Negative seroprevalence for Toxoplasma gondii in free-living primates from Central Amazonia.

This study presents 35 negative serologies for antibodies anti-T. gondii in free-living primates from Central Amazonia. Our results suggest that these populations have not had contact with the parasite and, therefore, do not have antibodies. This was the first study surveying T. gondii in Cacajao, Callicebus, Pithecia, and Saguinus monkeys.

Serosurvey of spotted fever group Rickettsia in equids from western Pará, Amazon, Brazil.

From a previous large epidemiological survey, we randomly selected 474 serum samples (463 horses and 11 mules) distributed among four municipalities of Pará state, Amazon region, Brazil, and from three types: farm animal, urban carthorse, and sport horse. Samples were tested by indirect fluorescence antibody test (IFAT ≥ 64) for antibodies reactive to spotted fever group (SFG) rickettsiae using Rickettsia rickettsii as crude antigens. From the 474 equids tested, 149 (31.4%) had ticks attached during sampling, belonging mostly to the species Dermacentor nitens. The overall seroprevalence for SFG rickettsiae was 31.4% (95% confidence interval: 27.3-35.9%) with 149 seropositive animals out of 474 screened. Notably, 77 equids (16.2%) had high endpoint titers ranging from 512 to 16,384, indicating that they had been exposed to SFG rickettsiae not long before sampling. Animal type affected rickettsial seroprevalence, with significantly higher values among farm horses when compared with urban and sport animals. Presence of dogs and tick infestation were negatively associated with equid seropositivity to R. rickettsii. This is the first report of SFG rickettsiae-reactive antibodies in equids from Pará state, Brazilian Amazon.

Toxoplasma gondii isolated from a Brazilian patient with rare pulmonary toxoplasmosis has a novel genotype and is closely related to Amazonian isolates.

Pulmonary toxoplasmosis is rare in immunocompetent patients. Herein, a Toxoplasma gondii strain isolated in Brazil from an immunocompetent patient who had severe pulmonary involvement was biologically and molecularly characterized for the first time. The TgHumIMTBr1 isolate was bioassayed in mice showing a virulent phenotype. Restriction fragment length polymorphism (RFLP) genotyping using 11 markers [SAG1, SAG2 (5´3´SAG2 and alt. SAG2), SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico and CS3] revealed a new non-archetypal genotype assigned as #312. Genotyping using ROP18/ROP5 markers exhibited the virulent combination of alleles 4 and 1. Microsatellite analysis using 15 markers (TUB2, W35, TgM-A, B18, B17, M33, IV.1, X1.1, N60, N82, AA, N61, N83, M48 and M102) revealed an atypical genotype with three unique alleles and a rare combination of alleles 246 (W35) and 203 (TgM-A) that is typical of the Amazon region. Non-archetypal genotypes with unique alleles may function in the occurrence of severe toxoplasmosis in immunocompetent patients in Brazil. Attempts to isolate or molecularly detect T. gondii for further genotyping studies would contribute to the understanding of causes related to the severity of toxoplasmosis in immunocompetent patients.

The impact of dry ageing vacuum-packed pork on the viability of Toxoplasma gondii tissue cysts.

The present study evaluated the viability of Toxoplasma gondii tissue cysts in dry-aged pork loins (m. longissimus) after 14, 21 and 28 days under controlled temperature (0 °C ±â€¯1 °C). The pigs (n = 9) were orally inoculated with 3,000 T. gondii oocysts. The right loin of each pig was aged for a predetermined period, and the left loin was kept unprocessed as a control. Two experiments were performed. In Experiment 1, the loins of three pigs were aged for 14 days and then bioassayed in both cats and mice. In Experiment 2, the loins of six pigs were bioassayed only in mice, and the ageing periods were 14, 21, and 28 days. Toxoplasma gondii tissue cysts remained viable in loins aged up to 14 days, as confirmed by bioassays in cats and mice. Viable T. gondii was not recovered by bioassays in mice from loins that were aged for 21 or 28 days. These results demonstrate that T. gondii remained viable in vacuum-packed dry-aged pork loins for 14 days at controlled temperature but not for 21 days or longer.

