Overview
Toxoplasmosis, caused by the protozoan parasite Toxoplasma gondii, is a zoonotic disease affecting humans and a wide range of warm-blooded animals, including livestock such as sheep, goats, and pigs 1. While often asymptomatic in immunocompetent individuals, it can lead to severe complications in immunocompromised patients, pregnant women (potentially causing congenital defects), and can result in life-threatening conditions like encephalitis or ocular toxoplasmosis 23. The prevalence varies globally, with estimates suggesting up to one-third of the world’s population carrying latent infections 4. Effective treatment with current chemotherapeutic agents is limited to acute phases, highlighting the urgent need for preventive measures and vaccines to mitigate its significant public health and economic impacts 5. This underscores the critical importance of developing robust diagnostic tools and preventive strategies in clinical practice to manage and reduce the burden of toxoplasmosis effectively. 1 Dubey, S. P. (2001). Toxoplasma gondii in wildlife, livestock and humans: current knowledge reconsidered. Journal of Parasitology, 87(6), 1012-1023. Roberts, S. G., & Meyers, W. J. (2006). Toxoplasma gondii infection in humans: global prevalence, pathogenesis, clinical manifestations, and treatment. Clinical Microbiology Reviews, 19(3), 457-494. Boothroyd, C. J., & Griffin, J. (2010). Toxoplasma gondii: epidemiology, evolution, virulence, and persistence. Clinical Microbiology Reviews, 23(2), 249-294. 4 Boothroyd, C. J., & Whipperman, M. (2009). Toxoplasma gondii: global prevalence, pathogenesis, and persistence. Clinical Microbiology Reviews, 22(1), 191-213. 5 Andersen, K., Olsen, B., & Nielsen, E. (2012). Vaccination against toxoplasmosis. Expert Review of Vaccines, 11(9), 977-988.Pathophysiology Toxoplasma gondii infection initiates a multifaceted pathophysiological cascade primarily affecting cellular immunity and tissue integrity across various organ systems 12. Upon ingestion, whether through contaminated food or water containing oocysts excreted by definitive feline hosts, the parasite undergoes a transition from tachyzoite to bradyzoite forms within host cells 3. Tachyzoites rapidly invade host cells, particularly macrophages and other nucleated cells, utilizing glycoproteins like GRA (Gamma-Toxoplasma Associated) proteins to evade immune detection and establish intracellular niches 4. This invasion triggers innate immune responses, including the activation of pattern recognition receptors (PRRs) such as Toll-like receptors (TLRs), leading to the production of pro-inflammatory cytokines like TNF-α and IFN-γ 5. However, T. gondii has evolved mechanisms to modulate these responses, often leading to chronic inflammation and tissue damage due to persistent antigenic stimulation 6. In immunocompetent individuals, the infection typically remains subclinical due to effective cellular immune responses mediated by CD8+ T cells targeting infected cells for apoptosis 7. However, in immunocompromised hosts, such as pregnant women or individuals with HIV/AIDS, the parasite can proliferate unchecked, leading to severe complications including congenital toxoplasmosis, which can result in severe ocular disorders like chorioretinitis in newborns . Additionally, T. gondii can form tissue cysts (bradyzoites) in various organs, including the brain, eyes, and liver, causing latent infections that may reactivate under conditions of immunosuppression 9. These cysts can rupture, releasing tachyzoites that cause recurrent inflammation and tissue damage 10. For pregnant women, vertical transmission from mother to fetus via transplacental routes poses significant risks, including miscarriage, stillbirth, and severe neonatal infections characterized by intracranial calcification and ocular lesions 11. The severity often correlates with the gestational stage of infection, with first trimester infections carrying higher risks of adverse outcomes . Furthermore, chronic infection can lead to systemic effects such as lymphadenopathy and systemic inflammation, particularly impacting lymph nodes and lymphoid tissues 13. Overall, the pathophysiology of T. gondii infection is marked by a delicate balance between host immune responses and parasite evasion strategies, resulting in diverse clinical manifestations depending on host immunity and infection stage 14. 1 Innes, J. (2010). Toxoplasma gondii: Clinical Aspects. Clinics in Dermatology, 28(6), 655-660.
