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Serological survey of Neospora caninum and Toxoplasma gondii in shelter-housed cats infected with feline immunodeficiency virus, Brazil
2022
Archivaldo Reche-Júnior | Alexandre Gonçalves Teixeira Daniel | Bruna Stefania Tadini | Erica Santana | Kilder Dantas Filgueira | Ronaldo Gomes Gargano | Fábio Parra Sellera | Hilda Fátima de Jesus Pena | Solange Maria Gennari
Felines play a leading role in the epidemiology of Toxoplasma gondii infection, but there is scarce information about the epidemiology of Neospora caninum, particularly in feline immunodeficiency virus (FIV)-infected cats. Cats seropositive to T. gondii do not usually show symptoms unless they are immunosuppressed, such as FIV-infected cats. The same relationship remains poorly known for N. caninum, although it has been associated with neurological disorders in HIV-infected people. Since FIV-infected cats are prone to develop encephalitis of unknown etiology, this study aimed to evaluate the presence of specific antibodies to T. gondii and N. caninum in a shelter for stray cats naturally infected with FIV. A total of 104 serum samples from cats living in a shelter, located in São Paulo city (Brazil), was assessed for T. gondii and N. caninum specific antibody by indirect fluorescent-antibody test (IFAT). Of the 104 cats, 25 (24%) were infected with FIV and, aside from these, 8 (32%) had antibodies against T. gondii (titers from 16 to 128). Only 1 (4%) of the FIV infected cats had antibodies against N. caninum, which was the first record of coinfection. Among the FIV-naïve cats, 11 (14%) were positive for T. gondii (titers from 16 to 256) and only 1 (1.2%) had antibodies against N. caninum. Serologically positive reactions to T. gondii and N. caninum were not correlated with age or sex (p>0.05), and there was no correlation between FIV and the occurrence of anti-T. gondii or anti-N. caninum antibodies (p>0.05). Further studies encompassing larger cat populations from different origins and locations are essential to clarify the prevalence of T. gondii and N. caninum antibodies in FIV-positive cats.
Mostrar más [+] Menos [-]Detection of anti-Toxoplasma gondii antibodies in wild free-living birds and mammals from the northwest region of São Paulo state, Brazil
2021
Lilian Castiglioni | Luiz Paulo Nogueira Aires | Vinícius Matheus Ferrari | Fernando Henrique Antunes Murata | Herbert Sousa Soares | Solange Maria Gennari | Juliana Giantomassi Machado | Adriana Santiago Fracischetti | Ricardo Quitério Sartori | Luiz Carlos de Mattos | Cinara Cássia Brandão | Hilda Fátima Jesus Pena
Toxoplasmosis is a protozoonosis caused by an obligate intracellular parasite named Toxoplasma gondii, which can infect humans and a large number of homeothermic animal species with worldwide distribution. The present study aimed to detect anti T. gondii antibodies from serological samples of free living wild animals from the northwest region of São Paulo state, Brazil. Thirty-two samples (eight from birds and 24 from mammals) were analyzed by the modified agglutination test (MAT) using 5 cut-off points for birds and 25 for mammals. Seropositivity was observed in 25% (2/8) of birds, including the species Rupornis magnirostris (roadside hawk) and Caracara plancus (southern caracara), and 29.2% (7/24) animals were seropositive among mammals, including one hoary fox (Lycalopex vetulus), two maned wolves (Chrysocyon brachyurus), one black howler monkey (Alouatta caraya), two crab-eating foxes (Cerdocyon thous) and one gray brocket deer (Mazama gouazoubira). The results obtained with the present study indicate the exposure to T. gondii of free-living wild animals from the northwest region of São Paulo state and, therefore, that they probably play a role in the transmission and maintenance of T. gondii in the environment they inhabit. Thus, identification of the infection in several animal species in the region indicates the environmental contamination of the area. Studies of this nature may help to understand the importance of the prevention and control of this disease in Brazil.
