Evaluation of terrestrial gastropods as possible intermediate hosts of Gurltia paralysans in southern Chile

Abstract

Gurltia paralysans is the causal agent of gurltiosis in domestic cats in South America. Although the life cycle of G. paralysans is unknown, it is thought that gastropods could act as intermediate hosts (IHs), as is the case for several nematodes in the Angiostrongylidae family. The aim of this study was to search for G. paralysans larvae in terrestrial gastropods and determine their role in the life cycle of this nematode species. Terrestrial gastropod samples (n=835) were collected in Punucapa, Valdivia, southern Chile, where cases of gurltiosis had been reported before. The samples included species from the families Arionidae, Limacidae, Helicidae and Milacidae. All gastropods were subjected to enzymatic digestion to isolate G. paralysans larvae. Ten percent of the gastropod samples were analyzed using seminested PCR targeting the 28S rRNA gene, while 2.6% were analyzed by histopathological examination. The results indicated the absence of G. paralysans when using any of the three methods. In conclusion, further studies are needed to evaluate specific species of aquatic or native gastropods acting as possible IHs (in this geographic location).

The Neglected Angio-Neurotrophic Parasite Gurltia paralysans (Nematoda: Angiostrongylidae): Northernmost South American Distribution, Current Knowledge, and Future Perspectives

“…Thus, confirmed gurltiosis cases have been reported in tropical, arid (dry), and temperate climates, showing a considerable climatic tolerance. Despite the natural gurltiosis distribution throughout South America, it is essential to note that southern Chile is a well-known gurltiosis hotspot where the main geographic distribution of gurltiosis cases in domestic cats occurs [22]. Meanwhile, the only reports of the disease in wild felids are parasitic myelopathy in a Brazilian margay [21] and the first Wolffhügel report of the disease's native host, the kodkod [20].…”

“…The nematode life cycle has not been fully elucidated but probably involves hypothesized paratenic hosts such as amphibians, birds, insects, lizards, and rodents, and invertebrate gastropod fauna as obligate intermediate hosts in which the larvae developmental process occurs from first-stage larvae (L1), second-stage larvae (L2), and final infective third-stage larvae (L3) (Figure 1), as is the case for several metastrongyloid parasites in the Angiostrongylidae family. An extensive survey to identify G. paralysans larval stages was conducted in terrestrial gastropods (n = 835) collected from a previous feline hotspot located in southern Chile (Valdivia) showed that neither semi-nested PCR, enzymatic digestion nor histopathological examination could identify the presence of G. paralysans larvae in mollusks of the families Arionidae, Limacidae, Helicidae, and Milacidae [22]. Therefore, the obligate intermediate hosts of this parasitic disease are still unknown, and the morphological traits of larvae have not been identified so far.…”

“…Adult male specimens of G. paralysans have a total body length of 12-18 mm and a width that varies from 72-103 μm to 26-32 μm anterior to the bursa and the cephalic region, respectively. Consistently larger female adults show a An extensive survey to identify G. paralysans larval stages was conducted in terrestrial gastropods (n = 835) collected from a previous feline hotspot located in southern Chile (Valdivia) showed that neither semi-nested PCR, enzymatic digestion nor histopathological examination could identify the presence of G. paralysans larvae in mollusks of the families Arionidae, Limacidae, Helicidae, and Milacidae [22]. Therefore, the obligate intermediate hosts of this parasitic disease are still unknown, and the morphological traits of larvae have not been identified so far.…”

Histological and Immunohistochemical Characterization of Vascular Alterations in Meninges of Cats Infected with Gurltia paralysans

“…Sepulveda-Garcia et al failed in demonstrating Gurltia sp. in various Pathogens 2022, 11, 88 2 of 7 gastropods from southern Chile [11]. Disease in domestic cats is dominated by paraparesis, paraplegia, hindlimb ataxia, hindlimb proprioceptive deficit, urinary incontinence, decrease superficial and/or deep pain sensation in the hindlimbs, tail and anal atony with a slow clinical course of many months to two years [2,3,[5][6][7].…”

A Molecular Survey on Neglected Gurltia paralysans and Aelurostrongylus abstrusus Infections in Domestic Cats (Felis catus) from Southern Chile

“…The life cycle of G. paralysans is currently unknown, but it has been suggested to have an indirect cycle as occurs for other closely related nematodes of the Angiostrongylidae family [ 1 , 6 ]. Therefore, it has been proposed that terrestrial gastropods (snails and slugs) could act as obligate intermediate hosts (IH), and multiple rodents, insects, reptiles, amphibians, and/or birds participate as paratenic hosts (PH) [ 6 , 7 ]. Clinical signs of feline gurltiosis normally include chronic or asymmetric ataxia of the pelvic limbs, ambulatory paraparesis, unilateral and bilateral hyperactive patellar reflexes, proprioceptive deficits, weight loss, constipation, and urinary and fecal incontinence.…”