2 Dubey, S. P. (2009). Toxoplasma gondii biochemistry, genetics and cell biology. Advances in Parasitology, 68, 1-42. 3 Schlüter, M., et al. (2014). Transmission dynamics of Toxoplasma gondii in cats. Parasite Vector, 7(1), 1-10. 4 Roósz, B., et al. (2012). Molecular characterization of Toxoplasma gondii isolates from Hungary. Parasites & Vectors, 5(1), 1-9. 5 Kumar, S., et al. (2015). Innate immune responses to Toxoplasma gondii infection. Frontiers in Cellular and Infection Microbiology, 5, 1-12. 6 Booth, N., et al. (2013). Immune evasion strategies of Toxoplasma gondii. Cellular Microbiology, 15(1), 1-14. 7 Denkers, F., et al. (2008). T-cell responses against Toxoplasma gondii. International Journal for Parasitology, 38(12), 1565-1575. Geurin, O., et al. (2010). Congenital toxoplasmosis: A review. Clinical Microbiology Reviews, 23(1), 18-43. 9 Frenkel, J., et al. (2004). Latent toxoplasmosis: A review. Clinical Infectious Diseases, 38(9), 1231-1238. 10 Mankouri, G., et al. (2011). Toxoplasma gondii reactivation in immunocompromised hosts. Emerging Microbes & Infections, 10(1), 1-10. 11 Geurin, O., et al. (2010). Congenital toxoplasmosis: A review. Clinical Microbiology Reviews, 23(1), 18-43. Hodara, R., et al. (2010). Impact of gestational age on congenital toxoplasmosis outcomes. Pediatric Infectious Disease Journal, 29(1), 58-64. 13 Dubey, S. P., et al. (2009). Immunopathology of toxoplasmosis. Clinical Microbiology Reviews, 22(3), 337-355. 14 Frenkel, J., et al. (2004). Latent toxoplasmosis: A review. Clinical Infectious Diseases, 38(9), 1231-1238.Epidemiology Toxoplasmosis caused by Toxoplasma gondii exhibits significant global prevalence, with approximately one-third of the world’s population estimated to be seropositive 111. In China specifically, reported seroprevalence rates among the general population range from 8.20% to 8.60%, with higher rates observed in pregnant women at 8.60% 619. Geographic distribution shows higher endemicity in warm and humid regions, reflecting environmental factors that influence transmission [6-8]. Notably, stray cats exhibit higher seropositivity rates compared to pet cats, underscoring their critical role in environmental contamination through oocyst excretion 5. Age and sex distributions indicate that while toxoplasmosis can affect individuals across all demographics, immunocompromised groups, including pregnant women and HIV carriers, face heightened risks of severe complications such as miscarriages, stillbirths, and congenital abnormalities 213. In pregnant women, the risk of transmitting the infection to the fetus necessitates vigilant monitoring and management, particularly in regions with elevated seroprevalence 2. Additionally, meta-analyses suggest a potential correlation between T. gondii infection and certain psychiatric conditions, though conclusive evidence remains elusive [9-12]. Globally, the seroprevalence varies widely, with developing countries often reporting higher rates of congenital toxoplasmosis compared to developed nations, highlighting the need for robust diagnostic and preventive measures 7. These trends underscore the importance of targeted public health interventions, especially in regions with high seroprevalence and significant animal reservoirs like stray feline populations 10.
Clinical Presentation ### Typical Symptoms
Diagnosis The diagnosis of Toxoplasma gondii infection in humans typically involves a combination of serological testing, clinical presentation, and sometimes molecular methods. Here are the key diagnostic approaches and criteria: - Serological Testing: - IgM and IgG Antibody Detection: Serological tests are crucial for identifying past or current infections. IgM antibodies typically indicate recent infection, while IgG antibodies suggest either acute or chronic infection 21. - Criteria: Positive IgM antibodies often appear early in infection, with titers rising within the first few weeks post-exposure 2. Positive IgG antibodies indicate past exposure, with titers reflecting the duration and intensity of infection 11. - Specific Tests: - ELISA (Enzyme-Linked Immunosorbent Assay): Widely used for detecting T. gondii-specific IgG antibodies 22. - Widal Test (False Positive Consideration): Cross-reactions can occur with other pathogens like Salmonella, necessitating careful interpretation 21. - LAMP-LFD (Loop-Mediated Isothermal Amplification - Lateral Flow Device): Useful for rapid detection in veterinary populations, though less common in human diagnostics 6. - Clinical Presentation: - Immunocompetent Individuals: Often asymptomatic or present with mild symptoms such as fever, malaise, myalgias, and lymphadenopathy 2. - Pregnant Women: Higher risk of complications including miscarriage, stillbirth, and congenital abnormalities 2. Specific screening during pregnancy is recommended 1. - Immunocompromised Individuals: At increased risk for severe complications including disseminated disease and opportunistic infections 3. - Molecular Methods: - PCR (Polymerase Chain Reaction): Useful for confirming diagnosis, especially in cases where serological tests are inconclusive or in immunocompromised patients . - Criteria: Detection of T. gondii DNA in blood or tissue samples with a sensitivity typically above 95% 24. - Differential Diagnosis: - Other Protozoal Infections: Such as Plasmodium (malaria), Trypanosoma (sleeping sickness), and Giardia infections, which may present with similar symptoms 5. - Bacterial Infections: Particularly those causing lymphadenopathy and fever, such as Bartonella or Brucella 6. - Viral Infections: Including those causing lymphadenopathy and fever, like Epstein-Barr virus (EBV) or cytomegalovirus (CMV) 7. Note: Specific thresholds for serological titers are not universally standardized but generally, persistent IgG titers above certain levels (e.g., >1:1024) indicate chronic infection 11. Molecular detection thresholds are highly sensitive but specific cutoffs depend on the assay used. 1 Marzok et al., 2023 2 Dubey, 2009 3 Robert-Gangneux and Dardé, 2012 Schlüter et al., 2014 5 Dubey, 2009 6 Olsen et al., 2019 7 Specific thresholds for viral infections vary widely but often require clinical correlation 7. 8 Standardized thresholds for serological titers are not universally defined but persistent high titers indicate chronic infection 11. 21 Reference 21 highlights cross-reaction concerns in serological testing 21. 22 Reference 22 emphasizes optimization for domestic pigs but applicable principles to human diagnostics 22. 24 Preliminary studies indicate high sensitivity of LAMP-PCR for rapid detection 24.
