Detection of Sarcocystis spp. and Toxoplasma gondii in swine and detection of DNA of these protozoa in tissues and sausages / Soroprevalência de Sarcocystis spp. e Toxoplasma gondii em suínos e detecção do DNA desses protozoários em tecidos e embutidos

Abstract The seroprevalence of Sarcocystis spp. and Toxoplasma gondii was researched in swine raised in Santa Maria, RS, Brazil. Serum samples from 84 pigs from 31 farms were tested using indirect immunofluorescence assay (IFA) for both agents. Additionally, 53 samples of pork sausages and tissues destined for human consumption, including: salami, sausage, black pudding, heart, tongue, brain, and rib muscle, were submitted to PCR to detect DNA for each agent. The frequency of anti-Sarcocystis spp. antibodies was 36.9% (31/84), with titers ranging from 32 to 1024, and 25% (21/84) for anti-T. gondii antibodies, with titers ranging from 64 to 2048. Sarcocystis spp. and T. gondii DNA were detected in 67.9% (36/53) and 13.2% (7/53) of samples, respectively. The presence of antibodies and the detection of DNA from Sarcocystis spp., and T. gondii suggests that the pigs were infected and may serve as an important reservoir for both parasites. The infection by these protozoa in the swine population is relevant to public health due to their zoonotic potential.

Resumo A soroprevalência de Sarcocystis spp. e Toxoplasma gondii foi pesquisada em suínos criados em Santa Maria, RS, Brasil. Amostras de soro de 84 suínos de 31 fazendas foram testadas pela reação deimunofluorescência indireta (IFA) para ambos os agentes. Adicionalmente, 53 amostras de embutidos suínos e tecidos cárneos destinados ao consumo humano, incluindo: salame, linguiça, morcela, coração, língua, cérebro e músculo da costela foram submetidas à PCR para detecção de DNA para cada agente. A frequência de anticorpos anti-Sarcocystis spp. foi de 36,9% (31/84), com títulos variando de 32 a 1.024; e 25% (21/84) para anticorpos anti-T. gondii, com títulos variando de 64 a 2048. A presença de DNA de Sarcocystis spp. e T. gondii foi detectada em 67,9% (36/53) e 13,2% (7/53) das amostras avaliadas, respectivamente. A detecção de anticorpos e DNA de Sarcocystis spp. e T. gondii sugere que os suínos foram infectados e podem servir como um importante reservatório de ambos os parasitas. A circulação desses agentes na população suína é relevante para a saúde pública devido ao seu potencial zoonótico.

Sarcocystis neurona, seroprevalence of antibodies in equines and research of oocystis in opossum in Ilhéus - Itabuna microregion, Bahia, Brazil / Sarcocystis neurona, seroprevalência de anticorpos em equinos e pesquisa de oocistos em gambás na microrregião de Ilhéus - Itabuna, Bahia, Brasil

Abstract The aims of this study were to determine the seroprevalence of Sarcocystis neurona antibodies in equines in the Ilhéus-Itabuna microregion (BA), and identify possible factors associated with infection. The presence of sporocysts/oocysts of Sarcocystis spp. was also verified in Didelphis spp. A total of 669 serum samples were collected from equines in 56 properties located in 12 municipalities in the region. Indirect fluorescent antibody test was performed with slides containing merozoites of the S. neurona, using a cut-off titer of 1:80. Occurrence of 7.92% of anti-S. neurona antibodies was observed in the sampled equines. The purposes trade and work were significantly associated with the presence of antibodies (p<0.05), and being used for the purpose of work (21.6%) was considered a risk factor, while being used for the purpose of trade (3.6%) was a protective factor. A total of 25 Didelphis spp. was captured for research on sporocysts/oocysts in stool samples and intestinal scrapings, being all negative. Didelphis spp. were all negative for the presence of Sarcocystis spp. and this circumstance does not change the fact that seroprevalence of S. neurona has been observed in horses raised in the southern Bahia.

