Toxoplasma Infection Research Articles

Seroprevalence of Toxoplasma, Rubella, and Cytomegalovirus Infections in Women of Childbearing Age Admitted to Kafkas University Health Research and Application Hospital: A Three-Year Evaluation

TORCH enfeksiyonları, Toxoplasma gondii, Rubella, Sitomegalovirus (CMV), Herpes simpleks virüs ve diğer bazı patojenlerin neden olduğu, anne-fetal bariyeri geçebilen ve potansiyel olarak fetüsün gelişimini olumsuz etkileyebilen bir grup enfeksiyonu ifade etmektedir. Bu çalışmada, doğurganlık çağındaki kadınlarda konjenital enfeksiyonlara neden olma potansiyeline sahip Toksoplazma, Rubella ve CMV’ye karşı oluşan antikorların seroprevalansının belirlenmesi amaçlanmıştır. 1 Ocak 2020 ve 1 Aralık 2022 tarihleri arasında laboratuvarımıza anti-Toksoplazma IgM ve IgG, anti-Rubella IgM ve IgG, anti-CMV IgM ve IgG serolojisinin araştırılması amacı ile gönderilen doğurganlık çağındaki 15–49 yaş arası toplam 2155 kadına ait test sonuçları retrospektif olarak incelenmiştir. Hasta serumlarında, IgM ve IgG antikorları Enzyme Linked Fluorescent Assay (ELFA-VIDAS, bioMérieux, Fransa) yöntemi ile tespit edilmiştir. Çalışmamızda anti-Toksoplazma IgM pozitifliği %0,5, anti-Toksoplazma IgG pozitifliği %19,4; anti-Rubella IgM pozitifliği %0,5, anti-Rubella IgG pozitifliği %92,3; anti-CMV IgM pozitifliği %0,5, anti-CMV IgG pozitifliği ise %99,9 olarak tespit edilmiştir. Toksoplazma IgG seropozitifliği ile yaş grubu arasında istatistiksel olarak anlamlı bir farklılık olduğu ve yaşın azalması ile istatistiksel olarak arttığı tespit edilmiştir (p

The infectious status of patients with optic neuritis of inflammatory and demyelinating etiologies

Purpose: to study the prevalence of various chronic infections, the frequency of their reactivation and characteristic associations of microorganisms in patients with optic neuritis of various etiologies.Material and methods. 13 patients with optic neuritis (ON) and 12 patients with ON and multiple sclerosis were tested for a broad range of infectious agents in their blood serum.Results. All patients were shown to have mixed infections; 64 % of them had an association of 4 or more infectious agents. The patients of both groups were infected with Epstein-Barr virus (100 %), Cytomegalovirus (92 %) and Herpex simplex viruses (92 %) types 1 and/or 2 with serological signs of their reactivation. The combination of Herpes virus reactivation, Toxoplasma and urogenital infection was more often detected in patients with demyelinating ON. In patients with multiple sclerosis, a mutual correlation was detected: the higher the degree of infection (combination of 5 or more pathogens), the lower the visual acuity at the onset of the disease (p < 0.05) and the less favourable the vision prognosis.Conclusion. Possibly, mixed infection may play an important role in the pathogenesis of ON, including that of demyelinating etiology, as a trigger or an aggravating factor.

The Association of Toxoplasma gondii with the Combination of Cardiovascular Disease, Chronic Kidney Disease, or Chronic Liver Disease: A Preliminary Study.

Toxoplasma gondii is a protozoan parasite widespread worldwide, with over 40 million individuals in the United States. It may infect vital organs such as the heart, kidneys, and liver, resulting in chronic infections. The main objective of this study is to investigate the association of Toxoplasma infection with the combination of cardiovascular disease, chronic kidney disease (CKD), or chronic liver disease (CLD). The National Health and Nutrition Examination Survey (NHANES 2009-2010) data were used, and the association of infection with chronic disease was assessed with biomarkers and indexes using statistical modeling. The percentage of participants with a combination of CLD and CKD was higher among Toxoplasma positive participants compared to the negative participants (2.76 vs. 1.26). Furthermore, exposure to T. gondii may increase the odds of cardiovascular disease, CKD, or CLD, or vice versa.

