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B3 F) Vaccination/ Immunisation
B3 F) Vaccination/ Immunisation
The process of an individual becoming immune to a disease is known as immunisation. We can artificially immunise people by giving them a vaccine. There are many different types of vaccinations, but they usually involve injecting an inactive or weakened pathogen into the body. The inactive or weakened pathogen will cause little damage, but it will result in the B-lymphocytes producing an immune response. This immune response happens because the weakened or inactive pathogen will contain antigens on the surface of their cells. The B-lymphocytes will recognise that the antigens on the surface of the pathogen that has been injected via the vaccine are foreign (not produced by the individual), which will result in the B-lymphocytes producing antibodies to deal with the pathogen. The B-lymphocytes will then become memory B-lymphocytes for the pathogen that the vaccine was for.
The memory B-lymphocytes are useful because when an individual becomes infected with the actual pathogen, the body will produce a secondary immune response. The secondary immune response produces antibodies quicker than the primary immune response, which reduces the chances of an individual being seriously affected by the pathogen. The levels of antibodies in blood from the primary and secondary immune response are shown on the graph below.
The memory B-lymphocytes are useful because when an individual becomes infected with the actual pathogen, the body will produce a secondary immune response. The secondary immune response produces antibodies quicker than the primary immune response, which reduces the chances of an individual being seriously affected by the pathogen. The levels of antibodies in blood from the primary and secondary immune response are shown on the graph below.
From the above graph, we can see that the levels of antibodies in blood increase significantly faster and to a higher level in the secondary immune response compared to the primary immune response.
An example of a vaccine is the coronavirus vaccine or the MMR vaccine (a weakened version of measles, mumps and rubella).
An example of a vaccine is the coronavirus vaccine or the MMR vaccine (a weakened version of measles, mumps and rubella).
Positives & Negatives of Vaccination
There are many positives and negatives of vaccination. One of the main positives is that an individual who is given a vaccination will likely become immune to the pathogen that the vaccination is for. This means that they are less likely to catch the disease or become seriously ill from the pathogen because they will have the more effective secondary immune response rather than the less effective primary immune response. However, vaccinations are not 100% effective, so not all individuals who have the vaccine will become immune to the pathogen.
Another positive is that we can vaccinate individuals who have a weakened immune system, so that there is less chance of these individuals becoming seriously ill from the pathogen. For example, we vaccinate the young, the very old and individuals with underlying health conditions. These individuals are usually prioritised for vaccination.
Vaccinations can also decrease the chance of epidemics happening. Epidemics are where there is a large outbreak of an infectious disease within a community or country. Vaccinations reduce the chances of epidemics because they reduce the number of individuals in society with the disease (the disease is less prolific in society). This reduces the chances of catching the disease for everyone in society, which benefits both the vaccinated and the unvaccinated.
Another positive of vaccinations is that some diseases have been eliminated by vaccinating individuals. For example, smallpox has been completely eliminated across the world by vaccinating individuals.
However, a negative of vaccinations is that some individuals may have a bad reaction to the vaccine. These bad reactions can take a variety of different effects, such as making someone feel slightly ill to more serious effects like seizures. Bad reactions to vaccinations are fairly rare, but it is something that needs to be considered when we are vaccinating individuals. When you have a vaccination, usually the nurse or doctor will tell you to come back to the clinic if you have a bad reaction to the vaccine.
There are many positives and negatives of vaccination. One of the main positives is that an individual who is given a vaccination will likely become immune to the pathogen that the vaccination is for. This means that they are less likely to catch the disease or become seriously ill from the pathogen because they will have the more effective secondary immune response rather than the less effective primary immune response. However, vaccinations are not 100% effective, so not all individuals who have the vaccine will become immune to the pathogen.
Another positive is that we can vaccinate individuals who have a weakened immune system, so that there is less chance of these individuals becoming seriously ill from the pathogen. For example, we vaccinate the young, the very old and individuals with underlying health conditions. These individuals are usually prioritised for vaccination.
Vaccinations can also decrease the chance of epidemics happening. Epidemics are where there is a large outbreak of an infectious disease within a community or country. Vaccinations reduce the chances of epidemics because they reduce the number of individuals in society with the disease (the disease is less prolific in society). This reduces the chances of catching the disease for everyone in society, which benefits both the vaccinated and the unvaccinated.
Another positive of vaccinations is that some diseases have been eliminated by vaccinating individuals. For example, smallpox has been completely eliminated across the world by vaccinating individuals.
However, a negative of vaccinations is that some individuals may have a bad reaction to the vaccine. These bad reactions can take a variety of different effects, such as making someone feel slightly ill to more serious effects like seizures. Bad reactions to vaccinations are fairly rare, but it is something that needs to be considered when we are vaccinating individuals. When you have a vaccination, usually the nurse or doctor will tell you to come back to the clinic if you have a bad reaction to the vaccine.