The COVID19 vaccines are the best way to get a preeminent kind of immunity against the SARS-CoV-2 virus and its other variants at present. However, a new study has indicated that vaccines might not be a sure-shot solution to prevent the virus in long term. The lead author of the study, Robert C. Gallo from the University of Maryland School of Medicine, and his colleagues from the Global Virus Network have said that giving vaccines such as polio, measles, and tuberculosis (TB) that are designed with weakened viruses might be able to shoot up innate immunity against COVID19. The findings of the new study have been released in the journal PNAS. The authors of the study have said that vaccination is required to put a stop to the COVID19 pandemic but some countries around the world are not able to speed up vaccine rollout plans the way western countries are conducting their vaccination. As per the report, some nations are going to start their immunization programs in 2022 that will leave them vulnerable to more deadly and potentially immune-evasive strains of the virus. Innate immunity can be defined as an immediate reaction of the body to a virus, said the experts. The authors of the study have said that innate immunity takes just a couple of minutes to develop unlike adaptive immunity, which can take days and hours to produce T cells and antibodies. Past studies as well have shown that innate immunity alone is enough to put up a fight against the virus and infection.
The authors of the new study have shown that innate immunity lies in its broad, non-specific activation and the ability to reduce multiple kinds of viruses. In the case of the SARS-CoV-2 virus, innate immunity is prompted by spotting the nucleotide sequence of the RNA of the virus. Scientists have said that immunity induced by the flu and HIV vaccines can remain the same as long as adaptive immunity. They have claimed innate immunity as well carry innate memory that trains the immune system to detect a foreign virus. Experts who have been involved in the study have said that innate immunity can prevent infection from the SARS-CoV-2 virus; however, it depends on its success in preventing other coronaviruses such as MERS and SARS. The study has found that coronaviruses that are derived from bats are linked with a suitable balancing of innate immune retorts between resistance and tolerance. Experts have said that bats are found with high levels of NK cells and IFN expressions, which show that innate immunity is required to prevent the SARS-CoV-2 virus. Scientists have said that hoarding COVID19 shots and mistrust against the rapid vaccine development have acted as a major barrier to reach herd immunity. In such a case, administering older vaccines that have been in use for years and that are widely available might resolve the issue.
Experts have claimed that older vaccines that are designed with the inactive virus might help as they target specific pathogen of interest. They also offer a wide range of protection against other viruses as well. Many studies that have been done in the past decades have found that non-specific effects of these vaccines can be increased with booster shots. For example, some animal studies have shown that the H3N2 vaccine can offer protection against respiratory syncytial viruses by shooting up cytokine levels and leukocytes in the body. The authors of the study have seen greater protection against COVID19 in health care workers who have been vaccinated with Bacillus Calmette – Guerin vaccine against TB. Other studies as well have supported the findings of the new study by analyzing fewer symptoms of COVID19 or fewer cases of severe COVID19 in these people. Experts have said that reusing older shots is cost-effective as well to stimulate innate immunity. They have claimed that some COVID19 shots are needed to be stored in refrigerators, which is an expensive affair. They have said that it will be more cost-effective to administer these shots as booster shots for added immunity rather than waiting for the second dose.