A primary amoebic meningoencephalitis case associated with swimming in seawater.

This case report describes a 62-year-old male fisherman who presented with persistent vomiting, headache, and behavior changes. Despite initial antibiotic and corticosteroid treatment, his condition worsened, leading to coma and subsequent death. Macro-genome sequencing of cerebrospinal fluid (CSF) revealed the presence of Naegleria fowleri infection, which had been missed during initial laboratory tests. The patient's exposure history included sea-swimming near Zhoushan Island.