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1.
Vet Med Sci ; 8(5): 2005-2011, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35809056

RESUMO

BACKGROUND: Toxoplasma gondii is a widespread zoonotic protozoan parasite capable of infecting all warm-blooded animals. Although the genotypes of T. gondii in pigs have been reported worldwide, there is no information on the genotypes and diversity of T. gondii in pigs in Grenada, West Indies. OBJECTIVES: The aims of the present study were to isolate, genotype and determine the diversity of T. gondii genotypes in pigs. METHODS: We carried out a modified agglutination test (MAT) on blood from 149 pig hearts collected from a local meat market. Myocardial tissue homogenate from pigs that tested positive for T. gondii was homogenized and inoculated into mice for isolation of the parasite. We collected mouse tissues and extracted DNA for genotyping based on 11 polymerase chain reaction-restriction fragment length polymorphism markers (SAG1, SAG2, alt. SAG2, SAG 3, BTUB, GRA6, L358, PK1, C22-8, C 29-2 and Apico). RESULTS: Out of the 149 pig hearts, 31 (20.8%) tested positive for T. gondii on MAT. Bioassays in mice yielded 12 isolates designated TgpgGr1 to TgpgGr12. Molecular characterisation of T. gondii revealed four genotypes as follows: ToxoDB #2-clonal type III (seven isolates); ToxoDB #7 (three isolates); ToxoDB #13 (one isolate); ToxoDB #30 (1 isolate). Overall, ToxoDB #2 was the most common (58%). Toxo database (DB) # 13, which causes interstitial pneumonia in affected mice, has also been reported. CONCLUSION: The genetic diversity of T. gondii in pigs in Grenada is lower than that in other surrounding Caribbean areas.


Assuntos
Doenças dos Roedores , Doenças dos Suínos , Toxoplasma , Toxoplasmose Animal , Animais , Anticorpos Antiprotozoários/genética , Genótipo , Granada , Camundongos , Suínos , Doenças dos Suínos/epidemiologia , Toxoplasma/genética , Toxoplasmose Animal/parasitologia
2.
Int J Parasitol Parasites Wildl ; 14: 91-96, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33537206

RESUMO

Studies on infectious and emerging diseases caused by bats have been increasing worldwide due to their well-recognised status as a reservoir species for various infectious agents as well as their close relationship to humans and animals. This study reports the molecular frequency and diversity of the parasites belonging to the Sarcocystidae family in bats in São Paulo state, Brazil. A total of 2892 tissue samples (brain and pectoral muscle/heart homogenates) from 1921 bats belonging to 36 species were collected, and the Sarcocystidae protozoan 18S ribosomal RNA encoding genes (18S rDNA) were detected by nested PCR and Sanger sequencing. The relative prevalence of Sarcocystidae species was 4.7% (91/1921) among 16 bat species, including insectivorous (n = 65), frugivorous (n = 13) and nectarivorous (n = 11) bats. From 66 sequenced positive samples, 50 were found to be suitable for analysis. Ten samples from insectivorous and nectarivorous bats showed 100% similarity with Neospora caninum (n = 1), Hammondia hammondi (n = 1), Cystoisospora canis (n = 1), Nephroisospora eptesici (n = 1), Sarcocystis (Frenkelia) glareoli (n = 1), and Toxoplasma gondii (n = 5). The 45 non-T. gondii samples revealed 15 different 18S rDNA alleles with identities varying from 96.1 to 100% with several Sarcocystidae species, which might suggest that bats can harbour a large variety of Sarcocystidae organisms. From the five T. gondii-positive tissue samples, three samples from two different bat specimens of the insectivorous Eumops glacinus were characterised using 11 PCR-restriction fragment length polymorphism (RFLP) markers, revealing the non-archetypal ToxoDB genotypes #6 (type BrI), which is one of the most prevalent in different hosts and regions from Brazil, and #69. We recommend the inclusion of T. gondii as a differential diagnosis for rabies and other neurological syndromes in bats.

