HALIFAX, ENGLAND - JULY 31: Dr Lisa Pickles draws up the Pfizer-BioNTech COVID-19 vaccine at a new ‘Pop Up’ vaccination centre in the Big Top of Circus Extreme in Shibden Park on July 31, 2021 in Halifax, England. The pop-up clinic will be situated just outside the UKs largest circus Big Top so even people who do not have tickets to the show will still be able to get their vaccine. All adults in England have been able to book a first dose since June 18, but the latest figures show that nearly a third of young adults (aged 18 to 29) in the country have still not had one. (Photo by Ian Forsyth/Getty Images)