Latin American countries begin offering booster shots

• The three countries initially used the less costly and more available Sputnik and Sinovac vaccines, which studies show have lower efficacy against variants.
• People there are now being given AstraZeneca and Pfizer doses, in a real-time experiment of mixing-and-matching.

But, but, but: Most other countries in the Americas have yet to start vaccinating many of their residents.

• The Pan-American Health Organization announced last week it will begin buying vaccine doses to distribute directly in the region, as wealthier countries drain those available through COVAX for their booster shots.
• Latin America and the Caribbean are being hit concurrently by the Delta, Lambda and Gamma variants of SARS-CoV-2.

For reference: In the U.S., recent vaccinations are reaching more Hispanic and non-Hispanic Asian and Black people who had lagged in vaccine access.

• Data compiled by the Kaiser Family Foundation shows the share of vaccinations going to Hispanic people increased significantly towards August in the 40 states that report ethnicity.

Watch: Axios' Stef Kight and Axios Latino co-author Russell Contreras talk with Texas Rep. Veronica Escobar and cardiologist Juan Rivera at an Axios Latino event about building confidence around vaccines and other health care issues.