In Lin’s view, many who accepted the one-shot Johnson & Johnson vaccine did so because they were told not to be picky and to take what’s available. “I think the public-health system owes these people a pathway to the same level of vaccination as the majority of people who received the mRNA vaccine,” he said. For now, though, the CDC allows the mixing of the mRNA shots only in “exceptional situations.” Moore stressed we’re in a watch, wait, and planning phase regarding booster shots; the Delta variant is of biggest concern to those people who have not gotten any COVID-19 shot yet, be it the Johnson & Johnson shot or any other of the current crop of vaccines. “They’re going to get a rude awakening if Delta hits them,” Moore said. “You can run, but you can’t hide. Eventually the highly transmissible variant will find you.”