Monica Ammon Fernandez

Rapid spread of an invasive snail in South America: the giant African snail, Achatina fulica, in Brasil

Beginning around 1800, but primarily since the early and mid-twentieth century, the giant African snail, Achatina (Lissachatina) fulica Bowdich, 1822, has been introduced throughout the tropics and subtropics and has been considered the most important snail pest in these regions. In Brasil, specimens probably brought from Indonesia were introduced into the state of Paraná in the 1980s for commercial purposes (“escargot” farming) that were not successful. Achatina fulica is now widespread in at least 23 out of 26 Brasilian states and the Federal District, including the Amazonian region and natural reserves. Among the reasons for the species’ rapid invasion are its high reproductive capacity and the tendency for people to release the snails into the wild. Achatina fulica occurs in dense populations in urban areas where it is a pest in ornamental gardens, vegetable gardens, and small-scale agriculture. Also of concern is the damage caused to the environment, and potential competition with native terrestrial mollusks. It can also act as an intermediate host of Angiostrongylus cantonensis, a nematode that can cause meningoencephalitis in people, and it may be a potential host of A. costaricensis, which causes abdominal angiostrongylosis, a zoonosis that occurs from the southern United States to northern Argentina. Management and control measures for A. fulica are under way in Brasil through a national plan implemented by the Brasilian government.

The giant African snail Achatina fulica as natural intermediate host of Angiostrongylus cantonensis in Pernambuco, northeast Brazil

The human cases of eosinophilic meningitis recently reported from Brazil have focused the attention of the public health agencies on the role the introduced snail Achatina fulica plays as hosts of the metastrongylid nematodes. Determining the potential of this snail to host and develop infective larval stages of metastrongylids in the wild and identify the species harbored by them is crucial for designing effective control measures. Here we assess if A. fulica may act as intermediate host of A. cantonensis at the peridomiciliary areas of a patients house from state of Pernambuco (PE), who was diagnosed with eosinophilic meningitis and a history of ingesting raw molluscs. Larvae obtained from naturally infected A. fulica were orally administered to Rattus norvegicus. The worms were collected from the pulmonary artery and brain, and were morphologically characterized and compared to the Japan isolate of A. cantonensis. Adult worms and infective L(3) larvae (PE isolate) recovered from A. fulica specimens were also analyzed by polymerase chain reaction and restriction fragment length polymorphism of ITS2 region from rDNA and compared to A. cantonensis (ES isolate), A. vasorum (MG isolate) and A. costaricensis (RS isolate). The large size of the spicules (greater than those observed in other species of Angiostrongylus) and the pattern of the bursal rays agree with the original species description by Chen (1935). Furthermore, the morphology of the PE isolate was similar to that of Japan isolate. The PCR-RFLP profiles obtained were distinctive among species and no variation in patterns was detected among adult individuals from A. cantonensis isolates from PE and ES. The importance of A. fulica as an intermediate host of eosinophilic menigoencepahlitis in Brazil is emphasized.

Freshwater snails and schistosomiasis mansoni in the state of Rio de Janeiro, Brazil: V -- Norte Fluminense Mesoregion.

In this paper, the fifth of a series dealing with the survey of freshwater gastropods of the state of Rio de Janeiro, the results of collections carried out in the Norte Fluminense Mesoregion from 2002 to 2003 are presented and revealed the occurrence of 19 species: Antillorbis nordestensis; Burnupia sp.; Biomphalaria tenagophila; Drepanotrema anatinum; Drepanotrema cimex; Drepanotrema depressissimum; Drepanotrema lucidum; Ferrissia sp.; Gundlachia ticaga; Gundlachia sp.; Heleobia sp.; Hebetancylus moricandi; Idiopyrgus sp.; Lymnaea columella; Melanoides tuberculatus; Physa acuta; Physa marmorata; Pomacea sordida, and Pomacea sp. Concerning the snail hosts of Schistosoma mansoni only B. tenagophila was found, in contrast with other previuosly studied mesoregions.No specimens were found harbouring larval forms of S. mansoni although different kinds of cercariae had been observed. An account about the current schistosomiasis transmission sites in this Mesoregion is presented as well.In order to elaborate a planorbid chart of the State of Rio de Janeiro a survey of freshwater gastropods in the Metropolitan Mesoregion of this State was performed and revealed the occurrence of 20 species: Antillorbis nordestensis (Lucena, 1954); Biomphalaria glabrata (Say, 1818); Biomphalaria schrammi (Crosse, 1864); Biomphalaria straminea (Dunker, 1848); Biomphalaria tenagophila (Orbigny, 1835); Burnupia sp.; Drepanotrema anatinum (Orbigny, 1835); Drepanotrema cimex (Moricand, 1839); Drepanotrema lucidum (Pfeiffer, 1839); Ferrissia sp.; Gundlachia ticaga (Marcus & Marcus, 1962); Heleobia davisi Silva & Thomé, 1985; Lymnaea columella Say, 1817; Melanoides tuberculatus (Müller, 1774); Physa cubensis Pfeiffer, 1839; Physa marmorata Guilding, 1828; Pomacea sp.; Pomacea canaliculata (Lamarck, 1822); Pomacea lineata (Spix, 1827) and Pomacea sordida (Swainson, 1823). Among the planorbid species B. tenagophila was the most frequent, occurring in all municipalities surveyed. The present study extends the distribution of B. straminea in the State of Rio de Janeiro and reports new records for A. nordestensis, B. schrammi, G. ticaga, H. davisi and the genera Burnupia and Ferrissia. An account about the current transmission areas of schistosomiasis mansoni in this Mesoregion is presented as well.