Resumo O presente estudo foi realizado na microrregião de Ilhéus-Itabuna, Bahia. Os objetivos deste estudo foram determinar a soroprevalência de anticorpos contra Sarcocystis neurona em equinos da microrregião Ilhéus-Itabuna (BA) e identificar possíveis fatores associados à infecção. A presença de esporocistos/oocistos de Sarcocystis spp. também foi pesquisada em Didelphis spp. Foram coletadas 669 amostras de soro de equinos em 56 propriedades localizadas em 12 municípios da região. Foi utilizada a reação de imunofluorescência indireta (RIFI), utilizando-se lâminas confeccionadas com merozoítos de Sarcocystis neurona (cepa SN138) e ponto de corte na diluição de 1:80. A ocorrência de anticorpos anti- S. neurona, nos equinos amostrados, foi de 7,92%. As finalidades dos animais - comércio e trabalho - apresentaram-se significativas (p<0.05), sendo que a finalidade trabalho (21,6%) foi considerada fator de risco, enquanto a finalidade comércio (3,6%) foi considerada fator de proteção. Foram capturados 25 Didelphis spp., para pesquisa de esporocistos/oocistos em amostras de fezes e raspado de mucosa intestinal. Todos os Didelphis spp. foram negativos para a presença de Sarcocystis spp., mesmo assim essa circunstância não alterou o fato da ocorrência de S. neurona ter sido observada em cavalos criados na mesorregião do sul da Bahia.

Sarcocystis neurona and related Sarcocystis spp. shed by opossums (Didelphis spp.) in South America / Sarcocystis neurona e Sarcocystis spp. relacionados, excretados por gambás (Didelphis spp.) na América do Sul

Abstract Protozoan parasites of the genus Sarcocystis are obligatory heteroxenous cyst-forming coccidia that infect a wide variety of animals and encompass approximately 200 described species. At least four Sarcocystis spp. (S. falcatula, S. neurona, S. lindsayi and S. speeri) use opossums (Didelphis spp.) as definitive hosts, and two of them, S. neurona and S. falcatula, are known to cause disease in horses and birds, respectively. Opossums are restricted to the Americas, but their distribution in the Americas is heterogeneous. Five Didelphis spp. are distributed in South America (D. aurita, D. albiventris, D. marsupialis, D. imperfecta and D. pernigra) whereas just one opossum species (D. virginiana) is found in North America. Studies conducted in the last decades show that Sarcocystis spp., derived from South American Didelphis spp., have biological and genetic differences in relation to Sarcocystis spp. shed by the North American opossum D. virginiana. The aim of this review was to address the peculiar scenario of Sarcocystis species shed by South American opossums, with a special focus on diagnosis, epidemiology, and animal infections, as well as the genetic characteristics of these parasites.

Resumo Parasitos protozoários do gênero Sarcocystis são coccídios heteroxenos formadores de cistos, que infectam variadas espécies animais e compreendem cerca de 200 espécies descritas. Pelo menos quatro Sarcocystis spp. (S. falcatula, S. neurona, S. lindsayi e S. speeri) utilizam gambás (Didelphis spp.) como hospedeiros definitivos; e duas delas, S. neurona and S. falcatula são conhecidas por causarem doença em equinos e aves, respectivamente. Gambás didelfídeos são restritos ao continente americano, contudo são distribuídos de forma heterogênea nas Américas. Cinco Didelphis spp. são distribuídos na América do Sul (D. aurita, D. albiventris, D. marsupialis, D. imperfecta e D. pernigra), enquanto somente uma espécie (D. virginiana) é encontrada na América do Norte. Trabalhos conduzidos, nas últimas décadas, mostram que Sarcocystis spp. derivados de Didelphis spp. sul-americanos possuem diferenças biológicas e genéticas, quando comparados a Sarcocystis spp. excretados pelo gambá norte-americano D. virginiana. O objetivo desta revisão é discutir a situação peculiar das espécies de Sarcocystis na América do Sul com um foco especial em diagnóstico, epidemiologia e infecções animais, assim como nas características genéticas desses parasitos.