CD4+ T Cell Responses to Toxoplasma gondii Are a Double-Edged Sword.

CD4+ T cells have been found to play critical roles in the control of both acute and chronic Toxoplasma infection. Previous studies identified a protective role for the Toxoplasma CD4+ T cell-eliciting peptide AS15 (AVEIHRPVPGTAPPS) in C57BL/6J mice. Herein, we found that immunizing mice with AS15 combined with GLA-SE, a TLR-4 agonist in emulsion adjuvant, can be either helpful in protecting male and female mice at early stages against Type I and Type II Toxoplasma parasites or harmful (lethal with intestinal, hepatic, and spleen pathology associated with a storm of IL6). Introducing the universal CD4+ T cell epitope PADRE abrogates the harmful phenotype of AS15. Our findings demonstrate quantitative and qualitative features of an effective Toxoplasma-specific CD4+ T cell response that should be considered in testing next-generation vaccines against toxoplasmosis. Our results also are cautionary that individual vaccine constituents can cause severe harm depending on the company they keep.

Seroprevalence, Risk Factors and Maternal-Fetal Outcomes of Toxoplasma gondii in Pregnant Women from WHO Eastern Mediterranean Region: Systematic Review and Meta-Analysis.

The protozoan parasite Toxoplasma gondii may cause serious illness in the immunocompromised. The Toxoplasma gondii seropositive prevalence in pregnant women in WHO Eastern Mediterranean Region countries is inconsistent in the literature and it is associated with outcomes that have not be fully elucidated, hence the need for a better understanding of the pooled seroprevalence and associated maternal and fetal outcomes. The objective was to conduct a systematic literature review and determine the pooled prevalence of WHO Eastern Mediterranean Regional countries' pregnant women's seroprevalence of Toxoplasma gondii and the maternal-fetal outcomes. This quantitative study examined WHO Eastern Mediterranean countries' maternal-fetal outcomes and Toxoplasma gondii prevalence in pregnant women. The targeted population was pregnant women, while the primary outcome was seropositivity of Toxoplasma gondii, while other outcomes such as maternal and fetal associations and risk factors were determined PubMed, SCOPUS, MEDLINE, and Index Medicus for the Eastern Mediterranean Region (IMEMR) databases were searched up until 30 January 2023. The search terms used were "Toxoplasma gondii" OR "Toxoplasma infection" AND "Pregnant woman" or pregnan* OR Antenatal OR Prenatal OR Gravidity OR Parturition OR Maternal AND WHO Eastern Mediterranean Region). OpenMeta-Analyst and Jamovi were used to analyze the generated data. In total, 95 of 2947 articles meeting the inclusion criteria examined Toxoplasma gondii prevalence in pregnant women from WHO Eastern Mediterranean countries. The pooled prevalence of Toxoplasma gondii in pregnant women was 36.5% (95%CI: 32.6-40.4) with a median value of 35.64%, range values of 1.38-75.30%, with 99.61% heterogeneity. The pooled seroprevalence of IgG of Toxoplasma gondii was 33.5% (95%CI: 29.8-37.2) with a median value of 33.51%, and a range values of 1.38-69.92%; the pooled seroprevalence of IgM was 3.6% (95%CI: 3.1-4.1)) with a median value of 3.62 and range values of 0.20-17.47%, while cases of pooled seroprevalence of both IgG and IgM positivity was 3.0% (95%CI: 1.9-4.4) with a median value of 2.05 and a range values of 0.05-16.62%. Of the Toxoplasma gondii seropositive women, 1281/3389 (34.8%) 174/1765 (32.9%), 1311/3101 (43.7%), and 715/1683 (40.8%) of them had contact with cats, drank unprocessed milk, ate raw or undercooked meat and ate unwashed raw vegetables, respectively. The maternal-fetal outcomes associated with Toxoplasma gondii seropositivity were a history of abortions, miscarriage, stillbirth, intrauterine fetal death, and premature birth, which were found in 868/2990 (32.5%), 112/300 (36.1%), 111/375 (25.7%), 3/157 (1.9%) and 96/362 (20.1%) of women who tested positive for Toxoplasma gondii antibodies. The study found a high proportion of Toxoplasma gondii seroprevalence in pregnant women in the WHO Eastern Mediterranean Region, which may be linked to poor outcomes for mothers and their babies. Thus, pregnant women require monitoring and comprehensive prevention strategies for Toxoplasma gondii infection.

