Each non-Leap Year, Rare Disease Day is observed on February 28. I say it’s observed on February 28 rather than it is on February 28, because RDD is actually February 29. Like Leap Year babies, RDD chooses February 28 as its backup day of observance in all years that cannot be evenly divided by 4 (and also in years that can be divided by both 4 and 100, but not also 400 – have you ever read the actual rules for Leap Day?!).

It’s fitting that February 29 should serve as Rare Disease Day; it is, after all, a rare day. Perhaps even more fitting is its absence, its silence, in three out of every four years. Most years, for most people, February 28 slides on into March 1 as though February 29 were never even a thing. Unless you are one of the rare people born on Leap Day (at around 4 million worldwide, they are a group only 1% the size of the rare disease population), you probably don’t give a second thought to that non-second of time at midnight in which February 29 doesn’t really exist.

Rare diseases often exist in silence, too. They live in the absences: the friend who stops coming to gatherings because the exhaustion from a late night might incapacitate her for days; the coworker who stops coming to the office because the pain is too much; the mother who doesn’t explain why her child is still in the hospital because she doesn’t know where to begin.

Unless you have been directly affected by one of them, it’s likely you’ve never heard of most or all of the nearly 7,000 rare diseases recognized by NORD. I had certainly never heard of gastroschisis or short bowel syndrome until they were quite literally thrust into my lap four years ago. But if you know even a handful of people, odds are high you know someone who has been affected by rare disease. By definition, each rare disease affects fewer than 200,000 people in the United States at any one time, but collectively there are more than 30 million people living with rare disease in the U.S. – that’s about 1 in 10 – and an estimated 350 million people worldwide.

This year’s RDD theme is research, and research is certainly a fundamental necessity for the rare disease community. Fewer than 5% of rare diseases currently have a treatment, and lack of knowledge and quality information can result in devastating delays in diagnosis. Many people remain undiagnosed, sometimes for entire lifetimes. And the need for treatments and cures is pressing; rare diseases are responsible for 35% of deaths in the first year of life, and 30% of children with rare diseases will not live to see their fifth birthday.

Last year’s theme, however, will always resonate most deeply with me: Patient Voice. On a true Leap Day in 2016, RDD made those 350 million voices heard. Research is brought about by advocacy and awareness, and advocacy and awareness begins with voices. The patient voice is the best advocate in a world where even most doctors don’t understand rare diseases, and it is the best avenue for placing faces next to scary, unpronounceable words. It’s voices that fill the absence; voices that inspire more voices; voices that make sure someday, somewhere, a mother will never feel as completely and utterly lost and alone as I felt in 2013.

To hear more voices or to learn more about rare disease, visit rarediseaseday.org or Rare Disease on The Mighty.

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