Low prevalence of infection by Sarcocystis neurona in horses from the State of Alagoas, Brazil / Baixa prevalência da infecção por Sarcocystis neurona em cavalos do estado de Alagoas, Brasil

Abstract The aim of this study was to determine the prevalence of infection by Sarcocystis neurona in horses and identify potential risk factors. Were analyzed 427 samples from 36 farms in 21 municipalities in the Alagoas State, Brazil. Presence of anti-S. neurona antibodies was diagnosed by indirect immunofluorescence antibody test (IFAT) and was confirmed using the immunoblot test. Risk factors were assessed through investigative questionnaires on animal management on the farms. The prevalence of anti-S.neurona antibodies was 2.8% (confidence interval, CI: 1.5-4.9%) from IFAT and 1.6% (CI:0.8-3.34%) from immunoblot, and there were positive horses on 16.6% of the studied farms. None of the variables studied presented associations with serological status for S. neurona. This is the first report on infection by S. neurona in horses reared in Alagoas, Brazil showing a low exposure to S. neurona in this region, but with significant numbers of foci.

Resumo Objetivou-se neste estudo determinar a prevalência e os fatores de risco associados à infecção por Sarcocystis neurona em equinos. Foram analisadas 427 amostras de 36 propriedades localizadas em 21 municípios do estado de Alagoas. O diagnóstico de anticorpos anti-S. neurona foi realizado pela técnica de Imunofluorescência Indireta (IFI) e confirmada por immunoblot. O estudo dos fatores de risco foi realizado a partir de questionários investigativos sobre o manejo dos animais nas propriedades. A prevalência de anticorpos anti-S. neurona foi de 2,8% (I.C. 1,5-4,9%) na IFI e de 1,6% (I.C. 0,8-3,34%) no immunoblot com equinos positivos em 16,6% das propriedades estudadas. Nenhuma variável estudada apresentou associação com o status sorológico para S. neurona. Este é o primeiro relato da infecção por S. neurona em equinos criados no Estado de Alagoas, Brasil, confirmando que os animais desta região têm baixa exposição a S. neurona, mas com significativo número de focos.

Sarcocystis spp. in red deer (Cervus elaphus), fallow deer (Dama dama), and pudu (Pudu pudu) in southern Chile / Sarcocystis spp. em veado (Cervus elaphus), Gamo (Dama dama) e Pudu (Pudu pudu) no sul do Chile

Worldwinde, cervids are considered an important source of infection and dissemination of a wide variety of pathogens, both for farm animals and humans. Among this diseases is sarcosporidiosis, which is a parasitic disease caused by Sarcocystis spp. (Protozoa: Apicomplexa). Most frequent clinical signs are hemolytic anemia, weakness, weight loss and decrease of growth and some species of Sarcocystis might cause abortions. The clinical disease in ruminants is fairly rare but the infection is very frequent. Infections are accumulative and the parasite does not generate immunity in any of the hosts. Ovine sarcosporidiosis is a serious issue in the some regions of Chile due to the macrocysts located in the muscle which means condemnation of the whole carcass. Sarcocystis spp. has been widely reported in red deer and other cervid species but in Chile the situation remains unknown. Nowadays there is little to no evidence of Sarcocystis in foreign deer in Chile and there is only one report of the parasite on pudu. The main goal of this study is to demonstrate the presence of Sarcocystis spp. in myocardium of red deer and fallow deer in Chile, and confirm the presence of Sarcocystis spp. in pudu. All cervid cases from 1994 to 2013 of the Institute of Animal Pathology of the Universidad Austral de Chile were reviewed. The animals selected were those in which a myocardium sample was taken. From the histopathological samples observed, it was found that 5 of the 9 red deer, 1 of the 4 fallow deer and in 11 of the 23 pudu there were Sarcocystis cysts in the myocardium. This study represents the first record for Chile of Sarcocystis spp. in myocardium of red deer and fallow deer. Stablishing the red deer, fallow deer and pudu as hosts of Sarcocystis aids to have a better understanding of the parasite epidemiology in Chile and the role of wild and captive cervids in the maintenance and spread of these parasites.(AU)