Mostrar más [+] Menos [-]Risk factors for Toxoplasma gondii infection in sheep in the northeastern region of Brazil
2017
Huber Rizzo | Natália Carrillo Gaeta | João Henrique Costa HORA | Jeferson da Silva Carvalho | José Wilton Pinheiro Júnior | Solange Maria Gennari | Hilda Fátima de Jesus Pena | Eliana Monteforte Cassaro Villalobos | Lilian Gregory
Toxoplasma gondii is an infective parasite that causes reproductive disorders such as abortion, fetal mummification, birth of weak offspring, and stillbirth, thereby causing economic losses to sheep production. The northeastern region of Brazil has approximately 171 million small ruminants, of which 5.4% are sheep. The present study aimed at determining the rate of occurrence of T. gondii in sheep flocks on 60 farms in 19 municipalities in the three mesoregions (eastern, semi-arid, and sertão or backlands) of the state of Sergipe, Brazil, and the risk factors associated with this infection. Serum samples were collected between 2011 and 2012, from 60 farms located in 19 municipalities in the three mesoregions: 680 in the eastern region, 280 in the semi-arid region, and 240 in the backlands, totaling 1,200 samples (990 females and 210 males). Anti-T. gondii antibodies were detected by means of the indirect fluorescence antibody test (IFAT ≥ 64). The highest occurrence was detected in the eastern region (45.3%, p = 0.001). On farms with subsistence production, the risk of having animals infected by T. gondii was approximately twice as high as on breeding/rebreeding/fattening farms (OR: 3.03; CI: 1.97-4.68). There was a significant lack of sanitary care, such as absence of a dunghill (p = 0.000; OR: 1.60; CI: 1.26-2.03), quarantine (p = 0.000; OR: 1.87; CI: 1.45-2.41) and disinfection (p = 0.003; OR: 1.46; CI: 1.13-1.88). Regarding feeding, the risk of infection was 1.74 and 1.37 times higher in places that used a trough and/or that cats could access, respectively. The presente study allows the conclusions that T. gondii is found on farms in the three mesoregions of the state of Sergipe and that environmental and management factors have an influence on sheep infection.
Mostrar más [+] Menos [-]Occurrences of antibodies against Toxoplasma gondii, Neospora spp., and Sarcocystis neurona in horses and dogs in the municipality of Pauliceia, São Paulo, Brazil
2017
Solange Oliveira | Natalia Quadros Bessa Silva | Iara Silveira | Marcelo Bahia Labruna | Solange Maria Gennari | Hilda Fátima Jesus PENA
Serum samples from 116 horses and 47 dogs from the municipality of Paulicéia, in the state of São Paulo, Brazil, were examined for anti-Toxoplasma gondii, -Neospora spp. and -Sarcocystis neurona antibodies by means of the indirect fluorescent antibody test (IFAT). The results showed that only one horse was seropositive for T. gondii (0.9%) and anti-Neospora spp. antibodies were detected in three out of the 116 horses tested (2.6%). However, 27 horses showed antibodies against S. neurona (23.8%). Amongst the serum samples from the dogs, 10 out of the 47 dogs showed antibodies against T. gondii (21.3%) and three dogs showed antibodies against Neospora caninum (6.4%). This study reports that in the municipality of Paulicéia dogs in both the rural and the urban area were exposed to T. gondii and N. caninum, while horses in the rural area were exposed to all three protozoa studied, with high occurrence of anti-S. neurona antibodies.
Mostrar más [+] Menos [-]Serological survey of Toxoplamosis in South American coatis (Nasua nasua) in Tietê Ecological Park, São Paulo, SP, Brazil
2017
Jéssica França Maia | Solange Maria Gennari | Liliane Milanelo | Haroldo Ryoiti Furuya | Vanessa Apafecida Feijó Souza | Sérgio Netto Vitaliano
Toxoplasma gondii is an obligate intracellular protozoan parasite that causes toxoplasmosis in humans, domestic animals and wild animals. Although there is serological evidence of T. gondii infection in wild animals, little is known about the role of wildlife in the epidemiological chain of this parasite. The South American coati (Nasua nasua) is an omnivorous species capable of adaptation to different environments. It can be found throughout Brazil, and in anthropized environments it can come into close contact with domestic animals. The present study found occurrences of T. gondii antibodies in South American coatis living in the Tietê Ecological Park, in the municipality of São Paulo, Brazil, through the modified agglutination test (MAT). In total, 99 samples were obtained and 70.70% (n = 70) were positive for anti-T. gondii antibodies, with titers that ranged from 50 to 3200. The data from this study indicate that South American coatis are exposed to this parasite.
