Why is it that when a person vomits, it causes others to vomit — even when they don't have an illness causing it? Is this something triggered by the brain or is it something that happens by reflex (survival instinct) for someone to vomit since, perhaps, what the first person was eating may affect the second who vomits as well?

I'm HIV positive, very low viral load & great t-cell count (not on meds). I've been reading recently that flu shots aren't all they're cracked up to be. What are the dangers of a flu shot, and if my immune system is already doing well, should I still get a flu shot?

Does a person's menstrual cycle regulate her bowels in any way? I have had some problems. The week before I get my period, I have loose bowels and the week afterwards I am quite constipated. Is this normal? Is there anything I can do?

I have had Crohn's disease for 16 years and am in remission right now. Recently my boyfriend and I have been toying with the idea of anal sex, but I'm concerned about it given my health issues. I have a lot of thickening of the terminal ileum walls and worry that the "trauma" of anal sex could set off a flare up and be painful because of the narrowing. Any thoughts? I'm way too embarrassed to discuss this with my male doctor. Thanks!

What natural food or herb can help soothe stomach ulcers?

I've been hearing a lot on the news about the new virus [novel coronavirus, COVID-19] and I'm seeing students on campus wearing masks. The news seems to have conflicting information and I'm not sure what to do. Should I be worried? Do I need to wear a mask too? Thank you.

When is a person with a cold contagious? A couple of friends, who are put off when I keep my distance from their sneezing and coughing, insist one is only contagious a week or so before symptoms appear. In the back of my memory is the idea that one remains contagious until a few days *after* primary symptoms disappear. I'm not usually so concerned about this, but I'm coping with a couple of other annoying health problems and want to try to avoid adding a cold or flu, to boot. I do the usual things news shows recommend — eat well, wash hands frequently. But when should one avoid others who have colds, or when should one stay isolated at home when one has a cold (or flu)?

1) I'm a college student and I've heard in the media that meningitis vaccine shots are recommended. How do I get more information and a shot?

2) As a parent of a college freshman this fall, I was concerned about the increasing publicity that Meningitis has received recently over the networks. Since the population most likely to be infected includes young adults living in close quarters, do you recommend vaccination and where is it available?