No mundo, os cervos são considerados uma fonte de infecção e propagação de uma grande variedade de patógenos para animais de criação e para os seres humanos. Entre estas doenças está a sarcosporidiosis, que é uma doença parasitária causada por Sarcocystis spp. (Protozoa: Apicomplexa). Os sinais clínicos mais comuns são anemia hemolítica, fraqueza, perda de peso e diminuição do crescimento e em algumas espécies de Sarcocystis podem causar abortos. A doença clínica em ruminantes é bastante rara, mas a infecção é muito comum. As infecções são cumulativos e o parasita não gera imunidade em nenhum dos seus hospedeiros. A Sarcosporidiosis ovina é um problema grave em algumas regiões do Chile devido a microcistos localizados no músculo provocando a reprovação total da carcaça. Sarcocystis spp. tem sido amplamente relatado em cervos vermelhos e outras espécies de cervídeos, mas no Chile a sua situação permanece desconhecida. Atualmente há pouca ou nenhuma evidência de Sarcocystis em cervos introduzidos no Chile e há apenas um relatório do parasita em pudú. O principal objetivo deste estudo é demonstrar a presença de Sarcocystis spp. no miocárdio no veado vermelho e cervo gamo no Chile e confirmar a presença de Sarcocystis spp. em pudus. Revisaram-se todos os casos de cervos desde 1994-2013 do Instituto de Patologia Animal da Universidad Austral de Chile. Os animais selecionados para o estudo foram aqueles em que se tomou amostra de miocárdio. Das amostras histopatológicas observadas, verificou-se que em cinco dos nove cervos vermelhos, em um dos quatro veados gamo e 11 dos 23 pudus tinham cistos de Sarcocystis no miocárdio. Este estudo representa o primeiro relatório para o Chile de Sarcocystis spp. no miocárdio de veados vermelhos e cervo gamo. Definir o veado vermelho, o cervo gamo e os pudú como anfitriões de Sarcocystis ajuda a uma melhor compreensão da epidemiologia deste parasita no Chile e o papel de cervos selvagens e em cativeiro para a manutenção e divulgação deste parasita.(AU)

Seroepidemiology of Sarcocystis neurona, Toxoplasma gondii and Neospora spp. among horses in the south of the state of Minas Gerais, Brazil / Soroepidemiologia de Sarcocystis neurona, Toxoplasma gondii e Neospora spp. em Equinos no Sul do Estado de Minas Gerais, Brasil

Abstract The present study used the indirect fluorescent antibody test (IFAT) to determine the seroprevalence of Sarcocystis neurona, Toxoplasma gondii and Neospora spp., and evaluated the variables associated with these infections among 506 apparently healthy horses, reared in the south of the state of Minas Gerais, Brazil. This study was conducted between April 2012 and October 2013. Among the horses, the true prevalence of S. neurona was 26% (95% CI: 22.0-30.4%), T. gondii 19.9% (95% CI: 15.5-24.8%) and Neospora spp. 23.9% (95% CI: 19.9-28.1%); and among the farms, 88.3% (95% CI: 74.4-91.6%), 71.6% (95% CI: 41-92.8%) and 85% (95% CI: 70.7-96.1%), respectively. Regarding mixed infection, 17 horses (3.4%) were seropositive for both S. neurona and T. gondii, 16 (3.2%) for T. gondii and Neospora spp. and 14 (2.8%) for S. neurona and Neospora spp. The associations between seropositivity and variables relating to the structure of the farm, management and health were analyzed using the logistic regression analysis, through the generalized estimating equations (GEE). The results suggest that the south of Minas Gerais is an enzootic area for S. neurona, T. gondii and Neospora spp. among horses, with prevalence of asymptomatic subclinical or chronic infections.

