Karlsson had the second best time in the semifinals and then set a personal record of 57.34. In the final, she polished that record and ran 56.71.
The American Akala Garrett won, in a world best 56.16. Michalea Rose, also from the USA, came third with a time of 56.86.
The silver is Sweden’s fourth medal during the JVM in Cali, Colombia. The night before last Thursday, Swedish time, Emma Sralla won gold in the discus and the previous day the decathletes Jacob Thelander and Elliot Duvert won silver and bronze respectively.