Men who get their vaccinations in the morning have a better immune response than when they get them in the afternoon, new research says.
The findings of two studies show that almost twice as many men produced two times the number of antibodies when they had their shot in the morning compared to those who got vaccinated in the afternoon.
"If we can replicate these findings in a randomized controlled trial, there would be implications for the time of day for vaccinating those at risk," the authors concluded.
A team of British researchers conducted two studies: one in which they vaccinated young men and women against hepatitis A and another in which they vaccinated older men and women against influenza.
Some study participants received their vaccines in the morning, while others received theirs in the afternoon.
The immune response among the women wasn't affected by the time of day they got their vaccines.
The findings are published in the journal Psychophysiology.
Abstract:
Preliminary evidence that morning vaccination is associated with an enhanced antibody response in men
Anna C. Phillips, Stephen Gallagher, Douglas Carroll and Mark Drayson
Variation in response to vaccination, particularly in vulnerable groups, provides a strong rationale for developing vaccine adjuvants. If there were consistent diurnal variation in immune response, this could inform a simple intervention for enhancing vaccine efficacy. Data from two studies are presented examining morning versus afternoon vaccine administration; in the first, hepatitis A vaccine was administered to young adults, and in the second, influenza vaccine to older community-based adults. Men, but not women, vaccinated in the morning mounted a better peak antibody response to both hepatitis A and the A/Panama influenza strain. These results indicate that it would be worthwhile testing this effect in a large randomized control trial with vaccination during time periods representing the extremes of hormonal and cytokine diurnal rhythms.
