The numbers we had all hoped to see dwindle by now … are rising instead: the number of people infected with Covid-19. The number hospitalized. The number in the ICU. The number who have died. What’s behind this surge, now, and what could tamp it down? Epidemiologist Dr. Lisa Maragakis, senior director of infection prevention for the Johns Hopkins Health System, admits public messages have been muddled ... but stresses that masks, social distance and hand-washing do work.