3.
Front Vet Sci ; 7: 583032, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33195604

RESUMO

The apicomplexan parasite Toxoplasma gondii (T. gondii) has been found in more than 350 species of homoeothermic vertebrates in diverse climates and geographic areas. In most animals, T. gondii produces mild or asymptomatic infection. However, acute and hyperacute toxoplasmosis is associated with high mortality rates observed in Neotropical primates (NP) in captivity. These primates are distributed in 20 countries across the Americas, and although infection has been reported in certain countries and species, toxoplasmosis in the wild and its impact on NP population survival is unknown. Differences among species in exposure rates and disease susceptibility may be due in part to differences in host behavior and ecology. Four species of NP are found in Costa Rica, i.e., howler (Alouatta palliata), spider (Ateles geoffroyi), capuchin (Cebus imitator), and squirrel monkeys (Saimiri oerstedii). This study reports NP exposure to T. gondii using the modified agglutination test in 245 serum samples of NP (198 wild and 47 from captivity) from Costa Rica. Associations of serostatus with environmental (forest cover, annual mean temperature), anthropogenic (human population density), and biological (sex) variables in howler and capuchin monkeys were evaluated. The seroprevalence among wild NP was 11.6% (95% CI = 7.7-17.34), compared with 60% in captive monkeys (95% CI = 44.27-73.63), with significant differences between species (X 2 = 20.072; df = 3, p = 0.000164), suggesting an effect of behavior and ecology. In general, antibody titers were low for wild NP (<1:128) and high for captive NP (>1:8192), suggesting higher exposure due to management factors and increased life span in captivity. Seropositivity in howler monkeys was positively related to forest cover and inversely related to annual rainfall. For capuchins, annual rainfall was inversely related to seropositivity. Surveillance of T. gondii exposure in NP in captivity and in the wild is required to understand drivers of the infection and develop novel strategies to protect them.

4.
Comp Immunol Microbiol Infect Dis ; 67: 101347, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546127

RESUMO

This study aimed to genetically characterize and to determine virulence from Toxoplasma gondii samples from invasive animals in the Island of Fernando de Noronha, Brazil. Blood samples were collected from 21 tegu-lizard (Salvator merianae), 12 rock-cavies (Kerodon rupestris) and 154 black-rats (Rattus rattus) from the Island and MAT (cutoff 1:25) detected anti-T. gondii antibodies in 0% of the tegus (0/21); 58.3% of the rock-cavies (7/12) and 22.7% of rats (35/154). Tissue samples (brain, heart, liver and lung) from positive animals in MAT were collected for molecular analysis and for bioassay in Swiss Webster mice. After observation period, mice were euthanized, and serological detection and tissue cyst search in the brain were performed. The brain of positive animals for serological detection or tissue cyst search was cultured in MARC-145 cells for maintenance of the T. gondii isolate. No isolate was obtained from rock cavies. Nine isolates were obtained by bioassay of 35 seropositive black rats. DNA samples were extracted from rat tissues and from parasite isolates in cell culture, and genotyped using 10 PCR-RFLP markers. ToxoDB genotypes #78 (1) from rat tissue and #146 (4), #163 (2), #260 (2) and #291 (1) from cell culture were detected. Markers of genes ROP18 and ROP5 were analyzed and in vivo virulence test was conducted in mice. Analysis revealed two allele combinations, 3/1 and 3/3, indicating non-lethal T. gondii strains, which is supported by mouse virulence test.


Assuntos
Anticorpos Antiprotozoários/sangue , Toxoplasma/genética , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia , Animais , Encéfalo/parasitologia , Brasil/epidemiologia , Linhagem Celular , DNA de Protozoário/genética , Variação Genética/genética , Genótipo , Coração/parasitologia , Fígado/parasitologia , Lagartos/parasitologia , Pulmão/parasitologia , Camundongos , Ratos , Toxoplasma/isolamento & purificação
5.
Parasitol Res ; 118(5): 1593-1599, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30852640

RESUMO

The present study aimed to isolate and genotype strains of T. gondii from pigs slaughtered for human consumption in South Brazil. Blood and tissues (heart, diaphragm, liver, tongue, and masseter) from 400 animals were collected at two slaughterhouses. Sera were obtained, and antibodies against T. gondii were detected by both indirect fluorescence antibody test (IFAT) and modified agglutination test (MAT). The tissues of animals that tested positive in MAT, IFAT, or both (cut-off ≥ 64) were bioassayed. Twenty-six (6.5%) of the 400 animals were positive by serology. A total of 18 (69.2%) out of those 26 were positive in the mouse bioassay. The isolates were characterized by using 10 PCR-RFLP genetic markers. Fourteen isolates were fully genotyped, and four isolates were genotyped using nine of the 10 markers. All isolates belonged to ToxoDB PCR-RFLP genotype #206. The present study reports on genotype #206 in pigs for the first time, and it confirms the atypical nature of the Brazilian T. gondii isolates. Additionally, even with low levels of antibodies detected in pig herds, pork presents a T. gondii infection risk for humans.


Assuntos
Doenças Transmitidas por Alimentos/parasitologia , Doenças dos Suínos/parasitologia , Toxoplasma/genética , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/parasitologia , Matadouros , Testes de Aglutinação/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Bioensaio , Brasil , Técnica Indireta de Fluorescência para Anticorpo , Marcadores Genéticos , Variação Genética , Genótipo , Coração/parasitologia , Humanos , Fígado/parasitologia , Camundongos , Reação em Cadeia da Polimerase/veterinária , Polimorfismo de Fragmento de Restrição , Carne Vermelha/parasitologia , Suínos , Toxoplasmose Animal/sangue
6.
Infect Genet Evol ; 65: 72-79, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30030206