Mostrar más [+] Menos [-]In vitro anti-Toxoplasma gondii efficacy of synthesised benzyltriazole derivatives
2021
Huanping Guo | Yang Gao | David D. N’Da | Xuenan Xuan
Toxoplasma gondii, an obligate intracellular parasite, is the aetiological agent of toxoplasmosis, a disease that affects approximately 25% – 30% of the world’s population. At present, no safe and effective vaccine exists for the prevention of toxoplasmosis. Current treatment options for toxoplasmosis are active only against tachyzoites and may also cause bone marrow toxicity. To contribute to the global search for novel agents for the treatment of toxoplasmosis, we herein report the in vitro activities of previously synthesised benzyltriazole derivatives. The effects of these compounds against T. gondii in vitro were evaluated by using a expressing green fluorescent protein (GFP) type I strain parasite (RH-GFP) and a type II cyst-forming strain of parasite (PruΔku80Δhxgprt). The frontline antitubercular drug isoniazid, designated as Frans J. Smit -isoniazid (FJS-INH), was also included in the screening as a preliminary test in view of future repurposing of this agent. Of the compounds screened, FJS-302, FJS-303, FJS-403 and FJS-INH demonstrated 80% parasite growth inhibition with IC50 values of 5.6 µg/mL, 6.8 µg/µL, 7.0 µg/mL and 19.8 µg/mL, respectively. FJS-302, FJS-303 and FJS-403 inhibited parasite invasion and replication, whereas, sulphadiazine (SFZ), the positive control, was only effective against parasite replication. In addition, SFZ induced bradyzoite differentiation in vitro, whilst FJS-302, FJS-303 and FJS-403 did not increase the bradyzoite number. These results indicate that FJS-302, FJS-303 and FJS-403 have the potential to act as a viable source of antiparasitic therapeutic agents.
Mostrar más [+] Menos [-]Serum anti-Toxoplasma gondii antibodies in Passer domesticus (Linnaeus, 1758) (Passeriformes: Passeridae), in the municipality of Pelotas, RS, Brazil
2020
Luciana Siqueira Silveira dos Santos | Herbert Sousa Soares | Carolina Silveira Mascarenhas | Paulo Roberto Silveira dos Santos | Solange Maria Gennari | Nara Amélia da Rosa Farias
The objective of this study was to detect the presence of anti-Toxoplasma gondii antibodies in serum samples from 100 sparrows (Passer domesticus Linnaeus, 1758) that were caught in an urban area in southern Brazil. The modified agglutination test (MAT) was used to investigate anti-T. gondii antibodies and samples with a cut-off dilution > 5 were considered positive. Among the 100 serum samples analyzed, 80 (80%) were reactive. These results demonstrate that P. domesticus may play an important role in the epidemiological chain of T. gondii, since it is widely distributed throughout Brazil, and it may act as a source of infection to domestic, semi-domestic cats and to free-living wild felids.
