Top US health official visits Colorado to promote vaccines
U.S. Department of Health and Human Services Secretary Xavier Becerra tries on a Colorado-themed mask given to him by U.S. Rep. Jason Crow, D-Colo., during a visit to a pair of buses set up as traveling clinics as part of the state's "Vaccines For All" campaign Friday, June 18, 2021, in Aurora, Colo. The buses are being used to distribute COVID-19 vaccines. (AP Photo/David Zalubowski)

U.S. Department of Health and Human Services Secretary Xavier Becerra tries on a Colorado-themed mask given to him by U.S. Rep. Jason Crow, D-Colo., during a visit to a pair of buses set up as traveling clinics as part of the state's "Vaccines For All" campaign Friday, June 18, 2021, in Aurora, Colo. The buses are being used to distribute COVID-19 vaccines. (AP Photo/David Zalubowski)

Jun. 18, 2021 06:22 PM EDT
U.S. Department of Health and Human Services Secretary Xavier Becerra, center, greets Colorado Gov. Jared Polis, left, and U.S. Sen. Michael Bennet, D-Colo., during a visit to a pair of buses set up as traveling clinics as part of the state's "Vaccines For All" campaign Friday, June 18, 2021, in Aurora, Colo. The buses are being used to distribute the COVID-19 vaccines. (AP Photo/David Zalubowski)

U.S. Department of Health and Human Services Secretary Xavier Becerra, center, greets Colorado Gov. Jared Polis, left, and U.S. Sen. Michael Bennet, D-Colo., during a visit to a pair of buses set up as traveling clinics as part of the state's "Vaccines For All" campaign Friday, June 18, 2021, in Aurora, Colo. The buses are being used to distribute the COVID-19 vaccines. (AP Photo/David Zalubowski)

Jun. 18, 2021 06:00 PM EDT
U.S. Sen. John Hickenlooper, D-Colo., center, speaks to Department of Health and Human Services Secretary Xavier Becerra, right, as U.S. Rep. Jason Crow, D-Colo., looks on during a visit to a pair of buses set up as traveling clinics as part of the state's "Vaccines For All" campaign Friday, June 18, 2021, in Aurora, Colo. The buses are being used to distribute the COVID-19 vaccines. (AP Photo/David Zalubowski)

U.S. Sen. John Hickenlooper, D-Colo., center, speaks to Department of Health and Human Services Secretary Xavier Becerra, right, as U.S. Rep. Jason Crow, D-Colo., looks on during a visit to a pair of buses set up as traveling clinics as part of the state's "Vaccines For All" campaign Friday, June 18, 2021, in Aurora, Colo. The buses are being used to distribute the COVID-19 vaccines. (AP Photo/David Zalubowski)

Jun. 18, 2021 06:13 PM EDT
U.S. Department of Health and Human Services Secretary Xavier Becerra, center, speaks accompanied by Colorado Gov. Jared Polis, left, and U.S. Sen. Michael Bennet, D-Colo., during a visit to a pair of buses set up as traveling clinics as part of the state's "Vaccines For All" campaign Friday, June 18, 2021, in Aurora, Colo. The buses are being used to distribute the COVID-19 vaccines. (AP Photo/David Zalubowski)

U.S. Department of Health and Human Services Secretary Xavier Becerra, center, speaks accompanied by Colorado Gov. Jared Polis, left, and U.S. Sen. Michael Bennet, D-Colo., during a visit to a pair of buses set up as traveling clinics as part of the state's "Vaccines For All" campaign Friday, June 18, 2021, in Aurora, Colo. The buses are being used to distribute the COVID-19 vaccines. (AP Photo/David Zalubowski)

Jun. 18, 2021 06:03 PM EDT
U.S. Department of Health and Human Services Secretary Xavier Becerra heads to a podium to speak during a visit to a pair of buses set up as traveling clinics as part of the state's "Vaccines For All" campaign Friday, June 18, 2021, in Aurora, Colo. The buses are being used to distribute COVID-19 vaccines. (AP Photo/David Zalubowski)

U.S. Department of Health and Human Services Secretary Xavier Becerra heads to a podium to speak during a visit to a pair of buses set up as traveling clinics as part of the state's "Vaccines For All" campaign Friday, June 18, 2021, in Aurora, Colo. The buses are being used to distribute COVID-19 vaccines. (AP Photo/David Zalubowski)

Jun. 18, 2021 06:34 PM EDT
U.S. Department of Health and Human Services Secretary Xavier Becerra, center, and Colorado Gov. Jared Polis, left, greet well-wishers during a visit to a pair of buses set up as traveling clinics as part of the state's "Vaccines For All" campaign Friday, June 18, 2021, in Aurora, Colo. The buses are being used to distribute COVID-19 vaccines. (AP Photo/David Zalubowski)

U.S. Department of Health and Human Services Secretary Xavier Becerra, center, and Colorado Gov. Jared Polis, left, greet well-wishers during a visit to a pair of buses set up as traveling clinics as part of the state's "Vaccines For All" campaign Friday, June 18, 2021, in Aurora, Colo. The buses are being used to distribute COVID-19 vaccines. (AP Photo/David Zalubowski)

Jun. 18, 2021 06:30 PM EDT
U.S. Department of Health and Human Services Secretary Xavier Becerra at a Colorado-themed mask given to him by U.S. Rep. Jason Crow, D-Colo., during a visit to a pair of buses set up as traveling clinics as part of the state's "Vaccines For All" campaign Friday, June 18, 2021, in Aurora, Colo. The buses are being used to distribute COVID-19 vaccines. (AP Photo/David Zalubowski)

U.S. Department of Health and Human Services Secretary Xavier Becerra at a Colorado-themed mask given to him by U.S. Rep. Jason Crow, D-Colo., during a visit to a pair of buses set up as traveling clinics as part of the state's "Vaccines For All" campaign Friday, June 18, 2021, in Aurora, Colo. The buses are being used to distribute COVID-19 vaccines. (AP Photo/David Zalubowski)

Jun. 18, 2021 06:23 PM EDT
U.S. Department of Health and Human Services Secretary Xavier Becerra, center, greets well-wishers during a visit to a pair of buses set up as traveling clinics as part of the state's "Vaccines For All" campaign Friday, June 18, 2021, in Aurora, Colo. The buses are being used to distribute COVID-19 vaccines. (AP Photo/David Zalubowski)

U.S. Department of Health and Human Services Secretary Xavier Becerra, center, greets well-wishers during a visit to a pair of buses set up as traveling clinics as part of the state's "Vaccines For All" campaign Friday, June 18, 2021, in Aurora, Colo. The buses are being used to distribute COVID-19 vaccines. (AP Photo/David Zalubowski)

Jun. 18, 2021 06:33 PM EDT