By Michael Erman (Reuters) – The U.S. National Institutes of Health is in talks with Pfizer Inc about studying whether a longer course of the drugmaker’s COVID-19 antiviral treatment Paxlovid is needed to prevent reinfections, top U.S. infectious diseases expert Dr. Anthony Fauci said on Wednesday. “We’re going to be planning what studies we’re going to be doing relatively soon, within the next few days” in order to determine whether or not a longer course is needed, Fauci said during a White House COVID-19 briefing. Rising COVID-19 cases in the United States are driving up use of therapeutics…