Could the acute strongyloides venezuelensis infection cause non-reversible host morphological changes? / A infecção aguda por strongyloides venezuelensis pode causar alterações morfológicas irreversíveis no hospedeiro? / ¿Puede la infección aguda por las strongyloides venezuelensis causar cambios morfológicos irreversibles en el hostal?

Although research has investigated the host-parasite relationship in Strongyloides venezuelensis infection in the scope of its immunological implications, the morphological consequences of this response for the host organism are yet to be explored. Our objective was to perform an organ morphometric analysis in Wistar rats infected with the intestinal parasite Strongyloides venezuelensis compared with infected rats treated with ivermectin. Twenty-six animals composed three groups: control (non-infected), infected (infected with 2,000 Strongyloides venezuelensis larvae), and infected treated (infected with 2,000 Strongyloides venezuelensis larvae and treated with ivermectin). All rodents were killed 21 days after infection and morphometric analysis of different organs was performed. The results showed significantly higher body and fecal weight in the infected-treated group. The weight of the small intestine increased considerably in the infected group and decreased in the infected-treated group. Pancreas, right kidney, and heart volume increased in the infected group compared with the control group. Despite treatment, the volumes of the stomach, brain, and left kidney increased in both the infected groups compared with the control group indicating the possibility of non- reversible host morphological adaptations. S. venezuelensis infection can augment both, volume and weight of organs ­ not necessarily related to the Strongyloides expulsion process ­ even if the acute infection had been in remission. A potential explanation for these host adaptations, including the occurrence of organ plasticity, are briefly discussed. The following steps encompass a histological analysis to verify the occurrence of hypertrophy/hyperplasia and observe if such morphological alterations remain after infection.

Embora pesquisas tenham investigado a relação parasita-hospedeiro na infecção por Strongyloides venezuelensis no âmbito de suas implicações imunológicas, as consequências morfológicas dessa resposta para o organismo hospedeiro ainda precisam ser exploradas. Nosso objetivo foi realizar uma análise morfométrica de órgãos em ratos Wistar infectados com o parasito intestinal Strongyloides venezuelensis em comparação com ratos infectados tratados com ivermectina. Vinte e seis animais compuseram três grupos: controle (não infectados), infectados (infectados com 2.000 larvas de Strongyloides venezuelensis) e tratados infectados (infectados com 2.000 larvas de Strongyloides venezuelensis e tratados com ivermectina). Todos os roedores foram sacrificados 21 dias após a infecção e a análise morfométrica de diferentes órgãos foi realizada. Os resultados mostraram peso corporal e fecal significativamente maior no grupo tratado infectado. O peso do intestino delgado aumentou consideravelmente no grupo infectado e diminuiu no grupo infectado tratado. O volume do pâncreas, rim direito e coração aumentou no grupo infectado em comparação com o grupo controle. Apesar do tratamento, os volumes do estômago, cérebro e rim esquerdo aumentaram em ambos os grupos infectados em comparação com o grupo controle, indicando a possibilidade de adaptações morfológicas não reversíveis do hospedeiro. A infecção por S. venezuelensis pode aumentar tanto o volume quanto o peso dos órgãos ­ não necessariamente relacionado ao processo de expulsão de Strongyloides ­ mesmo que a infecção aguda estivesse em remissão. Uma possível explicação para essas adaptações do hospedeiro, incluindo a ocorrência de plasticidade de órgãos, é brevemente discutida. As etapas a seguir compreendem uma análise histológica para verificar a ocorrência de hipertrofia/hiperplasia e observar se tais alterações morfológicas permanecem após a infecção.

