Vaccination is a very hot topic and so could potentially be asked about at interview. There are many aspects of mass vaccination that can be potential questions: the scientific basis of vaccination, ethical aspects of mass vaccination schemes and the public health implications. The principles of how immunity is achieved through vaccination are discussed in biology GCSEs and A-Levels.
The first vaccine was developed in 1798 by Edward Jenner, he used the mild cowpox virus to protect against the deadly smallpox virus. Since then, millions of vaccines have been delivered and successfully prevented millions of deaths. Vaccination induces the immune response by stimulating the natural response with a less dangerous form of the pathogen. This reduces the risk of fatal complications from infections. The immune system works to protect us from different foreign particles. When an organism such as a virus or bacterium enters the body, immune cells recognise the non-human antigen and produce various other cells to help eliminate it from the body.
Vaccines can consist of weakened live forms of the virus, inactivated, extracts of the microorganism, vectors of the virus or nucleic acid from the virus. The different forms can give immunity for different lengths of time and so some may need to be repeated as boosters. Immune response to flu vaccination takes 2 weeks to develop and so should be given before flu season starts. When initially injected, the pathogen causes the activation of the innate immune system. This involves the production of various proteins and cells immediately. This then induces the activation of the adaptive immune system with B and T cells. Within the adaptive immune system are memory cells which remain in circulation after the pathogen has been cleared. The memory cells expand when the pathogen re-enters the body. The quick reproduction of the memory cells allows for the rapid clearance of the pathogen to prevent illness.
The various types of flu vaccinations are different versions of inactivated influenza virus. They can be administered nasally or via injections, depending on the population being vaccinated. The flu vaccine given each year is a new variation of the vaccine. In the UK, the vaccine given is designed from genetic information of the flu season in the southern hemisphere and previous influenza seasons. Influenza viruses are isolated and analysed worldwide. With the decrease in flu season due to decreased social contact from the SARS-CoV-2 pandemic, the prediction of the best vaccines has become more difficult.
Currently, the UK is running an extended flu vaccine campaign. The COVID mass vaccination programme has given the infrastructure to enable a greater proportion of the population to be vaccinated. The list of those eligible for free flu vaccines is as follows:
· all children aged 2 or 3 years on 31 August 2022
· all primary school-aged children (from reception to Year 6)
· those aged 6 months to under 65 years in clinical risk groups
· pregnant women
· those aged 65 years and over
· those in long-stay residential care homes
· carers
· close contacts of immunocompromised individuals
· frontline healthcare staff
· Secondary school students, prioritising Years 7, 8, and 9
· Healthy 50- to 64-year-olds
By vaccinating these groups of people, the aim is to protect the most vulnerable in society and to achieve herd immunity to limit the spread of the virus.
There is some mistrust surrounding vaccines in the general public. Following the MMR vaccine controversy in the 1990s, there was a lot of distrust in vaccinations and the public uptake of vaccines dropped significantly. With the rapid development of the COVID-19 vaccine, there was doubt about the efficacy and safety of the vaccine which hampered the mass vaccination campaign. Currently, 75.5% of the UK is fully vaccinated against COVID. The uptake of flu vaccines varies across different age groups.
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