Angiostrongylus cantonensis Meningo-Encephalitis in Children—Heightened Awareness Needed During Prolonged Wet Weather Conditions

Abstract

Aim

Angiostrongylus cantonensis, the leading cause of eosinophilic meningoencephalitis, is well established in eastern Australia. Prolonged wet weather in Queensland during 2021–2022 coincided with anecdotal reports of increased neuroangiostrongyliasis cases, prompting an evaluation of paediatric cases from 2013 to 2022.

Methods

This retrospective observational study reviewed children (0–16 years) with cerebrospinal fluid (CSF) eosinophilia (≥ 10% of the total CSF leukocyte count) and/or A. cantonensis testing (serology or polymerase chain reaction) between 01/01/2013 and 31/12/2022, using statewide laboratory data and patient records.

Results

Eighty children were identified: 59 (74%) had CSF eosinophilia without A. cantonensis testing, 9 (11%) had CSF eosinophilia with A. cantonensis testing, and 12 (15%) had A. cantonensis testing without CSF eosinophilia. Neuroangiostrongyliasis was either proven or probable in seven children: five (71%) during 2021–2022, coinciding with prolonged wet weather. A significant positive correlation was observed between rainfall and case numbers (r = 0.88, p < 0.01). Median age of diagnosed children was 4 years (IQR 1.8–8.5, range 1.5–13 years) and five (71%) were male. Snail or slug exposure was reported in four (57%) children. All children presented with vomiting, and six also had a headache and focal neurology (86%). Abnormal neuroimaging was noted in six (86%) cases. Five children received corticosteroid therapy alone (71%), while two (29%) were managed conservatively. There were no deaths, but one child had persistent focal neurological abnormalities at discharge.

Conclusion

Awareness of A. cantonensis and exposure risks is crucial, especially during prolonged wet weather conditions. While most children in this study had good outcomes, this is not always the case.