Seroprevalence of Toxoplasma infection in individuals occupationally exposed to livestock and raw meat: A case-control study.

The expectancy of Toxoplasma gondii transmitted from livestock and raw meat to humans is a public health problem and is an example of the One Health theory. This survey aimed to determine the seroprevalence and risk factors related to this common infection in individuals occupationally exposed (IOE) to livestock, raw meat and viscera in industrial slaughterhouses and livestock fields in Isfahan province, central Iran. This study is a case-control survey carried out on the 401 serum samples of IOE (including slaughterhouse workers, butchers, veterinarians, veterinary technicians, livestock farmers and farm workers) compared to 401 archived samples of the general population (that all matched with cases by region, age and gender). All 802 samples were investigated for anti-T. gondii IgM and anti-T. gondii IgG using enzyme-linked immunosorbent assay. A statistically significant higher anti-T. gondii IgG occurrence (p<0.001) was observed in IOE compared to the control group (46.1% vs. 31.4%). According to our knowledge, this is the first case-control study on the seroprevalence of anti-T. gondii in IOE to livestock in central Iran. These findings show a potentially significant association between T. gondii seropositivity and occupational exposure to livestock. Therefore, it is essential to develop guidelines for preventing disease transmission among IOE to livestock, raw meat and viscera in industrial slaughterhouses and livestock fields.

Toxoplasmosis Screening during Pregnancy in a Romanian Infectious Diseases Tertiary Center: Results of a 15 Years Follow-Up Program.

Maternal infection with Toxoplasma gondii during pregnancy may have serious consequences for the fetus. In Romania, screening for toxoplasmosis is included in the first antenatal visit. A retrospective study was performed on all toxoplasmosis antenatal screening patients between May 2008 and February 2023. Twenty-seven thousand one hundred sixty-nine (27,169) pregnant women presented for prenatal screening once (22,858) or several times: during the same pregnancy (209) or during multiple pregnancies (4102). Thirty-one thousand six hundred fifty-eight (31,658) tests for IgM and IgG antibodies were performed. Nine thousand eighty-three (9083) tests (28.69%), corresponding to 7911 women (29.12%), were positive for IgG antibodies. The seroprevalence increased with patients' age, decreased in time intervals, and was more frequently associated with rural residence. At risk for acquiring the infection during the pregnancy were women with negative anti-Toxoplasma IgG antibodies (70.88%), but only 0.9% of them presented for rescreening during the same pregnancy. Acute Toxoplasma infection (ATI) was suspected in 44 patients (0.16%) due to IgG seroconversion and/or low or borderline IgG avidity. A questionnaire follow-up interview was performed, and no congenital toxoplasmosis was identified in children born from mothers with probable ATI. Our study demonstrates poor compliance with the screening program in the Romanian population.

Synthesis, X-ray Structure, Hirshfeld, DFT Conformational, Cytotoxic, and Anti-Toxoplasma Studies of New Indole-Hydrazone Derivatives.