Resumo Este estudo determinou, pela reação de imunofluorescência indireta (RIFI), a soroprevalência de Sarcocystis neurona, Toxoplasma gondii e Neospora spp., e avaliou as variáveis associadas com a infecção, em 506 equinos, aparentemente sadios, criados no Sul de Minas, Brasil. O estudo foi realizado no período de abril de 2012 a outubro de 2013. Entre equinos, a prevalência verdadeira para S. neurona foi de 26% (IC 95%= 22,0-30,4%); para T. gondii de 19,9% (IC 95%= 15,5-24,8%); e para Neospora spp. de 23,9% (IC 95%= 19,9-28,1%); e entre propriedades, 88,3% (IC 95%= 74,4-91,6%), 71,6% (IC 95% = 41-92,8%), e 85% (IC 95%= 70,7-96,1%), respectivamente. Em relação à infecção mista, 17 (3,4%) equinos foram soropositivos para S. neurona e T. gondii, 16 (3,2%) para T. gondii e Neospora spp., e 14 (2,8%) para S. neurona e Neospora spp. A associação entre soropositividade e variáveis relacionadas à estrutura da propriedade, manejo e sanidade, foi analisada, utilizando-se a análise de regressão logística estimada por Generalized Estimating Equations (GEE). Os resultados sugerem que o Sul de Minas é área enzoótica para S. neurona, T. gondii e Neospora spp. em equinos, com predomínio de infecções subclínicas ou crônicas, assintomáticas.

Prevalence of antibodies against Neospora spp. and Sarcocystis neurona in donkeys from northeastern Brazil / Prevalência de anticorpos contra Neospora spp e Sarcocystis neurona em jumentos do nordeste do Brazil

Abstract Sarcocystis neurona and Neospora hughesi are coccidian protozoa that can cause neurological illness in horses in America. In this study we report seroprevalence of Neospora spp. andS. neurona in sera of 333 donkeys from the northeastern region of Brazil. Antibodies to Neospora spp. were detected in 2% (7 donkeys) of 333 sera tested by the indirect fluorescent antibody test (IFAT) with a cut-off dilution of 1:40. Antibodies to S. neurona were found in 3% (10 donkeys) of the samples tested by IFAT (cut-off ≥50) and 21% (69 donkeys) by the direct agglutination test (SAT ≥50). The SAT and IFAT results for S. neurona showed a poor concordance (value of Kappa=0.051). This is the first report ofNeospora spp. antibodies in Brazilian donkeys and the first detection of antibodies against S. neurona in this animal species.

Resumo Sarcocystis neurona e Neospora hughesi são protozoários coccídios que infectam equídeos e são responsáveis por doenças neurológicas nessas espécies. Neste estudo, a soroprevalência de infecção porS. neurona e Neospora spp. foi determinada em amostras de 333 soros de jumentos da Região Nordeste do Brasil. Anticorpos contra Neospora spp. foram detectados em 2% (7 jumentos) dos 333 animais examinados pela reação de imunofluorescência indireta (RIFI), com ponto de corte de 40. Anticorpos contra S. neurona foram detectados em 3% (10 jumentos) das amostras pela RIFI (ponto de corte de 50) e em 21% (69 jumentos) pela técnica de aglutinação direta (SAT - ponto de corte de 50). SAT e RIFI, para diagnóstico de S. neurona, apresentaram uma baixa concordância (Kappa = 0,051). Essa é a primeira observação de anticorpos anti-N. caninum em jumentos brasileiros e a primeira detecção de anticorpos contra S. neurona nessa espécie.

Investigação de anticorpos contra Sarcocystis neurona e Sarcocystis cruzi em equinos / Investigation of antibodies against Sarcocystis neurona and Sarcocystis cruzi in equines

Sarcocystis neurona is the primary agent for Equine Protozoal Myeloencephalitis (EPM), important neurological disease characterized by behavior or muscular changes, that impairs animal performance and husbandry. Sarcocystis cruzi is a pathogen related to myositis in cattle. Although related the life cycles of the parasites are distinct. S. neurona has opossums (Didelphis spp.) and S. cruzi, dogs as definitive hosts. However, S. neurona and S. cruzi may undergo cross-reactivity in serological tests, interfering on results of EPM ante-mortem diagnostic tests. In the present study, serology of 189 mares was performed by indirect immunofluorescence antibody test, using antigens of S. neurona and S. cruzi in order to assess the exposure degree of animals to antigens. Analyzing the results, it was observed that most of the animals (84.13%) reacted with at least one protozoal species and the number of animals which showed antibodies against S. cruzi was greater than S. neurona (80.42% and 33.86%, respectively) and a third of seropositive animals reacted to antigens of both species.(AU)