First report of Angiostrongylus cantonensis (Nematoda: Metastrongylidae) in Achatina fulica (Mollusca: Gastropoda) from Southeast and South Brazil

The rat lungworm Angiostrongylus cantonensis is a worldwide-distributed zoonotic nematode that can cause human eosinophilic meningoencephalitis. Here, for the first time, we report the isolation of A. cantonensis from Achatina fulica from two Brazilian states: Rio de Janeiro (specifically the municipalities of Barra do Piraí, situated at the Paraiba River Valley region and São Gonçalo, situated at the edge of Guanabara Bay) and Santa Catarina (in municipality of Joinville). The lungworms were identified by comparing morphological and morphometrical data obtained from adult worms to values obtained from experimental infections of A. cantonensis from Pernambuco, Brazil, and Akita, Japan. Only a few minor morphological differences that were determined to represent intra-specific variation were observed. This report of A. cantonensis in South and Southeast Brazil, together with the recent report of the zoonosis and parasite-infected molluscs in Northeast Brazil, provide evidence of the wide distribution of A. cantonensis in the country. The need for efforts to better understand the role of A. fulica in the transmission of meningoencephalitis in Brazil and the surveillance of molluscs and rodents, particularly in ports, is emphasized.

Eosinophilic meningitis caused by Angiostrongylus cantonensis: an emergent disease in Brazil.

Eosinophilic meningitis (EoM) is an acute disease that affects the central nervous system. It is primarily caused by infection with the nematode Angiostrongylus cantonensis. This infection was previously restricted to certain Asian countries and the Pacific Islands, but it was first reported in Brazil in 2007. Since then, intermediate and definitive hosts infected with A. cantonensis have been identified within the urban areas of many states in Brazil, including those in the northern, northeastern, southeastern and southern regions. The goals of this review are to draw the attention of the medical community and health centres to the emergence of EoM in Brazil, to compile information about several aspects of the human infection and mode of transmission and to provide a short protocol of procedures for the diagnosis of this disease.

Freshwater snails and Schistosomiasis mansoni in the state of Rio de Janeiro, Brazil: III - Baixadas Mesoregion

In this paper, the third of a series dealing with the survey of freshwater gastropods of the state of Rio de Janeiro, the results of collections carried out in the Mesoregion Baixadas from 2000 to 2002 are presented. Twenty-two species, belonging to seven families, were found. As to the snail intermediate hosts of Schistosoma mansoni, the most frequent species was Biomphalaria tenagophila besides some new findings of Biomphalaria straminea. No specimens were found harboring larval forms of S. mansoni although different kinds of cercariae had been observed.

Susceptibility of Biomphalaria straminea (Dunker, 1848) from Serra da Mesa Dam, Goiás, Brazil to infection with three strains of Schistosoma mansoni Sambon, 1907

Ecological changes from water resources development projects often affect the epidemiology of water-associated diseases. In order to investigate the occurrence and distribution of freshwater snails of medical and veterinary importance in the area of influence of the Serra da Mesa Hydroelectric a survey has been performed since 1997 and revealed the occurrence of well-established populations of Biomphalaria straminea (Dunker, 1848) in the 8 municipalities surrounding the lake. Areas of epidemiologic risk for schistosomiasis were selected and studies of parasite-mollusc compatibility were undertaken using specimens from 19 populations of B. straminea and 3 strains (CM, EC and PB) originally isolated from B. straminea. Among 1,135 specimens used 15 became infected (infection index of 1.3%) and 8 populations were susceptible to the schistosome strains: B. straminea from Campinorte (Castelão, susceptible to CM and EC strains, and Planeta Agua, EC strain), Colinas (Tocantinzinho river, CM and EC strains), Minaçu (Canabrava river, EC strain), Niquelândia (Codemin, CM and PB strains, and Almas river, CM strain), Uruaçu (touristic area, PB strain) and Santa Rita do Novo Destino (Maranhão river, CM and EC strains). These results, associated with marked social and ecological changes occurred, strongly suggest the possibility of B. straminea coming to act as a vector of schistosomiasis in the studied area.

