The last-resort antibiotic was found in Borneo jungle soil

Scientists at Eli Lilly isolated a new antibiotic-producing bacterium from that sample and found it could kill bacteria that other antibiotics of the era could not touch, including early resistant staph infections.

The organism, later classified as Amycolatopsis orientalis, produced a compound the company named vancomycin, first isolated in 1953 and described in the scientific literature by 1955. It worked against stubborn gram-positive infections but was initially set aside as newer antibiotics with fewer side effects reached the market.

Vancomycin returned to prominence decades later, once methicillin-resistant Staphylococcus aureus and antibiotic-associated colitis made its narrow, reliable activity valuable again, and it became a drug doctors reach for when other antibiotics have already failed. It remains in that last-resort role today, now joined by newer drugs developed in part because of resistance vancomycin itself eventually faced.

A missionary's soil sample, now a hospital's last option.