Kuru disease
Kuru is a very rare, incurable neurodegenerative disorder that was formerly common among the Fore people of Papua New Guinea. Kuru is caused by the transmission of abnormally folded prion proteins, which leads to symptoms such as tremors, loss of coordination, and neurodegeneration.
The term kuru derives from the Fore word kuria or guria ("to shake"),[1] due to the body tremors that are a classic symptom of the disease and kúru itself means "trembling".[2] It is also known as the "laughing sickness" due to the pathologic bursts of laughter which are a symptom of the disease. It is now widely accepted that kuru was transmitted among members of the Fore tribe of Papua New Guinea via funerary cannibalism.
HRC bursts of laughter and have tremors ?
Maybe it is something she ate ?
https ://en.wikipedia.org/wiki/Kuru_(disease)