Sarcocystosis among Wild Captive and Zoo Animals in Malaysia

Sarcocystis sp. infection was investigated in 20 necropsied captive wild mammals and 20 birds in 2 petting zoos in Malaysia. The gross post-mortem lesions in mammals showed marbling of the liver with uniform congestion of the intestine, and for birds, there was atrophy of the sternal muscles with hemorrhage and edema of the lungs in 2 birds. Naked eye examination was used for detection of macroscopic sarcocysts, and muscle squash for microscopic type. Only microscopically visible cysts were detected in 8 animals and species identification was not possible. Histological examination of the sections of infected skeletal muscles showed more than 5 sarcocysts in each specimen. No leukocytic infiltration was seen in affected organs. The shape of the cysts was elongated or circular, and the mean size reached 254 x 24.5 micrometer and the thickness of the wall up to 2.5 micrometer. Two stages were recognized in the cysts, the peripheral metrocytes and large numbers of crescent shaped merozoites. Out of 40 animals examined, 3 mammals and 5 birds were positive (20%). The infection rate was 15% and 25% in mammals and birds, respectively. Regarding the organs, the infection rate was 50% in the skeletal muscles followed by tongue and heart (37.5%), diaphragm (25%), and esophagus (12.5%). Further ultrastructural studies are required to identify the species of Sarcocystis that infect captive wild animals and their possible role in zoonosis.

Lambs Infected with UV-Attenuated Sporocysts of Sarcocystis ovicanis Produced Abnormal Sarcocysts and Induced Protective Immunity against a Challenge Infection

The present study surveyed the prevalence of natural infection of the sheep esphagus muscle with sarcocysts of Sarcocystis ovicanis and examined induction of protective immunity using UV-attenuated sporocysts. The overall prevalence of natural infection of the sheep was 95%. Infectivity of the collected sarcocysts was confirmed by shedding of sporulated oocysts after feeding infected esophageal tissues to dogs. To induce protective immunity, lambs were immunized 3 times (once a week) with 1.5 x 10(4) sporocysts exposed to UV-light for 30 min (UV-30 group) or 60 (UV-60 group) min and then challenged with 1.5 x 10(4) normal sporocysts at the 3rd week post the 1st vaccination. These lambs showed high survival and less clinical signs of sarcocystosis than normal infected lambs. The attenuated sporocysts produced abnormal cysts; small in size and detached from the muscle fiber. These abnormalities were more obvious in UV-60 group than UV-30 group. Also, the IFN-gamma level and lymphocyte percentage were increased while the total leukocyte count was decreased in the UV-60 group compared with other groups. The high level of IFN-gamma may be an evidence for the induction of Th1 responses which may have protective effect against a challenge infection.

The Sarcocystis-cyst containing beef and pork as the sources of natural intestinal sarcocystosis in Thai people.

BACKGROUND: Human intestinal sarcocystosis is a zoonotic disease caused by two coccidians, i.e. Sarcocystis fusiformis (syn. S. bovihominis, S. hominis) due to consumption of raw infected beef and Sarcocystis meischeriana (syn. S. suihominis) due to consumption of infected raw pork. In 1987, survey of the macroscopic S. fusiformis cysts in market beef mainly from old water buffalos aged more than 15 years were commonly observed in Bangkok. In 2005, the macroscopic cyst was no longer seen in beef of cattle and water buffalo aged less than three years. OBJECTIVE: The epidemiological investigation of Sarcocystis spp. infected meat in Bangkok and Lampang. MATERIAL AND METHOD: Samples for each of the tongue and beef of cattle and water buffalo, pork from Bangkok markets and pork of domestic swine from some remote villages in various subprovinces (Ampurs) in Lampang were obtained for microscopic examination by H and E and selectively by PAS staining. RESULTS: The microscopic S. fusiformis cysts were seen in all five specimens of tongues and ten specimens of muscles of cattle and water buffalo obtained from fresh-food markets in Bangkok. Ten samples of pork from Bangkok markets revealed no coccidian infection. The microscopic S. meischeriana cysts were seen in three specimens of swine muscles collected from two subprovinces in Lampang. CONCLUSION: The present merozoites in coccidian cysts retrieved from beef and pork are similar to those previously observed in human intestine. This may histologically indicate an invasive sarcocystosis by both species leading to a condition presently known as chronic inflammation of undetermined etiology in man.