The hydrazones 3a-c, were synthesized from the reaction of indole-3-carbaldehyde and nicotinic acid hydrazide, isonicotinic acid hydrazide, and benzoic acid hydrazide, respectively. Their structures were confirmed using FTIR, 1HNMR, and 13CNMR spectroscopic techniques. Exclusively, hydrazones 3b and 3c were confirmed using single crystal X-ray crystallography to exist in the Eanti form. With the aid of DFT calculations, the most stable configuration of the hydrazones 3a-c in gas phase and in nonpolar solvents (CCl4 and cyclohexane) is the ESyn form. Interestingly, the DFT calculations indicated the extrastability of the EAnti in polar aprotic (DMSO) and polar protic (ethanol) solvents. Hirshfeld topology analysis revealed the importance of the N…H, O…H, H…C, and π…π intermolecular interactions in the molecular packing of the studied systems. Distribution of the atomic charges for the hydrazones 3a-c was presented. The hydrazones 3a-c showed a polar character where 3b has the highest polarity of 5.7234 Debye compared to the 3a (4.0533 Debye) and 3c (5.3099 Debye). Regarding the anti-toxoplasma activity, all the detected results verified that 3c had a powerful activity against chronic toxoplasma infection. Compound 3c showed a considerable significant reduction percent of cyst burden in brain homogenates of toxoplasma infected mice representing 49%.

Group 1 metabotropic glutamate receptor expression defines a T cell memory population during chronic Toxoplasma infection that enhances IFN-gamma and perforin production in the CNS

Within the brain, a pro-inflammatory response is essential to prevent clinical disease due to Toxoplasma gondii reactivation. Infection in the immunocompromised leads to lethal Toxoplasmic encephalitis while in the immunocompetent, there is persistent low-grade inflammation which is devoid of clinical symptoms. This signifies that there is a well-balanced and regulated inflammatory response to T. gondii in the brain. T cells are the dominant immune cells that prevent clinical disease, and this is mediated through the secretion of effector molecules such as perforins and IFN-γ. The presence of cognate antigen, the expression of survival cytokines, and the alteration of the epigenetic landscape drive the development of memory T cells. However, specific extrinsic signals that promote the formation and maintenance of memory T cells within tissue are poorly understood. During chronic infection, there is an increase in extracellular glutamate that, due to its function as an excitatory neurotransmitter, is normally tightly controlled in the CNS. Here we demonstrate that CD8+ T cells from the T. gondii-infected brain parenchyma are enriched for metabotropic glutamate receptors (mGluR’s). Characterization studies determined that mGluR+ expression by CD8+ T cells defines a distinct memory population at the transcriptional and protein level. Finally, using receptor antagonists and agonists we demonstrate mGluR signaling is required for optimal CD8+ T cell production of the effector cytokine IFNγ. This work suggests that glutamate is an important environmental signal of inflammation that promotes T cell function. Understanding glutamate’s influence on T cells in the brain can provide insights into the mechanisms that govern protective immunity against CNS-infiltrating pathogens and neuroinflammation.

The potent synergistic effect of Brassica oleracea against congenital Toxoplasma infection in rat model

Congenital toxoplasmosis is among the leading causes of fetus damage and abortion. Pyrimethamine + sulfadiazine is usually the chosen treatment against toxoplasmosis during pregnancy. Severe cutaneous adverse responses, teratogenicity, and changes in bilirubin metabolism are just a few examples of the pyrimethamine + sulfadiazine's toxicity. The present study aimed to assess the potent effect of a Brassica oleracea-based diet to synergistically enhance the effect of pyrimethamine + sulfadiazine in combating congenital toxoplasmosis and reduce the drug adverse effects. Broccoli (Brassica oleracea) was included in a standard pellet diet for the T. gondii infected pregnant rats. At the end of the experiment interleukins (IL-6, IL- 10), TNF-α, NF-κB and IFN-γ levels, biochemical analyses, parasite count and histopathological studies were assessed. A noticeable decrement was observed in the combination treated rat group (pyrimethamine + sulfadiazine and broccoli-based diet feed). Moreover, the biochemical analysis further validated the potent combined therapy effectiveness. The parasitological study revealed that the mean tachyzoites count was the lowest among pregnant rats and the offspring group after receiving the formulated combined treatment. Moreover, the histopathological studies revealed that the combined treatment had a significant synergistic effect on the tissues of spleen and liver. While the cerebral cortex of fetuses maternally fed on the broccoli-based diet showed mild symptoms of damage with normal neurons. Taken together, the broccoli-based diet enhanced the immunological, biochemical, and histological responses against toxoplasmosis and also decreased the vertical transmission of congenital toxoplasmosis.

