American teenager Trent Soderlund was dozing on the beach near Batu Karas, Indonesia, when it struck. He sat bolt upright, propelled by sharp pains just below his ribcage. Trent tried to relax, slowed his breathing—nothing helped. He stood, and the cramping moved lower, rolling and rumbling, audibly, violently. If I can just make it to a bathroom…

Barefoot and shirtless, Trent managed a stiff-legged walk to the beach road where he spotted a cluster of small wooden huts—some labeled Kamar Kecil, others Musholla. He stared for a few precious seconds, but his pain-addled mind couldn’t remember which word meant toilet…and which designated a small Muslim prayer room. He chose Musholla, a mistake that may have cost him his life.