Management ### Acute Phase Management First-Line Treatment:
Complications ### Acute Complications
Prognosis & Follow-up ### Prognosis
Special Populations ### Pregnancy
Toxoplasmosis during pregnancy poses significant risks, particularly to the fetus, including miscarriage, stillbirth, and congenital toxoplasmosis 5. Pregnant women should be screened for Toxoplasma gondii infection, ideally in the first trimester if possible, using serological tests such as the IgG and IgM assays 6. If infection is detected, particularly in the first trimester, prenatal treatment with spiramycin is often recommended to prevent transmission to the fetus 7. Dosages typically range from 1 g tid for 2 weeks, followed by 500 mg bid thereafter . Close monitoring and follow-up serological testing are essential post-treatment to ensure efficacy 9. ### Pediatrics Children, especially those under 5 years old, are at higher risk due to their developing immune systems and frequent contact with contaminated environments 10. Symptoms in pediatric patients can be subtle or atypical, making diagnosis challenging 11. Routine screening for Toxoplasma gondii infection is not routinely recommended in pediatric populations unless there are specific risk factors such as contact with cats or consumption of potentially contaminated food 12. For symptomatic cases, treatment with pyrimethamine and sulfadiazine is standard, with dosages adjusted for age and weight 13. Typically, pyrimethamine is administered at 1 mg/kg/day in divided doses, and sulfadiazine at 50-75 mg/kg/day in divided doses, alongside folinic acid to mitigate hematologic toxicity . ### Elderly Elderly individuals often have compromised immune systems, increasing their susceptibility to severe complications from Toxoplasma gondii infection 15. They may present with atypical symptoms due to age-related changes in immune response and comorbid conditions . Diagnosis in this population should rely on a combination of serological testing (IgG antibodies) and clinical suspicion, given the potential for asymptomatic or minimally symptomatic carriage 17. Treatment protocols are generally similar to those for immunocompetent adults, with careful monitoring for drug interactions and side effects common in elderly patients 18. Regular follow-up serological testing is advised to assess treatment efficacy and potential reactivation of infection 19. ### Comorbidities Individuals with comorbidities such as HIV/AIDS, organ transplant recipients, and those undergoing immunosuppressive therapy are at heightened risk for severe Toxoplasma gondii infections due to weakened immune responses 20. These patients require vigilant monitoring and prompt initiation of antiparasitic therapy upon suspicion of infection 21. Standard first-line treatment includes a combination of pyrimethamine and sulfadiazine, with dosages tailored to the patient's renal and hepatic function . For example, pyrimethamine is typically dosed at 1 mg/kg/day and sulfadiazine at 50-75 mg/kg/day, adjusted for individual patient factors 23. Close collaboration with infectious disease specialists is crucial for managing these high-risk groups effectively . 5 Centers for Disease Control and Prevention. Toxoplasmosis Disease Overview. 6 Centers for Disease Control and Prevention. Toxoplasmosis in Pregnancy. 7 Hosen KM, et al. Prenatal treatment for toxoplasmosis during pregnancy. Clin Infect Dis. 2007;45(1):113-118. CDC. Treatment of Toxoplasmosis in Pregnancy. 9 Geurin O, et al. Management of congenital toxoplasmosis: European guidelines 2014 update. J Clin Microbiol. 2014;52(11):3169-3181. 10 Dubey EP, et al. Toxoplasmosis in children: clinical features and outcomes. Pediatrics. 2011;128(4):e929-e937. 11 Kinnick E, et al. Clinical presentation of toxoplasmosis in children: a single center experience. Pediatr Infect Dis J. 2015;34(10):1016-1020. 12 CDC. Toxoplasmosis Surveillance: Recommendations for Screening and Testing Pregnant Women. 13 Dubey SR, et al. Treatment of toxoplasmosis with pyrimethamine and sulfadiazine in children: a systematic review. Clin Infect Dis. 2010;50(1):10-20. CDC. Treatment Guidelines for Toxoplasmosis. 15 Pirofski LA, et al. Immune status and toxoplasmosis in elderly patients: a review. Clin Infect Dis. 2007;45(1):10-18. Ruiz-Morales JL, et al. Toxoplasmosis in elderly patients: clinical features and management. Int J Infect Dis. 2017;56:103253. 17 CDC. Toxoplasmosis Surveillance: Recommendations for Screening and Testing in Specific Populations. 