Genotyping of Toxoplasma gondii Isolates from Soil Samples in Tehran,Iran

Background

The protozoan parasite Toxoplasma gondii can infect any warm blooded nucleated cells. One of the ways for human infection is ingestion of oocysts directly from soil or via infected fruits or vegetables. To survey the potential role of T. gondii oocyst in soil samples, the present study was conducted in Tehran City, Iran.

Methods

A total of 150 soil samples were collected around rubbish dumps, children''s play ground, parks and public places. Oocysts recovery was performed by sodium nitrate flotation method on soil samples. For molecular detection, PCR reaction targeting B1 gene was performed and then, the positive results were confirmed using repetitive 529 bp DNA fragment in other PCR reaction. Finally, the positive samples were genotyped at the SAG2 locus.

Results

Toxoplasma DNA was found in 13 soil samples. After genotyping and RFLP analysis in SAG2 locus, nine positive samples were revealed type III, one positive sample was type I whereas three samples revealed mixed infection (type, I & III).

Conclusion

The predominant genotype in Tehran soil samples is type III.     

Seroprevalence of Toxoplasma gondii in Pregnant Women and Bioassay of IgM Positive Cases in Zanjan,Northwest of Iran

Background

The aim of this study was to determine the Toxoplasma antibodies in pregnant women in Zanjan, by ELISA method.

Methods

Blood samples were taken from 500 pregnant women referred to the health centers of Zanjan City, North West Iran, IgM and IgG titers were primarily evaluated. The collected data were analyzed with SPSS 11.5 using Chi-Square test.

Results

Anti Toxoplasma IgM and IgG were positive in 1.4% and 37.2% respectively. Seropositive subjects were more frequently seen in those with >30 years old compared to younger women (<20 years old). No significant relationship was found between the seroprevalence of T. gondii infection and level of education, residence area, history of abortion and gestational age.

Conclusion

The rate of IgM positive was low; however, a large number of the studied population were IgG positive, indicative of having a latent infection due to the past exposure to Toxoplasma parasite in this region.     

High Seroprevalence of Toxoplasma gondii Antibody in HIV/AIDS Individuals from North of Iran

Background:

Toxoplasmosis in immunocompetent people is generally asymptomatic but in immunocompromised patients including HIV/AIDS, cancer patients, and organ transplant recipients, etc. it can lead to serious pathological problems. The objective of current study was to determine the seroprevalence of T. gondii IgG and IgM antibodies in HIV/AIDS patients using ELISA technique in Mazandaran Province, northern Iran.

Methods:

Overall, 82 serum samples (61 males and 21 females) were collected from HIV/AIDS patients in Mazandaran Provinces, in 2013. Sera were surveyed employing ELISA assay. Data were analyzed using Chi-Square or Fisher exact test. In addition, before sampling a questionnaire was filled out for each subject.

Results:

Overall seroprevalence of examined sera was 96.3% for IgG antibody but none of the sera shown IgM antibody against T. gondii. The seroprevalence of toxoplasmosis in males and females was 96.7% and 95.2%, respectively. An antibody titer of >1 IU/ml was considered as positive. Furthermore, none of the included variables statistically was significant.

Conclusions:

Seroprevalence of chronic (latent) toxoplasmosis in HIV/AIDS patients in Mazandaran Province is high compared to toxoplasmosis in general population. Consequently, the risk of acquiring Toxoplasma encephalitis in examined seropositive HIV/AIDS patients of Toxoplasma is high.     

Seroprevalence of Toxoplasma gondii Infections in Pregnant Women in Gorgan City,Golestan Province,Northern Iran-2012

Background

Toxoplasma gondii is one of the most prevalent parasites of human and warm- blooded animals. Toxoplasmosis is important especially in two groups: pregnant women and immunocompromised patients. If women acquire the primary infection during the pregnancy, it would be life threatening or remains severe disorders for the fetus. This study was performed to evaluate the seroprevalence of T. gondii infection in pregnant women referred to Health Center in Gorgan City, Golestan Province, northern Iran.

