IM injected vaccines are primarily intended to generate both antibody mediated and T cell mediated immune reactions. 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) offers till day (February 8, 2022) affected hundreds of millions of people while leading to >5.7 million deaths worldwide.1 A very rapid global spread of COVID-19 posed QX 314 chloride an international health emergency like a devastating pandemic of the 21st Century. Though several medicines, treatments, and immunomodulatory regimens such as remdesivir, ivermectin, dexamethasone, convalescent plasma therapy, antibody-based immunotherapies, and monoclonal antibodies (MAbs) have been identified and used in emergency purposes for reducing the disease severity in individuals with COVID-19 as well as others are becoming investigated; however, the choice of effective curative medicines and medicines are QX 314 chloride yet to be identified.2C7 Numerous study advances QX 314 chloride paved the way for developing multiple COVID-19 vaccines in less than a 12 months by exploring several vaccine platforms and advances. After very high attempts, experts have developed COVID-19 vaccines such as mRNA vaccine, DNA vaccine, viral vector vaccine, virus-like particles (VLPs), recombinant vaccine, protein subunit-based vaccines, live attenuated and inactivated computer virus vaccines that are becoming utilized for vaccinating people across the globe under different vaccination programs that are in progress in several countries. A few Rabbit Polyclonal to ATG16L2 vaccines have been authorized for use, and vaccination programs are currently underway in various countries8C12 while others newer and versatile vaccine production platforms including recombinant vaccines, plant-based vaccine, immunoinformatics-based multi-epitope subunit vaccine, artificial intelligence, and CRISPR/Cas technology-based vaccine, nanotechnology-based vaccines (nano-vaccine) as well as others will also be under high progress and currently in the pipeline for developing appropriate vaccine candidates to counter SARS-CoV-2.11C18 Different kinds of vaccines in use have shown a high degree of effectiveness with variable protective levels of up to 95% (70C95% range) in vaccinated individuals against COVID-19.2,3,12,19C21 In the era of various improvements in developing vaccines, few issues of issues, debates, and difficulties related to vaccines include induction of variable protective levels, defining booster doses, the feasibility of computer virus re-infection and end result of disease program in vaccinated individuals particularly amidst emerging variants and mutants, need for further modifying the vaccines as per main mutants/variants, levels of herd immunity developed, independent clinical tests in elderly, pregnant women and children or need same/special vaccine for these, vaccine hesitancy, diplomacy, and equitable access to the worldwide populace and completing vaccination process at the earliest of worldwide populace, these need to be addressed adequately.22C33 Currently, all available COVID-19 vaccines QX 314 chloride are administered by intramuscular (IM) injection, which is an invasive method, while many experts are focusing on developing an effective vaccine that can be administered through nose or oral routes. For instance, in mucosally transmitted ailments like influenza and SARS-CoV-2 viruses, administering immunizations through the nasal route is regarded as extremely appealing since it induces a dual systemic and a strong local mucosal immune response. Since there is no need for qualified medical personnel to deliver IN dose, the nose vaccines would have higher ease to administer and render desired effectiveness. This is advantageous, particularly in developing nations, and therefore nose vaccination provides a more cost-effective and easy approach to administering vaccinations during disease outbreaks.34,35 COVID-19 approved vaccines delivered intramuscularly elicit antibody mediated and cell-mediated immunity in order to avoid viral replication and to provide resistance against the development of COVID-19. However, existing IM vaccinations are meant to induce systemic immune response without generating mucosal protection. Consequently, protections offered by IM vaccines may not be sufficient to deal with computer virus replication and dropping in the top respiratory and so may not quit nose SARS-CoV-2 illness. The absence of a local secretory IgA (sIgA) antibody immune response could present a risk of SARS-CoV-2 transmission from vaccinated people as they still.