I do get a blood test every month, so I know when my neutrophils are low and I have to watch out for infections--washing hands often, not touching my nose or eyes after touching other people, etc. etc.
My biggest problem in traveling is keeping to my mostly vegetarian diet. At home, I live on smoothies made from fruit and tofu and milk, with added supplements, such as ground-up flax seeds. Hard to get that while traveling. When I visited Germany for a month, and ate the typical German diet with meat and potatoes, etc., my blood results were down afterwards. Not like visiting China, where my results were up!
Best wishes!