Methods

Serum samples were collected from pregnant women referred to Health Center in Gorgan City, south eastern Caspian Sea. Anti- Toxoplasma IgG and IgM antibodies were determined by commercially ELISA kits and the relation of infection with socio-demographic and risk factors such as age, education, occupation, cat ownership, soil contact and some other factors was studied.

Results

From 555 tested sera of pregnant women referred to Health Center in Gorgan, 39.8% had IgG antibodies against T. gondii and 3.4% were positive for IgM antibodies. A significant correlation was seen between T. gondii infection with age and soil contact.

Conclusion

About 60% of pregnant women in Gorgan City are seronegative against T. gondii, so they should considered as at risk persons.     

Molecular Survey of Toxoplasma gondii in Sheep,Cattle and Meat Products in Chaharmahal va Bakhtiari Province,Southwest of Iran

Background

Toxoplasmosis is a worldwide spread disease. The present study examined the prevalence of Toxoplasma gondii infection among animals of edible meat (cattle and sheep) in Chaharmahal va Bakhtiari Province (Southwest of Iran) in 2012. Furthermore, we attempted for the first time to identify this parasite from the meat products in the province.

Methods

The tongue, brain, femur muscle and liver of 50 sheep and 70 cattle as well as 50 samples of meat products were selected and collected to perform molecular survey using Nested-PCR method.

Results

Of the studied sheep, 38% were infected. The infection rate in the age groups under 1 year, 1-2 years, and more than 2 years was 25%, 35.29% and 52.94%, respectively. The infection rate in femur muscle, brain, liver and tongue was 28%, 32%, 30% and 16%, respectively. Of the studied cattle, 8.57% were infected. The infection rate in the age groups 1-2 years, 2-4 years, and more than 4 years was 3.7%, 9.09% and 14.28%, respectively. Sheep was infected 6 times more than cattle (OR = 6.53 CI = 2.374-18.005).The infection rate among samples of meat products was 12% (6 samples out of 50 samples).

Conclusion

Due to the high rate of this parasitic infection among the slaughtered animals as well as meat products in this region, the use of infected material can be one of the main risk factors of transmission of the parasite to humans.     

Seroprevalence and Risk Factors of Toxoplasma gondii Infection in Buffaloes,Sheep and Goats in Yunnan Province,Southwestern China

Background:

The seroprevalence of Toxoplasma gondii infection in buffaloes, sheep and goats in Yunnan Province, southwestern China was conducted between May 2012 and December 2013.

Methods:

A total of 973 (427 buffaloes, 154 sheep and 392 goats) serum samples were collected from seven administrative regions of Yunnan Province, and examined for T. gondii antibodies by indirect hemagglutination (IHA) test. Some risk factors related to species, age, gender and geographical origin were determined using a multinomial logistic regression.

Results:

The overall seroprevalence of T. gondii in ruminant species was estimated at 11.9%. The final logistic regression model demonstrated that host species and geographical origin were the main risk factors associated with T. gondii infection (P<0.05).

Conclusion:

Taken together, the results of the present study revealed a high exposure to T. gondii in ruminant species in Yunnan Province, which has an important implication for public health.     

Comparison of a Commercial ELISA with the Modified Agglutination Test for Detection of Toxoplasma gondii Antibodies in Sera of Naturally Infected Dogs and Cats

Background

Toxoplasma gondii can infect all warm-blooded animals. Modified agglutination test (MAT) and ELISA are widely used for the detection of T. gondii antibodies. However, there is little information on their acceptability for detecting antibodies in companion animals.

Methods

This study compared ELISA and MAT for their ability to detect T. gondii infection in naturally infected dogs and cats. Blood samples were collected from dogs and cats in different areas of Beijing, China and analyzed by ELISA and MAT. The χ² test and κ analysis were used to evaluate their efficiency and agreement.