RESUMO

The protozoan Toxoplasma gondii is worldwide distributed showing a particular population structure that may differ among continents and countries. The aim of this study was to analyze the T. gondii population structure in Argentina and compare it with genotyping information from other South American countries. For the analysis, 39 samples from Argentina (isolates from the provinces of Buenos Aires, Misiones, Entre Ríos and San Luis) were genotyped using 10 multilocus PCR-RFLP markers including SAG1, SAG2 (5'-3'SAG2, alt. SAG2), SAG3, BTUB, GRA6, C22-8, C29-2, L358, PK1, and Apico. The T. gondii DNA samples were obtained from domestics animals (chickens n = 20; cats n = 3; pigs n = 2; goat n = 1; rabbit n = 1), humans (n = 6), zoo animals (n = 5) and a rat (n = 1). Phylogenetic relationship of these Argentinean isolates together with representative reference genotypes was determined by phylogenetic network analysis. Thirty-seven Argentinean samples belonged to 21 genotypes and two samples were genotyped at 8 of the 10 loci and considered incomplete characterized. Among these 37 typed samples, five genotypes were not previously reported. The majority of the samples grouped with the Type III (ToxoDB PCR-RFLP genotype #2) lineage. The clonal Type II (ToxoDB genotypes #1 and #3) was also identified. Our results suggest a unique population structure with combination of unique genotypes and the common Type II and Type III lineages in Argentina. Nevertheless, different regions showed distinctive pattern of genotypes, revealing a higher variability in Northern provinces.


Assuntos
Genética Populacional , Toxoplasma/classificação , Toxoplasma/genética , Toxoplasmose Animal/epidemiologia , Toxoplasmose Animal/parasitologia , Toxoplasmose/epidemiologia , Toxoplasmose/parasitologia , Animais , Argentina/epidemiologia , Genes de Protozoários , Genótipo , Geografia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Vigilância em Saúde Pública
7.
Proc Natl Acad Sci U S A ; 115(29): E6956-E6963, 2018 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-29967142

RESUMO

A majority of emerging infectious diseases in humans are zoonoses. Understanding factors that influence the emergence and transmission of zoonoses is pivotal for their prevention and control. Toxoplasma gondii is one of the most widespread zoonotic pathogens known today. Whereas only a few genotypes of T. gondii dominate in the Northern Hemisphere, many genotypes coexist in South America. Furthermore, T. gondii strains from South America are more likely to be virulent than those from the Northern Hemisphere. However, it is not clear what factor(s) shaped modern-day genetic diversity and virulence of T. gondii Here, our analysis suggests that the rise and expansion of farming in the past 11,000 years established the domestic cat/mouse transmission cycle for T. gondii, which has undoubtedly played a significant role in the selection of certain linages of T. gondii Our mathematical simulations showed that within the domestic transmission cycle, intermediately mouse-virulent T. gondii genotypes have an adaptive advantage and eventually become dominant due to a balance between lower host mortality and the ability to superinfect mice previously infected with a less virulent T. gondii strain. Our analysis of the global type II lineage of T. gondii suggests its Old World origin but recent expansion in North America, which is likely the consequence of global human migration and trading. These results have significant implications concerning transmission and evolution of zoonotic pathogens in the rapidly expanding anthropized environment demanded by rapid growth of the human population and intensive international trading at present and in the future.


Assuntos
Toxoplasma/genética , Toxoplasma/patogenicidade , Toxoplasmose/genética , Toxoplasmose/transmissão , Zoonoses/genética , Zoonoses/transmissão , Animais , Gatos , Migração Humana , Humanos , Camundongos , América do Sul , Toxoplasmose/mortalidade , Zoonoses/mortalidade
8.
J Parasitol ; 104(5): 571-573, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29986158

RESUMO

Rodents are known to be reservoir hosts of Toxoplasma gondii infection for other animals, such as cats and pigs. From February to July 2017, 167 rats ( Rattus norvegicus) were trapped in Grenada, and serum, heart, skeletal muscle, and brain were examined for T. gondii infection by serological examination (modified agglutination test, 1:25) for T. gondii antibodies and for viable parasites by bioassay in mice. Samples of heart, skeletal muscle, and brain of all rats were bioassayed in Swiss Webster (SW) outbred albino mice and interferon gamma gene knockout (KO) mice. Toxoplasma gondii was isolated from heart and brain from 1 rat; this was the only seropositive rat. The T. gondii strain was avirulent for SW mice but killed KO mice. Tissue cysts were detected in the brains of SW mice, and tachyzoites were detected in the lungs of KO mice that died of acute toxoplasmosis. The strain was propagated in cell culture, and DNA derived from cell-cultured tachyzoites was genotyped using the 10 PCR restriction fragment length polymorphisms (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico). The strain was a clonal Type III (ToxoDB genotype no. 2) strain. Although the prevalence of T. gondii in humans and animals in Grenada is high, rats seem to have little importance in the transmission of T. gondii on this island.


