Neuro-angiostrongyliasis: unresolved issues

Spontaneous Shedding of Metastrongyloid Third-Stage Larvae by Experimentally Infected Limax maximus

“…Whether the same or similar results would have been found with A. vasorum or T. wilsoni L3 held under the same conditions is not known. Gastropod shedding of metastrongyloid L3 may be (as speculated) just an aberration of experimental infection models with no relevance to natural infection of these parasites (Ash 1976, Prociv et al 2000, Cowie 2013). Experimental infections tend to occur at higher levels than those generally found in gastropods under natural conditions (Kralka and Samuel, 1984).…”

“…Recently gastropod L3 shedding has also been reported for a crenosomatid (Troglostrongylus brevior) (Giannelli et al 2015). Detection of L3 in mucus of slugs and semi-slugs has been reported for A. cantonensis and A. costaricensis, although in small numbers and able to survive for only short periods of time outside the gastropod host, bringing into question what role it may play as a source of exposure in natural infections (Ash, 1976, Bonetti et al 1998, Cowie, 2013, Prociv et al 2000, Qvarnstrom et al 2007). L3 of A. cantonensis may also be released by land snails and slugs immersed in water suggesting that contaminated drinking water could be a potential route of exposure for human infection (Cheng and Alicata, 1964).…”

Prevalence and distribution of Angiostrongylus cantonensis (Nematoda, Angiostrongylidae) in Achatina fulica (Mollusca, Gastropoda) in Baixada Santista, São Paulo, Brazil

“…A. cantonensis has been observed in several regions of the world [3][4][5][6][7] , and they were distributed from Eastern Asia to other continents by two main hosts: rats (definitive hosts) and Achatina fulica Bowdich, 1822 (one of the intermediate hosts), especially during the Second World War 8 . Several species of land and freshwater snails have also been found to be naturally infected with A. cantonensis [9][10][11][12][13][14] .…”

“…In Brazil, the occurrence of A. cantonensis has been reported in all states except for Acre [9][10][11][12][13][14][15][16][17] . Man, being an accidental host, acquires parasitosis when eating foods contaminated with stagethree larvae (L3), raw or undercooked mollusks, and paratenic hosts such as shrimp, frogs, fish, and flatworms 4,[18][19][20] , as well as crabs and lizards 21,22 . In humans, these parasites migrate to the central nervous system (CNS), where they die in the meninges, causing inflammatory reactions 23 24 .…”

Zoonotic tissue parasites of Australian wildlife

“…system. This occurs in young children who deliberately or accidentally ingest snails or slugs containing infective larvae [5][6][7] , or foolish young adults who do so for a bet 8,9 .…”