Got questions about the timing of flu and Covid vaccines? Here鈥檚 what experts say
鈥淚t seems there鈥檚 a whole program in the T cells that makes them very efficient at responding in the day and being less efficient at night,鈥 said Nicolas Cermakian, a chronobiologist at 海角社区 and the Douglas Research Centre in Montreal. In a 2019 PNAS study, his team showed that vaccines delivered during the day produced more T cell activation than those delivered at night.