While New Hampshire gradually loosens COVID-19 restrictions in hopes of restoring some sense of economic normalcy, the state should also be assembling an army of public health officials to trace the contacts of people infected with the coronavirus. That's according to Dr. Michael Calderwood of Dartmouth-Hitchcock Medical Center and Dartmouth's Geisel School of Medicine . "That's going to require a public health infrastructure we have not yet had and we need to develop, he says.