Assuntos
Toxoplasma/isolamento & purificação , Toxoplasmose Animal/epidemiologia , Animais , Anticorpos Antiprotozoários/sangue , Bioensaio , Encéfalo/parasitologia , Linhagem Celular , Feminino , Fibroblastos/parasitologia , Marcadores Genéticos , Granada/epidemiologia , Coração/parasitologia , Humanos , Interferon gama/genética , Perna (Membro) , Pulmão/parasitologia , Pulmão/patologia , Masculino , Camundongos , Camundongos Knockout , Músculo Esquelético/parasitologia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Ratos , Toxoplasma/imunologia
9.
Parasitol Res ; 117(3): 681-688, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29344803

RESUMO

Toxoplasma gondii is an intracellular parasite that can infect all warm-blooded animals including humans. Recent studies showed that T. gondii strains from South America are genetically diverse. The present work aimed to determine T. gondii prevalence in free-ranging chicken in northwest Parana state in Brazil by two serological tests, to isolate the parasites from seropositive chickens and to genotype the isolates. Antibodies to T. gondii in 386 serum samples from 24 farms were investigated by immunofluorescence antibody assay (IFA) and modified agglutination test (MAT). Samples having titers ≥ 16 were considered positive for both tests. Among the 386 serum samples, 102 (26.4%) were positive for IFA, 64 (16.6%) were positive for MAT, 47 (12.2%) were positive in both tests, and 119 (30.8%) were positive in at least one of the two tests. Brain and pool of heart, lung, and liver from the 119 seropositive chickens were used for mouse bioassay to isolate the parasites. Thirty eight (31.9%) of these seropositive chickens were considered positives in mouse bioassay and 18 isolates were obtained. The isolates were characterized by 10 PCR-RFLP genetic markers including SAG1, SAG2 (5'-3'SAG2, alt.SAG2), SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico. Results of genotyping were compared with the genotypes in ToxoDB database. It revealed ten genotypes, including ToxoDB PCR-RFLP genotypes #6 (n = 2), #19 (n = 1), #21 (n = 2), #111 (n = 2), #152 (n = 1), and #175 (n = 1) and four new types not described before. Our results confirmed a high genetic diversity of this parasite in southern Brazil and also showed that the use of two serological tests in combination can improve the chance of T. gondii isolation. More studies should be taken to determine the zoonotic potential of chickens in the transmission of T. gondii.


Assuntos
Galinhas/parasitologia , Doenças das Aves Domésticas/parasitologia , Toxoplasma , Toxoplasmose Animal/epidemiologia , Testes de Aglutinação/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Marcadores Genéticos , Variação Genética , Genótipo , Coração/parasitologia , Fígado/parasitologia , Pulmão/parasitologia , Camundongos , Reação em Cadeia da Polimerase/veterinária , Polimorfismo de Fragmento de Restrição , Doenças das Aves Domésticas/epidemiologia , Prevalência , Toxoplasma/genética , Toxoplasmose Animal/parasitologia
10.
Dis Aquat Organ ; 127(1): 65-69, 2017 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-29256429

RESUMO

Toxoplasma gondii is a feline protozoan reported to cause morbidity and mortality in manatees and other marine mammals. Given the herbivorous nature of manatees, ingestion of oocysts from contaminated water or seagrass is presumed to be their primary mode of infection. The objectives of this study were to investigate oocyst contamination of seagrass beds in Puerto Rico and determine the seroprevalence of T. gondii in Antillean (Trichechus manatus manatus) and Florida (T. m. latirostris) manatees. Sera or plasma from Antillean (n = 5) and Florida (n = 351) manatees were tested for T. gondii antibodies using the modified agglutination test. No T. gondii DNA was detected via PCR in seagrass samples (n = 33) collected from Puerto Rico. Seroprevalence was 0%, suggesting a lower prevalence of T. gondii in these manatee populations than previously reported. This was the first study to investigate the potential oocyst contamination of the manatee diet, and similar studies are important for understanding the epidemiology of T. gondii in herbivorous marine mammals.


Assuntos
Plantas/parasitologia , Toxoplasma , Toxoplasmose Animal/transmissão , Trichechus manatus/parasitologia , Animais , Animais Selvagens , Florida/epidemiologia , Porto Rico/epidemiologia , Toxoplasmose Animal/sangue , Toxoplasmose Animal/parasitologia , Trichechus manatus/sangue
11.
Parasit Vectors ; 10(1): 104, 2017 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-28241777

