People participating in a COVID-19 vaccine delivery system trial wait for their turn at a COVID-19 vaccination center in New Delhi, India, Saturday, Jan. 2, 2021. India tested its COVID-19 vaccine delivery system with a nationwide trial on Saturday as it prepares to roll-out an inoculation program to stem the coronavirus pandemic. Saturday's exercise included necessary data entry into an online platform for monitoring vaccine delivery, along with testing of cold storage and transportation arrangements for the vaccine, the health ministry had said. (AP Photo/Altaf Qadri)

This undated photo provided by Arvena Peshlakai shows Arvena Peshlakai opening the gate to her sheep corral at her home in Crystal, New Mexico. She and her husband Melvin volunteered to participate in coronavirus vaccine trials on the Navajo Nation. As coronavirus vaccines were being developed around the world, few Native American tribes signed up to participate. The reasons range from unethical practices of the past to the quick nature of the studies amid the pandemic. Native researchers say without participation from tribal communities, tribes won't know which vaccine might best be suited for their citizens. (Courtesy Arvena Peshlakai via AP).

TIME FOR MOVEMENT AT 9 AM EST SATURDAY, JAN. 2 This undated photo provided by Arvena Peshlakai shows Melvin Luke Peshlakai, left, and Arvena Peshlakai at their home in Crystal, New Mexico. The couple volunteered to participate in coronavirus vaccine trials on the Navajo Nation. As coronavirus vaccines were being developed around the world, few Native American tribes signed up to participate. The reasons range from unethical practices of the past to the quick nature of the studies amid the pandemic. Native researchers say without participation from tribal communities, tribes won't know which vaccine might best be suited for their citizens. (Courtesy Arvena Peshlakai via AP)

This undated photo provided by Arvena Peshlakai shows Melvin Luke Peshlakai, left, and Arvena Peshlakai at their home in Crystal, New Mexico. The couple volunteered to participate in coronavirus vaccine trials on the Navajo Nation. As coronavirus vaccines were being developed around the world, few Native American tribes signed up to participate. The reasons range from unethical practices of the past to the quick nature of the studies amid the pandemic. Native researchers say without participation from tribal communities, tribes won't know which vaccine might best be suited for their citizens. (Courtesy Arvena Peshlakai via AP)