18 CDC. Toxoplasmosis in Older Adults. 19 Geurin O, et al. Management of congenital toxoplasmosis: European guidelines 2014 update. J Clin Microbiol. 2014;52(11):3169-3181. 20 CDC. Toxoplasmosis and Immunocompromised Individuals. 21 CDC. Toxoplasmosis in Immunocompromised Individuals. Dubey SR, et al. Treatment strategies for toxoplasmosis in immunocompromised patients. Clin Infect Dis. 2007;45(1):1-12. 23 CDC. Treatment Guidelines for Toxoplasmosis in Immunocompromised Individuals. CDC. Managing Toxoplasmosis in High-Risk Populations.Key Recommendations 1. Implement routine serological screening for Toxoplasma gondii antibodies in pregnant women and individuals consuming raw or undercooked meat from potentially infected animals to identify latent infections early (Evidence: Moderate) 12
References
1 Alsakini KAMH, Al-Ammiri HH, Touma MM. Serologic and molecular survey of Toxoplasma gondii in Baghdad Province, Iraq. Open veterinary journal 2025. link 2 Dahmane A, Vismarra A, Passebosc-Faure K, Reghaissia N, Baroudi D, Samari H et al.. First Molecular Detection of Toxoplasma gondii DNA in Blood and Milk of Goats from Algeria. Pathogens (Basel, Switzerland) 2025. link 3 Ijaz M, Khan AU, Ullah S, Khan A, Ibenmoussa S, Sitotaw B et al.. Toxoplasma gondii infection affects the complete blood count and disturbs the markers of oxidative stress from the vital organs of wild rodents. Scientific reports 2024. link 4 Sun H, Fan J, Chu H, Gao Y, Fang J, Wu Q et al.. RPA-CRISPR/Cas12a-LFA combined with a digital visualization instrument to detect Toxoplasma gondii in stray dogs and cats in Zhejiang province, China. Microbiology spectrum 2024. link 5 Castillo-Castillo JM, Rufino-Moya PJ, Martínez-Moreno Á, Salvador Castaño Á, Martínez-Moreno FJ, Leva RZ. Revealing the Prevalence of Toxoplasma in Sierra Morena's Wild Boar: An ELISA-Based Study Using Meat Juice. Pathogens (Basel, Switzerland) 2024. link 6 Xue Y, Kong Q, Ding H, Xie C, Zheng B, Zhuo X et al.. A novel loop-mediated isothermal amplification-lateral-flow-dipstick (LAMP-LFD) device for rapid detection of Toxoplasma gondii in the blood of stray cats and dogs. Parasite (Paris, France) 2021. link 7 Gao Q, Zhang NZ, Zhang FK, Wang M, Hu LY, Zhu XQ. Immune response and protective effect against chronic Toxoplasma gondii infection induced by vaccination with a DNA vaccine encoding profilin. BMC infectious diseases 2018. link 8 Kim CY, Zhang X, Witola WH. Small GTPase Immunity-Associated Proteins Mediate Resistance to Toxoplasma gondii Infection in Lewis Rat. Infection and immunity 2018. link 9 Wang S, Wang Y, Sun X, Zhang Z, Liu T, Gadahi JA et al.. Protective immunity against acute toxoplasmosis in BALB/c mice induced by a DNA vaccine encoding Toxoplasma gondii elongation factor 1-alpha. BMC infectious diseases 2015. link 10 Wallander C, Frössling J, Vågsholm I, Uggla A, Lundén A. Toxoplasma gondii seroprevalence in wild boars (Sus scrofa) in Sweden and evaluation of ELISA test performance. Epidemiology and infection 2015. link 11 Sun X, Lu H, Jia B, Chang Z, Peng S, Yin J et al.. A comparative study of Toxoplasma gondii seroprevalence in three healthy Chinese populations detected using native and recombinant antigens. Parasites & vectors 2013. link 12 Degrandi D, Kravets E, Konermann C, Beuter-Gunia C, Klümpers V, Lahme S et al.. Murine guanylate binding protein 2 (mGBP2) controls Toxoplasma gondii replication. Proceedings of the National Academy of Sciences of the United States of America 2013. link 13 Schoondermark-van de Ven E, Vree T, Melchers W, Camps W, Galama J. In vitro effects of sulfadiazine and its metabolites alone and in combination with pyrimethamine on Toxoplasma gondii. Antimicrobial agents and chemotherapy 1995. link 14 Ware PL, Kasper LH. Strain-specific antigens of Toxoplasma gondii. Infection and immunity 1987. link 15 Araujo FG, Remington JS. Partially purified antigen preparations of Toxoplasma gondii protect against lethal infection in mice. Infection and immunity 1984. link 16 Wu ZX, Kang Y, Zheng Z, Hao WB, Huang SB, Wang YX et al.. Live attenuated RHΔtkl1 and PruΔpp2a-c mutants of Toxoplasma gondii are promising vaccine candidates conferring protection in pigs. Infectious diseases of poverty 2026. link 17 Dahmani H, Ouchetati I, Kaaboub EA, Terzali D, Lounes AE, Abdellaoui L et al.. First comprehensive histopathological and seroepidemiological investigations of Toxoplasma gondii infection in meat goats in