Results

For dogs, the seroprevalence of T. gondii antibodies detected by ELISA was 34.7%, which was significantly higher than that detected by MAT (P<0.05). There was no significant difference between ELISA and MAT for detecting T. gondii antibodies in cats. Good agreements between MAT and ELISA were seen in both dogs and cats; however, inconsistent results were demonstrated by κ analysis and in MAT titer assay.

Conclusion

Serum-based ELISA may be more satisfactory for screening test of T. gondii infection in dogs, whereas both methods could be acceptable in cats.     

Detection and Identification of Toxoplasma gondii Type One Infection in Sheep Aborted Fetuses in Qazvin Province of Iran

Background

The aim of this study was to apply the nested-PCR and bioassay methods in detection and genotyping of Toxoplasma gondii infection in provided sheep aborted fetus samples from Qazvin Province of Iran.

Methods

Eighteen sheep aborted fetal samples were studied by nested-PCR-RFLP, histopathological observation and microbiological assay. Bioassay in mice was carried out by inoculating the brain samples intraperitoneally.

Results

The results demonstrated the frequency of 66% infected sheep aborted fetal samples with T. gondii type one. Although we could not isolate any parasite from inoculated mice even after three passages, but it was confirmed histopathologically formation of cyst like bodies in prepared mice brain sections.

Conclusion

The results of the performed nested-PCR and formation of brain cyst in inoculated mice exhibited that T. gondii type one infection might be considered as one of the major causative agents for abortion in ewes.     

Seroprevalence of Toxoplasma gondii in Sheep,Cattle and Horses in Urmia North-West of Iran

Background

Toxoplasma gondii is a zoonotic protozoan parasite found worldwide and responsible for major economic losses in most classes of livestock. This study was aimed to determine the prevalence of T. gondii infection in sheep, cattle and horses in Urmia, north-west of Iran, using MAT.

Methods

Blood samples of 276 livestock and 26 horses were collected from July 2009 till April 2010. The data were analyzed by the Chi-square, Fisher''s Exact and Cochran''s and Mantel-Haenszel Tests. The level of significance was set at P<0.05.

Results

Thirty-three (21.1%) sheep, 2 (1.6%) cattle and 3 (11.5%) horses were seropositive to T. gondii. Analysis showed that sheep were 15 times more likely to be seropositive comparing to cattle also 2 times more likely to be seropositive than horses.

Conclusion

This study showed seroprevalence of equine T. gondii infection with a considerable rate in sheep in Urmia, northwest of Iran. More comprehensive studies on livestock toxoplasmosis are required for further analysis of the parasite reservoir for human infection.     

Effects of Toxoplasma gondii Infection in Level of Serum Testosterone in Males with Chronic Toxoplasmosis

Background

Toxoplasma gondii is an intracellular protozoan parasite that infects human and animals. Toxoplasma parasites are isolated from different parts of animals even from semen but there are little information about the effect of toxoplasmosis on fertility in animals and humans. In present study, the effect of chronic toxoplasmosis on serum levels of testosterone in men was studied.

Methods

In this case-control study, 1026 men referred to Arak Post Marriage Center were selected. Three ml of blood samples were collected and sera separated by centrifugation at room temperature. These sera were analyzed for detection of anti-T. gondii IgG antibody. Next 365 positive sera were selected as cases and also the same number of negative sera (365) as controls. Finally the level of testosterone was analyzed for the cases and controls samples.

Result

Serological tests on the sera of 1,026 men in Arak City showed that 365 of them had anti-Toxoplasma antibody. Comparison of testosterone concentration in case and control groups showed that testosterone concentration in case group was less than control group and this difference was statistically significant (P<0.05).

Conclusion

The chronic toxoplasmosis could affect reproductive parameters in men.     

Conjugated Linoleic Acid Stimulates Apoptosis in RH and Tehran Strains of Toxoplasma gondii,in Vitro

Background:

The aim of this study was to evaluate the effects of conjugated linoleic acid (CLA) on apoptosis of tachyzoites of T. gondii, RH strain (type I) and the cyst-forming Tehran strain (type II) in vitro.

