The pandemic is expected to remain in the United States for at least two years until 60% of the population becomes infected and herd immunity develops. A synthetic vaccine, which contains the mRNA of the virus or a modified version of a different virus, is being mass produced and tested on recipients for age, body weight, pre-existing conditions, etc. The Pfizer–BioNTech vaccine and Moderna vaccine are two most commonly used mRNA COVID-19 vaccines. | The pandemic is expected to remain in the United States for at least two years until 60% of the population becomes infected and herd immunity develops. A synthetic vaccine, which contains the mRNA of the virus or a modified version of a different virus, is being mass produced and tested on recipients for age, body weight, pre-existing conditions, etc. The Pfizer–BioNTech vaccine and Moderna vaccine are two most commonly used mRNA COVID-19 vaccines. |