Serological and molecular detection of Toxoplasma gondii in ß. thalassemia patients.

Toxoplasma gondii is a worldwide opportunistic protozoan causing life-threatening infection in immunocompromised patients, while frequently asymptomatic in immunocompetent individuals. The current study aimed to detect T. gondii; serologically and molecularly in ß. thalassemia patients and evaluate the association of infection with some hematological parameters in these patients. Blood samples were collected from 100 ß. thalassemia patients. Serological diagnosis of T. gondii using ELISA for IgG and IgM antibodies was performed. Molecular diagnosis by Real-Time (RE) PCR was performed using specifically designed primers amplifying 389bp fragments of Toxoplasma genome. 45 patients (45%) had anti-Toxoplasma IgG antibodies with no detectable IgM antibodies while both anti-Toxoplasma IgM and IgG antibodies were noticed in 10 patients (10%). IgM only antibodies were discovered in two cases (2%). The total seropositivity rate among patients was 57%. RE PCR analysis revealed Toxoplasma DNA in 20% out of 100 patients. PCR and serological examination showed slight agreement. A statistically significant relation was observed between the results of IgG and IgM ELISA and PCR for the detection of T. gondii infection among patients with ß. thalassemia. None of the studied risk factors (age, gender, contact with cats, consumption of undercooked meat) or hematological parameters (ESR, anemia degree, ferritin level, type of blood transfusion, spleen status) showed statistically significant association with Toxoplasma infection. It can be concluded that patients with thalassemia have a high risk of infection with T. gondii. RE PCR should be used as a diagnostic method in association with serology especially in immunocompromised patients to increase sensitivity.

Current status of TORCH infection Seroprevalence in pregnant women: a cross-sectional study in Al Sharqia Governorate, Egypt

BackgroundTORCH infections during pregnancy significantly impact neonatal and maternal mortality rates worldwide. This study aimed to gather baseline serological data for pregnant women's immunological status to infection and determine if definite TORCH pathogens (cytomegalovirus, rubella virus, and Herpes simplex virus) were associated with Toxoplasma infection, to improve prenatal care and provide appropriate infection control strategies.MethodologyBlood samples were gathered from 210 pregnant women attending Al Zagazig University hospitals from February to May 2023. Samples were examined for specific IgM and IgG antibodies against TORCH pathogens by electrochemiluminescence technique.ResultsRegarding TORCH infection, 60 (28.6%) cases were seronegative, while 77 (36.7%), 63 (30.0%), 56 (26.7%), and 15 (7.1%) were positive IgG antibodies against Toxoplasma gondii, cytomegalovirus, rubella virus, and Herpes simplex virus, respectively. There was no estimate for IgM for cytomegalovirus, rubella virus, or Herpes simplex virus, indicating that no primary infection had been detected during the pregnancy. There was a statistically significant association between seroprevalence of toxoplasmosis infections (IgM and IgG) and age group ≤ 25 years, which is the most common childbearing age group. Cytomegalovirus seropositivity was found in those beyond 25 years (P-value 0.001). Antibodies to mono-infections were found in 97/210 (46.2%) subjects. It is substantially higher under-25 years age group, 71/97 (73.2%), P-value of 0.001. 45/210 (21.4%) participants had antibodies to two agents, with no significant difference in the age group over 25 years, 26/45 (57.8%). Antibodies to three agents were assessed in eight instances, all under 25 years.ConclusionsAccording to our findings, serological evaluation for the TORCH complex in all pregnant women is recommended to determine infection immunity, current immunization regimens, and infection reactivation. Low TORCH antibodies rates amongst pregnant women in Egypt's Sharqia governorate might be an appropriate starting point for prenatal screening initiatives.

The Medical Relevance of Toxoplasma Infections in Terms of the Safety of Blood Recipients under Immunosuppression-A Meta-Analysis.

