Over the past 30 years, the raccoon-associated roundworm Baylisascaris procyonis has emerged as an uncommon but noteworthy human pathogen associated with devastating eosinophilic meningoencephalitis
in 25 patients (1-4).
Hemorrhagic necrotizing eosinophilic meningoencephalitis
associated with large numbers of intact larvae has been described in patients with fatal cases (1,4), and all but 1 patient who survived (9) were left with severe neurologic deficits (1,4-6).
Because of eosinophilic meningoencephalitis
, thorough analyses were conducted for immunologic and infectious etiologies.
To the Editor: The nematode Angiostrongylus cantonensis (rat lung worm), a zoonotic parasite that can accidentally infect humans and cause eosinophilic meningoencephalitis
, has the Norway rat (Rattus norvegicus) as one of its most frequent definitive vertebrate hosts (1).