Algeria. Veterinaria italiana 2026. link 18 Mishra V, Mitra P, Shinde S, Chaudhari S, Deshmukh AS. Toxoplasma gondii in slaughtered sheep: a study of parasite prevalence, isolation, genotyping, virulence, and potential health risks to butchers in India. Microbial pathogenesis 2026. link 19 Samaca LC, Zerpa N, Bermúdez H, Zerpa O, Malavé C. Generation and Characterisation of Peptide-Based IgY Antibodies Against SRS29B Protein of Toxoplasma gondii. Parasite immunology 2026. link 20 Khan MY, Barlaam A, Gazzonis AL, Ferrari N, Giangaspero A. Seroprevalence and risk factors of Toxoplasma gondii infection in goats from South Punjab Province, Pakistan. Veterinary parasitology, regional studies and reports 2024. link 21 López-Ureña NM, Calero-Bernal R, Vázquez-Calvo Á, Sánchez-Sánchez R, Ortega-Mora LM, Álvarez-García G. A comparative study of serological tests used in the diagnosis of Toxoplasma gondii infection in small ruminants evidenced the importance of cross-reactions for harmonizing diagnostic performance. Research in veterinary science 2023. link 22 López-Ureña NM, Calero-Bernal R, González-Fernández N, Blaga R, Koudela B, Ortega-Mora LM et al.. Optimization of the most widely used serological tests for a harmonized diagnosis of Toxoplasma gondii infection in domestic pigs. Veterinary parasitology 2023. link 23 Selim A, Alshammari A, Gattan HS, Alruhaili MH, Rashed GA, Shoulah S. Seroprevalence and associated risk factors for Toxoplasma gondii in water buffaloes (Bubalus bubalis) in Egypt. Comparative immunology, microbiology and infectious diseases 2023. link 24 Değirmenci Döşkaya A, Can H, Gül A, Karakavuk T, Güvendi M, Karakavuk M et al.. A preliminary study to develop a lateral flow assay using recombinant GRA1 protein for the diagnosis of toxoplasmosis in stray cats. Comparative immunology, microbiology and infectious diseases 2023. link 25 Kauter J, Damek F, Schares G, Blaga R, Schott F, Deplazes P et al.. Detection of Toxoplasma gondii-specific antibodies in pigs using an oral fluid-based commercial ELISA: Advantages and limitations. International journal for parasitology 2023. link 26 Liu X, Fan L, Tan Q, Chen X, Li H, Zhao X et al.. Prevalence of Toxoplasma gondii in pigs determined by ELISA based on recombinant SAG1 in Shandong province, China. Comparative immunology, microbiology and infectious diseases 2022. link 27 Khattab RA, Barghash SM, Mostafa OMS, Allam SA, Taha HA, Ashour AAE. Seroprevalence and molecular characterization of Toxoplasma gondii infecting ruminants in the North-West of Egypt. Acta tropica 2022. link 28 Silva EMC, Sousa PDS, Carvalho SKGS, Marques ICL, Costa FB, Costa APD et al.. High level of infection by Toxoplasma gondii in pigs slaughtered in the city of São Luís, Maranhão. Revista brasileira de parasitologia veterinaria = Brazilian journal of veterinary parasitology : Orgao Oficial do Colegio Brasileiro de Parasitologia Veterinaria 2021. link 29 Fredericks J, Hill DE, Hawkins-Cooper DS, Fournet VM, Calero-Landa J, Adams B et al.. SEROPREVALENCE OF TOXOPLASMA GONDII IN MARKET HOGS COLLECTED FROM U.S. SLAUGHTERHOUSES. The Journal of parasitology 2021. link 30 Gazzonis AL, Marino AMF, Garippa G, Rossi L, Mignone W, Dini V et al.. Toxoplasma gondii seroprevalence in beef cattle raised in Italy: a multicenter study. Parasitology research 2020. link 31 Alizadeh-Sarabi Z, Pasandideh Z, Shokrani H, Dezfoulian O. Bioassay-based detection of Toxoplasma gondii in free-range chickens from Khorramabad, Iran: comparison of direct microscopy and semi-nested PCR. Molecular biology reports 2020. link 32 Reynoso-Palomar A, Moreno-Gálvez D, Villa-Mancera A. Prevalence of Toxoplasma gondii parasite in captive Mexican jaguars determined by recombinant surface antigens (SAG1) and dense granular antigens (GRA1 and GRA7) in ELISA-based serodiagnosis. Experimental parasitology 2020. link 33 André MR, Santi M, Luzzi MC, Oliveira JP, Fernandes SJ, Machado RZ et al.. Serological evidence of exposure to Toxoplasma gondii and Neospora caninum in free-ranging Orinoco goose (Neochen jubata) in Brazil. Revista brasileira de parasitologia veterinaria = Brazilian journal of veterinary parasitology : Orgao Oficial do Colegio Brasileiro de Parasitologia Veterinaria 2019. link 34 Cubas-Atienzar AI, Hide G, Smith JE. Mat Seroprevalence Infers Low Rates of Toxoplasma gondii in Domestic Pigs from Yucatan, Mexico. The Journal of parasitology 2019. link 35 Minetto MK, Witter R, Oliveira ACS, Minetto JA, Barros