Our immune system is the strongest defense we have against disease. mRNA, or messenger Ribonucleic Acid is the breakthrough vaccine technology used by Moderna and Pfizer-BioNTech pharmaceutical companies to tweak our immune system to protect us against the COVID-19 virus. The companies using mRNA technology instruct the immune system to manufacture neutralizing antibodies to fight COVID. Currently, these vaccines are more than 90% effective in preventing COVID-19 hospitalizations and deaths.