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As you get more involved with IDF and the primary immunodeficiency (PI) community, you may hear the expression, "THINK ZEBRA!" Or maybe you've seen a group of volunteers decked out in zebra-striped gear. If you’re curious about the meaning, we’ve got you covered.

Where does the term come from? 

A common phrase for up-and-coming doctors to learn in medical school is, “When you hear hoof beats, think of horses, not zebras.” This is generally good advice to focus on the most likely diagnoses, rather than the least likely. But sometimes a doctor needs to think of zebras—or rare diseases like PI. People with PI are the zebras of the medical world.

What does it mean to THINK ZEBRA? 

Original Think Zebra Logo

THINK ZEBRA! expresses how people with PI are just as strong, resilient, and awe-inspiring as zebras themselves. So join the movement, put on your favorite zebra attire, and start spreading the word about the amazing individuals in the PI community. 

People with PI and their families and friends often wear zebra-striped clothes and accessories, which has become a popular way for all ages to identify with zebras. It’s also a great way for children with PI to describe their condition to others.

Who’s TZ the Zebra?

Hold onto your stripes, folks, because IDF brings the THINK ZEBRA! motto to life with the one and only TZ the IDF Zebra. And yes, TZ stands for THINK ZEBRA! 

As the IDF mascot, TZ travels the country spreading awareness for PI, meeting other zebras, and making everyone from kids to grown-ups grin from ear to ear—reminding them that in this community, we're all #zebrastrong.