Laboratory diagnosis of Toxoplasma gondii infection plays a crucial role in ensuring the safety of blood recipients, especially in the case of immunosuppressed people, such as organ transplant patients. Toxoplasmosis, caused by the parasite Toxoplasma gondii, is a potential threat to people with weakened immune systems, and blood transfusions from infected donors can lead to severe complications. In this publication, we analyze the medical relevance of Toxoplasma infection in the context of the safety of blood recipients, focusing on the immunosuppressed patient population. We present various diagnostic methods, such as serological, molecular, and microscopic tests, which can detect the presence of Toxoplasma gondii in donors' blood. We also discuss the importance of adequately interpreting diagnostic results, considering risk factors, and detectability of the infection. We pay special attention to high-sensitivity and -specificity diagnostic techniques, which allow us to minimize the risk of Toxoplasma gondii transmission to blood recipients. Our findings have important implications for clinical practice and organ transplantation guidelines, emphasizing the need to diagnose and monitor Toxoplasma infections in blood donors and recipients.

Nanoemulsion of Spiramycin against Tachyzoites of Toxoplasma gondii, RH Strain: Preparation, Toxicology, and Efficacy Studies.

Toxoplasma infection is caused by Toxoplasma gondii, which is an intracellular protozoan parasite. This infection consequently lead various congenital disabilities during pregnancy in patients. Spiramycin (Spi), a macrolide antibiotic, is typically recommended for T. gondii infection in pregnant women. We aimed to prepare the nanoemulsion of spiramycin (NE-Spi) and to evaluate the activity of this formulation in tachyzoites of T. gondii, RH strain. This study was conducted in 2019-2021 at the School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. NE-Spi was prepared by spontaneous emulsification. The effects of this nanoemulsion on the viability of cultured cells were measured using MTT assay. To estimate the effects of NE-Spi on tachyzoites of T. gondii, RH strain, different concentrations of NE-Spi, S-Spi (suspension of spiramycin), and NE (nanoemulsion without any spiramycin) were added to tachyzoites and then stored for 30, 60, 90, 120 min and 24 h in 250 µg/ml concentration at room temperature. Finally, Tachyzoites mortality rates were evaluated by trypan blue staining. Of note, flow cytometry was conducted to confirm the obtained results. The final particle size of NE-Spi was calculated to be 11.3 nm by DLS and TEM. Thereafter, using MTT assay, in 62.5 µg/ml concentration of NE-Spi, the Vero cells viability was obtained as 82%. The highest mortality rates of tachyzoites of T.gondii, RH strain were observed at 250 µg/ml concentration and after 120 min of exposure, but it was not significantly different from 24 h of exposure. NE-Spi has lethal efficacy on T. gondii RH strain in-vitro.

Toxoplasma infection and Rhesus blood group system: A systematic review and meta-analysis.

Toxoplasmosis is one of the most common infections in humans and animals, which is caused by an obligate intracellular opportunistic parasite known as Toxoplasma gondii (T. gondii). Some data have shown that both Rhesus (Rh)-positive and Rh-negative individuals differ in response to biological factors, including Toxoplasma infection. Therefore, this systematic review and meta-analysis was conducted to investigate the scientific evidence regarding the possible association between the Rh blood group and Toxoplasma infection and to determine the seroprevalence of T. gondii in the Rh blood group system. The research was conducted on PubMed, ScienceDirect, ProQuest, and Google Scholar databases until January 2023. Twenty-one cross-sectional studies were included with a total of 10910 people. The data were synthesized using a random effect model with 95% confidence intervals (CIs). The overall prevalence of T. gondii was calculated at 32.34% (CI 95%: 28.23-36.45%) and 33.35% (CI 95%: 19.73-46.96%) in Rh-positive and Rh-negative blood groups. In addition, the pooled OR for the relationship between the Rh blood group and the seroprevalence of T. gondii was 0.96 (95% CI: 0.72-1.28). This meta-analysis showed a high prevalence of Toxoplasma infection in both Rh-negative and positive blood groups. This systematic review and meta-analysis revealed that no significant association was found between toxoplasmosis and Rh factor. Because of the limited number of studies in this field, more research is recommended to determine the exact relationship between toxoplasmosis and the Rh factor.