RESUMO

BACKGROUND: Toxoplasma gondii is a worldwide protozoan parasite of felids which can infect almost all warm-blooded animals, including humans. Free-roaming chickens are good indicators of environmental contamination with T. gondii oocysts because they feed from the ground. Previous research has demonstrated a high seroprevalence of T. gondii in domestic animals on St. Kitts but little is known about the genotypes circulating in the environment. METHODS: Hearts and brains from 81 free-roaming chickens in St. Kitts were digested and inoculated into 243 Swiss Webster mice in a bioassay. DNA was extracted from digested chicken tissues and the brains of all mice, and screened for T. gondii. Positive samples were genotyped using restriction fragment length polymorphism. Chicken sera were also screened for T. gondii antibodies using a modified agglutination test (MAT). RESULTS: Overall, 41% (33 out of 81) of chickens were positive for T. gondii either by serology and/or by PCR. Antibodies to T. gondii were detected by MAT in 32% (26 out of 81) of chickens, and T. gondii DNA was detected in mouse brains representing 26% (21 out of 81) of chickens. Genotyping of 21 DNA isolates, using polymorphisms at 10 loci, including SAG1, SAG2 (5'-3' SAG2 and alt.SAG2), SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico, revealed that 7 were ToxoDB genotype #141, 6 were #1 (Type II), 3 were #13, 3 were #265, one was #264 and one was #2 (Type III). Genotypes #13 and #141 appear to be more virulent. CONCLUSIONS: The results of this study highlight the greater genetic diversity of T. gondii circulating in the Caribbean region, with potentially different degrees of virulence to humans.


Assuntos
Doenças das Aves Domésticas/parasitologia , Toxoplasma/genética , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/parasitologia , Animais , Anticorpos Antiprotozoários/sangue , Galinhas , Feminino , Variação Genética , Genótipo , Camundongos , Polimorfismo Genético , Doenças das Aves Domésticas/sangue , Toxoplasma/classificação , Toxoplasmose Animal/sangue , Índias Ocidentais
12.
J Parasitol ; 103(1): 52-55, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27775481

RESUMO

The objectives of the present cross-sectional study were to isolate and genotype Toxoplasma gondii in free-range chickens from Grenada, West Indies. Using the modified agglutination test, antibodies to T. gondii were found in 39 (26.9%) of 145 free-range chickens with titers of 25 in 7 chickens, 50 in 6 chickens, 100 in 2 chickens, and 200 or higher in 24 chickens. The hearts of the 39 seropositive chickens were bioassayed in mice; viable T. gondii was isolated from 20 and further propagated in cell culture. Genotyping of T. gondii DNA extracted from cell-cultured tachyzoites using the 10 PCR-restriction fragment length polymorphism (RFLP) markers SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico revealed 4 genotypes, including ToxoDB PCR-RFLP no. 2 (Type III), no. 7, no. 13, and no. 259 (new). These results indicated that T. gondii population genetics in free-range chickens seems to be moderately diverse with ToxoDB no. 2 (Type III) as the most frequent (15/20 = 75%) compared to other genotypes in Grenada.


Assuntos
Galinhas/parasitologia , Técnicas de Genotipagem/veterinária , Polimorfismo de Fragmento de Restrição , Doenças das Aves Domésticas/parasitologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/parasitologia , Testes de Aglutinação/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Bioensaio/veterinária , Estudos Transversais , Genótipo , Granada/epidemiologia , Coração/parasitologia , Camundongos , Reação em Cadeia da Polimerase , Doenças das Aves Domésticas/epidemiologia , Estudos Soroepidemiológicos , Toxoplasma/classificação , Toxoplasma/genética , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia
13.
Infect Genet Evol ; 48: 150-155, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28028000

RESUMO

Toxoplasma gondii, a protozoan found ubiquitously in mammals and birds, is the etiologic agent of toxoplasmosis, a disease causing substantial public health burden worldwide, including about 200,000 new cases of congenital toxoplasmosis each year. Clinical severity has been shown to vary across geographical regions, with South America exhibiting the highest burden. Unfortunately, the drivers of these heterogeneities are still poorly understood, and the geographical origin and historical spread of the pathogen worldwide are currently uncertain. A worldwide sample of 168 T. gondii isolates gathered in 13 populations was sequenced for five fragments of genes (140 single nucleotide polymorphisms from 3153bp per isolate). Phylogeny based on Maximum likelihood methods with estimation of the time to the most recent common ancestor (TMRCA) and geostatistical analyses were performed for inferring the putative origin of T. gondii. We show that extant strains of the pathogen likely evolved from a South American ancestor, around 1.5 million years ago, and reconstruct the subsequent spread of the pathogen worldwide. This emergence is much more recent than the appearance of ancestral T. gondii, believed to have taken place about 11 My ago, and follows the arrival of felids in this part of the world. We posit that an ancestral lineage of T. gondii likely arrived in South America with felids and that the evolution of oral infectivity through carnivorism and the radiation of felids in this region enabled a new strain to outcompete the ancestral lineage and undergo a pandemic radiation.


