Do the benefits of vaccination outweigh the risk of side effects?
The principle of vaccines
Vaccines safely expose disease-causing pathogens to the body, causing the immune system to respond. There are molecules called antigens on the surfaces of bacteria and viruses that cause diseases. These molecules stimulate the immune system to produce antibodies. Proteins called antibodies bind to antigens to kill or inactivate bacteria or viruses. Antibodies made in response to specific antigens can only respond to bacteria or viruses that cause certain diseases. In addition to pathogens, vaccine injections contain supplements that help the immune system respond well and substances that prevent contamination (Coelho, 2020).
When did vaccinations begin?
The national program for vaccination was first properly established and coordinated in the 1960s. This program has changed the public health of the world. In countries with good vaccine programs, many diseases that were the main causes of death for young babies have essentially disappeared. The youngest infant is greatly affected by the epidemic. For this reason, the state has created a vaccination program for the age at which vaccine protection can be effectively viewed. However, it is difficult to induce a strong immune response in infancy. One of the reasons is the interference of maternal antibodies. Maternal antibodies obtained through the placenta reduce the availability of antigens and viral replication. Even if people get a vaccine, it is not worth vaccinating if people get a disease. Therefore, many studies have been conducted on the immune responses of infants, and vaccines have been developed. As a result, according to a WHO report, deaths of children under the age of five significantly decreased globally from 93 deaths per 1,000 live births in 1990 to 39 deaths per 1,000 live births in 2018 (Pollard and Bijker, 2020).
The types of vaccines
- Live-attenuated vaccines
It is a vaccine that injects live bacteria or viruses that do not cause infection. These types of vaccines use viruses more commonly than bacteria and stimulate the immune system to make memory B-cells in the body. They are not suitable for people with weak immunity or poor health because they contain live pathogens. However, these vaccines can immunize people for life with just one or two doses. Live-attenuated vaccines can prevent the following diseases (Zoppi, 2020):
- Smallpox
- Yellow fever
- Measles, mumps, and rubella (MMR combined vaccine)
- Rotavirus
- Chickenpox
- Inactivated vaccines
Vaccines of this kind use heat or chemicals to kill bacteria or viruses and get injected into the body. They do not cause a strong immune response. Therefore, they need additional vaccinations over time. Since they are not strong vaccines, they may have fewer side effects than live-attenuated vaccines do. These can prevent the following diseases (Zoppi, 2020):
- Rabies
- Polio
- Flu
- Hepatitis A
- Subunit, recombinant, conjugate, and polysaccharide vaccines
These types of vaccines can cause very strong immune responses in the body because they use certain parts of the viruses or bacteria. Subunit vaccines separate certain antigens from the surface of the pathogen. Recombinant vaccines isolate genes that produce proteins from viruses or bacteria through genetic engineering. Conjugate vaccines separate parts of the pathogen’s external antigens and link them to strong carrier proteins using chemicals. The polysaccharide vaccines work similarly to the conjugate. These vaccines are suitable for people with weak immune systems or poor health. These can prevent the following diseases (Zoppi, 2020):
- Hepatitis B
- Human papillomavirus (HPV)
- Hib (Hemophilus influenza type b)
- Pneumococcal disease
- Meningococcal disease
- Whooping cough
- Shingles
- Toxoid vaccines
Toxoid vaccines use toxins produced by pathogens to create immunity in certain areas. The immune system created in this way responds only to specific toxins. Therefore, toxoid vaccines do not provide lifelong immunity and need to be replenished over time. These can prevent the following diseases (Zoppi, 2020).
- Diphtheria
- Tetanus
- mRNA vaccines
This vaccine has been developed for decades. This has the advantages of short manufacturing time and low manufacturing cost. It should be stored well at low temperatures because of its vulnerability. mRNA vaccines can prevent COVID-19 (Zoppi, 2020):
- COVID-19
- Viral vector vaccines
Viral vector vaccines modify other viruses and use them as vectors. Vectors protect against target viruses. These can prevent the following diseases (Zoppi, 2020).
- Adenovirus
- Influenza
- Measles virus
- Vesicular stomatitis virus (VSV)
- Ebola virus
- COVID-19
DNA and recombinant vector vaccines
DNA and recombinant vector vaccines are also called platform-based vaccines. DNA vaccines contain DNA that produces specific antigens of a pathogen. When injected into the body, the body creates DNA against bacteria, which makes the immune system work. Recombinant vector vaccines stimulate the immune system like a natural infection. It reproduces live viruses that carry extra genes from disease-causing germs. These genes create the protein that the immune system needs to recognize and counteract pathogens. It is currently under development (Zoppi, 2020).
The risks of vaccination
Vaccines have made a huge contribution to people’s health. Nevertheless, some people are reluctant to get vaccinated because of the side effects of the vaccines. Many studies on vaccines show that they are very stable. Common side effects of vaccination, especially those associated with early innate immune responses immediately after vaccination, are carefully recorded in clinical trials. Vaccine development is very tightly controlled and managed. The development of a new vaccine typically involves clinical trials for between 3,000 and tens of thousands of people. Therefore, common side effects are well known to the public and are officially announced by regulators when obtaining a vaccine license. Common side effects include symptoms such as injection site pain, redness, swelling, fever, discomfort, and headache (Pollard and Bijker, 2020).
Conclusion
With the development of medicine, the average life expectancy of humans has increased significantly compared to the past. This is because vaccines have made diseases that killed young children in the past disappear. In addition, diseases such as smallpox, which has killed many people, can be prevented with the development of vaccines. However, misinformation about vaccines spreads through social media, raising suspicions about the stability of vaccinations. Each person experiences different side effects from vaccines. Some may develop mild symptoms, but others may experience serious side effects of another illness that they did not want. According to medical research data, the stability of vaccination is very high. However, side effects cannot be ignored, even if the figure is very low. Therefore, the development of vaccines should be thoroughly and carefully managed, and their contents should be disclosed transparently. Most importantly, accurate information about vaccines should be well known to the public. In order to minimize the side effects and maximize the benefits of the vaccine, it is recommended to fully understand the vaccine to be vaccinated and obtain medical experts’ opinions if necessary.
References
Coelho, S. (2020). What is a vaccine? How do they work? [online] www.medicalnewstoday.com. Available at: https://www.medicalnewstoday.com/articles/what-is-a-vaccine#how-do-they-work [Accessed 2 September. 2022].
Pollard, A.J. and Bijker, E.M. (2020). A guide to vaccinology: from basic principles to new developments. Nature Reviews Immunology, [online] 21(21), pp.1–18. doi:10.1038/s41577-020-00479-7 [Accessed 2 September. 2022]
Zoppi, L. (2020). What are the Different Types of Vaccines? [online] News-Medical.net. Available at: https://www.news-medical.net/health/What-are-the-Different-Types-of-Vaccines.aspx [Accessed 2 September. 2022].
Ledger, J. (2022). Vaccines Are Important—But What Are They and How Do They Work? [online] Yale Medicine. Available at: https://www.yalemedicine.org/news/vaccine-basics [Accessed 2 September. 2022].