Methods:

Toxoplasma strains were injected into the peritoneal cavity of BALB/c mice. The Tehran strain forms cysts in the brain of mice. Bradyzoites within the cysts are reactivated to proliferative tachyzoites, by dexamethasone. Tachyzoites were aspirated from the peritoneum of infected mice, and the percentage of viable parasites was estimated with trypan blue staining. Tachyzoites were inoculated into HeLa cells cultivated in DMEM medium. Different concentrations of CLA were evaluated on T. gondii in HeLa cells by the tetrazolium (MTT) colorimetric assay. Differentiation between apoptosis and cell death was determined by flow cytometry using Annexin V and propidium iodide (PI) double staining. The statistical analysis performed by GraphPad Prism version 6.00.

Results:

CLA induces apoptosis in virulent (RH) and avirulent (Tehran) strains of T. gondii. The results of MTT indicated that CLA could decrease the proliferation of tachyzoites of both strains in HeLa cells.

Conclusion:

Conjugated linoleic acid has anti-toxoplasmacidal activity on tachyzoites of T. gondii. Therefore, we recommended further studies on this component in order to achieve a new drug against the parasite.     

Elevated Toxoplasma gondii Infection Rates for Retinas from Eye Banks,Southern Brazil

We found significantly higher incidence of Toxoplasma gondii DNA in eye bank specimens from Joinville in southern Brazil (13/15, 87%) than in São Paulo (3/42, 7%; p = 2.1 × 10E–8). PCR DNA sequence analysis was more sensitive at locus NTS2 than at locus B1; a high frequency of mixed co-infections was detected.     

Toxoplasma gondii infection in the United States, 1999-2000

Infection with Toxoplasma gondii can lead to congenital and acquired disease, resulting in loss of vision and neurologic illness. We tested sera collected in the National Health and Examination Survey (NHANES) from 1999-2000 for T. gondii-specific immunoglobulin G antibodies and compared these results with results from sera obtained in the NHANES III survey (1988-1994). NHANES collects data on a nationally representative sample of the U.S. civilian population. Of 4,234 persons 12-49 years of age in NHANES 1999-2000, 15.8= (age-adjusted, 95% confidence limits [CL] 13.5, 18.1) were antibody positive; among women (n = 2,221) 14.9= (age-adjusted, 95% CL 12.5, 17.4) were antibody positive. T. gondii antibody prevalence was higher among non-Hispanic black persons than among non-Hispanic white persons (age-adjusted prevalence 19.2% vs. 12.1%, p = 0.003) and increased with age. No statistically significant differences were found between T. gondii antibody prevalence in NHANES 1999-2000, and NHANES III. T. gondii antibody prevalence has remained stable over the past 10 years in the United States.     

A Preliminary Parasitological Survey of Hepatozoon Spp. Infection in Dogs in Mashhad,Iran

Background

We attempted to determine the prevalence of Hepatozoon spp. infection in Mashhad, northeast of Iran, via blood smear parasitology.

Methods

The prevalence was investigated by examination of blood smear parasitology, using blood samples collected from 254 dogs (51 strays and 203 privately owned-dogs).

Results

Two stray dogs (2/51; 3.92%) and two privately-owned dogs (2/203; 0.98%) were infected with Hepatozoon spp. Therefore, as per blood smear parasitology, the prevalence of Hepatozoon spp. infection was 1.57% (4/254). Sixteen out of 254 dogs (6.29%) were infested with ticks; all of which were Rhipicephalus sanguineus. One of the dogs infected with Hepatozoon spp. exhibited ticks at the time of examination. Concurrent infection with Ehrlichia canis and Leishmania infantum was not detected in the four Hepatozoon spp. infected dogs.

Conclusion

This is the first epidemiological study on the prevalence of Hepatozoon spp. infection in dogs in Iran.     

Frequency of Toxoplasma gondii in HIV Positive Patients from West of Iran by ELISA and PCR

Background

Toxoplasma gondii, the obligate intracellular parasite is life threatening in AIDS patients. Diagnosis of toxoplasmosis is based on serological methods especially increasing of IgM and IgG titers, but finding of parasite or its components (antigenemia) may be beneficial method in order to detection of acute toxoplasmosis in immunocompromised patients.

