It’s caused by microscopic nematodes that may be native; however, scientists remain unsure.

Source: https://countryfolks.com/scouting-can-save-forests/

"It's more than just controlling nematodes on a yam, it's about growing a sustainable infrastructure where people are going to be better off than they were before the wrap-and-plant technology came along," Opperman said.

Source: https://phys.org/news/2023-02-yams-benefit-banana-paper-cocoon.html

There, krill — small crustaceans that form the basis of the ocean food chain — eat them and become infected with larval stages of the nematodes.

Source: https://www.salon.com/2023/04/18/how-to-be-smart-when-it-comes-to-ordering-cooking-and-eating-raw-fish--_partner/

These nematodes, also known as roundworms, are incredibly common in our world today, thriving in various environments such as soil, water, and the ocean floor.

Source: https://greekreporter.com/2023/07/28/roundworm-revived-siberian-permafrost/