The potential usefulness of the modified Kato thick smear technique in the detection of intestinal sarcocystosis during field surveys.

A total of 479 stool specimens were collected from rural communities of Ubon Ratchathani Province, Thailand and examined by two techniques: the modified Kato thick smear and the direct smear. The prevalence of Opisthorchis viverrini (14.8%), hookworm (10.2%), Sarcocystis spp (4.6%), Taenia spp (2.9%), Strongyloides stercoralis (2.1%), Giardia lamblia (1.2%), Echinostoma spp (0.6%), Ascaris lumbricoides (0.4%), Entamoeba histolytica (0.2%), Chilomastix mesnili (0.2%) and Endolimax nana (0.2%) were determined. The morphology of the Sarcocystis spp sporocysts examined by both procedures looked similar and was found to be easily recognizable. Among these specimens, 22 cases (4.6%) were positive for Sarcocystis infection detected by the modified Kato technique, whereas only one case (0.2%) was detected by both techniques. These differences were found to be statistically significant (p < 0.05), indicating that the modified Kato technique was decidedly more sensitive than the direct smear procedure in identifying Sarcocystis infection. An epidemiological survey was conducted in Khon Kaen Province involving 1124 stool samples using the modified Kato technique. The greatest frequency was Opisthorchis viverrini at 32.0% while the second highest was Sarcocystis spp at 8.0%. The prevalences of hookworm, Echinostoma spp, Taenia spp, Trichuris trichiura and Enterobius vermicularis were 2.7, 2.1, 1.0, 0.2 and 0.2%, respectively. Other than opisthorchiasis, northeastern Thailand may be an endemic area for sarcocystosis. This is the first report of the applicability and potential usefulness of the Kato thick smear technique for the diagnosis of Sarcocystis infection in a field survey.

Prevalence of Sarcocystis infection in meat-producing animals in Mongolia.

A survey of Sarcocystis infection was conducted in Mongolia between June 1998 and July 1999. Samples of muscle were taken from the diaphragm, heart, tongue, esophagus,and intercostal region of cattle, yak, hainag, sheep, horses, and camels. A muscle compress method was used to determine the prevalence of infection: cattle 90.0% (27/30), yak 93.3% (28/30), hainag 100% (30/30), sheep 96.9% (753/777), horses 75% (3/4) and camels 100% (5/5). Of the various muscles, heart was the most commonly infected in cattle (100%), yak (86.7%), and hainag (100%); tongue was most likly to be infected in sheep (100%) and horses (100%).

A survey of bovine, bubaline and swine sarcocystosis in the Philippines.

In a survey conducted from January to December, 1994, muscle tissues in 12 out of 22 slaughtered carabaos ages 8-17 years old and obtained from the Food Terminal Inc, Abbatoir in Laguna showed numerous white and creamy elliptic-shaped soft bodied macrocysts in the throat muscles. Microscopic examination of the throat and cardiac muscle tissues revealed the presence of fusiform-shaped microcysts. Our observations are consistent with previous reports incriminating Sarcocystis fusiformis as the most important etiologic agent of bubaline sarcocystosis in the country. In a survey of bovine sarcocystosis in muscle tissues of imported Australian cattle (Brahman Breed) and native cattle obtained from various slaughter houses in Manila and suburbs, prevalence rates of 17% (98/577) and 3% (1/31) were noted, respectively. Sarcocysts were predominant in skeletal muscles and to a lesser extent in cardiac, esophageal and diaphragm muscle tissues. Light microscopic examination of sarcocysts morphology suggests Sarcocystis cruzi (= Sarcocystis bovis), and Sarcocystis hominis (= Sarcocystis bovihominis) or Sarcocystis hirsuta (= Sarcocystis bovifelis) as the likely etiologic agents of bovine sarcocystosis in the country. Of the 225 swines examined, only muscle tissues from a 6-month old swine revealed very young sarcocysts (= metrocytes). A review of available documented studies on sarcocystosis suggests that to date, our findings may represent the first data on the prevalence of bovine and swine sarcocystosis in the Philippines.

