The National Institute of Allergy and Infectious Disease at NIH reported on its website how the agency’s decades-long support helped to develop a safe and effective COVID-19 vaccine. The agency acknowledged that animal studies will continue to be essential in providing vital information as new SARS-COV-2 variants emerge. Before a vaccine can be tested in humans, the U.S. Food and Drug Administration requires a vaccine to be tested in animals to ensure safety and effectiveness.

Mice are typically used as they have a well-characterized immune system, defined genome, and rapid reproduction process. By generating mice that expressed the human ACE2 protein, researchers were able to gain insight on information surrounding COVID-19 symptoms and its disease course. Syrian hamsters also are an important animal model used in COVID-19 research as researchers noticed how older male hamsters developed the disease more severely than young female hamsters. These hamster models have allowed for the further evaluation of investigational COVID-19 vaccine candidates, immunotherapies, and antiviral drugs.

The use of nonhuman primates in the development of a COVID-19 vaccine helped provide advantages for clinical translation. Nonhuman primates are genetically more similar to humans than mice. The similarities in innate immune responses and B- and T-cell repertories allowed for the use of clinically relevant vaccine doses.

Check out the full report: https://www.niaid.nih.gov/news-events/role-animal-research-mrna-covid-19-vaccine-development