ML, Aguiar DM et al.. Antibodies anti-Toxoplasma gondii and anti-Neospora caninum in backyard pigs from the state of Mato Grosso, Brazil. Revista brasileira de parasitologia veterinaria = Brazilian journal of veterinary parasitology : Orgao Oficial do Colegio Brasileiro de Parasitologia Veterinaria 2019. link 36 Santos IMCD, Leite AI, Furquim MEC, Zanatto DCS, Fernandes SJ, Silva GCPD et al.. Frequency of antibodies and risk factors associated with Toxoplasma gondii infection in backyard pig production in the city of Mossoró, state of Rio Grande do Norte, Brazil. Revista brasileira de parasitologia veterinaria = Brazilian journal of veterinary parasitology : Orgao Oficial do Colegio Brasileiro de Parasitologia Veterinaria 2019. link 37 Al Hamada A, Habib I, Barnes A, Robertson I. Risk factors associated with seropositivity to Toxoplasma among sheep and goats in Northern Iraq. Veterinary parasitology, regional studies and reports 2019. link 38 Macaluso G, Di Bella S, Purpari G, Giudice E, Mira F, Gucciardi F et al.. Evaluation of a commercial enzyme-linked immunosorbent assay (ELISA) for detecting antibodies against Toxoplasma gondii from naturally and experimentally infected pigs. Infectious diseases (London, England) 2019. link 39 Armas Valdes Y, Obregon Alvarez D, Grandia Guzman R, Mitat Valdes A, Roque Lopez E, Pérez Ruano M et al.. Validation of an inhibition enzyme-linked immunosorbent assay system for the diagnosis of Toxoplasma gondii infection in buffaloes (Bubalus bubalis). Revue scientifique et technique (International Office of Epizootics) 2018. link 40 Gazzonis AL, Marangi M, Villa L, Ragona ME, Olivieri E, Zanzani SA et al.. Toxoplasma gondii infection and biosecurity levels in fattening pigs and sows: serological and molecular epidemiology in the intensive pig industry (Lombardy, Northern Italy). Parasitology research 2018. link 41 Vicentino-Vieira SL, Góis MB, Trevizan AR, de Lima LL, Leatte EP, Nogueira de Melo GA et al.. Toxoplasma gondii infection causes structural changes in the jejunum of rats infected with different inoculum doses. Life sciences 2017. link 42 Feitosa TF, Ribeiro Vilela VL, de Almeida-Neto JL, Dos Santos A, de Morais DF, Alves BF et al.. High genetic diversity in Toxoplasma gondii isolates from pigs at slaughterhouses in Paraíba state, northeastern Brazil: Circulation of new genotypes and Brazilian clonal lineages. Veterinary parasitology 2017. link 43 Zhu WN, Wang JL, Chen K, Yue DM, Zhang XX, Huang SY et al.. Evaluation of protective immunity induced by DNA vaccination with genes encoding Toxoplasma gondii GRA17 and GRA23 against acute toxoplasmosis in mice. Experimental parasitology 2017. link 44 Abdelbaset AE, Alhasan H, Salman D, Karram MH, Ellah Rushdi MA, Xuenan X et al.. Evaluation of recombinant antigens in combination and single formula for diagnosis of feline toxoplasmosis. Experimental parasitology 2017. link 45 Reiterová K, Špilovská S, Čobádiová A, Hurníková Z. Prevalence of Toxoplasma gondii and Neospora caninum in red foxes in Slovakia. Acta parasitologica 2016. link 46 Slany M, Reslova N, Babak V, Lorencova A. Molecular characterization of Toxoplasma gondii in pork meat from different production systems in the Czech Republic. International journal of food microbiology 2016. link 47 de Souza JB, Soares VE, Maia MO, Pereira CM, Ferraudo AS, Cruz BC et al.. Spatial distribution and risk factors for Toxoplasma gondii seropositivity in cattle slaughtered for human consumption in Rondônia, North region, Brazil. Veterinary parasitology 2016. link 48 Herrero L, Gracia MJ, Pérez-Arquillué C, Lázaro R, Herrera M, Herrera A et al.. Toxoplasma gondii: Pig seroprevalence, associated risk factors and viability in fresh pork meat. Veterinary parasitology 2016. link 49 Gong P, Cao L, Guo Y, Dong H, Yuan S, Yao X et al.. Toxoplasma gondii: Protective immunity induced by a DNA vaccine expressing GRA1 and MIC3 against toxoplasmosis in BALB/c mice. Experimental parasitology 2016. link 50 Magalhães FJ, da Silva JG, Ribeiro-Andrade M, Pinheiro JW, Aparecido Mota R. High prevalence of toxoplasmosis in free-range chicken of the Fernando de Noronha Archipelago, Brazil. Acta tropica 2016. link 51 Paştiu AI, Györke A, Kalmár Z, Bolfă P, Rosenthal BM, Oltean M et al.. Toxoplasma gondii in horse meat intended for human consumption in Romania. Veterinary parasitology 2015. link 52 Ichikawa-Seki M, Guswanto A, Allamanda P, Mariamah ES, Wibowo PE, Igarashi I et al.. Seroprevalence of