A positive outlook, even just on the day of receiving a vaccine, as well as strong social ties and a happy relationship can help increase antibodies made in response to a shot
Source:
https://www.newscientist.com/article/mg24933173-900-you-can-boost-a-vaccines-effect-with-good-moods-and-good-friends/?utm_campaign=RSS%7CNSNS&utm_source=NSNS&utm_medium=RSS&utm_content=home