As California coronavirus cases spike, contact tracing stalled by fear and embarrassment

Daniel Parker, an assistant professor of public health at the University of California, Irvine, who is training tracers in Orange County, said they really need to get in touch with someone’s contact within three days of a positive test result to intercept transmission of the disease. But if it takes a week or more to get the results, “you have to question whether it’s worthwhile at that point,” he said.