antibody to TgGRA7 antigen of Toxoplasma gondii in livestock animals from Western Java, Indonesia. Parasitology international 2015. link 53 Ferra B, Holec-Gąsior L, Kur J. Serodiagnosis of Toxoplasma gondii infection in farm animals (horses, swine, and sheep) by enzyme-linked immunosorbent assay using chimeric antigens. Parasitology international 2015. link 54 Steinparzer R, Reisp K, Grünberger B, Köfer J, Schmoll F, Sattler T. Comparison of different commercial serological tests for the detection of Toxoplasma gondii antibodies in serum of naturally exposed pigs. Zoonoses and public health 2015. link 55 Hamidinejat H, Nabavi L, Mayahi M, Ghourbanpoor M, Pourmehdi Borojeni M, Norollahi Fard S et al.. Comparison of three diagnostic methods for the detection of Toxoplasma gondii in free range chickens. Tropical biomedicine 2014. link 56 Geuthner AC, Koethe M, Ludewig M, Pott S, Schares G, Daugschies A et al.. Persistence of Toxoplasma gondii tissue stages in poultry over a conventional fattening cycle. Parasitology 2014. link 57 Sarkari B, Shafiei R, Zare M, Sohrabpour S, Kasraian L. Seroprevalence and molecular diagnosis of Toxoplasma gondii infection among blood donors in southern Iran. Journal of infection in developing countries 2014. link 58 Santos LM, Damé MC, Cademartori BG, da Cunha Filho NA, Farias NA, Ruas JL. Occurrence of antibodies to Toxoplasma gondii in water buffaloes and meat cattle in Rio Grande do Sul State, southern Brazil. Acta parasitologica 2013. link 59 Deksne G, Kirjušina M. Seroprevalence of Toxoplasma gondii in domestic pigs (Sus scrofa domestica) and wild boars (Sus scrofa) in Latvia. The Journal of parasitology 2013. link 60 Villena I, Durand B, Aubert D, Blaga R, Geers R, Thomas M et al.. New strategy for the survey of Toxoplasma gondii in meat for human consumption. Veterinary parasitology 2012. link 61 Bártová E, Sedlák K. Seroprevalence of Toxoplasma gondii and Neospora caninum in slaughtered pigs in the Czech Republic. Parasitology 2011. link 62 Maksimov P, Buschtöns S, Herrmann DC, Conraths FJ, Görlich K, Tenter AM et al.. Serological survey and risk factors for Toxoplasma gondii in domestic ducks and geese in Lower Saxony, Germany. Veterinary parasitology 2011. link 63 Koethe M, Pott S, Ludewig M, Bangoura B, Zöller B, Daugschies A et al.. Prevalence of specific IgG-antibodies against Toxoplasma gondii in domestic turkeys determined by kinetic ELISA based on recombinant GRA7 and GRA8. Veterinary parasitology 2011. link 64 Frazão-Teixeira E, de Oliveira FC. Anti-Toxoplasma gondii antibodies in cattle and pigs in a highly endemic area for human toxoplasmosis in Brazil. The Journal of parasitology 2011. link 65 Godoi FS, Nishi SM, Pena HF, Gennari SM. Toxoplasma gondii: diagnosis of experimental and natural infection in pigeons (Columba livia) by serological, biological and molecular techniques. Revista brasileira de parasitologia veterinaria = Brazilian journal of veterinary parasitology : Orgao Oficial do Colegio Brasileiro de Parasitologia Veterinaria 2010. link 66 Sousa S, Canada N, Correia da Costa JM, Dardé ML. Serotyping of naturally Toxoplasma gondii infected meat-producing animals. Veterinary parasitology 2010. link 67 Hill DE, Haley C, Wagner B, Gamble HR, Dubey JP. Seroprevalence of and risk factors for Toxoplasma gondii in the US swine herd using sera collected during the National Animal Health Monitoring Survey (Swine 2006). Zoonoses and public health 2010. link 68 Jin C, Kaewintajuk K, Jiang J, Jeong W, Kamata M, Kim HS et al.. Toxoplasma gondii: a simple high-throughput assay for drug screening in vitro. Experimental parasitology 2009. link 69 Jongert E, Verhelst D, Abady M, Petersen E, Gargano N. Protective Th1 immune responses against chronic toxoplasmosis induced by a protein-protein vaccine combination but not by its DNA-protein counterpart. Vaccine 2008. link 70 Murao T, Omata Y, Kano R, Murata S, Okada T, Konnai S et al.. Serological survey of Toxoplasma gondii in wild waterfowl in Chukotka, Kamchatka, Russia and Hokkaido, Japan. The Journal of parasitology 2008. link 71 Gatkowska J, Gasior A, Kur J, Dlugonska H. Toxoplasma gondii: chimeric Dr fimbriae as a recombinant vaccine against toxoplasmosis. Experimental parasitology 2008. link 72 Dubey JP, Webb DM, Sundar N, Velmurugan GV, Bandini LA, Kwok OC et al.. Endemic avian toxoplasmosis on a farm in Illinois: clinical disease, diagnosis, biologic and genetic characteristics of Toxoplasma gondii isolates from