Aunque la investigación ha investigado la relación parásito-huésped en la infección con Strongyloides venezuelensis dentro del alcance de sus implicaciones inmunológicas, aún deben explorarse las consecuencias morfológicas de esta respuesta para el organismo huésped. Nuestro objetivo fue realizar un análisis morfométrico de órganos en ratas Wistar infectadas con el parásito intestinal Strongyloides venezuelensis en comparación con ratas infectadas tratadas con ivermectina. Veintiséis animales conformaron tres grupos: control (no infectado), infectados (infectados con 2.000 larvas de Strongyloides venezuelensis) y tratados infectados (infectados con 2.000 larvas de Strongyloides venezuelensis y tratados con ivermectina). Todos los roedores fueron sacrificados 21 días después de la infección y se realizó un análisis morfométrico de diferentes órganos. Los resultados mostraron un peso corporal y fecal significativamente mayor en el grupo tratado infectado. El peso del intestino delgado aumentó considerablemente en el grupo infectado y disminuyó en el grupo tratado. El volumen de páncreas, riñón derecho y corazón aumentó en el grupo infectado en comparación con el grupo control. A pesar del tratamiento, los volúmenes de estómago izquierdo, cerebro y riñón aumentaron en ambos grupos infectados en comparación con el grupo control, lo que indica la posibilidad de adaptaciones morfológicas irreversibles del huésped. La infección con S. venezuelensis puede aumentar tanto el volumen como el peso de los órganos -no necesariamente relacionados con el proceso de expulsión de Strongyloides-, incluso si la infección aguda estaba en remisión. Se discute brevemente una posible explicación de estas adaptaciones del huésped, incluida la aparición de plasticidad de los órganos. Los siguientes pasos incluyen un análisis histológico para comprobar la hipertrofia/hiperplasia y para ver si estos cambios morfológicos permanecen después de la infección.

Treatment of primate platynosomosis: A word of caution about the use of praziquantel in marmosets.

BACKGROUND: The successive reports of Platynosomum illiciens in Neotropical captive primates have increased interest in platynosomosis; however, its treatment is little known. METHODS: Callithrix penicillata (n = 10) naturally and chronically infected with P. illiciens were treated with praziquantel (25 mg/kg BW, three s.c. doses at 24 hours intervals), and coproparasitological tests performed over 67 days. The proportions of primates with a reduction in fecal egg counts (FEC) or negative results progressively increased after treatment, and at the last fecal tests, marmosets were negative. RESULTS AND CONCLUSIONS: Although all primates tolerated the initial days of study well, 40% (4/10) of them died between the 8th and 16th days after the onset of treatment. Clinical signs and necropsies indicated the occurrence of hepatic involvement, biliary obstruction, and cholangitis. Marmosets with a higher previous FEC were more likely to die after treatment. Use of praziquantel should be considered carefully on a case-by-case basis.

Evaluation of Kato-Katz and spontaneous sedimentation methods for the diagnosis of platynosomiasis in Neotropical primates.

Platynosomiasis is a parasitic infection reported in non-human primates, including marmosets, and is frequently difficult to diagnose. In this study, the Kato-Katz method and the spontaneous sedimentation method were evaluated for their usefulness in identifying Platynosomum eggs in fecal samples from Callithrix penicillata that naturally harbor Platynosomum illiciens. Spontaneous sedimentation allowed the diagnosis of 41.7% (5/12) and 66.7% (8/12) of infected marmosets from one and three slides, respectively, prepared from the same fecal sample. The examination of a single Kato-Katz thick smear detected 83.3% (10/12) of infection cases. The analysis of feces on three different days increased the rate of diagnosis, since 75% (9/12) and 100% (12/12) of the primates with platynosomiasis were identified using serial spontaneous sedimentation (3 slides/day) and the Kato-Katz method, respectively. The mean number of Platynosomum eggs per gram of feces determined via the Kato-Katz method was 71.7 (8-240). The spontaneous sedimentation method when performed in series is acceptable for the diagnosis of platynosomiasis. However, the Kato-Katz method, which was here used for the first time to detect this infection, has a higher diagnostic sensitivity and the advantage that a quantitative analysis of the eggs released in the host feces is possible.

Experimental centrocestiasis: Worm burden, morphology and fecundity of Centrocestus formosanus (Trematoda: Heterophyidae) in dexamethasone immunosuppressed mice.

