Outbreak of Eosinophilic Meningitis Associated With Drinking Raw Vegetable Juice in Southern Taiwan

Abstract

The most common cause of eosinophilic meningitis is the rat lungworm Angiostrongylus cantonensis a parasite that is endemic in the southeast Asian and Pacific regions. Outbreaks of eosinophilic meningitis associated with drinking raw vegetable juice are rarely reported, even in regions of endemic infection. We performed a cohort study among Taiwanese with eosinophilic meningitis who drank raw vegetable juice within three months of the onset of the outbreak. Clinical manifestations, laboratory examinations, and outcomes were prospectively followed. Five native Taiwanese met the case definition of eosinophilic meningitis. Specific antibodies to A. cantonensis were detected in the serum of five of the patients and in the cerebrospinal fluid (CSF) of four of the patients. Central nervous system manifestations included headache (n = 5 [100%]), Brudzinski's sign/stiff neck (n = 5 [100%]), hyperesthesia/paresthesias (n = 5 [100%]), and cranial nerve palsy (n = 1 [20%]). Laboratory findings included peripheral (n = 5 [100%]) and CSF eosinophilia (n = 4 [80%]), transient increases in the white blood cell count (n = 1 [20%]), and in serum levels of creatine kinase (n = 1 [20%]). Meningeal enhancement, as well as high signal intensity, at the subcortical white matter on T2 weighted and fluid attenuated inversion recovery images were observed on magnetic resonance imaging in four patients. There were three episodes of relapse during treatment and all resolved with after a lumbar puncture and/or administration of steroids. At the 12-month follow up, all five patients had recovered without neurologic sequelae. Risk factors identification showed that consumption of raw vegetable juice was associated with illness (Pearson correlation test r = 0.867, P = 0.01). There was association between the presence of raw vegetable juice and CSF eosinophilia (Spearman's correlation test r = 0.816, P = 0.004).

Eosinophilic Meningitis Attributable to Angiostrongylus cantonensis Infection in Hawaii: Clinical Characteristics and Potential Exposures

“…Other studies have reported infection from consuming undetected small slugs, snails, or planaria on produce (e.g., in a Caesar salad and raw vegetable juice). 5,10,11,28,34 Although we did not identify a point source for this outbreak, unintentional consumption of snails/slugs or larvae in homegrown produce likely occurred on the island of Hawaii; almost all case-patients there described consuming produce from their own (or a non-commercial) garden, usually unwashed. Environmental studies found A. cantonensis larvae in slugs in the yards of the infant with a parasitologically confirmed case and two case-patients who shared a household.…”

“…There have been few studies of potential sources of accidental or incidental exposure; presumptive transmission from food items contaminated with larvae (e.g., salad or juice containing snails, slugs, or larvae) has been reported. 5,10,11 After penetrating the gastrointestinal tract, the larvae spread hematogenously to the central nervous system. 12,13 Following an average incubation period of 1-3 weeks, symptomatic persons often develop headache, meningeal symptoms, and sensory abnormalities.…”

Update on Eosinophilic Meningoencephalitis and Its Clinical Relevance

“…Another source of infection can be other mollusks, and paratenic hosts, such as frogs, freshwater prawns, crabs, fish, and planaria. A less common path of infection is ingestion of contaminated vegetables, water, or fruit juice (262,280). Hands may carry the larvae directly to the mouth, after manipulation of or playing with mollusks, which is likely the main mode of infection among young children.…”

Encephalitis Caused by Angiostrongylus cantonensis after Eating Raw Frogs Mixed with Wine as a Health Supplement

“…There was usually a history of eating or playing with snails or slugs. Only three scattered outbreaks were found to have occurred during the past two decades caused by eating raw golden apple snails and drinking raw vegetable juice (10,11). Frogs and toads are known as paratenic hosts of A. cantonensis (12).…”