A survey of freshwater gastropods in the Microrregião Serrana of the State of Rio de Janeiro, Brazil

In 1984 we received samples of freshwater gas-tropods from many localities of the State of Rio deJaneiro, sent by Fundacao Nacional de Saude foridentification. In the past three years, aiming toelaborate a chart of planorbids of the State of Riode Janeiro additional collecting was done by theauthors in the area corresponding to theMicrorregiao Serrana of the state: Petropolis,Teresopolis and Sao Jose do Vale do Rio Preto.The survey was extended to the neighbour towns,Guapimirim and Mage, in order to improve theknowledge of that poorly studied area.The molluscs were collected from differentsuitable snail habitats: streams, rivers and marshareas in the Atlantic forest as well as drainage andsewage ditches, wells, flood areas, ponds and irri-gation canals.Live snails were kept at the laboratory for amonth in aquaria containing dechlorinated tapwater and, at the bottom, a thin layer of a 2:1 mix-ture of screened reddish soil and ground oystershells as a source of mineral nutrients. Snails werefed on fresh lettuce leaves. In the meantime speci-mens of Biomphalaria were exposed to artificiallight in intervals of five days to determine possibleinfection with trematode larvae, mainly Schisto-soma mansoni cercariae. The ten larger snails ofeach sample were preserved in Railliet-Henry’sfluid after relaxation in a 0.05% nembutal solutionand two of them were dissected under stereomi-croscope for identification. Technical details weredescribed elsewhere (SC Thiengo 1995 TecnicasMalacologicas, p. 255-265. In FS Barbosa, Topicosem Malacologia Medica , Fiocruz, Rio de Janeiro).Samples of taxonomic importance were depositedat the Malacological Collection of InstitutoOswaldo Cruz/Fiocruz.In all, 7 species of planorbids and 10 speciesof other freshwater gastropods were found in 15localities at the studied area (Table): Antillorbisnordestensis (Lucena, 1954); Biomphalariaperegrina (Orbigny, 1835); Biomphalaria stra-minea (Dunker, 1848); Biomphalaria tenagophila(Orbigny, 1835); Drepanotrema anatinum(Orbigny, 1835); Drepanotrema cimex (Moricand,1839); Drepanotrema lucidum (Pfeiffer, 1839);Ferrissia sp.; Gundlachia moricandi (Orbigny,1837); Heleobia davisi Silva & Thome, 1985; Lym-naea columella (Say, 1817); Lymnaea sp.;Melanoides tuberculata (Muller, 1774); Physacubensis Pfeiffer, 1839; Physa marmorataGuilding, 1828; Pomacea canaliculata (Lamarck,1801); Pomacea sordida (Swainson, 1823).Among the planorbid species B. tenagophilawas the most frequent, occurring in 13 out of the15 localities surveyed. According to WL Paraense(1986 Distribuicao dos caramujos no Brasil, p. 117-128. In FA Reis, I Faria & N Katz (eds), ModernosConhecimentos sobre Esquistossomose Man-sonica, Biblioteca da Academia Mineira deMedicina, Belo Horizonte) it ranges from Caravelas(17

Susceptibility of Biomphalaria amazonica and Biomphalaria occidentalis from Manso Dam, Mato Grosso, Brazil to infection with three strains of Schistosoma mansoni

As well as malaria and yellow fever, schistosomiasis is one of the main endemic diseases associated to environments which suffered some impact related to the development of great economic projects, as for example the construction of hydroelectric power stations. Aiming to investigate the occurrence and distribution of freshwater snails of medical and veterinary importance in the area which suffered impact from the Manso hydroelectric power station a survey was performed during the period of 2002 to 2003 and revealed the occurrence of populations of Biomphalaria amazonica and Biomphalaria occidentalis. Studies on parasite-mollusc compatibility were undertaken using five B. amazonica colonies (Barão de Melgaço, Poconé, Santo Antônio do Leverger, and Chapada dos Guimarães, in the Manso and Casca rivers), and four B. occidentalis colonies (Cuiabá, Santo Antônio do Leverger, and Chapada dos Guimarães, in the Agua Fria district and Casca river) were exposed to miracidia of Schistosoma mansoni. Of 257 snails of B. amazonica used, 17 became infected (infection index of 6.61%) and all specimens of B. occidentalis proved unsusceptible. According to the strains used, of the 158 snails exposed to BH miracidia, 6 became infected (3.79%); of the 44 exposed to SJ miracidia, 6 became infected (13.63%); and of the 55 snails of B. amazonica exposed to EC miracidia, 5 became infected (9.09%). These results point out the low possibility of introduction of schistosomiasis in those areas, but we believe it can not be discarded as due the presence of B. amazonica.

Gastrópodes límnicos do Campus de Manguinhos, Fundação Oswaldo Cruz, Rio de Janeiro, RJ

A survey of freshwater gastropods of the Campus of Manguinhos, Fundação Oswaldo Cruz, Rio de Janeiro, was carried out during the last two years aiming to compare the current species with those found at the beginning of this century. Among 18 breeding sites in 880,000m2 of the surveyed area, 13 showed the following species: Antillorbis nordestensis; Biomphalaria glabrata; Biomphalaria straminea; Lymnaea columella; Melanoides tuberculatus; Physa cubensis; Pomacea glauca and Pomacea lineata. Notably, Biomphalaria tenagophila reported by Lutz in 1918, had disappeared and B. straminea and the Asiatic thiarid M. tuberculatus had been introduced. No specimens infected with Schistosoma mansoni were found.