Assuntos
Doenças do Gato/parasitologia , Toxoplasma/genética , Toxoplasmose Animal/parasitologia , Animais , Doenças do Gato/epidemiologia , Gatos , Evolução Molecular , Genes de Protozoários , Especiação Genética , Variação Genética , Humanos , Filogenia , Filogeografia , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , América do Sul/epidemiologia , Toxoplasmose/epidemiologia , Toxoplasmose/parasitologia , Toxoplasmose Animal/epidemiologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-27074322

RESUMO

The role of rodents in the epidemiology of toxoplasmosis was investigated in Londrina, Paraná State, Brazil. One hundred and eighty-one Rattus rattus and one Mus musculus were caught in 37 places. Blood and tissues were collected and submitted to the indirect fluorescence antibody test (IFAT) and the bioassay. Serum samples from 61 contacting dogs were also collected. Sixteen rats (8.8%) were positive for Toxoplasma gondii, but just two of them were positive by serology and bioassay test. Antibodies were found in nine (4.9%) rats. Tissues of nine rats bioassayed were positive and four isolates were obtained. Restriction fragment length polymorphism (RFLP) analysis was performed using 12 markers (SAG1, SAG2, SAG2-alt, C22-8, C29-2, L358, PK1, BTUB, GRA6, SAG3, Apico, CS3). Genotyping revealed that the four strains isolated from this study have been isolated before in cats and chickens from Brazil. None of the isolates was identified like clonal archetypal T-types I, II, and III. The rats presented lower serologic Toxoplasma gondii prevalence (8.8%) compared to contacting dogs (70.5%).


Assuntos
Anticorpos Antiprotozoários/sangue , Doenças do Cão/parasitologia , Ratos/parasitologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/parasitologia , Animais , Brasil/epidemiologia , Gatos , Doenças do Cão/epidemiologia , Cães , Técnica Indireta de Fluorescência para Anticorpo , Genótipo , Camundongos , Polimorfismo de Fragmento de Restrição , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia
15.
Parasitol Res ; 115(4): 1627-34, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26762861

RESUMO

Little is currently known of clinical toxoplasmosis in humans and animals in the Caribbean. We investigated the prevalence of IgG and IgM antibodies in 437 pregnant women from 10 English speaking Caribbean countries. Overall, antibodies (IgG) to Toxoplasma gondii (modified agglutination test, MAT, cut-off 1:6) were found in 174 (39.8 %) of 437 human sera; specifically 12 of 38 from Antigua-Barbuda, 26 of 52 from Belize, 9 of 50 from Bermuda, 29 of 49 from Dominica, 18 of 49 from Grenada, 16 of 47 from Jamaica, 5 of 15 from Montserrat, 8 of 44 from St. Kitts/Nevis, 24 of 45 from St. Lucia, and 27 of 50 from St. Vincent/Grenadines were seropositive. All IgG-positive sera were tested for IgM antibodies using the immunocapture method; all sera were negative for IgM antibodies. Additionally, tissues and sera of 45 dogs from St. Kitts were examined for T. gondii infection. Antibodies (IgG, MAT, 1:≥25) were found in 19 (42.2 %) of 45 dogs. Muscle samples (tongue, leg) of 19 seropositive dogs were digested in pepsin, and homogenates were bioassayed in mice. Viable T. gondii were isolated from 6 dogs. T. gondii isolates were further propagated in cell culture. PCR-RFLP genotyping of cell culture derived tachyzoites using 10 genetic markers, SAG1, SAG2 (5' and 3' SAG2, and alt.SAG2) SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico revealed that 4 isolates were ToxoDB PCR-RFLP genotype #2, and 2 were new genotypes #264 and #265. Review of 22 viable T. gondii isolates from chickens, dogs, and cats from Grenada and St. Kitts revealed that 1 isolate was type II, 13 were type III, and 8 were atypical. Thus, type III strains were predominant. Overall, the study revealed high prevalence of T. gondii in the Caribbean islands.


Assuntos
Anticorpos Antiprotozoários/imunologia , Doenças do Cão/epidemiologia , Variação Genética , Toxoplasma/imunologia , Toxoplasmose/epidemiologia , Animais , Gatos , Galinhas , Doenças do Cão/parasitologia , Cães , Feminino , Marcadores Genéticos/genética , Genótipo , Humanos , Camundongos , Gravidez , Estudos Soroepidemiológicos , Toxoplasma/genética , Toxoplasma/isolamento & purificação , Toxoplasmose/parasitologia , Índias Ocidentais/epidemiologia
16.
Front Microbiol ; 6: 181, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25806028