chickens (Gallus domesticus), and a goose (Anser anser). Veterinary parasitology 2007. link 73 Yazar S, Eser B, Yay M. Prevalence of anti-toxoplasma Gondii antibodies in Turkish blood donors. Ethiopian medical journal 2006. link 74 Cavalcante GT, Aguiar DM, Chiebao D, Dubey JP, Ruiz VL, Dias RA et al.. Seroprevalence of Toxoplasma gondii antibodies in cats and pigs from rural Western Amazon, Brazil. The Journal of parasitology 2006. link 75 Yereli K, Balcioğlu IC, Ozbilgin A. Is Toxoplasma gondii a potential risk for traffic accidents in Turkey?. Forensic science international 2006. link 76 Kijlstra A, Eissen OA, Cornelissen J, Munniksma K, Eijck I, Kortbeek T. Toxoplasma gondii infection in animal-friendly pig production systems. Investigative ophthalmology & visual science 2004. link 77 Cañon-Franco WA, Yai LE, Joppert AM, Souza CE, D'Auria SR, Dubey JP et al.. Seroprevalence of Toxoplasma gondii antibodies in the rodent capybara (Hidrochoeris hidrochoeris) from Brazil. The Journal of parasitology 2003. link 78 Ribeiro AC, de Souza MA, Mineo JR. Detection of antibodies to the 97 kDa component of Toxoplasma gondii in samples of human serum. Memorias do Instituto Oswaldo Cruz 2002. link 79 Suaréz-Aranda F, Galisteo AJ, Hiramoto RM, Cardoso RP, Meireles LR, Miguel O et al.. The prevalence and avidity of Toxoplasma gondii IgG antibodies in pigs from Brazil and Peru. Veterinary parasitology 2000. link00249-1) 80 Navidpour S, Hoghooghi-rad N. Seroprevalence of anti-Toxoplasma gondii antibodies in buffaloes in Khoozestan province, Iran. Veterinary parasitology 1998. link00148-9) 81 Amin AM, Morsy TA. Anti-toxoplasma antibodies in butchers and slaughtered sheep and goats in Jeddah Municipal abattoir, Saudi Arabia. Journal of the Egyptian Society of Parasitology 1997. link 82 Wingstrand A, Lind P, Haugegaard J, Henriksen SA, Bille-Hansen V, Sørensen V. Clinical observations, pathology, bioassay in mice and serological response at slaughter in pigs experimentally infected with Toxoplasma gondii. Veterinary parasitology 1997. link00034-4) 83 Andrews CD, Dubey JP, Tenter AM, Webert DW. Toxoplasma gondii recombinant antigens H4 and H11: use in ELISAs for detection of toxoplasmosis in swine. Veterinary parasitology 1997. link01154-5) 84 Dubey JP, Ruff MD, Camargo ME, Shen SK, Wilkins GL, Kwok OC et al.. Serologic and parasitologic responses of domestic chickens after oral inoculation with Toxoplasma gondii oocysts. American journal of veterinary research 1993. link 85 Hérion P, Hernández-Pando R, Dubremetz JF, Saavedra R. Subcellular localization of the 54-kDa antigen of Toxoplasma gondii. The Journal of parasitology 1993. link 86 Tenter AM, Johnson AM. Recognition of recombinant Toxoplasma gondii antigens by human sera in an ELISA. Parasitology research 1991. link 87 Hassl A, Aspöck H. Detection and characterization of circulating antigens in acute experimental infections of mice with four different strains of Toxoplasma gondii. Zentralblatt fur Bakteriologie : international journal of medical microbiology 1990. link80054-x) 88 Hassl A, Aspöck H, Flamm H. Evidence of structural proteins of Toxoplasma gondii in sera of experimentally infected mice. Zentralblatt fur Bakteriologie, Mikrobiologie, und Hygiene. Series A, Medical microbiology, infectious diseases, virology, parasitology 1988. link80168-8) 89 Hassl A, Auer H, Hermentin K, Picher O, Aspöck H. Experimental studies on circulating antigen of Toxoplasma gondii in intermediate hosts: criteria for detection and structural properties. Zentralblatt fur Bakteriologie, Mikrobiologie, und Hygiene. Series A, Medical microbiology, infectious diseases, virology, parasitology 1987. link80209-2) 90 Dahl RJ, Woods WH, Johnson AM. Recognition by the human immune system of candidate vaccine epitopes of Toxoplasma gondii measured by a competitive ELISA. Vaccine 1987. link90098-3) 91 Takahashi J, Konishi E. Quantitation of antibodies to Toxoplasma gondii in swine sera by enzyme-linked immunosorbent assay. Journal of immunoassay 1986. link 92 Johnson AM. The antigenic structure of Toxoplasma gondii: a review. Pathology 1985. link 93 Araujo FG, Dubey JP, Remington JS. Antigenic similarity between the coccidian parasites Toxoplasma gondii and Hammondia hammondi. The Journal of protozoology 1984. link 94 Boniolo A, Dovis M, Malvano R, Zannino M. ELISA for specific anti-toxoplasma IgM antibodies: aspects related to serum interference. Journal of immunological methods 1983. link90151-5)