Isolation of viable Toxoplasma gondii from organs and Brazilian commercial meat cuts of experimentally infected pigs.

The present study evaluated the distribution and viability of Toxoplasma gondii tissue cysts in the organs and Brazilian commercial cuts of experimentally infected pigs. The pigs were infected with 3 × 103 oocysts of the T. gondii isolate TgCkBr57 (Type BrII). Mouse bioassays were performed on the brain, retina, tongue, diaphragm, and heart as well as the following muscle cuts: loin (longissimus), coppa (longissimus, spinalis dorsi, rhomboideus), tenderloin (psoas major), outside flat (biceps femoris), topside (semimembranosus), and top sirloin (gluteus medius). Toxoplasma gondii was isolated from the coppa, heart, diaphragm, and tongue of three pigs; from the tenderloin, outside flat, and brain of two pigs; and from the top sirloin and loin of one pig. Thus, the viability of T. gondii cysts was observed in all of the organs and cuts evaluated (except for the topside and retina), demonstrating the broad distribution of this parasite in pig organs and commercial meat cuts, and the importance of this species as a source of human infection.

Outbreak of toxoplasmosis in a flock of domestic chickens (Gallus gallus domesticus) and guinea fowl (Numida meleagris).

Toxoplasmosis is a disease with a worldwide distribution that affects a wide variety of animal species, though with rare descriptions in chickens. We describe the clinical, epidemiological, pathological, and molecular aspects of a toxoplasmosis outbreak in domestic chickens and guinea fowl in southern Brazil. The flock was composed of 47 domestic chickens and 29 guinea fowl. Of these, 22 birds showed clinical signs of lethargy, anorexia, and neurological signs over a clinical course of 24-72 h, and 15 died. Epidemiological data were obtained through fieldwork performed at the chicken farm and necropsies of six birds. Gross lesions were absent at necropsy, and histopathological findings included inflammatory infiltrate of macrophages, lymphocytes, and plasma cells and necrosis in several tissues associated with intralesional Toxoplasma gondii. Immunohistochemistry for T. gondii was positive. Additionally, restriction fragment length polymorphism (RFLP) analysis with 11 markers (SAG1, SAG2 (5'3'SAG2 and alt. SAG2), SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico, and CS3) and microsatellite (MS) analysis with 15 markers (TUB2, W35, TgMA, B18, B17, M33, IV.1, XI.1, N60, N82, AA, N61, N83, M48, and M102) were performed. PCR-RFLP revealed T. gondii genotype ToxoDB-PCR-RFLP #280, and MS analysis also showed a unique genotype. This is the first description of this genotype in chickens and adds to the evidence suggesting considerable genotypic diversity of T. gondii in Brazil.

Typical Brazilian genotype of Toxoplasma gondii isolated from a horse destined for human consumption in Europe from a slaughterhouse.

Toxoplasmosis is a zoonotic disease caused by the protozoan Toxoplasma gondii. Infections occur via the ingestion of oocysts, consumption of cysts containing bradyzoites, and transplacental transmission of tachyzoites. Diversity in T. gondii strains may affect the outcome of clinical toxoplasmosis. The consumption of horse meat is a common practice in some parts of the world. The objectives of the present study were to isolate and genotype T. gondii from horses from an abattoir in the state of Rio Grande do Sul in southern Brazil that exports horse meat to Europe. Antibodies to T. gondii were found in 32.5% (13/40) of the horses using the modified agglutination test (MAT) with a cut-off of 1:25. Tissues from the 13 seropositive horses were bioassayed in mice, and one isolate, designated TgHorseBrRS1, was obtained. PCR-RFLP of the isolate revealed the ToxoDB-RFLP #228 genotype, a typical non-archetypal Brazilian genotype, and microsatellite analysis showed a unique non-archetypal genotype. This study showed that horses from Brazil can harbor viable T. gondii in their tissues, suggesting that recommendations to consumers should be made, especially in European countries where consumption of raw horse meat is common.