RESUMO

Considering that Toxoplasma gondii has shown high genetic diversity in Brazil, the aim of this study was to determine whether Calomys callosus chronically infected by the ME-49 strain might be susceptible to reinfection by these Brazilian strains, including vertical transmission of the parasite. Survival curves were analyzed in non-pregnant females chronically infected with ME-49 and reinfected with the TgChBrUD1 or TgChBrUD2 strain, and vertical transmission was analyzed after reinfection of pregnant females with these same strains. On the 19th day of pregnancy (dop), placentas, uteri, fetuses, liver, spleen, and lung were processed for detection of the parasite. Blood samples were collected for humoral and cellular immune response analyses. All non-pregnant females survived after reinfection and no changes were observed in body weight and morbidity scores. In pregnant females, parasites were detected in the placentas of ME-49 chronically infected females and reinfected females, but were only detected in the fetuses of reinfected females. TgChBrUD2 reinfected females showed more impaired pregnancy outcomes, presenting higher numbers of animals with fetal loss and a higher resorption rate, in parallel with higher levels of pro-inflammatory cytokines and IgG2a subclass antibodies. Vertical transmission resulting from chronic infection of immunocompetent C. callosus is considered a rare event, being attributed instead to either reactivation or reinfection. That is, the pregnancy may be responsible for reactivation of the latent infection or the reinfection may promote T. gondii vertical transmission. Our results clearly demonstrate that, during pregnancy, protection against T. gondii can be breached after reinfection with parasites belonging to different genotypes, particularly when non-clonal strains are involved in this process and in this case the reinfection promoted vertical transmission of both type II and Brazilian T. gondii strains.

17.
Rev Bras Parasitol Vet ; 23(4): 443-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25517521

RESUMO

Eared doves (Zenaida auriculata), which are common in urban, rural and wild areas in many regions of Brazil, are frequently prey for domestic cats. Therefore Toxoplasma gondii isolates obtained from doves may reflect greater environmental diversity than those from other hosts. The aim of the present study was to evaluate T. gondii seroprevalence, isolate and genotype strains from Z. auriculata. Serum and tissue samples were collected from 206 doves for use in the modified agglutination test (MAT) and mouse bioassay. The prevalence of T. gondii antibodies in the doves was 22.3% (46/206), with titers ranging from 16 to 4096, and T. gondii strains were isolated from 12 of these doves. Five genotypes were detected by means of PCR-RFLP, including ToxoDB genotypes #1, #6, #17 and #65, and one genotype that had not previously been described (ToxoDB#182). This was the first report on isolation of T. gondii from Z. auriculata. This study confirmed the genetic diversity of T. gondii isolates and the existence of clonal type II (ToxoDB genotype #1) in Brazil.


Assuntos
Anticorpos Antiprotozoários/sangue , Doenças das Aves/parasitologia , Columbidae/sangue , Columbidae/parasitologia , Toxoplasma/genética , Toxoplasma/imunologia , Toxoplasmose Animal/sangue , Animais , Doenças das Aves/epidemiologia , Brasil/epidemiologia , Feminino , Masculino , Estudos Soroepidemiológicos , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/epidemiologia
18.
R. bras. Parasitol. Vet. ; 23(4): 443-448, Oct-Dec/2014. tab
Artigo em Inglês | VETINDEX | ID: vti-27269

RESUMO

Eared doves (Zenaida auriculata), which are common in urban, rural and wild areas in many regions of Brazil, are frequently prey for domestic cats. Therefore Toxoplasma gondii isolates obtained from doves may reflect greater environmental diversity than those from other hosts. The aim of the present study was to evaluate T. gondii seroprevalence, isolate and genotype strains from Z. auriculata. Serum and tissue samples were collected from 206 doves for use in the modified agglutination test (MAT) and mouse bioassay. The prevalence of T. gondii antibodies in the doves was 22.3% (46/206), with titers ranging from 16 to 4096, and T. gondii strains were isolated from 12 of these doves. Five genotypes were detected by means of PCR-RFLP, including ToxoDB genotypes #1, #6, #17 and #65, and one genotype that had not previously been described (ToxoDB#182). This was the first report on isolation of T. gondii from Z. auriculata. This study confirmed the genetic diversity of T. gondii isolates and the existence of clonal type II (ToxoDB genotype #1) in Brazil.


Pombos silvestres (Zenaida auriculata), comuns em áreas urbanas, rurais e selvagens em muitas regiões do Brasil, são frequentemente predados por gatos domésticos. Sendo assim, os isolados de T. gondii obtidos de pombos podem refletir uma maior diversidade ambiental do que os outros hospedeiros. O objetivo do presente estudo foi avaliar a soroprevalência, isolar e genotipar T. gondii de Z. auriculata. Amostras de soro e tecido foram coletadas de 206 pombos para o teste de aglutinação modificado (MAT) e o bioensaio em camundongos. A prevalência de anticorpos contra T. gondii em pombos foi 22,3% (46/206), com títulos variando de 16 a 4096, e T. gondii foi isolado de 12 pombos. Cinco genótipos foram detectados por PCR-RFLP, incluindo os genótipos ToxoDB #1, #6, #17, #65 e um genótipo não descrito anteriormente (ToxoDB#182). Esse é o primeiro relato de isolamento de T. gondii de Z. auriculata. Este estudo também confirmou a diversidade dos isolados de T. gondii e a presença de tipo clonal II (ToxoDB #1) no Brasil.


