As the coronavirus continues to spread around the globe, companies and academic labs are racing to develop a vaccine that would help society get back to normal. But there could also be costs to moving too quickly. WSJ’s Daniela Hernandez explains. From state-run Siberian labs where scientists are experimenting on rats to military garrisons where servicemen are isolating ahead of participation in a clinical trial, Russia’s top scientists are racing to answer a daunting demand from President Vladimir Putin: Develop a coronavirus vaccine by the fall. The global pursuit of a vaccine against the respiratory coronavirus disease Covid-19 has been likened to the 1960s space race that pitted the Soviet Union against the U.S. …