A genetic method specifically delineates Th1-type Treg cells and their roles in tumor immunity

Regulatory T (Treg) cells expressing the transcription factor (TF) Foxp3 also express other TFs shared by T helper (Th) subsets under certain conditions. Here, to determine the roles of T-bet-expressing Treg cells, we generate a mouse strain, called VeDTR, in which T-bet/Foxp3 double-positive cells are engineered to be specifically labeled and depleted by a combination of Cre- and Flp-recombinase-dependent gene expression control. Characterization of T-bet+Foxp3+ cells using VeDTR mice reveals high resistance under oxidative stress, which is involved in accumulation of T-bet+Foxp3+ cells in tumor tissues. Moreover, short-term depletion of T-bet+Foxp3+ cells leads to anti-tumor immunity but not autoimmunity, whereas that of whole Treg cells does both. Although ablation of T-bet+Foxp3+ cells during Toxoplasma infection slightly enhances Th1 immune responses, it does not affect the course of the infection. Collectively, the intersectional genetic method reveals the specific roles of T-bet+Foxp3+ cells in suppressing tumor immunity.

Seroprevalence and Molecular detection of Toxoplasma gondii Infections in Rodents and Cats in Mbeya District, Tanzania.

Toxoplasmosis is a zoonotic disease that is increasingly becoming an important but neglected disease of global concern. Cats and other feline species are the definitive host while rodents are the reservoirs of Toxoplasma gondii the causative agent of the disease. The study aimed to establish both Toxoplasma infection and exposure status in rodents and cats in Mbeya District, Tanzania. A cross-sectional study was employed where a total of 300 rodents and 52 cats were obtained from purposively selected wards in Mbeya district. To establish the infection statutes the serum and brain tissue in rodents and cats were collected for laboratory analysis. Indirect ELISA (ID.vet Innovative Diagnostics-France) was employed to determine T. gondiiinfection status in sera where seropositive samples and some of cat seronegative sample were subjected to conventional PCR analysis targeting GRA 6 gene for confirmation of the infection. Serological assay detected exposure status in 8.7 % (95% CI=0.057-0.124) of the rodent’s serum samples and none in cats. PCR assay confirmed the infection in five of the rodent seropositive samples and one seronegative cat sample. Most of the seropositive samples belonged to Rattus rattus the most abundant (57%) rodent species captured in households and storage facilities. No significant variations in seroprevalence were found between locations, sex, species, or habitats. It is concluded that the study established the exposure status and actual infection of T.gondii in rodents in the study area and that R. rattus were the most exposed and infected. This highlights the risk of transmission of the infection to humans given the possible interaction with rodents in houses and stores where they were commonly trapped. The community health education on aspects of disease transmission, clinical signs and disease management is recommended. Furthermore, a regular animal and human screening for the disease to reveal its epidemiological patterns is also recommended.

Evaluation of the protective immune response of an attenuated strain of Toxoplasma gondii with long-term passages on the Gecko cell line

Toxoplasma gondii is an obligate intracellular parasite that causes the zoonoses disease, named toxoplasmosis, with global prevalence. Until now, no cost-effective treatment method has been found to deal with toxoplasma, and vaccination is the best way to deal with the infection. In the case of pathogenic protozoa, mainly live vaccines have had successful results compared to other vaccine platforms. This study evaluated the efficacy of a live experimental vaccine through long-term passages on the Gecko cell line (Z1) in inducing a protective immune response in BALB/c mice. Thirty mice were divided into three equal groups; G1: the immunized/challenged group (injection of attenuated strain), G2: the immunized/unchallenged group (injection of attenuated strain), and G3: the control group (injection of culture medium).One month after immunization, the studied mice were challenged with 1ₓ103 live tachyzoites of Toxoplasma acute RH strain. We performed Serological investigations, including evaluating antibodies, interferon-gamma (IFN-γ), and interleukins 2, 4, 10, and 12 (IL-2,4,10,12). At the study's end, a molecular test was performed on brain and liver tissues in the immunized groups to check the presence of parasites. The results from the serological tests for the evaluation of antibodies, interferon-gamma (IFN-γ), and interleukins 10 and 12 (IL-10, 12) show a significant difference (p < 0.05) between the vaccinated group and the control group, which are essential indicators of protective immunity against toxoplasma infection. Thus, in the vaccinated group, the survival rate of mice against the challenge was 70%. Also, in group two (G2), the attenuated strain of Toxoplasma gondii had no pathogenicity, and all mice survived until the end of the study period. Molecular results also showed the absence of parasites in the brain and liver tissues in this immunized group and the parasite was found in only one case of liver tissue in G1. Therefore, the attenuated strain has caused significant and protective humoral and cellular immune responses in vaccinated groups. This study showed that with the long-term passage of the acute strain on the Gecko cell line, it is possible to quickly obtain a non-diseased attenuated strain with the ability to induce protective immunity. This successful finding can introduce further research to achieve a promising vaccine in the target animals.

