First record of natural infection by Angiostrongylus cantonensis (Nematoda: Metastrongyloidea) in Belocaulus willibaldoi and Rattus norvegicus in an urban area of São Paulo city, SP, Brazil

Abstract

Angiostrongylus cantonensis , a rat lungworm, is one of the leading causes of eosinophilic meningitis in humans. Infection in humans occurs by the ingestion of intermediate hosts, undercooked paratenic hosts or contaminated vegetables and fruits by mucus from infected molluscs. This zoonosis is widespread in tropical and subtropical areas of Southeast Asia, it has also been reported in the Pacific Islands as well as in other regions of Americas. In Brazil, human cases of angiostrongyliasis have been reported since 2007 in Southeast, Northeast, and South regions. In January 2011, we collected a batch of 30 Belocaulus willibaldoi slides in a neighborhood of São Paulo city (Parque Fernanda). Six of them were used for identifying species, and the others (24) were used in parasitological tests through digestion in peptic solution and then larvae isolation by the Rugai method. A total of 250 larvae were obtained and they had morphological traits of Angiostrongy lus spp. Later, four Golden hamsters ( Mesocricetus auratus ) were infected with 38 larvae that allowed the recovery of young worms from the brain and lungs of rodents on the 21 st and 30 th day of infection. In this same neighborhood we captured rodents ( Rattus norvegicus ) that, after necropsy led us to recovery of 22 adult worms in the pulmonary arteries (14 males and 8 females) in May 2011. The larvae and worms obtained from natural infection were evaluated by morphological and morphometric parameters, as well as biological behavior patterns and molecular profile. All methodologies identified the parasite as Angiostrongylus cantonensis . In this way, we report for the first time, the natural infection by A. cantonensis in intermediate ( B. willibaldoi ) and definitive ( R. norvegicus ) hosts in a new urban region of Brazil.

Susceptibility of Angiostrongylus cantonensis Larvae to Anthelmintic Drugs

“…A. cantonensis first-stage larvae (L1), kindly provided by Adolfo Lutz Institute (São Paulo, SP, Brazil), were isolated from Wistar rats (Rattus novergicus) feces according to Rugai's traditional method ( da Mota et al, 2020 ). Briefly, fecal samples collected two months after infection were suspended in RPMI 1640 medium containing 1% (v/v) penicillin/streptomycin solution and centrifuged at 300 x g for 4 min.…”

Immunoanalysis of different antigenic preparations of Angiostrongylus cantonensis for neuroangiostrongyliasis diagnosis improvement

“…Obtainment of larvae and worms of A. cantonensis - Specimens were obtained from the cycle of A. cantonensis , strain Village, 26 maintained by Enteroparasite Nucleus of IAL, in which groups of 15 snails of Biomphalaria glabrata species (BH strain) and three Wistar rats provided by the Institute of Tropical Medicine (IMT) were used. The procedures adopted for maintenance of parasite consisted of infection of molluscs with approximately 700 L1, via opening of shells, based on modifications of methodology adopted by Yousif and Lämmler.…”

“…The sera tested in this study were sent to the collaborating center "Pontifical Catholic University of Rio Grande do Sul, Brazil", which was responsible for the laboratory diagnosis of angiostrongyliasis in Brazil, that include ELISA and Western blot using heterologous antigen of young female worm. (25) Obtainment of larvae and worms of A. cantonensis -Specimens were obtained from the cycle of A. cantonensis, strain Village, (26) maintained by Enteroparasite Nucleus of IAL, in which groups of 15 snails of Biomphalaria glabrata species (BH strain) and three Wistar rats provided by the Institute of Tropical Medicine (IMT) were used. The procedures adopted for maintenance of parasite consisted of infection of molluscs with approximately 700 L1, via opening of shells, based on modifications of methodology adopted by Yousif and Lämmler.…”

Detecção de antígenos em cortes parafinados de vermes e caramujos infectados por Angiostrongylus cantonensis pela reação de imunofluorescência

“…The isolate was identified by morphological, biological and molecular criteria by the NE/ IAL and by the Laboratório de Biologia Molecular de Parasitos e Fungos, of Centro de Parasitologia e Micologia of IAL. The strain was registered in the collection as Village 10 .…”

“…Despite this, the parasitosis is still unknown by most health professionals, which may explain the low frequency of cases in the country 7 . On the other hand, reports of the parasite presence in definitive and intermediate hosts are increasing, demonstrating that it is an emerging zoonosis with a potential risk of expansion in Brazil 10,11 .…”