How infectious is that virus? How good is free birth control? And what are in those supplements you're taking? This is Healthcare Triage News.

Our first story comes to us courtesy of NPR. They recently put out an awesome graphic that shows how contagious different human viruses are.

The gist of it is something known as R₀. It's a mathematical term that describes the average number of people who are made sick by another person in an outbreak. The higher the R₀ is, the more infectious the disease is.

A number of things can affect R₀. The amount of time you're infectious, how much virus is needed to cause an infection, and even how it's spread; these things can all matter.

Measles one of the most contagious human diseases has an R₀ of eighteen. That means without vaccination a person with measles will give it to eighteen other people. You can imagine how quickly that could spread through a community, but when you vaccinate the number drops to about zero.Mumps has an R₀ of 10. SARS and HIV are 4, but Ebola is 2. That's 'cause Ebola is hard to transmit.

Of course, Ebola is really, really deadly. There's a reason people are afraid of it, but diseases with a lower R₀ are easier to contain, especially when we work to do so, like we are right now.

Our second story comes from a recent study published in the New England Journal of Medicine. It described results from the Choice Project, which gave free contraception to 9,000 teenage women. Choice differed from many other projects in that of most teens chose a long-acting, reversible contraceptive or LARC.

Unlike condoms or even the pill, LARCs like IUDs of estrogen implants, require a doctor's visit and are more expensive, but they also work much better. More than 3/4 of teens age 14-17 in the Choice Project chose one of those two methods and more than 2/3 of teens age 18-19 did.

Sexually active teens in the United States have a pregnancy rate of about 159 per 1000. Those in the choice program had a pregnancy rate of only 34 per 1000. Sexually active teens nationally have a birth rate of about 94 per 1000, verses 19 in the choice program. And sexually active teens in the US have an abortion rate of about 42 per 1000. Those in the Choice Program had a rate less than 10.

If you remove the financial and access barriers to long acting birth control, more girls get it and fewer teen pregnancies, births, and abortions occur, something to think about.

And our last story is a quick warning about supplements. In the United States, dietary supplements aren't regulated nearly as thoroughly as drugs. Because of this, the ingredients in supplements can vary widely.

In the past some nutritional supplements contained 1,3-dimethylamylamine or DMAA, which is a stimulant. Recently though that was banned in the United States, United Kingdom, and other countries, 'cause it's associated with heart failure, stroke, and sudden death. DMAA had become more popular after ephedrine was banned in supplements in 2005, 'cause that was bad for you too.

So be it! But now savvy supplement makers are introducing a new substance known as 1,3-dimethylbutylamine or DMBA. DMBA hasn't been outlawed yet but 1,3-dimethylbutylamine is a really close analogue of 1,3-dimethylamylamine. I'd say "to the research," but DMBA has never been studied in humans, never, no studies.

Supplements are a huge business. Stimulants are added because they make you feel good, but they are unregulated, unstudied, and keep turning out to be harmful.

I'm often baffled by the fact that many of the same people who are so worried about artificial sweeteners or gluten can be so blasé about supplements. The former are well studied and safe for almost everyone, the later, you don't always know.