Having been rather unpleasantly under the weather lately, I've tried to be hyper-vigilant about ways to prevent infecting my wife and others unlucky enough to come into contact with me (trust me, they don't want what I got). Here are some tips on what not to do when you've got the cold, flu or Big D; ie, the habits of highly infectious people.
1. Making out whilst illin'
Not sure how long to wait before you can resume lip-lockin' with the one u love (or whomever) after you've come down with something? Refer also to #5, but researchers say that you should wait at least five days -- or longer, if, y'know, you really care.
2. Not washing your hands
This one seems pretty obvious, but I'm sure we've all been guilty of not washing our hands as much as we could when we're sick. After all, it's the simplest and -- barring the super-unlikely development of a cold vaccine -- still the most effective method of preventing the spread of the cold virus.
3. Picking your friend's nose
You know the old saying, "you can pick your friends and you can pick your nose ..." (I was always much better at the latter than the former, by the way.) Turns out you really shouldn't pick anybody's nose, especially when you're sick. According to the National Institute of Allergy and Infectious Diseases, "Much of the research on the transmission of the common cold has been done with rhinoviruses, which are shed in the highest concentration in nasal secretions."
4. Using human waste as fertilizer to grow food
You gotta admit, it's a pretty cheap and abundantly-available resource, which is why a lot of developing nations use it to grow their crops. And while the locals might be used to that sort of thing -- and the parasites which subsequently infect those fruits and veggies -- tourists aren't, and will pay mightily for the indulgence ... in the john.
5. Hanging out in crowds after you've been sick for three days
Studies have shown that colds are most easily transmittable between the second and fourth day of infection, so if you've been sick for a couple of days already, do us all a favor and skip the office President's Day party this year.
6. Taking lots of aspirin when you have a cold
Researchers say that using aspirin to treat colds increases the amount of "virus shed" in nasal secretions -- making your snot even more potently infectious, in other words -- and the cold sufferer more of a hazard to others.
7. Pooping in the pool
It sounds silly, but it's pretty serious; that kind of bacteria travels quickly and it doesn't take much to make people seriously ill. In 1998, for instance, 26 kids at an Atlanta water park were infected with E. coli, killing one of them and causing permanent damage to several others, all because one sick person couldn't hold it.