For health experts to continue to make advancements in contact tracing, they need newly infected people to have the ability to remember everyone they have come in contact with over the past several days. That procedure will be difficult with people coming in after attending mass gatherings. The process also relies on the public’s trust in government. “These events that are happening now are further threats to the trust we need,” Dr. Sandro Galea, dean of the Boston University School of Public Health, told the AP. “If we do not have that, I worry our capacity to control new outbreaks becomes more limited.”