The world's deadliest disease is one you rarely hear about nowadays. Many diseases affect millions of people every day, and while their fatality rates may have dropped, there's one that remains incredibly deadly: "laughing death."
Kuru is a rare, devastating disease first identified in the 1950s among the cannibal tribes of Papua New Guinea. In the Fore tribe's language, "Kuru" means both "trembling" and "deterioration."
MediGoo explains that this disease is caused by abnormally folded prion proteins. Its main symptoms include loss of coordination and tremors.
It earned the nickname "laughing death" because some of its victims exhibited peculiar smiles, while others had uncontrollable fits of laughter.
The disease spread through cannibalistic funeral rituals, where the Fore people believed they could gain intelligence and other attributes from the deceased person.
The cannibalistic ritual that led to Kuru disease was mainly performed by women and children, which is why the disorder was more prevalent in them. Men typically consumed muscle tissue instead.
Kuru could also spread if someone with the disease had an open wound, as mentioned by Healthline.
Although the practice of eating brains ceased in the 1960s, cases of Kuru continued to emerge in the following years, resulting in fatalities.
The incubation period for this disorder can be incredibly long, ranging from a few years to several decades. However, once symptoms appear, individuals typically have just a year or two to live.
Kuru progresses in three stages. The first stage is marked by headaches and joint pain. In the second stage, individuals become unable to walk, experiencing tremors and involuntary jerks.
In the final stage, speech becomes impossible, and dementia sets in. Around this time, eating and swallowing become increasingly difficult.
Kuru has no known cure, and it is fatal, usually lasting about a year.
Since 2010, no deaths from Kuru disease have been reported, and information about the last person to succumb to the disorder remains uncertain. Some reports suggest the last death occurred in 2005, while others claim it was in 2009.