my dad had it in his 30s. no drinking problem. worked his ass off. very fit. he was no sicker than the chickenpox we got. that being said shingles can scar the fuck out of you, but i think thats if you start scratching yourself. soldiers get dosed up with fuckloads of things when they sign up, then get dosed up again if they get deployed, no idea about US military but i know multiple diggers here who all copped a different test in a different finger at the same time and couldnt touch shit for about a week afterwards if anything reacted. most er.... immunity? tests i think im thinking of, involve a subdermal injection of liquid, so just under the skin. if you have the antibodies of the disease youre being tested for (as in, youve had it before, your body recognises it, and reacts to it) you end up with a bigger reaction from the test, or the opposite (depending on whats being tested) - I had a mantoux test for tuberculosis on my upper arm that reacted badly and has left a thumbnail sized scar on my shoulder, i thought that meant id never had it but reading now it looks like i might have been exposed to TB before i had it. Either way, was good to go to europe after.... i was only 16 at the time and was sent to Travellers Medical and Vaccination Centre simply because thats what we thought you were meant to do. From what i can tell people actually having those tests and vaxxes to go overseas were always fucking rare so.... /me shrugs