The world is depending on the success of vaccine programs to end the ongoing COVID-19 pandemic. To curb the spread of the virus, it is essential for a population to reach herd immunity, where a significant proportion has developed immunity to infection. There are currently 11 vaccines authorized/approved for use in multiple countries worldwide. According to clinical trial data, these vaccines have demonstrated relatively high efficacy in preventing COVID-19 infection. However, this does not mean that the vaccines will be as effective in the real world. Vaccine response can vary at an individual level and can be influenced by a multitude of biological factors, including the function of the microbiome.
The microbiome plays a significant role in immunity, and may be an underlying factor explaining why elderly people and those...