Coronavirus Variant Update!
by Adel Eldin, MD, FACC, FACP, MBA, GGA
A recent study was conducted by Oxford and Astra Zeneca in South Africa showed its vaccine did not protect people from getting infected with the variant against mild and moderate COVID infection as the study included more than 2000 participants. Pfizer/BioNTech and Moderna vaccine showed 95% efficacy before the appearance of the variant. Based on the laboratory studies, both companies say that the vaccine may be less effective against the variant.
Based on the research from Cambridge Institute of Therapeutic Immunology and Infectious Disease showing Pfizer/BioNTech vaccine successful protection against Kent variant ( B117). Up till now, two Covid vaccine doses are still considered to be optimal till further data become available. No data is available on whether any of the vaccines prevent virus transmission from one person to another. The public is hoping for the vaccination will deliver herd immunity by late summer or early fall to bring life back to normalcy.
There is ongoing research to assess if modifying the vaccine will yield protection against the new variants as the real challenge is to keep up with the rate of mutation of the virus. The new analysis showed a single dose of Pfizer/BioNTech vaccine gives people about 90% protection from COVID-19 by 21 days. In the meantime, people have to stay vigilant and follow the rules regarding wearing masks, social distancing, and proper hygienic measures which must continue after vaccination as the risk of infection can increase significantly after the first few days following vaccinations people become less cautious.
Remember, in the UK study, it was found that the effectiveness of the vaccine starts to develop 14 days after receiving the vaccine and gradually increases to 90% by day 21. This shows that the first dose is highly protective but it takes 21 days to achieve that protection. A Prime booster or a second dose offers a maximum response of 94-95% efficacy. So far, a single dose of Pfizer or Moderna vaccine yields an immune response above the threshold needed for protection against the current dominant strain in the USA.
It is expected that by the end of March 2021, the B117 variant is likely to be the dominant strain in the USA. The most important thing to remember that one dose may give people a false sense of security as it is not known how variants change what is known about the response to the first dose. No one knows how fast these new variants develop and the appropriate effective protective vaccine will take to be available to counter them. Some may suggest using the new vaccine as a booster shot. The core principle and golden role will remain, strengthen your immune system to fight any invading virus, bacteria, fungus, or any other pathogen!