 1

This is the colonisation step of a host by the pathogenic organism but does not
necessarily imply that the host shows symptoms.

Question 2

Pathogenic organism

Answer 2

This includes microbes and biologically active units, that under certain conditions can infect a higher organism and cause disease. This includes, from smallest to largest: Prions, Viruses, Bacteria, Protozoa/Mold, Worms and arthropods.

Question 3

Disease

Answer 3

This is the infection with subsequent symptoms.

Question 4

Asymptotic Carrier

Answer 4

This describes a reservoir of a pathogenic organisms, meaning you carry
the organism (transport) without showing symptoms.

Question 5

Spectrum of infection

Answer 5

This describes the sum of species that a pathogenic organism can
infect, in which we distinguish between narrow and broad spectrum of infection.

Question 6

Infectious dose

Answer 6

This describes the minimal number of microbes that are required for causing
an infection in the host.

Question 7

Bacteremia

Answer 7

This describes the presence of pathogens in the blood stream. As a side note, the
blood is generally supposed to be sterile.

Question 8

Sepsis

Answer 8

This follows bacteremia where the pathogens can multiply in the blood. This is generally very bad as it is often closely followed by death.

Question 9

Pathogenicity

Answer 9

This describes the ability of a whole species to cause infection or disease.

Question 10

Virulence

Answer 10

More differentiated, this describes the degree of pathogenicity but strain-specific. Every strain has individual properties that additionally can be host-dependant.

Question 11

Lethal Dose 50

Answer 11

This is the number of pathogens required, to kill 50% of an experimental group of hosts.

Question 12

Infectious Dose 50

Answer 12

This is the number of pathogens required to infect 50% of an experimental group of hosts

Question 13

Epidemiology

Answer 13

is the science that is concerned with distribution and prevalence of communicable diseases in population. Nowadays even more relevant than ever, due to easy world travel that offers many transmission opportunities.

Question 14

Epidemic disease

Answer 14

This is a disease that occurs in an unusually high number of individuals in a single population at the same time.

Question 15

Pandemic disease

Answer 15

This is used when an epidemic occurs worldwide.

Question 16

Opportunistic pathogen

Answer 16

do not cause disease in normal habitat in healthy person

Question 17

Incidence of Disease

Answer 17

number of people developing disease during particular time period

Question 18

Prevalence of Disease

Answer 18

number of people suffering from disease during given time period (no matter when they first developed symptoms)

Question 19

Acute disease

Answer 19

rapid development, usually short duration (e.g. influenza)

Question 20

Chronic disase

Answer 20

slow development, may continue for long time (e.g. tuberculosis, leprosy, hepatitis B)

Question 21

Latent disease

Answer 21

causative agent remains inactive for some time but may become active any time and cause symptoms (e.g. shingles caused by varicella virus)

Question 22

Local infection

Answer 22

small area in body invaded by pathogens (e.g. pimples by Staphylococcus aureus)

Question 23

Systemic infection

Answer 23

pathogens and their products spread throughout body by blood or lymph (e.g. measles)

Question 24

Focal infection

Answer 24

pathogen from local infection enter blood or lymph and spread to other, confined body parts (e.g. endocarditis by oral streptococci)

Question 25

Septicemia

Answer 25

pathogens able to multiply in blood

Question 26

Sepsis

Answer 26

toxic inflammatory condition by spread of pathogens or their toxic products

Question 27

Primary infection

Answer 27

acute infection with symptoms

Question 28

Secondary infection

Answer 28

caused by opportunistic pathogen after primary infection