Centrocestus formosanus is an intestinal foodborne trematode with medical and veterinary importance that remains with the pathological and immunological aspects of the infection in definitive host poorly studied. In the present study, we evaluated the effects of pharmacological immunosuppression by glucocorticoids in experimental centrocestiasis. Mice of the AKR/J strain were orally inoculated with 100 metacercariae of C. formosanus obtained in naturally infected fish (Australoheros facetus) collected in an urban reservoir from Brazil. Treatment with dexamethasone (25 mg/kg, via subcutaneous injection) was started 1h before infection of mice and then continued daily during 14 days post-infection. Untreated mice also infected with C. formosanus were used as control. At the end of the treatment course, all rodents were euthanized and adult parasites recovered from host intestines were subjected to morphological and morphometric analysis under optical microscopy. The worm burden in dexamethasone treated group [70±14 (41-85)] was significantly greater (p<0.0001) than that in the control group [15±4 (10-22)]. In addition, the parasites recovered from immunosuppressed mice were larger, with more developed reproductive structures and greater number of intrauterine eggs than in control mice. These parasite developmental changes induced by dexamethasone treatment are reported for the first time in experimental centrocestiasis. Moreover the higher parasite fecundity induced by glucocorticoid treatment had so far not been reported for any heterophyid species, which can have implications for the pathology and morbidity in infections caused by these parasites.

Evaluation of Kato-Katz and spontaneous sedimentation methods for the diagnosis of platynosomiasis in Neotropical primates / Avaliação dos métodos de sedimentação espontânea e Kato-Katz para o diagnóstico da platinossomose em primatas neotropicais

Platynosomiasis is a parasitic infection reported in non-human primates, including marmosets, and is frequently difficult to diagnose. In this study, the Kato-Katz method and the spontaneous sedimentation method were evaluated for their usefulness in identifying Platynosomum eggs in fecal samples from Callithrix penicillata that naturally harbor Platynosomum illiciens. Spontaneous sedimentation allowed the diagnosis of 41.7% (5/12) and 66.7% (8/12) of infected marmosets from one and three slides, respectively, prepared from the same fecal sample. The examination of a single Kato-Katz thick smear detected 83.3% (10/12) of infection cases. The analysis of feces on three different days increased the rate of diagnosis, since 75% (9/12) and 100% (12/12) of the primates with platynosomiasis were identified using serial spontaneous sedimentation (3 slides/day) and the Kato-Katz method, respectively. The mean number of Platynosomum eggs per gram of feces determined via the Kato-Katz method was 71.7 (8-240). The spontaneous sedimentation method when performed in series is acceptable for the diagnosis of platynosomiasis. However, the Kato-Katz method, which was here used for the first time to detect this infection, has a higher diagnostic sensitivity and the advantage that a quantitative analysis of the eggs released in the host feces is possible.

A platinossomose é uma infecção parasitária relatada em primatas não-humanos, inclusive saguis, cujo diagnóstico é frequentemente difícil. Neste estudo, os métodos de sedimentação espontânea e Kato-Katz foram avaliados quanto à sua utilidade na identificação de ovos de Platynosomum em amostras fecais de Callithrix penicillata naturalmente albergando Platynosomum illiciens. A sedimentação espontânea permitiu o diagnóstico de 41,7% (5/12) e 66,7% (8/12) dos saguis infectados a partir da análise de uma e três lâminas, respectivamente, preparadas de uma mesma amostra fecal. O exame de uma única lâmina de Kato-Katz detectou 83,3% (10/12) dos casos de infecção. A análise de fezes em três dias diferentes aumentou as taxas de diagnóstico, uma vez que 75% (9/12) e 100% (12/12) dos primatas que apresentaram a platinossomose foram identificados, usando-se a sedimentação espontânea (três lâminas/dia) e o Kato-Katz em série, respectivamente. O número médio de ovos de Platynosomum por g de fezes, determinado através do método de Kato-Katz, foi de 71,7 (8-240). O método de sedimentação espontânea, quando realizado em série, é aceitável para o diagnóstico da platinossomose. Entretanto, o método de Kato-Katz, o qual foi pela primeira vez usado para se detectar essa infecção, mostrou uma maior sensibilidade diagnóstica, com a vantagem de que é possível uma análise quantitativa dos ovos liberados nas fezes do hospedeiro.