Detection of chronic toxoplasmosis in the brain of mice using loop-mediated isothermal amplification (LAMP) and conventional PCR

BackgroundToxoplasma gondii is a common protozoan parasite that infects approximately one-third of the world's population. It is a disease with multiple manifestations. In immunocompetent individuals, symptoms are mild and flu-like, whereas, in immunocompromised patients, it often results in severe morbidity and mortality. Thus, studies for developing a simple, rapid diagnostic tool for early detection of Toxoplasma are emerging. Molecular diagnosis is highly accurate and helpful in congenitally infected and immunocompromised patients. The loop-mediated isothermal amplification (LAMP) technique was invented to improve nucleic acid amplification efficacy in terms of sensitivity and specificity. Aim of the studyThe study aimed to validate a LAMP protocol for detecting Toxoplasma DNA in the brain homogenates from mice experimentally infected with Toxoplasma's ME-49 (cyst-forming type II) strain in comparison to PCR. MethodsIn this study, the target DNA fragment was the Toxoplasma 529-bp, repeated 200–300 copies/genome. The sensitivity of both LAMP and conventional PCR techniques was estimated in brain homogenates in experimental mice at eight weeks post-infection and compared to the histopathology data. ResultsThe LAMP reaction showed positive results in 18 of the 26 examined samples of brain homogenates. PCR showed the characteristic 529-bp band in 15 of the 26 examined samples. ConclusionThe LAMP showed a higher sensitivity over PCR in detecting Toxoplasma infection in brain homogenates of infected mice.

The community knowledge, awareness, and practices influencing transmission of toxoplasmosis in Mbeya District, Tanzania

Background: Toxoplasmosis caused by Toxoplasma gondii is an important but neglected zoonotic disease of global distribution. The study aimed at evaluating community knowledge, awareness, and practices linked to transmission and control of the disease among the residents of urban and peri-urban areas of Mbeya District, Tanzania. Methods: A cross-section study was conducted from January 2022 to March 2022 in the Mbeya district. A semi-structured questionnaire was self-administered to gather information on social demographic characteristics, knowledge, and risk behaviors related to toxoplasma infection, chi squire was employed to test the difference where p-value &lt; 0.05 was considered statistically significant. Results: A total of 100 respondents were recruited. The majority (38.0%) of the respondents were aged 26 - 35 years and (49.0%) had attained primary education. The average mean age was 35.6 (+ 11.5 SD), 57% were male while 43.0% were female. Only 22 percent of the respondents were aware of toxoplasmosis and among them, 10 percent were aware of the clinical manifestations of the disease and 20 percent knew the mode of the disease transmission. Identified risk practices include lack of deworming in cats (81.0%), outdoor cats management (60.0%), disposal of cats' faces in gardens (36.0%), use of cats in controlling rodents (41.0%), and not wearing gloves during gardening (77.0%). Children are noted to be at the highest risk of contracting the disease as they are greatly involved in caring for cats. (49.0%). The knowledge of the disease was found to be associated with sex (males) p value= of 0.041, occupation (medical employees) p-value =0.002, and high level of education of the respondents' p value =0.000.\. Conclusion: The study revealed a low level of knowledge of the participants and practiced risky behaviors for disease transmission. Thus, we recommend to relevant authorities to offer education to the community concerning Toxoplasmosis.