We have been bombarded with statistics during the COVID 19 pandemic. It certainly was important to know the magnitude of the illness. Worldwide, more than 2 million people have died from COVID 19. The vaccines needed to control this pandemic have been developed within an extraordinarily swift time frame. The efficacy of the vaccines is measured by their ability to reduce the incidence of severe disease and death. The two-shot nature of the Pfizer and Moderna vaccines means that not all of the immunity is accomplished with the first shot and everyone must get the second shot to benefit from the more than 90% efficacy.

Age and sex do not appear to be prominent factors in modulating vaccine immunity, but the role of sleep is unclear. Previous studies have shown that sleep duration at the time of vaccination against viral infections can affect the immune response. For example, 10 days after vaccination against seasonal flu virus, patients who had their sleep restricted to only 4 hours had only half the antibody levels as those with normal sleep. A lower secondary response to hepatitis B vaccination was noted in patients with shorter sleep durations. Oddly enough, sleep at night doubled the cellular immunity against hepatitis A virus.

There are many other complex examples of immune responses affected by sleep patterns. The time of day when vaccines are administered may also play a role in the immune response. Best advice at present; get a good night’s sleep.