I have a confession to make: though I’m a regular tampon user, I haven’t given much thought to Toxic Shock Syndrome (TSS). Perhaps you’re in the same boat. Since TSS is extremely rare, the topic is tempting to ignore. But there’s been a recent increase in the number of cases, and you may have read about a model who lost her leg to TSS last year. So, we thought it’s a good time to review the details.

What is it, actually?

TSS is an infection caused by a bacteria called Staphylococcus aureus which lives in the nose and on the skin of at least 20% of the population. The bacteria, if already present in or on your body, can grow in the material of a tampon and produce a harmful toxin that can be potentially fatal if left untreated. Symptoms of TSS include fever, low blood pressure, vomiting, diarrhea, skin rashes that appear like sunburns (usually on the hands and feet), and dizziness.

Though most people associate TSS with tampon use, 50% of cases are caused by non-menstrual factors, including surgical complications, postpartum wound infections, and even nosebleeds. In fact, 25% of non-menstrual TSS cases occur in men. And here’s some more good news: though many of us are carriers of the bacteria, the incidence of TSS is very low: about 1 in 100,000 people annually. That’s a 0.001% chance.

A Little History

TSS was relatively unheard of until 1980, when a sudden spike in cases caught the attention of the CDC (Centers for Disease Control and Prevention). Upon investigation, the CDC found a close association between TSS and tampon use, particularly ultra-absorbent kinds.

The spike in cases appeared to be the result of a new trend in the tampon industry. For decades, women in the US had been using tampons made out of cotton, but in the 1960s, manufacturers began adding synthetic materials to increase absorption while keeping costs down.

One tampon, in particular, was implicated in the outbreak. Introduced to the market in 1978 by Procter & Gamble, “Rely” was a hyper-absorbent tampon composed entirely of synthetic materials and designed to expand both lengthwise and widthwise. Rely soaked up so much fluid that some women claimed they could use just one tampon for an entire period.

According to Dr. Philip M. Tierno, a NYU professor and leading TSS researcher, Rely’s synthetic ingredients acted like a petri dish, providing the perfect environment for staph bacteria to grow and proliferate.

Once Rely was pulled from the market and the FDA promulgated a TSS-warning label on tampon packages (and detailed usage instructions), the number of cases dropped dramatically. However, the FDA did not take any action to compel companies to add all ingredients on the label as well.

How to Reduce Your Risk

Since the 1980s, studies have confirmed a link between tampon absorbency and a woman’s risk of getting TSS. Researchers have also found that synthetic materials are more likely to form an ideal breeding ground for staph bacteria than cotton alone. Dr. Tierno recently told VICE that “100 percent cotton tampons provide the lowest risk, if any risk at all.”

Based on expert advice, here’s what you can do to lower your risk of getting TSS:

1.) Use the lowest absorbency tampon possible.
2.) Change tampons every 4-8 hours. (If you plan to have a long night’s sleep, you may want to use a pad or set an alarm clock at the 8-hour mark.)
3.) Know the signs and symptoms of TSS (listed on package inserts, in case you forget). If you develop symptoms, immediately discontinue tampon use and contact your doctor.
4.) Use 100% cotton tampons. (LOLA users – you’re good with this one!)

By the way, switching to menstrual cups may not lower your risk, since they’re now linked with a documented case of TSS. Stay vigilant, my fellow tampon-wearers!

Angelika Schlanger, PhD, is a Yale-trained-researcher, Health Coach, blogger, food-system reformer, and mom to three healthy eaters (well, sometimes). She helps institutions, individuals, and families create a balanced wellness program that is tailored to their individual needs. Angelika enjoys concocting healthier versions of classic recipes, growing her own organic veggies, and taking long naps on the beach. Read her articles and tips at homehealthlove.com and follow her on Twitter @homehealthlove.