Since the COVID19 pandemic has hit the world, many scientists have been putting their best foot forward to discover effective treatment and vaccines for the SARS-CoV-2 virus. The SARS-CoV-2 virus leads to COVID19 illness. Many COVID19 shots such as Pfizer-BioNtech and Moderna have been authorized for emergency use by drug regulators around the world. Recently, a team of experts in the UK has found that delaying the second dose of the Pfizer or Moderna vaccines further than the suggested gap of three weeks in the clinical trials of the vaccines might induce a more robust antibody response in elderly people. Soon after these shots have been authorized for emergency use, health officials from the UK have advised that the second dose of the vaccines should be given 12 weeks after the first dose. This decision has been taken in order to protect more people with the first dose of the vaccine. At that time, the UK has been reeling through the wrath of the COVID19 pandemic. A study has looked at 175 elderly people who have been in the age range of 80 to 99 years. These people have been given the second dose of the vaccine 12 weeks after the first jab instead of the recommended gap of three weeks as recommended by the companies. Experts have said that these people have been found to have 3.5 times greater antibody response as compared to people who have been given the second dose of the vaccine after a gap of three weeks.
Scientists have said that antibodies are just one part of the immune system that fights against foreign pathogens. Experts have said that the peak of T cell responses has been found to be higher in the people who have been given the second dose three weeks after the first dose of the vaccine. Experts who have been involved in the study have compared immune responses of the Pfizer-BioNtech vaccine from the three weeks dosing schedule that has been tested in clinical trials and the extended 12 weeks gap that has been suggested by the British authorities. The British officials have extended the dosing schedule to quickly provide some protection to people who are more susceptible to the virus. However, the companies Pfizer and BioNtech have said that there is no data available to prove that extending the dosing schedule will be able to provide enough immunity to people. The authors of the study have said that the study has observed how a delay impact COVID19 antibody levels and it will be beneficial for other countries to take a decision on vaccine scheduling that are facing vaccine shortages right now. One of the authors of the study, Helen Parry has said that there is a growing body of evidence that suggests that the decision taken by the UK government to delay the second dose has been beneficial. Most COVID19 vaccines are given to people in two doses, the first dose triggers an immune response, and the second one strengthens it further, said the experts.
There are currently three vaccines in the UK that are being used in the vaccine rollout program. Most of these vaccines feature a three to four weeks gap between both doses. However, in some vaccines, a longer gap between the first and second doses might result in a stronger immune response. The authors of the study have said that halting the COVID19 booster shot might shoot up partial immunity in a larger population as compared to a shorter dosing schedule. In the study, experts have calculated the levels of antibodies of the participants against the spike protein of the SARS-CoV-2 virus. They as well have assessed how immune cells that are known as T cells can help maintain the same antibody levels over time. The authors of the study have said that though the T cell response in the people who have been given the second dose 12 weeks after the first dose has been lower but it has not reduced the antibody levels more quickly over the nine weeks. The findings of the study are more specific to the Pfizer vaccine that is not available in low-income countries as of now. Therefore, countries need to find out whether variants spreading in their specific region might increase the rate of infection due to the extended gap between the first and the second dose. The study has not been peer-reviewed yet. The authors of the study have said that people should not draw any conclusions on how much protection they have based on which dosing schedule they have been given the vaccine.