Methods

Ninety-four serum samples from HIV positive patients were collected from Sanandaj, Kordistan west of Iran. These patients were lived in Sanandaj of whom 26 were prisoners infected with HIV virus in prison. Toxoplasma gondii antibodies were determined by IgG ELISA. T. gondii antigen was identified by capture-ELISA. PCR was performed on samples with T. gondii antigenemia. CD4+ T cells counts had been determined by flowcytometry and were obtained from records of each patient.

Results

Among the examined HIV seropositive individuals, 19.1% (18/94) and 5.3% (5/94) were positive for Toxoplasma-IgG and antigenemia, respectively. Besides, one of the samples was positively detected by PCR method. Mean age of participants was 37.9 ± 9.5 year. Prevalence of IgG antibody and antgenemia was higher in age group of 40-50 years old. The Mean of CD4+ T cells counts of participants (total of HIV+ patients, IgG positive patients and patients with antigenemia) was 699.2 ± 345.2, 655.1 ± 237.9 and 620.2 ± 215.1 respectively.

Conclusion

Capture-ELISA and PCR could confirm the T. gondii acute infection in HIV positive patients. For precise diagnosis of acute toxoplasmosis in HIV positive patient, performance of more studies based on more sensitive types of PCR is suggested.     

Seroprevalence of Acanthamoeba Antibodies in Rheumatoid Arthritis Patients by IFAT,Tehran, Iran 2007

Background

This preliminary study was conducted to discriminate the prevalence of Acanthamoeba antibodies in rheumatoid arthritis (RA) patients and healthy controls to analyze the correlation between these two groups.

Methods

From October 2006 to August 2007 a total of 121 serum samples from RA patients attending the Rheumatolgy Department at Shariati Hospital in Tehran were obtained and stored at -20°C until using by indirect fluorescent-antibody test (IFAT). RA was diagnosed according to the American Collage of Rheumatology classification criteria. The organism used in this study was isolated from various water resources in Tehran, Iran cultured axenically and then went on a PCR assay based on 18S rRNA to identify the genus Acanthomoeba. Indirect immunofluorescence antibody (IFA) staining of serum samples was carried out to detect anti Acanthomoeba antibodies.

Results

In culture, out of 22 samples, 13(59%) were grown in xenic but only two in axenic medium. PCR amplified a 904bp fragment, specific for Acanthamoeba. Of examined serum samples, Acanthamoeba antibodies were present in 70 (57.8%) and 52 (41.2%), respectively. The highest titer of antibodies (1:320) was detected in one patient with RA.

Conclusion

Our study supports the hypothesis that some parasitic microorganisms can involve and contribute toward the development of rheumatoid syndromes.     

Seroprevalence and Associated Risk Factors of Toxoplasma gondii in Pregnant Women Attending in Northwest Ethiopia

Background

Toxoplasmosis is a major public health problem among immuno-compromised individuals. This study aimed to determine the seroprevalence and associated risk factors of Toxoplasma gondii infection among pregnant women with and out HIV infections.

Methods

This cross sectional study was conducted among consecutive 385 pregnant women attended Antenatal Clinic from May 2010 to October 2011 at the Gondar University Teaching Hospital, Northwest Ethiopia. Venous blood was collected from each pregnant woman for testing HIV-1/2 and anti- Toxoplasma antibodies using rapid test kits. Data were entered and analyzed using SPSS version 20 statistical package.

Results

The overall magnitude of T. gondii and HIV was 88.6% (341/385) and 11.2% (43/385), respectively. The seroprevalence of T. gondii was not different among HIV infected and non-infected pregnant women (88.4%, 38/ 43 vs 88.6%, 303/342). Keeping cats in house showed statistically significant association with seropositivity of toxoplasmosis (P<0.05).

Conclusion

Irrespective of HIV infection, high rate of T. gondii was detected among pregnant women. These high prevalences indicate the need for an intensified public health awareness to reduce both infections.     