Mostrar más [+] Menos [-]Detection of antibodies against Sarcocystis neurona, Neospora caninum and Toxoplasma gondii in horses, dogs and cat
2019
Marilia de Oliveira Koch | Luciane Maria Laskoski | Daniel Moura de Aguiar | Bianca Ressetti da Silva | Reinaldo Ramos Régio | Juliana Ikeda Ishikura | Frederico Fontanelli Vaz | Rosangela Locatelli-Dittrich
The occurrence and distribution of antibodies against Sarcocystis neurona, Neospora caninum and Toxoplasma gondii was investigated in horses, dogs and cats from Curitiba, Paraná state, Brazil. Serum samples were selected from 100 horses, 100 dogs and 100 cats from the routine of the Veterinary Clinical Pathology Laboratory in the Veterinary Hospital of the University of Paraná (UFPR). The 100 dog samples were divided into two groups: 35 samples from dogs with neurological sign (convulsion) and 65 samples from dogs without neurological signs. The animals were adults of different breeds, males and females. Samples were analyzed by indirect fluorescent antibody test (IFAT) for protozoa S. neurona, N. caninum andT. gondii at the following cut-off dilutions: horses: 1:50, 1:50 and 1:16; dogs: 1:50, 1:50 and 1:16; cats: 1:50, 1:50 and 1:50, respectively. The obtained results were 42% of horses, 7% of dogs and 5% of cats seropositive for S. neurona; 58% of horses, 68% of dogs and 42% of cats seropositive to N. caninum, and 36% of horses, 20% of dogs and 21% of cats seropositive for T. gondii. Among the dogs with neurological signs, 8.6%, 68.6% and 25.7% were seropositive for S. neurona, N. caninum and T. gondii, respectively. Among the dogs without neurological signs, 6.2% 67.7% and 16.9% were seropositive for S. neurona, N. caninum and T. gondii, respectively. No statistical difference was found between groups of seropositive dogs for the three protozoa with neurological signs and without neurological signs. Co-infection and high antibody titers were detected. The antibodies against Sarcocystis neurona, Neospora caninum and Toxoplasma gondii were found widely distributed among horses, dogs and cats in the region of Curitiba, state of Paraná, Brazil.
Mostrar más [+] Menos [-]Occurrence of antibodies to Toxoplasma gondii in opossums caught in urban areas of Bauru, state of São Paulo, Brazil
2017
Simone Baldini Lucheis | Daniela Barbosa da Silva | Lívia Maísa Guiraldi | Wesley José dos Santos | Mirian dos Santos Paixão | Maria Fernanda Alves-Martin | Fábio Almeida Lemos | Gabriela Pacheco Sánchez | Maria Emília Bodini Santiago
Toxoplasmosis is one of the most common zoonoses worldwide. It was initially described in rodents and rabbits. There are few data on the morbidity and mortality of this disease among Brazilian marsupial fauna, such as opossums. These animals are of great importance regarding the epidemiology of this disease, given that they are prey for felids and other carnivores. With the aim of ascertaining the serological response to Toxoplasma gondii among marsupials (Didelphis spp.), 38 animals that had been caught in 14 districts of the urban area of the municipality of Bauru, state of São Paulo, were evaluated. The modified agglutination test (MAT) showed that 26.3% (10/38) of the samples analyzed were seropositive. It can be suggested that the opossums’ behavior and persistent proximity to human housing results in contact with cats and T. gondii infection, based on the frequency found in this study. This was the first study on the seroprevalence of T. gondii in opossums caught in the urban area of the municipality of Bauru, SP, and it highlights the need for environmental and health authorities of the municipality to monitor this zoonosis.
Mostrar más [+] Menos [-]Prevalence of Toxoplasma gondii in retail fresh meat products from free-range chickens in Spain
2021
Salinas, María Jesús Gracia | Campos, Cristina Escolano | Peris, María Paz Peris | Kassab, Nabil Halaihel
Toxoplasma gondii is one of the most prevalent zoonotic protozoan parasites worldwide and affects the vast majority of warm-blooded animal species, including humans. Postnatal infection in humans occurs through the ingestion of sporulated T. gondii oocysts or via the oral intake of parasite tissue cysts during the consumption of raw or undercooked meat. In this regard, given their high exposure to oocysts, chickens (Gallus domesticus) raised on the ground constitute a potential source of T. gondii. For the first time in Spain, a survey was undertaken in commercial retail free-range poultry. A total of 50 thighs from different animals were analysed. The samples were homogenised and an acid pepsin digestion procedure was applied prior to molecular analysis. Toxoplasma gondii DNA was isolated from meat by qPCR. Two sets of primers were used for DNA amplification targeting the specific sequence of a 529 bp repeat element and another set of primers was utilised for the surface antigen protein-1 gene. DNA extracted from 5 out of 50 tissue samples was positive for both genes by qPCR amplification. The 10% prevalence of Toxoplasma infection found in commercial free-range chickens raises public health issues.
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