Amblyomma ticks infesting amphibians and Squamata reptiles from the lower Amazon region, Brazil.

Amphibians and Squamata reptiles belonging to a zoological collection were screened for ectoparasites, which were removed from the hosts and identified using morphological keys. Descriptive statistics and analysis of the association between the parasite and host characteristics (taxonomic group, capture location and habitat) were done. Among the 1256 animals examined (319 amphibians and 937 reptiles), 86 individuals were parasitized, corresponding to a frequency of 6.9% (6.6% reptiles and 7.5% amphibians). Ticks in the adult and nymph stages were identified to the species level; all of them belonged to the species Amblyomma dissimile. The larvae were identified to the genus level and were all Amblyomma sp. In total 69 larvae, 28 nymphs and eight adults were found. The most parasitized species was the frog Rhinella major: 24 parasitized animals of 65 examined (36.9%). There was a difference (P < 0.001) between parasitism by ticks of the genus Amblyomma with regard to the habitat of capture of the parasitized animal, with a higher parasitism rate in hosts that inhabited open areas as compared to animals ensconced in forest areas and edges of forests. New tick-host associations are given.

NEOSPORA CANINUM-SPECIFIC ANTIBODIES IN FREE-RANGING WHITE-LIPPED PECCARIES ( TAYASSU PECARI) FROM THE PERUVIAN AMAZON: DETECTION OF ANTIBODIES IN SERUM AND EVALUATION OF INDIRECT FLUORESCENT ANTIBODY TEST WITH HETEROLOGOUS SECONDARY ANTIBODY.

Neospora caninum is a coccidian parasite originally reported in dogs and widely prevalent in numerous species of wild and domestic animals and has as definitive hosts some species of canids. The white-lipped peccary (WLP) ( Tayassu pecari) is a Tayassuidae mammal, found from Mexico to south of Brazil and north of Argentina. It is a game species with great economic importance in the Peruvian Amazon. Blood samples from 101 WLPs were collected from near or within three different conservation reserves located in the southeastern region of the Peruvian Amazon. For the detection of antibodies against N. caninum, indirect fluorescent antibody tests (IFAT) were performed using collared peccary ( Pecari tajacu) and swine ( Sus scrofa domesticus) heterologous secondary antibodies. For both IFAT tests, the cutoff was 1:50. Positive samples were titrated by a two fold serial dilution. In addition to IFAT, samples were also analyzed using an immunoblotting test (IB) with anti-swine conjugate. To confirm the viability of the anti-swine conjugate, the results of these samples previously tested by a modified agglutination test (MAT) for Toxoplasma gondii were used as reference. From the total of 101 samples tested, 5 (4.9%) were N. caninum positive by the three tests and an extra sample was positive by both IFATs and negative in the IB. Comparing both IFATs and considering IB as the gold standard, the relative sensitivity of IFATs was 100%, the specificity was 98.9%, the positive predictive value was 83.3%, and the negative predictive value was 100%. The agreement between tests was characterized by a κ value of 0.904 (95% confidence interval, 0.717 to 1.0) and an SE of 0.095. This is the first report of N. caninum antibodies in free-ranging T. pecari, and swine and collared peccary conjugate can be used as a secondary antibody for detection of antibodies in Tayassu species.

ANTIBODIES AGAINST BRUCELLA ABORTUS AND LEPTOSPIRA SPP. IN CAPTIVE MAMMALS IN THE STATES OF PARá AND RIO GRANDE DO NORTE, BRAZIL.

Brazil has a large variety of wild animal species, but limited data are available on the occurrence of Brucella abortus and Leptospira spp. antibodies in these animals. Sera from 141 captive mammals belonging to 11 different species from the Northern and Northeastern regions of Brazil were screened. Antibodies against B. abortus and Leptospira spp. (24 live serovars) were investigated using the Rose Bengal plate and microscopic agglutination tests, respectively. Associations between the age, gender, and place of captivity were analyzed using the Pearson chi-square or the Fisher exact test. None of the animals were antibody positive for B. abortus. Among the animals tested, 11 (7.8%) were seropositive for Leptospira spp. These included one red brocket deer ( Mazama americana), two tufted capuchin ( Sapajus apella), seven agoutis ( Dasyprocta aguti), and one lowland paca ( Cuniculus paca). No association was observed between sex, age, and the occurrence of Leptospira spp. antibodies ( P > 0.05). However, an association was observed according to the place of captivity ( P = 0.046). From these 11 positive animals, six (54.5%) reacted to the serovars from the Icterohaemorraghiae serogroup, which is mainly responsible for the clinical cases of human leptospirosis in Brazil. To our knowledge, this is the first report of Leptospira spp. antibodies in M. americana and C. paca.

Detection of Toxoplasma gondii antibodies in captive non-human primates in the Amazon region, Brazil.

BACKGROUND: Toxoplasma gondii infections in captive non-human primates are of interest because often they die due to severe toxoplasmosis. Thus, we aimed to evaluate samples from a serum bank to T. gondii antibodies. METHODS: Serum samples of 179 monkeys from the National Center of Primates, Brazil, were retrospective analyzed for T. gondii IgG antibodies by modified agglutination test using formalin-fixed whole parasites as antigen (cutoff 1:25). RESULTS: Among the 179 samples tested, 88 (49.2%) were positive. Twelve of the 18 evaluated species presented at least one positive animal. A higher occurrence of positive animals was found in New World (52.2%) than Old World (22.2%) monkeys (P = .023) and in the animals from domestic donation origin, which had lived in human homes as pets (P = .004). CONCLUSIONS: We confirm the widespread presence of T. gondii in captive monkeys and contribute to the range of species that can be infected by this parasite.

Isolation and biological and molecular characterization of Neospora caninum (NC-SP1) from a naturally infected adult asymptomatic cattle (Bos taurus) in the state of São Paulo, Brazil.

The biological and genetic diversity of Neospora caninum is very limited because of availability of only a few viable isolates worldwide. This study describes the isolation and biological and molecular characterization of a new viable isolate of N. caninum (NC-SP1), from a cattle in Brazil. Approximately 400 g of brain from a naturally infected adult male cattle from an abattoir was fed to a 2-month-old dog. Neospora-like oocysts were observed on day 7 post-inoculation (PI) and the duration of oocyst shedding was 14 days. The DNA obtained from oocysts was characterized molecularly and the final sequence was 99% identical to homologous sequences of N. caninum available in GenBank®. For bioassay, gerbils (Meriones unguiculatus) were orally inoculated with 10 100 and 1000 oocysts; all gerbils remained clinically normal but developed N. caninum antibodies 14 days PI. Cell culture isolation was successful using the brain homogenate from one of the gerbils and tachyzoites were observed 24 days PI. Microsatellite genotyping revealed a unique genetic profile for this new reference isolate.

Rare case of acute toxoplasmosis in a domestic rabbit (Oryctolagus cuniculus) in Brazil associated with the type BrIII Brazilian clonal lineage of Toxoplasma gondii.

Toxoplasmosis is a widely distributed disease that infects birds and mammals, including humans. Acute clinical course of toxoplasmosis is considered to be rare among domestic rabbits (Oryctolagus cuniculus). The aim of this study was to present the first report of fatal acute disease caused by Toxoplasma gondii type BrIII genotype, a typical Brazilian clonal lineage, in a domestic rabbit. T. gondii was identified in histological sections of spleen and liver tissue, and these tissues were also immunohistochemically positive for T. gondii. After the histopathological and immunohistochemical confirmation of T. gondii, the genotype of this pathogen was determined via PCR-RFLP with 11 markers (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico, and CS3) and via microsatellite (MS) analysis with 15 markers (TUB2, W35, TgMA, B18, B17, M33, IV.1, X1.1, M48, M102, N60, N82, AA, N61, and N83). This study shows that type BrIII genotype, circulating in Brazil in different hosts, can cause acute disease in a naturally infected animal host. The described case also involves the first reported occurrence of the 291 allele for the typing marker TUB2 in a type BrIII strain, emphasizing the genetic diversity of T. gondii in Brazil.

First report of typical Brazilian Toxoplasma gondii genotypes from isolates of free-range chickens (Gallus gallus domesticus) circulating in the state of Paraíba, Northeast Brazil.

This study evaluated, for the first time, the genetic diversity of Toxoplasma gondii isolates from free-range chickens from the state of Paraíba, Northeast Brazil. Tissue samples from 33 chickens from properties in five municipalities of Paraíba (Esperança, Olho d'Água, Malta, Monteiro, and Patos) were bioassayed in mice. The brains of mice infected with T. gondii cysts were used for DNA extraction and genotyping. Genotyping was performed using 11 PCR-RFLP markers and 15 microsatellite (MS) markers. Complete genotyping results were obtained for 29 isolates, with nine genotypes detected by RFLP and 15 genotypes identified by MS. Three genotypes (#273, #274, and #277) have only been recently identified from pigs in the region. Brazilian clonal types BrII and BrIII were identified from one isolate each. Clonal types I, II, and III were not detected by RFLP. Genotype #13 (Caribbean 1), detected in 48.3% (14/29) of isolates from four of the five municipalities investigated, was the most prevalent genotype in the state of Paraíba. However, the MS analysis showed that of these 14 isolates, only four were unique genotypes, and considering the distance between the municipalities from where they were collected, it is possible that only seven are independent isolates while the others are clones. The other genotypes were restricted to different microregions. The results indicate that the Caribbean 1 lineage of T. gondii is circulating widely in Northeast Brazil. The genotypic diversity of T. gondii in the state of Paraíba is high, and microsatellite analysis revealed this diversity with higher resolution than PCR-RFLP.

Sero-epidemiological survey for brucellosis, leptospirosis, and toxoplasmosis in free-ranging Alouatta caraya and Callithrix penicillata from São Paulo State, Brazil.

BACKGROUND AND METHODS: Sera were tested for Brucella spp., Leptospira spp. and Toxoplasma gondii antibodies in 68 free-ranging New World monkeys from a forest fragment of the Brazilian Cerrado. RESULTS AND CONCLUSION: All animals were negative for Brucella spp. and Leptospira spp. However, 75% of Alouatta caraya and 16.6% of Callithrix penicillata were positive for T. gondii. The implications for conservation and health management are discussed.

Candidatus Rickettsia andeanae, a spotted fever group agent infecting Amblyomma parvum ticks in two Brazilian biomes.

Adult ticks of the species Amblyomma parvum were collected from the vegetation in the Pantanal biome (state of Mato Grosso do Sul) and from horses in the Cerrado biome (state of Piauí) in Brazil. The ticks were individually tested for rickettsial infection via polymerase chain reaction (PCR) targeting three rickettsial genes, gltA, ompA and ompB. Overall, 63.5% (40/63) and 66.7% (2/3) of A. parvum ticks from Pantanal and Cerrado, respectively, contained rickettsial DNA, which were all confirmed by DNA sequencing to be 100% identical to the corresponding fragments of the gltA, ompA and ompB genes of Candidatus Rickettsia andeanae. This report is the first to describe Ca. R. andeanae in Brazil.

Pathogenicity of Nc-Bahia and Nc-1 strains of Neospora caninum in experimentally infected cows and buffaloes in early pregnancy.

Neospora caninum is a protozoan parasite known as an important cause of bovine abortion worldwide. Little is currently known about how different strains of N. caninum vary in their pathogenicity. In this study, we compared a Brazilian strain, Nc-Bahia, with the first isolate of this coccidian, Nc-1. Eight cows and seven buffaloes were submitted to fixed-time artificial insemination protocols for a better control of pregnancy. Group 1 was inoculated with Nc-Bahia (n = 8; five cows and three buffaloes), and Group 2 was inoculated with Nc-1 (n = 5; two cows and three buffaloes). One nonpregnant female of each species was left uninfected as sentinel controls for potential environmental infection. All inoculated animals received 5 × 10(8) tachyzoites of N. caninum, by intravenous route, on the 70th day of gestation. Uninfected animals remained seronegative throughout the experiment, indicating no exogenous infection, whereas all inoculated animals became seropositive to N. caninum. In Group 1, abortion was found in only one cow on 42 days postinfection (dpi; frequency of abortion = 12.5%), whilst all animals from Group 2 aborted on 35 dpi (frequency of abortion = 100%). Parasite DNA was detected by seminested PCR in maternal, foetal and placental tissues, confirming vertical transmission in Groups 1 and 2, although histological lesions had different frequencies and degrees of severity between the groups. There was evidence of lower pathogenicity of Nc-Bahia compared to Nc-1 when used in experimental infection, as it caused fewer abortions, as well as less frequent and milder histological lesions. This was the first time Nc-Bahia has been used for experimental infection.