Toxocara cati (Nematoda: Ascarididae) in Didelphis albiventris (Marsupialia: Didelphidae) from Brazil: a case of pseudoparasitism.

Eggs of Toxocara cati were found in the feces of Didelphis albiventris from a peridomestic urban environment in Brazil. Negative fecal tests following short-term captivity of the opossums, as well as the absence of ascaridids during necropsy, suggest the occurrence of pseudoparasitism. Implications of the findings for the epidemiology of toxocariasis are discussed.

Strongyloides stercoralis infection in marmosets: replication of complicated and uncomplicated human disease and parasite biology.

BACKGROUND: Strongyloides stercoralis can undergo an alternative autoinfective life cycle in the host, which, in some individuals can lead to a lethal infection. However, due to a number of factors, such as, the majority of those infected are from low-income backgrounds and the limitation in experimental models for studying human S. stercoralis, strongyloidiasis remains neglected. Improved knowledge of animal models that are susceptible to this parasite is needed in order to investigate the immunological mechanisms involved during infection and in particular to further understand the natural history of the autoinfective cycle. METHODS: Callithrix penicillata were inoculated subcutaneously with 100 (n = 2), 300 (n = 4) or 500 (n = 9) third-stage infective larvae (L3i) of S. stercoralis of human origin. Three marmosets received smaller inocula (i.e., one received 100 and two received 300 L3i) to ensure a greater capacity to withstand the infection after immunosuppression, which was triggered by administration of dexamethasone during early patency. Qualitative faecal analyses began at 7 days post-infection (DPI), and semi-quantitative tests were also performed for the dexamethasone-treated primates and the three matched controls. During the necropsies, specimens of S. stercoralis were recovered and tissue fragments were processed for histopathology. RESULTS: The mean prepatency and patency periods were 16.1 ± 3.0 and 161.1 ± 72.2 DPI, respectively. The marmosets typically tolerated the infection well, but immunosuppressed individuals exhibited higher numbers of larvae in the faeces and progressive clinical deterioration with late disseminated infection. In these cases, the number of females recovered was significantly higher than the number of inoculated L3i. Large quantities of larvae were observed migrating through the host tissues, and histopathology revealed pulmonary and intestinal injuries consistent with those observed in human strongyloidiasis. CONCLUSIONS: Both complicated and uncomplicated strongyloidiasis occur in C. penicillata that is described as a susceptible small non-human primate model for S. stercoralis. This host permits the maintenance of a human strain of the parasite in the laboratory and can be useful for experimental investigations of strongyloidiasis. In parallel, we discuss data related to the autoinfective cycle that provides new insights into the biology of S. stercoralis.

Toxocara cati (Nematoda: Ascarididae) in Didelphis albiventris (Marsupialia: Didelphidae) from Brazil: a case of pseudoparasitism / Toxocara cati (Nematoda: Ascarididae) em Didelphis albiventris (Marsupialia: Didelphidae) do Brasil: um caso de pseudoparasitismo

Eggs of Toxocara cati were found in the feces of Didelphis albiventris from a peridomestic urban environment in Brazil. Negative fecal tests following short-term captivity of the opossums, as well as the absence of ascaridids during necropsy, suggest the occurrence of pseudoparasitism. Implications of the findings for the epidemiology of toxocariasis are discussed.

Ovos de Toxocara cati foram encontrados nas fezes de Didelphis albiventris oriundos de um ambiente peridomiciliar urbano no Brasil. A negatividade dos exames de fezes após um curto período de cativeiro dos gambás e a ausência de nematódeos ascaridídeos durante a necropsia sugerem a ocorrência de pseudoparasitismo. As implicações dos achados para a epidemiologia da toxocarose são discutidas.

Strongyloides cebus (Nematoda: Strongyloididae) in Lagothrix cana (Primates: Atelidae) from the Brazilian Amazon: aspects of clinical presentation, anatomopathology, treatment, and parasitic biology.

