Module: Immunology and Disease:
Q: Define pathogenic:
An organism that causes damage to its host.
Q: Define carrier:
A person who shows no symptoms when infected by a disease organism but can pass
the disease to another individual.
Q: Define disease reservoir:
Where a pathogen is normally found; this may be in humans or another animal and
may be a source of infection.
Q: Define endemic:
A disease, which is always present at low levels in an area.
Q: Define epidemic:
The rapid spread of infectious disease to a large number of people within a short
period of time.
Q: Define pandemic:
An epidemic occurring worldwide, or over a very wide area, crossing international
boundaries and usually affecting a large number of people.
Q: Define vaccine:
Uses non-pathogenic forms, products or antigens of microorganism to stimulate an
immune response which confers protection against subsequent infection.
Q: Define antibiotic:
Substances produced by microorganisms which affect the growth of other
microorganisms.
Q: Define vector:
A living organism which transfers a disease from one individual to another.
Q: Define antibiotic resistance:
Where a microorganism, which should be affected by an antibiotic, is no longer
susceptible to it.
Q: Define toxic:
A chemical produced by microorganism which causes damage to its host.
Q: Define antigenic types:
Organisms with the same or very similar antigens on the surface. Such types are sub
groups or strains of a microbial species which may be used to trace infections. They
are usually identified by using antibodies from serum.
Q: Describe cholera as a disease:
, Module: Immunology and Disease:
Cholera is caused by a gram-negative bacterium known as Vibrio cholerae.
Cholera is endemic in parts of the world.
Its toxins affect the gut lining causing water diarrhoea leading to severe dehydration
and frequently death. Water and many ions are not absorbed.
People become infected through contaminated food or water. They become carriers
and, acting as reservoirs of disease, can contaminate other water supplies and
spread the disease.
Cholera can be prevented with good hygiene and sanitation. Better sewage
treatment, water purification, safe food handling and regular hand washing have all
reduced the incidence of cholera.
Treatment includes replacing electrolytes (water and ions) either orally or
intravenously.
The bacteria can be treated with antibiotics.
A vaccine is available, but only provides temporary protection.
Q: Describe Tuberculosis as a disease:
Caused by the bacillus bacterium Mycobacterium tuberculosis. Named for the
tubercles or nodules of dead of dead and damaged cells in the lungs of people who
are infected.
Spreads rapidly by aerosol transmission, especially in crowded conditions such as in
densely populated cities.
The bacteria mainly infect the lungs, so patients develop chest pain and they cough
up phlegm, which often contains blood. The bacteria may infect lymph nodes in the
neck, which swell. People lose their appetite and develop a fever.
TB is treated with a long course of antibiotics, but the bacterium does show some
antibiotic resistance.
To prevent TB, the BCG vaccine is given to babies. The vaccine is made from an
attenuated strain of a related bacterium.
Q: Describe Smallpox as a disease:
Caused by a DNA-containing virus
The virus is inhaled or transmitted in saliva or from other bodies if there is close
contact with an infected person.
It enters small blood vessels in the skin, mouth and throat and is dispersed around
the body. It causes a rash and then fluid-filled blisters, which leave scars in survivors.
Some survivors also suffer blindness and limb deformities.
A successful immunisation program was based on its low rate of antigenic variation/
mutation and the highly immunogenic of its component antigens. This meant that
the vaccine was highly effective.
There was no animal reservoir and people were keen to be immunised because of
the devastating effects.
Q: Describe influenza as a disease:
Q: Define pathogenic:
An organism that causes damage to its host.
Q: Define carrier:
A person who shows no symptoms when infected by a disease organism but can pass
the disease to another individual.
Q: Define disease reservoir:
Where a pathogen is normally found; this may be in humans or another animal and
may be a source of infection.
Q: Define endemic:
A disease, which is always present at low levels in an area.
Q: Define epidemic:
The rapid spread of infectious disease to a large number of people within a short
period of time.
Q: Define pandemic:
An epidemic occurring worldwide, or over a very wide area, crossing international
boundaries and usually affecting a large number of people.
Q: Define vaccine:
Uses non-pathogenic forms, products or antigens of microorganism to stimulate an
immune response which confers protection against subsequent infection.
Q: Define antibiotic:
Substances produced by microorganisms which affect the growth of other
microorganisms.
Q: Define vector:
A living organism which transfers a disease from one individual to another.
Q: Define antibiotic resistance:
Where a microorganism, which should be affected by an antibiotic, is no longer
susceptible to it.
Q: Define toxic:
A chemical produced by microorganism which causes damage to its host.
Q: Define antigenic types:
Organisms with the same or very similar antigens on the surface. Such types are sub
groups or strains of a microbial species which may be used to trace infections. They
are usually identified by using antibodies from serum.
Q: Describe cholera as a disease:
, Module: Immunology and Disease:
Cholera is caused by a gram-negative bacterium known as Vibrio cholerae.
Cholera is endemic in parts of the world.
Its toxins affect the gut lining causing water diarrhoea leading to severe dehydration
and frequently death. Water and many ions are not absorbed.
People become infected through contaminated food or water. They become carriers
and, acting as reservoirs of disease, can contaminate other water supplies and
spread the disease.
Cholera can be prevented with good hygiene and sanitation. Better sewage
treatment, water purification, safe food handling and regular hand washing have all
reduced the incidence of cholera.
Treatment includes replacing electrolytes (water and ions) either orally or
intravenously.
The bacteria can be treated with antibiotics.
A vaccine is available, but only provides temporary protection.
Q: Describe Tuberculosis as a disease:
Caused by the bacillus bacterium Mycobacterium tuberculosis. Named for the
tubercles or nodules of dead of dead and damaged cells in the lungs of people who
are infected.
Spreads rapidly by aerosol transmission, especially in crowded conditions such as in
densely populated cities.
The bacteria mainly infect the lungs, so patients develop chest pain and they cough
up phlegm, which often contains blood. The bacteria may infect lymph nodes in the
neck, which swell. People lose their appetite and develop a fever.
TB is treated with a long course of antibiotics, but the bacterium does show some
antibiotic resistance.
To prevent TB, the BCG vaccine is given to babies. The vaccine is made from an
attenuated strain of a related bacterium.
Q: Describe Smallpox as a disease:
Caused by a DNA-containing virus
The virus is inhaled or transmitted in saliva or from other bodies if there is close
contact with an infected person.
It enters small blood vessels in the skin, mouth and throat and is dispersed around
the body. It causes a rash and then fluid-filled blisters, which leave scars in survivors.
Some survivors also suffer blindness and limb deformities.
A successful immunisation program was based on its low rate of antigenic variation/
mutation and the highly immunogenic of its component antigens. This meant that
the vaccine was highly effective.
There was no animal reservoir and people were keen to be immunised because of
the devastating effects.
Q: Describe influenza as a disease:
