ToxoDB Genotype Research Articles

Diagnosis of Swine Toxoplasmosis by PCR and Genotyping of Toxoplasma gondii from pigs in Henan, Central China

BackgroundToxoplasma gondii, a widely prevalent protozoan parasite, causes serious toxoplasmosis infections in humans and other animals. Among livestock, pigs are susceptible to T. gondii infection. Despite Henan being one of the biggest pig-raising provinces in China, little information exists on the epidemiology of toxoplasmosis in this location. Therefore, we molecularly characterized DNA samples from pigs in Henan. A total of 1647 samples, including 952 from dead piglets, 478 from seriously sick fattening pigs and 217 from abortion sows, were collected from different animal hospitals or pig farms from 10 different cities in Henan (2006–2008). Each pig corresponded to a separate pig farm. DNA was extracted from 3 to 5 g of the most severely affected pig tissue (liver, spleen, lung, hilar lymph nodes and amniotic fluid) after postmortem examination. The presence of the T. gondii B1 gene was detected using nested polymerase chain reactions (PCR). Genotyping was performed directly on DNA from the PCR-positive tissue samples using 11 PCR restriction fragment length polymorphism markers (SAG1, 5′- and 3′-SAG2, alternative SAG2, SAG3, BTUB, GRA6, L358, PK1, c22–8, c29–2, and Apico).ResultsOf all samples, thirty-four were positive for the T. gondii B1 gene (2.06%, 95% CI: 1.86%–2.26%) from four cities, including 31 from NanYang city, one (PgXY 1) from Xinyang City, one (PgZZ 1) from Zhengzhou City and one (PgZK1) from Zhoukou City. The prevalence was found to be highest in piglets than in fattening pigs and sows. And the difference was statistically significant (P<0.01). The following 32 samples were genotyped with complete data: 13 hilar lymph node tissue samples, seven liver tissue samples, seven lung tissue samples, four spleen tissue samples, and one amniotic fluid sample. Only one genotype, belonging to ToxoDB Genotype #9, was identified.ConclusionsThis is the first large-scale survey molecularly characterizing T. gondii from pigs in Henan. The results of the present study revealed that T. gondii infection is present in swine in Henan and is a potential source of foodborne toxoplasmosis in the investigated areas. Implementation of effective control measures for T. gondii to reduce the chance of zoonotic toxoplasmosis spreading from pig farms may be warranted. The results show that the ToxoDB #9 genotype may be the dominant T. gondii lineage in mainland China. These findings strengthen the limited Chinese T. gondii epidemiology database.

Molecular detection and genetic characterization of Toxoplasma gondii in farmed raccoon dogs (Nyctereutes procyonoides) in Shandong province, eastern China

Toxoplasma gondii is a successful opportunistic parasite, affecting a wide range of vertebrate animals and humans. Genetic diversity of T. gondii in raccoon dogs (Nyctereutes procyonoides) is of great importance to understand the transmission of T. gondii in the environment. However, no information is available about the distribution of genetic diversity of T. gondii infection in raccoon dogs. This study was conducted to estimate the prevalence and genetic characterization of T. gondii from raccoon dogs in Shandong province, eastern China. A total of 314 brain tissue samples of raccoon dogs were collected and genomic DNA was extracted and assayed for T. gondii infection using semi-nested PCR targeting B1 gene. The positive DNA samples were typed at 10 genetic markers (SAG1, SAG2(5′+3′ SAG2, alter.SAG2), SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico) by multiplex multilocus nested polymerase chain reaction-restriction fragment length polymorphism (Mn- PCR-RFLP) technology. Thirty-five (11.15%) of 314 DNA samples were detected positive. Only six samples were completely typed at all genetic loci, and these samples represented ToxoDB genotype#9. Two sample were typed at 9 genetic loci and one was typed at 8 genetic loci, all of them represented Type I. To our knowledge, this is the first report of genetic characterization of T. gondii in raccoon dogs in China. These results revealed the existence of genetic diversity of T. gondii in raccoon dogs in China. These data provided base-line information for controlling T. gondii infection in raccoon dogs.

Predominance of atypical genotypes of Toxoplasma gondii in free-roaming chickens in St. Kitts, West Indies

BackgroundToxoplasma 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.MethodsHearts 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).ResultsOverall, 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.ConclusionsThe 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.

Seroprevalence, isolation and co-infection of multiple Toxoplasma gondii strains in individual bobcats (Lynx rufus) from Mississippi, USA

Toxoplasma gondii causes lifelong chronic infection in both feline definitive hosts and intermediate hosts. Multiple exposures to the parasite are likely to occur in nature due to high environmental contamination. Here, we present data of high seroprevalence and multiple T. gondii strain co-infections in individual bobcats (Lynx rufus). Unfrozen samples (blood, heart, tongue and faeces) were collected from 35 free ranging wild bobcats from Mississippi, USA. Toxoplasma gondii antibodies were detected in serum by the modified agglutination test (1:≥200) in all 35 bobcats. Hearts from all bobcats were bioassayed in mice and viable T. gondii was isolated from 21; these strains were further propagated in cell culture. Additionally, DNA was extracted from digests of tongues and hearts of all 35 bobcats; T. gondii DNA was detected in tissues of all 35 bobcats. Genetic characterisation of DNA from cell culture-derived isolates was performed by multiplex PCR using 10 PCR-RFLP markers. Results showed that ToxoDB genotype #5 predominated (in 18 isolates) with a few other types (#24 in two isolates, and #2 in one isolate). PCR-DNA sequencing at two polymorphic markers, GRA6 and GRA7, detected multiple recombinant strains co-infecting the tissues of bobcats; most possessing Type II alleles at GRA7 versus Type X (HG-12) alleles at GRA6. Our results suggest that individual bobcats have been exposed to more than one parasite strain during their life time.

First isolation and RFLP genotyping of Toxoplasma gondii from crab-eating fox (Cerdocyon thous—Linnaeus, 1766)

Wild animals may play an important role in the transmission and maintenance of Toxoplasma gondii in the environment. The purpose of the present study was to isolate and genotype T. gondii from a free-ranging crab-eating fox (Cerdocyon thous—Linnaeus, 1766). A crab-eating fox in critical health condition was attended in a veterinary hospital in Recife, Pernambuco State, Brazil. The animal died despite emergency treatment. The brain was collected aseptically and destined for mouse bioassay. One isolate of T. gondii was obtained, and Polymerase Chain Reaction − Restriction Fragment Length Polymorphism (PCR-RFLP) was used to assess genetic variability at 11 markers (SAG1, SAG2, altSAG2, SAG3, BTUB, GRA6, c228, c292, L358, PK1 and APICO). A murine model was used to assess the virulence of the isolate. Using the PCR-RFLP, genotype ToxoDB #13 was identified, which is considered an atypical strain. The isolate was classified as avirulent in the murine model. This is the first study to report T. gondii infection in the crab-eating fox.

First genetic characterization of Toxoplasma gondii infection in common quails (Coturnix coturnix) intended for human consumption in China

Toxoplasma gondii is widely distributed in humans and other animals including birds throughout the world. However, little is known of the molecular epidemiology and genotypes of T. gondii infecting quails in China. Therefore, the present study was conducted to characterize T. gondii genotypes in common quails in China. During December 2014 to October 2015, a total of 390 muscle tissue samples of common quails were collected and the T. gondii B1 gene was amplified using a nested PCR, and the positive samples were genotyped at 11 genetic markers (SAG1, 5′-and 3′-SAG2, alternative SAG2, SAG3, BTUB, GRA6, L358, PK1, c22-8, c29-2, and Apico) using multilocus polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technology. Twenty-five of the 390 common quails (6.41%) were tested positive by nested PCR. Three DNA samples from the 25 positive samples were typed completely and were identified as ToxoDB Genotype #9 (http://toxodb.org/toxo/). The results of the present study indicated that T. gondii infection in common quails was common in China, which provided the information of T. gondii genetic diversity in this host species. This is the first genetic characterization of T. gondii isolates from quails in China, which is useful for monitoring and controlling the T. gondii infection in quails, other animals and humans.

Seroprevalence and genetic characterization of Toxoplasma gondii in masked palm civet (Paguma larvata) in Hainan province, tropical China

In the present study, the seroprevalence, risk factors and genotyping of Toxoplasma gondii in masked palm civet were investigated in tropical China. A total of 500 serum were collected from five administrative farms in tropical China, and assayed for T. gondii antibodies by modified agglutination test (MAT). The brain samples of 20 aborted fetuses were examined by semi-nested-PCR, and positive aborted fetuses (50%) were necropsied to collect the brain tissue for molecular and bioassay examinations. Genomic DNA was extracted from the 29 brain tissues of infected mice and T. gondii B1 gene was amplified using multilocus PCR-RFLP. Overall, 27.6% (95% CI: 23.682–31.518) of the animals was positive for T. gondii antibodies. Ages of masked palm civet was considered as a main risk factor associated with T. gondii infection. 4 DNA samples (13.8%) were positive for the T. gondii B1 gene. Three samples belong to ToxoDB#9, and one belongs to genotype the type II variant (ToxoDB genotype#3). Our results indicated that ToxoDB Genotype#9 has a distribution in masked palm civet that could be potential reservoirs for T. gondii transmission, which may pose a threat to human health.

Comparison of genotypes of Toxoplasma gondii in domestic cats from Australia with latent infection or clinical toxoplasmosis

Whether Toxoplasma gondii genotype is associated with disease severity in naturally occurring toxoplasmosis in domestic cats is unknown. The aim of this study was to compare genotypes of T. gondii in latently infected cats with those in cats with clinical toxoplasmosis. Results of a PCR targeting the B1 gene to detect T. gondii DNA were positive in tissue samples from 11 of 17 (65%) seropositive cats tested including four with clinical toxoplasmosis and seven with latent infections, as determined by serology, histologic findings and immunohistochemistry. Three of the four cats with clinical toxoplasmosis were immunosuppressed. Complete genotyping was performed in seven cats using PCR-RFLP at 12 loci (SAG1, 5′SAG2 and 3′SAG2, altSAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico) and direct sequencing of the multi-copy B1 gene. Partial genotyping using six loci was performed in one cat with latent infection. T. gondii type II (ToxoDB genotype #3) was determined in four cats with clinical toxoplasmosis and three cats with latent toxoplasmosis Novel T. gondii B1 gene polymorphisms were detected in two strains (at nucleotide posititions 233, 366 and 595) and a B1 gene polymorphism unique to Australia was identified in another (guanine/adenine at nucleotide position 378). One cat was co-infected with two or more type-II like strains at 3′SAG2. The results of this study suggest that the infecting T. gondii genotype, based on these 12 loci, is not a determinant of clinical disease in cats naturally infected with T. gondii and type II strains are prevalent in Australia.

Seroprevalence and genotypes of Toxoplasma gondii isolated from pigs intended for human consumption in Liaoning province, northeastern China.

BackgroundGenetic information for Toxoplasma gondii isolates from pigs in eastern, south, and southwestern regions of China has been reported previously. However, there are no data from pigs in the northeastern area of the country. To better understand the epidemiology of T. gondii, we determined the seroprevalence and genotypes of T. gondii from pigs slaughtered for human consumption in Liaoning province, northeastern China.FindingsOut of 2063 pigs examined, 233 (11.26 %) were seropositive for T. gondii by the modified agglutination test (MAT), and viable parasites were isolated by bioassay in mice from 23 (9.87 %) of the 233 seropositive pigs. Fifteen out of 23 isolates were genotyped using 10 PCR-restriction fragment length polymorphism (RFLP) genetic markers including SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico. One isolate was identified as ToxoDB genotype #3 (type II-variant), and one was genotype #1 or #3. The other 13 isolates were ToxoDB #9 (type Chinese 1).ConclusionsTo our knowledge, this is the first report of T. gondii isolation and genotyping from pigs in northeastern China. This study indicates that pigs are a potential source for transmission of T. gondii to humans, therefore poses a potential public health concern. The genotyping results revealed the presence of genotype Chinese 1 in northeastern China, enriching the scope of T. gondii genotypes distribution in eastern Asia.

Proteomic Profiling of Mouse Liver following Acute Toxoplasma gondii Infection.

Toxoplasma gondii remains a global public health problem. However, its pathophysiology is still not-completely understood particularly the impact of infection on host liver metabolism. We performed iTRAQ-based proteomic analysis to evaluate early liver protein responses in BALB/c mice following infection with T. gondii PYS strain (genotype ToxoDB#9) infection. Our data revealed modification of protein expression in key metabolic pathways, as indicated by the upregulation of immune response and downregulation of mitochondrial respiratory chain, and the metabolism of fatty acids, lipids and xenobiotics. T. gondii seems to hijack host PPAR signaling pathway to downregulate the metabolism of fatty acids, lipids and energy in the liver. The metabolism of over 400 substances was affected by the downregulation of genes involved in xenobiotic metabolism. The top 10 transcription factors used by upregulated genes were Stat2, Stat1, Irf2, Irf1, Sp2, Egr1, Stat3, Klf4, Elf1 and Gabpa, while the top 10 transcription factors of downregulated genes were Hnf4A, Ewsr1, Fli1, Hnf4g, Nr2f1, Pparg, Rxra, Hnf1A, Foxa1 and Foxo1. These findings indicate global reprogramming of the metabolism of the mouse liver after acute T. gondii infection. Functional characterization of the altered proteins may enhance understanding of the host responses to T. gondii infection and lead to the identification of new therapeutic targets.

Molecular detection and genetic characterization of Toxoplasma gondii infection in sika deer (Cervus nippon) in China

The objective of the present study was to investigate the prevalence and genetic characterization of Toxoplasma gondii infection in sika deer in China. During August 2014 to November 2014, a total of 450 tissue samples coming from 150 sika deer were collected to detect the T. gondii B1 gene using a nested PCR, and the positive samples were genotyped at 11 genetic markers (SAG1, 5′- and 3′-SAG2, alternative SAG2, SAG3, BTUB, GRA6, L358, PK1, c22-8, c29-2, and Apico) using multilocus polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technology. Seventeen of 150 sika deer (11.33%) were tested positive by nested PCR. Six DNA samples from the 17 positive samples were completely typed, in which 4 samples from lung tissues, and 2 from muscular tissues, were identified as ToxoDB Genotype #9 (http://toxodb.org/toxo/). The results of the present study revealed the existence of T. gondii infection in sika deer in China, which provided the information of T. gondii genetic diversity in this host species. This study also indicated that ToxoDB Genotype #9 has a wide distribution in sika deer that could be potential reservoirs for T. gondii transmission, which may pose a threat to human health.

Seroprevalence, risk factors and genetic characterization of Toxoplasma gondii in free-range white yaks (Bos grunniens) in China

The objective of this study was to determine the seroprevalence, risk factors and genotypes of Toxoplasma gondii in white yaks (Bos grunniens) in China. A total of 974 serum samples were collected from white yaks in Tianzhu Tibetan Autonomous County (TTAC), Gansu province, northwest China for detecting T. gondii antibodies by the modified agglutination test (MAT), and 414 tissues belonging to 138 white yaks were collected for detecting T. gondii DNA by amplification of B1 gene with a semi-nested PCR. A total of 155 serum samples (15.91%) were seropositive for T. gondii antibodies at a 1:100 cut-off, and 10 DNA samples (7.25%) were positive for the T. gondii B1 gene, which were genetically characterized using multilocus PCR-RFLP. Only one genotype (ToxoDB#9) was identified from two samples with complete genotyping results. Statistically significant differences were not observed between T. gondii seroprevalence and gender, season or pregnancy in the logistic regression analysis (P>0.05). Ages of white yaks was considered as a main risk factor associated with T. gondii infection. Our results indicated a widespread exposure to T. gondii among white yaks, and revealed the genotype ToxoDB#9 of T. gondii in white yaks for the first time in China.

First isolation of Toxoplasma gondii from cats of Colima, Mexico: Tissue distribution and genetic characterization

Toxoplasma gondii is among the commonest zoonotic infectious agents worldwide. It infects many warm-blooded animals, including felines, the definitive hosts. This parasite is now classified in 15 haplogroups spread out around the world. Few reports reveal a predominance of genotypes I and III in Mexico, although recombinant and atypical variants have also been found in humans and animals. The aim of this study was to detect, isolate and genotype T. gondii from cats of Colima Mexico, and to analyze tissue distribution of the parasite. IgG specific antibodies were investigated in 48 serum samples from unwanted and stray cats by indirect ELISA. Isolation in mice and molecular characterization by PCR-RFLP and sequencing were attempted using pools of brain, heart, liver, lung, spleen and brachiocephalic muscle samples of seropositive cats. Fourteen animals (29.2%) were seropositive, the frequency ranged between 27.3 and 40% among the different localities. Ten seropositive animals were euthanized, eight of them were positive for the B1 gene by conventional PCR. More frequently infected tissues were the brachiocephalic muscle (75.0%) the brain (63.0%) and the spleen (63.0%). Genotype III was determined for the SAG3 locus of the parasite infecting an unwanted cat. Tachyzoites were isolated from the peritoneal cavity of two mice inoculated with the tissue pool of one kitten. Type I alleles were found in SAG1, SAG2, SAG3, BTUB, GRA6, c29-2 and PK1 loci, while c22-8 was type II, and L358 and Apico were type III. This genotype corresponds to ToxoDB genotype #28. This is the first T. gondii isolate genetically characterized in Colima, Mexico and is different to other isolations of the country.

Genetic characterization of Toxoplasma gondii in Yunnan black goats (Capra hircus) in southwest China by PCR-RFLP.

BackgroundToxoplasma gondii is a protozoan parasite that infects almost all warm-blooded animals and human beings. Goats are one of the susceptible animals to T. gondii. However, little is known of genetic diversity of T. gondii in Yunnan black goats in China. The objective of this present study was to determine the genotypes of T. gondii isolates from black goats in Yunnan province, southwest China.MethodsGenomic DNA was extracted from liver (n = 403), lung (n = 403) and lymph nodes (n = 250) of Yunnan black goats and assayed for T. gondii infection by semi-nested PCR of B1 gene. Then, the positive DNA samples were typed at 10 genetic markers using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technology. These markers include 9 nuclear loci, namely, SAG1, SAG2 (5’-SAG2 and 3’-SAG2, alternative SAG2), SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and an apicoplast locus Apico.ResultsOut of 403 tested samples, 20 (4.96%) DNA samples were T. gondii positive by amplification of B1 gene. Among them, 2 isolates were genotyped at all loci, and 6 isolates were genotyped for 8 or more loci. In total, seven samples belong to ToxoDB PCR-RFLP genotype#10 (Type I), and one belongs to genotype ToxoDB #9.ConclusionsTo our knowledge, this is the first report of ToxoDB#9 and ToxoDB#10 T. gondii in Yunnan black goats in China. These results revealed a wide distribution of these T. gondii in Yunnan black goats in China, which has important implications for public health.

Genetic characterization of Toxoplasma gondii isolates from eared doves (Zenaida auriculata) in Brazil.

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.

Prevalence and genetic characterization of Toxoplasma gondii infection in bats in southern China

Toxoplasma gondii can infect a wide variety of warm-blooded animals, including bats. Limited information on T. gondii infection in bats is available in China. The objective of the present study was to determine prevalence and genetic diversity of T. gondii infection in bats in southern China. A total of 608 bats representing 12 species, including 120 Aselliscus stoliczkanus, 59 Myotis chinensis, 11 Miniopterus schreibersii, 53 Rhinolophus affinis, 32 Rhinolophus pusillus, 81 Hipposideros armiger, 28 Hipposideros fulvus, 32 Cynopterus brachyotis, 14 Cynopterus sphinx, 45 Eonycteris spelaea, 109 Hipposideros larvatus, and 24 Taphozous melanopogon, were collected from Yunnan and Guangxi provinces, southern China. They were examined for the presence of T. gondii DNA by amplification of the B1 gene using a nested PCR, and the positive samples were genotyped at 11 genetic loci (SAG1, 5′- and 3′-SAG2, alternative SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico) using multilocus polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technology. Fifty-nine (9.7%) of these bats were detected positive by PCR but only five of these positive DNA samples were completely typed at all loci; of which 4 samples, 2 from A. stoliczkanus, and 2 from H. larvatus, belonged to ToxoDB Genotype #10, and the other one from H. larvatus was identified as ToxoDB Genotype #9 (http://toxodb.org/toxo/). To our knowledge, this is the first report of molecular detection and genetic characterization of T. gondii infection in bats in China. The results show that these bats are potential reservoirs for T. gondii transmission, which may pose a threat to human health.

Seroprevalence and genetic characterization of Toxoplasma gondii in three species of pet birds in China

BackgroundToxoplasmosis, caused by the protozoan parasite Toxoplasma gondii, is one of the most common zoonosis worldwide, affecting a wide range of warm-blooded mammals and birds worldwide. However, no information on T. gondii infection in pet birds in China is available. Therefore, this study was performed to determine the prevalence of T. gondii infection in pet birds in Gansu province, China.MethodsA total of 687 blood samples were collected from pet birds (Carduelis spinus, Alauda gulgula, Cocothraustes migratorlus) in three representative administrative regions in Gansu province, northwest China between August 2011 and September 2012 T. gondii antibodies were determined using the modified agglutination test (MAT). Genomic DNA was extracted from the brain tissues of seropositive pet birds and T. gondii B1 gene was amplified using a semi-nested PCR.DNA samples giving positive B1 amplification were then genetically characterized using multi-locus PCR-RFLP.ResultsThe overall T. gondii seroprevalence was 11.21% (77/687). C. spinus had the highest T. gondii seroprevalence (11.65%), followed by A. arvensis (11.39%) and C. migratorlus (5.26%), these differences were not statistically significant (P > 0.05). Of 77 DNA samples, 8 were positive for the T. gondii B1 gene, four showed complete genotyping results. Only one genotype (the Type II variant: ToxoDB genotype #3) was identified.ConclusionsThe results of the present survey indicated the presence of T. gondii infection in pet birds in Gansu province, China. These data provide base-line information for the execution of control strategies against T. gondii infection in pet birds. To our knowledge, this is the first report documenting the occurrence of T. gondii prevalence and genotype in pet birds in China.

First Report of Genotyping ofToxoplasma gondiiin Free-LivingMicrotus fortisin Northeastern China

Toxoplasma gondii is an intracellular protozoan parasite which imperils the health of almost all warm-blooded animals, including humans. The objective of this study was to determine genetic characterization of T. gondii in free-living Microtus fortis (reed vole) in Jilin province, northeastern China. A total of 104 DNA samples, 74 from Gongzhuling and 30 from Baicheng, were extracted from lung tissues of M. fortis , and 56 (53.8%) of them were positive for T. gondii by semi-nested polymerase chain reaction of the B1 gene. These positive DNA samples were typed at 10 genetic markers including SAG1, 5'- and 3'-SAG2, alternative SAG2, BUTB, GRA6, L358, PK1, c22-8, c29-2, and Apico. Four samples were successfully genotyped at all genetic loci and grouped to 2 distinct genotypes; 2 samples belonged to ToxoDB Genotype no. 10 (Type I) and the other 2 presented ToxoDB Genotype no. 9 ( http://toxodb.org/toxo/ ); 4 samples were genotyped at 8 genetic loci, in which 2 samples belonged to ToxoDB Genotype no. 10 and 2 presented ToxoDB Genotype no. 9. To our knowledge, this is the first report of genetic typing of T. gondii from free-living M. fortis in northeast China. The results suggest that the Type I and ToxoDB Genotype no. 9 could be a potential risk factor for transmission through the reed vole in this region.

Toxoplasma gondii genotypes isolated from pregnant women with follow-up of infected children in southern Brazil

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. 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. Three children displayed normal cognitive/psychomotor development, and one child displayed Sabin's tetrad (TgCTBral). Vertical transmission of the two genotypes was observed and contributes to knowledge of T. gondii strains isolated from humans in Brazil.

Epidemiology of toxoplasmosis in white tailed deer (Odocoileus virginianus): Occurrence, congenital transmission, correlates of infection, isolation, and genetic characterization of Toxoplasma gondii

The prevalence of Toxoplasma gondii in white tailed deer (WTD) in the USA is high but little is known of the epidemiology of toxoplasmosis in this host. In the present study, we compared T. gondii seroprevalence from 749 WTD collected in 2012 and 2013 from a Metropolitan Park in Ohio and 487 WTD deer shot in Minnesota during 2008, 2009, and 2010. Serum samples were tested for antibodies to T. gondii by the modified agglutination test (cut-off titer, 25). Additionally myocardial samples from 123 seropositive WTD from Ohio were digested in pepsin and the digests were bioassayed for the isolation of T. gondii. Furthermore, to estimate transplacental rate of transmission, brains from 155 fetuses (included twins) from 148 deer from Minnesota were bioassayed in mice for the isolation of viable T. gondii. Seroprevalence of T. gondii varied with the year of collection, geography, and the age of deer. Of the Ohio deer sampled in 2012 and 2013 seroprevalences for the two years were similar (73.4% and 75.7%, respectively); remarkably 150 (66.1%) of 227 deer of <1 year of age were seropositive. Of the Minnesota deer, seroprevalence was lowest for the year 2008 (14.8%, 26/175) versus 2009 (27.7%, 59/213), and 2010 (25.2%, 25/99), thought to be related to environmental temperatures. Viable T. gondii was isolated in mice from the myocardium of four WTD from Ohio, and brain of one WTD fetus from Minnesota. Tachyzoites from infected mouse tissues were further propagated in cell culture. The DNA isolated from culture-derived tachyzoites of these five T. gondii isolates was characterized using 11 PCR-RFLP markers (SAG1, 5′- and 3′-SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico). Four genotypes were found, including ToxoDB genotype no. 1 (Type II), no. 2 (Type III), no. 3 (Type II variant) and no. 146. Results indicate fluctuating seroprevalence, probably related to weather and warrant further epidemiological studies.