Abstract : Seven cases of parasitism by Strongyloides cebus were identified in Lagothrix cana from Brazil. Aspects of the clinical presentation, treatment, pathology, and parasitic biology of these infections are described. Moderate to severe disease was observed, requiring hospitalization of 3 primates, and diarrhea was the most common clinical sign described. One L. cana individual died, for which ulcerative enteritis was the major finding upon histopathological analysis. The use of ivermectin in these atelids was safe and effective against the parasite. Parallel attempts to experimentally infect gerbils with the parasite failed. Lagothrix cana is presented as a new host for S. cebus. The evidence that Strongyloides infections are common in nonhuman primates under free-living conditions, and even more prevalent in captive animals, likely represents a neglected problem.

The Pampulha reservoir remains a potential urban focus of schistosomiasis mansoni in Brazil: changes in the occurrence patterns of Biomphalaria species and a new record of the parasite.

INTRODUCTION: The Pampulha reservoir has long been a focus of schistosomiasis transmission in Belo Horizonte, State of Minas Gerais, Brazil. The last malacological study conducted in this urban reservoir was more than two decades ago, and thus, an update on the distribution of the species of Biomphalaria as well as new data on the presence of Schistosoma mansoni in this water body are required. METHODS: The current distribution of Biomphalaria spp. in the Pampulha reservoir and their infection with S. mansoni was evaluated during 55 malacological surveys conducted between 2009 and 2012. RESULTS: Biomphalaria straminea displayed a high population density and distribution, and 13.7% (2,233/16,235) of the specimens collected were infected with larval trematodes other than Schistosoma mansoni. Biomphalaria tenagophila and Biomphalaria glabrata, species currently presenting a restricted distribution and small populations, displayed trematode infection rates of 15.2% (98/644) and 13% (83/640), respectively. Thirteen (2%) specimens of B. glabrata were found to be infected with S. mansoni. In addition, a historical review based on previous and new data on the occurrence patterns of Biomphalaria species in this reservoir is presented. CONCLUSIONS: The results indicate that the Pampulha reservoir remains a potential focus of urban schistosomiasis in Brazil, and significant changes in the occurrence patterns of Biomphalaria species were verified.

The Pampulha reservoir remains a potential urban focus of schistosomiasis mansoni in Brazil: changes in the occurrence patterns of Biomphalaria species and a new record of the parasite

Introduction The Pampulha reservoir has long been a focus of schistosomiasis transmission in Belo Horizonte, State of Minas Gerais, Brazil. The last malacological study conducted in this urban reservoir was more than two decades ago, and thus, an update on the distribution of the species of Biomphalaria as well as new data on the presence of Schistosoma mansoni in this water body are required. Methods The current distribution of Biomphalaria spp. in the Pampulha reservoir and their infection with S. mansoni was evaluated during 55 malacological surveys conducted between 2009 and 2012. Results Biomphalaria straminea displayed a high population density and distribution, and 13.7% (2,233/16,235) of the specimens collected were infected with larval trematodes other than Schistosoma mansoni. Biomphalaria tenagophila and Biomphalaria glabrata, species currently presenting a restricted distribution and small populations, displayed trematode infection rates of 15.2% (98/644) and 13% (83/640), respectively. Thirteen (2%) specimens of B. glabrata were found to be infected with S. mansoni. In addition, a historical review based on previous and new data on the occurrence patterns of Biomphalaria species in this reservoir is presented. Conclusions The results indicate that the Pampulha reservoir remains a potential focus of urban schistosomiasis in Brazil, and significant changes in the occurrence patterns of Biomphalaria species were verified. .

Trypanoxyuris (Paraoxyuronema) lagothricis (Nematoda: Oxyuridae) in Lagothrix cana (Primates: Atelidae) from Brazil.

During necropsy of a specimen of Lagothrix cana (É. Geoffroy, 1812) (Primates: Atelidae) from the Brazilian Amazon, pinworms were found in the large intestine. The intensity of infection was 64 parasites (17 males and 47 females) and there were no gross pathological changes related to parasitism. After morphological analysis the parasites were identified as Trypanoxyuris (Paraoxyuronema) lagothricis (Buckley, 1931) (Nematoda: Oxyuridae). This is the first record of this oxyurid species in primates in Brazil.

