Immunity and vaccinations Flashcards
What is active immunity?
This is the type of immunity you get when YOUR IMMUNE SYSTEM MAKES ITS OWN ANTIBODIES after being STIMULATED BY an antigen.
There are two different types of active immunity: Natural immunity. What is natural immunity?
Natural -this is when you become immune after CATCHING A DISEASE. E.g if you have measles as a child, you shouldn’t be able to catch it again later in life
There are two different types of active immunity: Artificial immunity
This is when you become immune after you’ve been given a vaccination containing a harmless dose of antigen.
What is passive immunity?
This is the type of immunity you get from being GIVEN ANTIBODIES MADE BY A DIFFERENT ORGANISM - your immune system does not produce any antibodies of its own.
What is natural passive immunity?
This is when a BABY becomes immune due to the antibodies it receives from its mother, through the PLACENTA and in BREAST MILK.
What is artificial immunity?
This is when you become immune after being injected with antibodies from someone else.E.G If you contract Tetanus you can be injected with antibodies against the Tetanus toxin, collected from blood donations.
Similarities and differences between active and passive immunity.
Active immunity: Requires exposure to antigen
Passive immunity: No exposure to antigen
Active immunity: It takes a while for protection to develop
Passive immunity: Protection is immediate
Active immunity: Protection is long term
Passive immunity: Protection is short term
Active immunity: Memory cells are produced
Passive immunity: Memory cells aren’t produced
AUTOIMMUNE DISEASES involve an …..
Abnormal immune response
Sometimes, an organism’s immune system ISN’T ABLE to ……
RECOGNISE SELF ANTIGENS the antigens present on the organism’s OWN CELLS.
When an autoimmune disease happens, the immune system treats the self-antigens as …
FOREIGN ANTIGENS and launches an IMMUNE RESPONSE against the organism OWN TISSUES.
A disease resulting from this abnormal immune response is known as an …
AUTOIMMUNE RESPONSE
Examples of autoimmune diseases: Lupus, what is Lupus?
Lupus-caused by the immune system attacking cells in the CONNECTIVE TISSUES.
This DAMAGES the tissues and causes painful INFLAMMATION.
Lupus can affect the SKIN and JOINTS, as well as ORGANS such as the HEART and LUNGS.
Example of autoimmune disease: Rheumatoid arthritis. What is Rheumatoid arthritis?
Caused by the immune system attacking cells in the JOINTS. Again this causes PAIN and INFLAMMATION.
Vaccines help to CONTROL DISEASE and …..
PREVENT EPIDEMICS
How can a vaccination help prevent you from suffering from a disease?
While your B lymphocytes are busy DIVIDING to build up their numbers to deal with a pathogen (i.e the PRIMARY RESPONSE), you SUFFER from the disease. VACCINATION can help avoid this.
How do vaccines help the body become immune to a specific pathogen?
Vaccines CONTAIN ANTIGENS that causes your body to PRODUCE MEMORY CELLS against a particular pathogen, WITHOUT the pathogen CAUSING DISEASE.
This means you become IMMUNE without getting any SYMPTOMS.
What is HERD IMMUNITY?
If most people in a COMMUNITY are VACCINATED, the disease becomes extremely RARE.
This means that even people who haven’t been vaccinated are UNLIKELY to get the disease because there is no one to catch it from.
This is called HERD IMMUNITY. It helps to PREVENT EPIDEMICS-MASS OUTBREAKS of DISEASE.
Do vaccines always contain antigens, such as?
Vaccines always contain antigens- these may be FREE or attached to a DEAD or ATTENUATED (weekend) PATHOGEN.
What are boosters?
Sometimes BOOSTER vaccines are given later on (e.g. after several years) to MAKE SURE memory cells are produced.
What is the difference between Vaccination and Immunisation?
Vaccination is NOT THE SAME as IMMUNISATION. Vaccination is the ADMINISTRATION of ANTIGENS (in a vaccine) into the body.
IMMUNISATION is the process by which you DEVELOP IMMUNITY.
Vaccination causes Immunisation.
Routine vaccines are offered to everybody. They include MMR.
The MMR-protects against MEASLES, MUMPS, and RUBELLA. The MMR is usually given to CHILDREN as an INJECTION at around a year old, and again before they start school.
It contains ATTENUATED MEASLES, MUMPS, and RUBELLA VIRUSES.
Routine vaccines are offered to everybody. They include Meningitis C Vaccine.
The Meningitis C vaccine-protects against the BACTERIA that causes MENINGITIS C.
It is first given as an INJECTION to babies at 3 MONTHS.
BOOSTERS are then given to 1-YEAR-OLDS and TEENAGERS.
Vaccines and Vaccination Programmes change-Example: …
Influenza vaccine
Why do the influenza (flu) Vaccine change every year?
The INFLUENZA (FLU) VACCINE changes every year.
That’s because the ANTIGENS on the surface of the influenza virus CHANGES REGULARLY, forming new strains of the virus.
Why can’t memory cells recognise the influenza flu the following year despite having stored the antigen from a vaccine?
MEMORY CELLS produced from VACCINATION with ONE STRAIN of the flu will NOT RECOGNISE other strains with DIFFERENT ANTIGENS.
The strains are IMMUNOLOGICALLY DISTINCT.
Why does the influenza virus need to be modified each year?
Every year there are DIFFERENT STRAINS of the influenza virus CIRCULATING in the population, so a different vaccine has to be made.
Why do laboratories collect samples of different strains of the virus?
LABORATORIES collect SAMPLES of these different strains, and organisations, such as the WHO(world health organisation) and CDC (Centre of disease control), TEST the EFFECTIVENESS of different influenza VACCINES against them.
How is a vaccine selected?
NEW VACCINES are DEVELOPED and one is chosen EVERY YEAR that is the MOST EFFECTIVE against RECENTLY circulating influenza viruses.
How are Vaccines given in a country?
Governments and health authorities then implement a PROGRAMME of VACCINATION using the most SUITABLE vaccine.
Sometimes people are given a vaccine that protects them from a strain causing an epidemic in another COUNTRY-this helps to stop the strain spreading GLOBALLY.
What is the difference between active and passive immunity?
Active immunity: This is the type of immunity you get when YOUR IMMUNE SYSTEM MAKES ITS OWN ANTIBODIES, after being STIMULATED by an ANTIGEN.
Passive immunity: This is the immunity you get from being GIVEN ANTIBODIES MADE BY A DIFFERENT ORGANISM-Your immense system DOESN’T produce antibodies of its own.
What are autoimmune diseases? Give an example.
Sometimes, an organisms’ own immune system doesn’t RECOGNISE SELF ANTIGENS- The antigens present on the organisms own cells.
When this happens, the immune system treats the self-antigens as FOREIGN ANTIGENS and launches an IMMUNE RESPONSE against the organism’s OWN TISSUES.
A disease resulting from this abnormal immune response is known as an AUTOIMMUNE DISEASE.
Examples include LUPUS and RHEUMATOID ARTHRITIS.
Explain how vaccines help prevent epidemics?
If most people in a COMMUNITY are VACCINATED, the disease becomes extremely RARE. This means that even people who haven’t been vaccinated are UNLIKELY to get the disease because there’s no one to catch it from. This is called HERD IMMUNITY. It helps to PREVENT EPIDEMICS -MASS OUTBREAKS of DISEASE.
Influenza is caused by a virus that constantly changes the antigens.
Explain why a new influenza vaccine is made every year.
Memory cells produced from vaccination with one strain of the influenza virus will not recognise other strains with different antigens.
So a new vaccine is made every year to protect against the most recently circulating strains of influenza virus.