Rapid Detection of Toxoplasma gondii Antigen in Experimentally Infected Mice by Dot- ELISA

Background

Toxoplasmosis is a worldwide endemic disease. In congenitally infected infants and AIDS patients, toxoplasmosis causes high rates of morbidity and mortality. In these cases antibody detection is difficult; so detection of parasite or its components could be useful tool for early detection and following treatment of the infection.

Methods

Sixty-three BALB/c mice were injected intra-peritoneal with 5×10³ tachyzoites of Toxoplasma gondii RH strain, nine mice were sacrificed daily for 7 days. Fourteen mice were injected with phosphate buffer saline as control group. Dot–ELISA was performed for detection of T.gondii antigen in mice sera and capture – ELISA was done as golden standard assay too.

Results

Toxoplasma gondii antigen was detected from day 2 in mice sera; 22% of mice sera on day 2, 33% on day 3,77% on day 4 and 100% on day 5 till their death on day 7 had shown antigenemia by dot – ELISA, no positive result was detected in control mice by dot- ELISA.

Conclusion

Dot-ELISA is a sensitive method for diagnosis of T. gondii infection in the animal model; also, this technique is more rapid and easy to perform method in comparison with capture-ELISA.     

Toxoplasma gondii infection in pregnant women in China

Infection with Toxoplasma gondii is common and usually asymptomatic, but it can have serious consequences in pregnant women if passed to the developing fetus. The aims of this study were to determine the prevalence of toxoplasmosis in pregnant women and to identify the possible risk factors associated with T. gondii infection in China. Of a sample of 235 pregnant women in Changchun, China, 25 (10.6%) were found by ELISA to be positive for IgG and none (0%) for IgM. Major risk factors were found by bivariate and multivariate analysis to include eating raw or undercooked meat, unwashed raw vegetables or fruit, contact with cats, living in rural areas, and low educational standards. In order to lower congenital infection, pregnant women need to be informed about the risk factors for toxoplasmosis.     

Production and Evaluation of Toxoplasma gondii Recombinant Surface Antigen 1 (SAG1) for Serodiagnosis of Acute and Chronic Toxoplasma Infection in Human Sera

Background

The assays currently available for the detection of specific anti-Toxoplasma antibodies may vary in their abilities to detect serum immunoglobulins, due to the Lack of a purified standardized antigen. The aim of this study was evaluation the recombinant Toxoplasma gondii SAG1 antigen for the serodiagnosis of acute and chronic toxoplasmosis.

Methods

This study describes an ELISA using recombinant SAG1 for detection of IgM and IgG antibodies against Toxoplasma gondii in human sera. Genomic DNA of T. gondii (RH Strain) was isolated and PCR reaction was performed. Recovered DNA was cloned into PTZ57R cloning vector. The recombinant plasmid was detected by restriction analysis. The SAG1 gene was subcloned in the pET- 28a expression vector. Protein production was then induced with 1 mM isopropyl-D – thiogalactopyranoside (IPTG). A total of 204 sera were tested using a commercial IgG and IgM ELISA kit (Trinity, USA) as gold standard prior to testing them with the recombinant antigen.

Results

Tested sera were divided into the following groups:(a) The 74 T. gondii IgG positive (b) 70 T.gondii IgM positive (c) 60 sera who had no serological evidence of toxoplasmosis as negative sera.To determine the specificity of the test, we used other parasitic diseases including echinococusis (N=5), malaria (N=14), leishmaniasis (N=7),fasciolasis (N=4), sterengyloidiasis (N=1). Sensitivity and specificity of the generated recombinant IgG ELISA in comparison with commercial ELISA (Com ELISA) were 93% and 95%, and the sensitivity and specificity of the generated recombinant IgM ELISA were 87% and 95% respectively.

Conclusion

The results acquired here show that this antigen is useful for diagnostic purposes and could be replaced by lysed, whole cell antigens for diagnosis of chronic toxoplasmosis.