Trypanoxyuris (Paraoxyuronema) lagothricis (Nematoda: Oxyuridae) in Lagothrix cana (Primates: Atelidae) from Brazil / Trypanoxyuris (Paraoxyuronema) lagothricis (Nematoda: Oxyuridae) em Lagothrix cana (Primates: Atelidae) no Brasil

During necropsy of a specimen of Lagothrix cana (É. Geoffroy, 1812) (Primates: Atelidae) from the Brazilian Amazon, pinworms were found in the large intestine. The intensity of infection was 64 parasites (17 males and 47 females) and there were no gross pathological changes related to parasitism. After morphological analysis the parasites were identified as Trypanoxyuris (Paraoxyuronema) lagothricis (Buckley, 1931) (Nematoda: Oxyuridae). This is the first record of this oxyurid species in primates in Brazil.

Durante a necropsia de Lagothrix cana (É. Geoffroy, 1812) (Primates: Atelidae) oriundo da Amazônia brasileira, oxiurídeos foram encontrados no intestino grosso. A intensidade de infecção foi de 64 parasitos (17 machos e 47 fêmeas), não havendo alterações patológicas macroscópicas relacionadas ao parasitismo. Após análise morfológica os parasitos foram identificados como Trypanoxyuris (Paraoxyuronema) lagothricis (Buckley, 1931) (Nematoda: Oxyuridae). Este é o primeiro relato desta espécie de oxiurídeo em primatas no Brasil.

Parasitological and immunological aspects of early Ascaris spp. infection in mice.

Studies related to the immunobiological aspects of an Ascaris spp. infection are still scarce, especially those that aim to elucidate the early events of the immune response. In this study, we demonstrated a novel standardized method for early experimental Ascaris infection, providing additional information about the infectivity of eggs embryonated in vitro as well as the influence of host age on development of the infection. Finally, we characterised the immunopathology of early infection, focusing on the tissue and systemic cytokine profiles and the histopathology of infection in the lungs of BALB/c mice. Our results demonstrated that the highest egg infectivity occurred on the 100th and 200th days of in vitro embryonation and that 8 week-old BALB/c mice were more susceptible to infection than 16 week-old mice. Ascaris-infected mice showed an early, significant level of IL-5 production in the lungs 4 days p.i., followed by an increase in the level of neutrophils in the inflammatory infiltrate at 8 days p.i, which was correlated with the peak of larval migration in the tissue and a significant level of IL-6 production. The inflammatory infiltrate in the lungs was gradually replaced by mononuclear cells and eosinophils on the 10th and 12th days p.i., respectively, and an increase in TNF levels was observed. The downmodulation of systemic TCD4(+) cell numbers might suggest that T cell hyporesponsiveness was induced by the Ascaris spp. larvae, contributing to safeguarding parasite survival during larval migration. Taken together, the novel aspects of Ascaris infection presented here enabled a better understanding of the immunopathological events during larval migration, providing insight for further studies focused on immunisation and immunoprophylatic assays.

Experimental infection of Swiss and AKR/J mice with Centrocestus formosanus (Trematoda: Heterophyidae).

In order to better understand the biology of Centrocestus formosanus in a definitive host model, mice of Swiss and AKR/J strains were experimentally infected with 100 metacercariae of the parasite. Fourteen days post-infection, the rodents were killed and adult trematodes were recovered from the small intestine. The percentage of parasite recovery from AKR/J mice (11.4%) was significantly higher than that from Swiss mice (5.3%). Moreover, trematodes recovered from the AKR/J strain were more developed and had greater fecundity. Peculiarities concerning the mice's immune system could explain the difference in susceptibility and in worm development seen in the present study. The data obtained confirm that mice are susceptible to infection with C. formosanus and indicate that the AKR/J strain provides a more favorable environment for parasite development.

Callithrix penicillata as a nonhuman primate model for strongyloidiasis.