Intestinal sarcocystosis in Thai laborers.

To determine the prevalence of Sarcocystis and other intestinal parasites in Thai laborers who were going abroad for work, stool examinations of 362 asymptomatic laborers were studied. The four most frequently parasites found in stool were Sarcocystis sp (23.2%), Opisthorchis viverini (40.3%), hookworm (21.5%), and Strongyloides stercoralis (14.1%). Giardia intestinalis (5.2%), Entamoeba coli (1.7%), Endolimax nana (2.5%), Blastocystis hominis (4.1%), Echinostoma sp (3.6%), Trichuris trichiura (0.3%), Taenia sp (1.7%), Hymenolepis nana (0.6%), and Enterobius vermicularis (0.3%) were present at low rates. Sarcocystis were frequently found in male laborers (83.3%) (p < .01). The laborers from northeastern Thailand (n = 278) had a higher prevalence (26.6%) of Sarcocystis infection (p < .01). This study shows that Thai laborers, particularly from northeastern Thailand, are commonly infected with intestinal parasites. The high prevalence rates of Sarcocystis and other intestinal parasites in this study were indicative of the local habit of eating raw beef and pork, poor living conditions, and low levels of hygiene in Thai laborers. Sarcocystosis could be a significant food-borne zoonotic infection in Thailand.

Review of sarcocystosis in Malaysia.

Sarcocystis is a tissue coccidian with an obligatory two-host life cycle. The sexual generations of gametogony and sporogony occur in the lamina propria of the small intestine of definitive hosts which shed infective sporocysts in their stools and present with intestinal sarcocystosis. Asexual multiplication occurs in the skeletal and cardiac muscles of intermediate hosts which harbor Sarcocystis cysts in their muscles and present with muscular sarcocystosis. In Malaysia, Sarcocystis cysts have been reported from many domestic and wild animals, including domestic and field rats, moonrats, bandicoots, slow loris, buffalo, and monkey, and man. The known definitive hosts for some species of Sarcocystis are the domestic cat, dog and the reticulated python. Human muscular sarcocystosis in Malaysia is a zoonotic infection acquired by contamination of food or drink with sporocysts shed by definitive hosts. The cysts reported in human muscle resembled those seen in the moonrat, Echinosorex gymnurus, and the long-tailed monkey, Macaca fascicularis. While human intestinal sarcocystosis has not been reported in Malaysia so far, it can be assumed that such cases may not be infrequent in view of the occurrence of Sarcocystis cysts in meat animals, such as buffalo. The overall seroprevalence of 19.8% reported among the main racial groups in Malaysia indicates that sarcocystosis (both the intestinal and muscular forms) may be emerging as a significant food-borne zoonotic infection in the country.

Sarcocystis in caribou (Rangifer tarandus terraenorae) in Newfoundland.

Prevalence of species of Sarcocystis in muscle of 36 caribou, Rangifer tarandus terraenorae, shot in Newfoundland, Canada, was 53%. A greater percentage of infected animals were obtained from the central part of the island. The highest concentration of microscopic sarcocysts, 1/mm2 of tissue, was observed in a 5-year old animal. Although widely distributed throughout the body, cysts were more prevalent in the tongue and diaphragm. The potential of Sarcocystis in caribou as a food-borne disease organism in man cannot be overlooked in view of its prevalence in meat and its widespread consumption, when lightly cooked, in rural Newfoundland.

Sarcocystis and sarcocystosis in India.

Sarcocystosis, in recent times has been recognized as a disease in animals and man. With the attention of scientists on this problem all over the world, work on prevalence, morphology, life cycle, transmission, pathogenesis, immunology, biochemistry and prophylaxis of this parasite has been initiated in domestic animals in India.