As moms have always known, a good night’s sleep is crucial to good health -- and now a new study led by a UCSF researcher shows that poor sleep can reduce the effectiveness of vaccines. The study is the first performed outside a sleep laboratory to show that sleep duration is directly tied to vaccine immune response, the authors said. The study, conducted while the UCSF researcher was a doctoral student at the University of Pittsburgh, will appear in the August issue of the journal “SLEEP.”