In order to better understand experimental strongyloidiasis in small New World primates, and to evaluate aspects of reinfection and immunosuppression induced by glucocorticoids, nine specimens of Callithrix penicillata (Primates: Cebidae) were administered (by subcutaneous injection, sc) 3000 infective larvae of a strain of Strongyloides venezuelensis (Rhabditida: Strongyloididae) that had been maintained in successive passages through AKR/J mice since 1987. The mean prepatent period was 5.6 ± 0.7 days post-infection (DPI). The mean patent period of infection among the untreated animals (marmosets 1-7) was 123.4 ± 61.4 DPI. Two animals (marmosets 8 and 9) received dexamethasone (2.5 mg/kg, sc) for five consecutive days starting on the 20th day after infection, but this treatment did not alter the course of the infection, and the patent period for these animals was 100.5 ± 58.7 DPI (59 and 142, respectively). Stool examination showed that the highest quantities of parasite eggs were expelled between the 8th and 19th days after inoculation of the larvae. Thereafter, there was a gradual reduction in the number of parasite eggs in feces of all marmosets. During the chronic phase of the infection, before completely negative parasitological findings were obtained, the parasitological examinations were intermittently positive. Reinfection of three of these animals did not result in new positive examinations. However, given the receptiveness of these animals to initial infection with S. venezuelensis and their similarities to human beings, it is proposed that C. penicillata could be used as a nonhuman primate model for experimental strongyloidiasis.

Dermatite cercariana por esquistossomatídeos de aves: é possível a ocorrência de casos no Brasil? / Swimmers’ itch by avian schistosomes: is it possible in Brazil?

A dermatite cercariana causada por larvas de esquistossomatídeos de aves tem sido considerada uma enfermidade emergente. Embora ainda não haja relato de casos no Brasil, algumas espécies destes trematódeos já foram encontradas em aves e os potenciais hospedeiros intermediários (moluscos) estão amplamente distribuídos pelo país. Em razão da dificuldade de diagnósticoclínico diferencial da dermatite causada por larvas de Schistosoma mansoni, é possível que outras dermatites cercarianas sejam negligenciadas em nosso meio. Neste trabalho são discutidos aspectos relacionados à identificação de áreas de risco, à pesquisa de formas larvares em moluscos aquáticos, às alterações clínicas verificadas em humanos, ao tratamento e à profilaxia desta enfermidade. Concluiu-se que são necessários esforços para o diagnóstico da dermatite cercariana por outrosesquistossomatídeos e também que sejam desenvolvidos estudos visando ampliar o conhecimento sobre a ocorrência destes parasitos no Brasil.

Levantamento de parasitos intestinais nas áreas urbana e rural de Itambé do Mato Dentro, Minas Gerais, Brasil / Survey of intestinal parasites in urban and rural areas of Itambé do Mato Dentro, Minas Gerais, Brazil

Com o objetivo de verificar a distribuição de parasitos intestinais em Itambé do Mato Dentro (região central de Minas Gerais) e comparar os dados referentes à área urbana com os dos distritos rurais do município, realizou-se uma análise dos resultados de rotina de exames parasitológicos de fezes (sedimentação espontânea) de 817 pacientes obtidos entre julho de 2005 e fevereiro de 2007. Verificou-se que 33,2por cento dos exames foram positivos, sendo observada mais de uma espécie de parasito em 8,1por cento dos casos. A ocorrência de parasitos intestinais na zona rural (39,5por cento) foi significativamente maior (p menor que 0,05) que na área urbana (24,3por cento).

In order to evaluate the distribution of intestinal parasites in Itambé do Mato Dentro (central region of Minas Gerais) and to compare data of the urban area to those of rural districts of the municipality, an analysis of stool parasitological tests was carried out. Between July 2005 and February 2007, results of 817 patients tested using the sedimentation method were obtained. It was verified that 33.2% of testswere positive and more than one species of parasites were observed in 8.1% of cases. The occurrence of intestinal parasites in rural areas (39.5%) was significantly higher (p <0.05) than in urban areas (24.3%).