What are the current options for COVID-19 vaccinations and how are they given?
There are 3 updated COVID-19 vaccines available in the United States. They all are updated to better match the current Omicron lineage variants. The most recently approved vaccine is Novovax which differs from the other two vaccines in that it is a protein based vaccine.
The updated Pfizer-BioNTech and Moderna vaccines are mRNA based vaccines. A person can get any of these three vaccines regardless of what vaccine they previously received (or if it is their first COVID-19 vaccination).
The “Johnson and Johnson” (Janssen) vaccine is no longer available in the United States.
The vaccine developed by the biotech company BioNTech, manufactured and marketed by Pfizer going by the brand name COMIRNATY is available in updated formulations for ages 6 months and above. For people aged 5 years and older the Pfizer-BioNTech vaccine is given just as a single injection. For children 6 months up to 5 years of age it is given as part of a series of 1-3 injections depending on how many COVID-19 vaccinations they have previously received.
The vaccine developed by Moderna has also been updated for the newer variants. The brand name of this vaccine is SPIKEVAX. For people aged 5 years and older the Moderna vaccine is given just as a single injection. For children 6 months up to 5 years of age the updated Moderna vaccine is given as 1 or 2 injections depending on how many COVID-19 vaccinations they have previously received.
How effective are the updated COVID-19 vaccines?
In clinical trials the updated vaccines produced marked increases in neutralizing antibody levels against Omicron lineage variants that are currently circulating. As we accumulate more data we will get a better idea of how this translates into real world protection.
Last year’s updated vaccine did provide very significant protection in the real world even for younger adults. See this article for details.
Are the Omicron variants milder than previous variants?
It is difficult to say how dangerous the Omicron variants are compared to previous SARS-CoV-2 lineages since most people in the US have been vaccinated and/or had COVID-19.
Recently a study looked at this question. Researchers took advantage of the fact that in Hong Kong there was a large percentage of the population that had not had COVID-19 or had been vaccinated. Hong Kong had for much of the pandemic adopted measures that severely limited the transmission of the virus. Using this population the researchers determined that the Omicron variant was not less likely to cause severe disease in those who had not had COVID-19 or were not vaccinated than the ancestral virus. Indeed the data showed a trend towards the Omicron variant being more dangerous although the findings were not statistically significant.
There have been other analyses that have come to similar conclusions. The conclusion is that we are seeing less severe COVID-19 not necessarily because of something intrinsic to the virus. We are seeing less severe disease for several reasons. First there is the fact that in the United States a large portion of our population has varying degrees of immune protection from vaccination and or from surviving infection. In the US we also have access to very effective antiviral medications and the treatment of those hospitalized with COVID-19 has improved.
Shouldn’t the SARS-CoV-2 virus naturally become less likely to cause severe disease?
There is a common perception that the virus will naturally become less dangerous. This is not necessary what will happen.
While it is true that if a virus kills you immediately it is not likely to get passed on since the virus relies on your cells to replicate itself. If the virus kills you quickly there will not be much time for the virus to get passed on to another person. However, people infected with SARS-CoV-2 will be infectious for days or weeks before the virus kills the person. A person can also spread the virus for many hours or days before that person gets sick. A person can even spread the virus if they never do get sick. Therefore there really is not a significant selective pressure on the virus to become less likely to harm humans in the near future.
See this article for more infromation on the immune system versus SARS-CoV
See this article for more information on the immune system versus SARS-CoVicleSee for mo information on the immune system versus SARS-CoV-2:
See this article for more information on the immune system versus SARS-CoV-2:
References for “Tis the Season for Respiratory Illnesses” Supplemental Information: COVID-19
Intrinsic and Effective Severity of Coronavirus Disease 2019 Cases Infected With the Ancestral Strain and Omicron BA.2 Variant in Hong Kong The Journal of Infectious Diseases, Volume 228, Issue 9, 1 November 2023, Pages 1231–1239, https://doi.org/10.1093/infdis/jiad236
Listen to a discussion of the this article by an infectious diseases specialist at the 9 minute and 25 second mark of this presentation:
Comments