The Safety and Effectiveness of mRNA-1273, ???162b2, BNT162b1, ChAdOx1-nCoV-19 Vaccines Against Covid-19

COVID-19 disease is an infectious disease caused by the SARS-CoV-2 virus which has become a pandemic in the last year and a half. Because of this virus since October 2019, more than 1,000,000 deaths have been caused and for this it was imperative to develop a drug or vaccine. SARS-CoV-2 usually causes mild to moderate symptoms in most people such as dry cough, fever, myalgias which are similar to the symptoms of the flu virus. Also, many people who are infected with the virus do not show any symptoms, they are carriers of it and this is the main cause of its global spread. Vulnerable groups consisting of the elderly, people with chronic or underlying diseases, pregnant women and young children are at the highest risk due to their weakened immune system and often need hospital treatment in case of COVID-19 disease. The main purpose of this literature review is to evaluate the safety and efficacy of some vaccines developed against COVID-19, namely the Pfizer (BNT162b1 and BNT162b2), Moderna (mRNA-1273) and AstraZeneca (ChoOX1) vaccines. -19). The materials used in the articles were each experimental vaccine separately in different doses (or not), the placebo vaccine selected in each study and some methods of measuring the immune response such as measuring IgG or measuring cellular responses or measuring of the interferon-c intermediate. The results of the six articles analyzed showed that all vaccines were considered sufficiently safe for use as they showed mainly local reactions lasting a maximum of 48 hours and systemic reactions were minimal. In fact, the side effects in all 3 vaccines were milder in the elderly group than in younger people. Regarding the efficacy after the administration of both doses, it seemed that the highest is available from the Pfizer vaccine (95%), then Moderna (94.1%) and finally AstraZeneca (63%). Note that the immune response elicited by all 3 vaccines was almost the same for all age groups. However, the selected articles also had some limitations such as that they did not include all or none of the vulnerable groups or that the participants were not from many different countries or that the number of people was not large enough to be generalized with certainty all the conclusions. Therefore, further studies that follow will review these results by removing all existing limitations. In conclusion, the data obtained on vaccines appeared to be quite encouraging in tackling the pandemic through prevention and especially in protecting vulnerable groups that are a priority.