In Colombia in 2013, a man showed up to a hospital with a confusing array of symptoms. He was gaunt, having lost a lot of weight in the past few months. He was HIV-positive and hadn't been taking his medication. He was fatigued, with a fever and a cough. Stool samples revealed that he was carrying the parasite Hymenolepis nana, a common type of tapeworm; strangely, a scan showed cancer-like nodes in his lungs and lymph nodes.