# Hidden threats in urban environments: Angiostrongylus cantonensis in Banda Aceh’s cityscape

## TL;DR

This study finds the rat lungworm parasite in urban land snails in Banda Aceh, Indonesia, highlighting a potential public health concern.

## Contribution

The first molecular confirmation of Angiostrongylus cantonensis in Banda Aceh, Sumatra, Indonesia.

## Key findings

- 13.4% of Achatina (Lissachatina) fulica snails tested positive for A. cantonensis DNA in urban areas.
- No freshwater snails sold in wet markets tested positive for the parasite.
- ITS1 sequences from positive samples confirmed 100% identity with A. cantonensis.

## Abstract

Angiostrongylus cantonensis is a mollusk-borne parasitic nematode originating in Southeast Asia. Commonly known as the rat lungworm, it uses rats as definitive hosts, though other mammals, including humans, can be infected and typically suffer from neurological disorders. This study focuses on the parasite’s presence in its gastropod intermediate hosts in several urban and rural areas in Aceh province, Sumatra, Indonesia. Samples of Achatina (Lissachatina) fulica (161) and Pomacea sp. (90) were collected in eight localities in Banda Aceh. Additionally, 531 edible freshwater snails belonging to the genus Sulcospira sp. from three different localities in Aceh province were obtained in wet markets. All samples were examined by LAMP and qPCR for the A. cantonensis DNA. No samples of Sulcospira sp. and Pomacea sp. tested positive. 13.4% of L. fulica tested positive, with the highest prevalence in urban areas of Banda Aceh. The ITS1 sequences obtained from positive samples using conventional PCR confirmed 100% identity with A. cantonensis. The present study confirms, for the first time, the presence of the zoonotic parasite A. cantonensis in Banda Aceh, Sumatra, Indonesia. Notably, the handling and consumption of snails sold at wet markets do not appear to increase the risk of eosinophilic meningitis in this region. However, the relatively high prevalence of A. cantonensis in urban land snails underscores the need for continued vigilance and public health awareness.

Angiostrongylus cantonensis, commonly known as rat lungworm, is a parasitic nematode that can cause serious neurological disease in humans and other accidental hosts. It is transmitted via snail or slug intermediate hosts, typically through accidental ingestion of infected snails or contaminated produce. In this study, we investigated the presence of A. cantonensis in land and freshwater snails from urban and rural areas of Aceh province, Sumatra, Indonesia — region where its occurrence had not previously been documented. We tested over 780 snails using molecular diagnostic techniques and found that Achatina (Lissachatina) fulica, an invasive land snail commonly found in urban environments, had a relatively high infection rate. In contrast, none of the freshwater snails sold for consumption at local wet markets tested positive. Our findings represent the first molecular confirmation of A. cantonensis in Banda Aceh. While current practices around the handling and consumption of freshwater snails may pose little risk in this area, the presence of the parasite in urban land snails highlights the importance of public health awareness and monitoring, especially in densely populated settings where contact with infected snails is more likely.