Serologic evidence of Toxoplasma gondii infection in wild birds and mammals from southeast Brazil.

In this study, serum samples of 53 wild animals from two different states from the southeast region of Brazil were analyzed for the presence of anti-Toxoplasma gondii antibodies by the modified agglutination test (MAT), with a cut-off of 1: 5 for birds and of 1: 25 for mammals. Out of the sampled animals, 27 were birds and 26 were mammals, and from this total, 83% (n = 44) were free-living animals. Antibodies were found in 13 mammals, from which 11 were free-living animals, and in five birds, all of which were free-living. In this study, T. gondii antibodies were detected in four bird species (crested seriema, Cariama cristata; buff-necked ibis, Theristicus caudatus; picazuro pigeon, Patagioenas picazuro; and burrowing owl, Athene cunicularia) and in a giant anteater (Myrmecophaga tridactyla) for the first time.

Serologic survey of infectious diseases in populations of maned wolf (Chrysocyon brachyurus) and crab-eating fox (Cerdocyon thous) from Aguas Emendadas Ecological Station, Brazil.

Domestic dogs are reservoirs for many infectious diseases and may represent a potential source of infection for wild canid populations. A serologic investigation of antibodies to Toxoplasma gondii, Neospora caninum, Brucella abortus, and Leptospira spp. was conducted on three maned wolves (Chrysocyon brachyurus) and seven crab-eating foxes (Cerdocyon thous), all free-living, at the Aguas Emendadas Ecological Station (ESECAE), Federal District, Brazil, between February and October 2006. Out of the 10 samples analyzed, eight (80%) were seropositive for T. gondii: 3/3 (100%) of the maned wolves and 5/7 (71.4%) of the crab-eating foxes. None of the animals presented anti-N. caninum, B. abortus, and Leptospira spp. antibodies. This study demonstrated that the wild canid populations at ESECAE presented high exposure to T. gondii and indicated that there is high environmental contamination at the Station, which can be attributed to its proximity to urban zones, the presence of domestic cats in the study area, or the existence of other wild infected felines.

Anti-Toxoplasma gondii Antibodies in European Residents: A Systematic Review and Meta-Analysis of Studies Published between 2000 and 2020.

Toxoplasmosis has a major impact on animal and public health. Information regarding the seroprevalence of human Toxoplasma gondii infections from a European perspective has not yet been compiled to date. Thus, the present review summarized available resident data from the period 2000-2020. The overall seroprevalence of anti-T. gondii IgG was 32.1%, with great variability between countries (n = 30). The subgroup analysis identified different pooled prevalence data depending on the geographic area (p < 0.0001), target population (p = 0.0147), and serological diagnosis assays used (p = 0.0059). A high heterogeneity (I2 = 100%, p < 0.001; Q = 3.5e+05, d.f. = 135, p < 0.001) and degree of publication bias (Egger's test = 6.14, p < 0.001) were observed among the 134 studies considered. The occurrence of anti-T. gondii IgM, which was reported in 64.7% of studies, reached a pooled seroprevalence of 0.6%. In addition, among the eight main risk factors identified, "contact with soil", "consumption of undercooked beef", and "intake of unwashed vegetables" were the most significantly associated with infections. The fact that one-third of the European population has been exposed to T. gondii justifies extra efforts to harmonize surveillance systems and develop additional risk-factor analyses based on detailed source attribution assessment.