occurred last yearthe uk recently went through a spike in infections driven by the delta variant despite having fully vaccinated 56 of its population according to the bloomberg vaccine trackercases there topped 50000 a day close to the level of the countrys winter surge but unlike the winter peak there has been little corresponding rise in hospitalizations or deaths a sign that the wide use of vaccines has prevented infections from becoming severeyet in the us where case counts are following a similar trajectory the outcome is less certain parts of the country in particular the east and west coasts have vaccination levels in line with the uk but in the central and southern parts of the us the share of people getting shots has lagged badly and hospitalization rates are risingin missouri and arkansas two of the states with the worst ongoing outbreaks hospitalizations are at levels not seen since january in younger age groups such as those ages 3059 new hospitalizations have already passed the us winter peak and continue to rise