Assuntos
Animais , Camundongos , Ferro/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Óxido Nítrico/farmacologia , Fagossomos/efeitos dos fármacos , Fagossomos/metabolismo , Complexo Antígeno-Anticorpo/metabolismo , Células Cultivadas , Compostos Férricos/metabolismo , Ferritinas/metabolismo , Camundongos Knockout , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase/deficiência , Óxido Nítrico Sintase/genética , Óxido Nítrico/metabolismo , Transferrina/imunologia , Transferrina/metabolismo
19.
Rev. bras. parasitol. vet ; 23(4): 443-448, Oct-Dec/2014. tab
Artigo em Inglês | LILACS | ID: lil-731244

RESUMO

Eared doves (Zenaida auriculata), which are common in urban, rural and wild areas in many regions of Brazil, are frequently prey for domestic cats. Therefore Toxoplasma gondii isolates obtained from doves may reflect greater environmental diversity than those from other hosts. The aim of the present study was to evaluate T. gondii seroprevalence, isolate and genotype strains from Z. auriculata. Serum and tissue samples were collected from 206 doves for use in the modified agglutination test (MAT) and mouse bioassay. The prevalence of T. gondii antibodies in the doves was 22.3% (46/206), with titers ranging from 16 to 4096, and T. gondii strains were isolated from 12 of these doves. Five genotypes were detected by means of PCR-RFLP, including ToxoDB genotypes #1, #6, #17 and #65, and one genotype that had not previously been described (ToxoDB#182). This was the first report on isolation of T. gondii from Z. auriculata. This study confirmed the genetic diversity of T. gondii isolates and the existence of clonal type II (ToxoDB genotype #1) in Brazil.


Pombos silvestres (Zenaida auriculata), comuns em áreas urbanas, rurais e selvagens em muitas regiões do Brasil, são frequentemente predados por gatos domésticos. Sendo assim, os isolados de T. gondii obtidos de pombos podem refletir uma maior diversidade ambiental do que os outros hospedeiros. O objetivo do presente estudo foi avaliar a soroprevalência, isolar e genotipar T. gondii de Z. auriculata. Amostras de soro e tecido foram coletadas de 206 pombos para o teste de aglutinação modificado (MAT) e o bioensaio em camundongos. A prevalência de anticorpos contra T. gondii em pombos foi 22,3% (46/206), com títulos variando de 16 a 4096, e T. gondii foi isolado de 12 pombos. Cinco genótipos foram detectados por PCR-RFLP, incluindo os genótipos ToxoDB #1, #6, #17, #65 e um genótipo não descrito anteriormente (ToxoDB#182). Esse é o primeiro relato de isolamento de T. gondii de Z. auriculata. Este estudo também confirmou a diversidade dos isolados de T. gondii e a presença de tipo clonal II (ToxoDB #1) no Brasil.


Assuntos
Animais , Camundongos , Ferro/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Óxido Nítrico/farmacologia , Fagossomos/efeitos dos fármacos , Fagossomos/metabolismo , Complexo Antígeno-Anticorpo/metabolismo , Células Cultivadas , Compostos Férricos/metabolismo , Ferritinas/metabolismo , Camundongos Knockout , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase/deficiência , Óxido Nítrico Sintase/genética , Óxido Nítrico/metabolismo , Transferrina/imunologia , Transferrina/metabolismo
20.
Trans R Soc Trop Med Hyg ; 108(4): 244-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24554488

RESUMO

BACKGROUND: Toxoplasma gondii populations that perpetuate in South America's natural ecosystems display broad genetic diversity, but the impact of this diversity on humans is generally unknown. In this short communication, we depict the genotypic traits of four isolates related to congenital parasitism as it emerges in Southern Brazil. METHODS: Using the PCR-restriction fragment length polymorphism markers SAG1, 5'3'SAG2, alt. SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico, and CS3. Three of the four strains (TgCTBral, TgCTBrv, and TgCTBrac) were identified as ToxoDB genotype #166. RESULTS: Three children displayed normal cognitive/psychomotor development, and one child displayed Sabin's tetrad (TgCTBral). CONCLUSION: Vertical transmission of the two genotypes was observed and contributes to knowledge of T. gondii strains isolated from humans in Brazil.


Assuntos
Toxoplasma/genética , Toxoplasmose/parasitologia , Adulto , Brasil , Criança , Transtornos Cognitivos/etiologia , DNA de Protozoário/genética , Deficiências do Desenvolvimento/etiologia , Feminino , Seguimentos , Marcadores Genéticos , Variação Genética , Genótipo , Humanos , Transmissão Vertical de Doenças Infecciosas , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , Gravidez , Complicações Parasitárias na Gravidez/parasitologia , Toxoplasma/isolamento & purificação , Toxoplasmose/complicações , Toxoplasmose/transmissão
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