Diagnostic and epidemiological study of Toxoplasma gondii for students of Thi-Qar University by ELISA and Real-Time PCR techniques

Abstract EN

Toxoplasmosis is caused by an obligate intracellular tissue protozoan parasite Toxoplasma gondii, which is able to infect humans as well as other warm blooded domestic and wild animals.

The infection has a world-wide distribution with approximately one-third of the world population estimated to be exposed to this parasite The present study was performed for the first time in Thi-Qar province to estimate the prevalence of toxoplasmosis among the university students.

Blood samples were collected from 319 (111 males and 208 females) apparently healthy students, they have ages between (18-42) years attended from different colleges of Thi-Qar university (students of morning and evening study), during the period from October 2013 to April 2014.

Enzyme linked Immunosorbant Assay (ELISA), was used to evaluate the presence of anti-Toxoplasma IgM and IgG antibodies and detection of B1 gene of T.gondii DNA by Real-Time Polymerase Chain Reaction (RT-PCR).

The results indicated that 21.94% of students were anti-Toxoplasma antibodies using ELISA test.

The study demonstrated that no significant difference in infection percentages between colleges where students studied, although the highest seropositivity students was 47.83% in Education Sports College whereas it did not score any infection with toxoplasmosis in College of Education for Pure Science .

The current study also showed that the highest positive percentage with T.gondii of male students was 28.57% in College of Engineering while the highest percentage with T.gondii of female students was 30.43% in College of sports education.

The present study revealed that the acute infection of toxoplasmosis which presented IgM and both IgM and IgG was high at small age young students (18-22) years while the chronic infection which presented IgG was high at old students (38-42) years.

The present study demonstrated that seroprevalence of toxoplasmosis was significantly associated with close contact with cats.

The present study revealed an association between blood group system and Toxoplasma infection with highest prevalence among samples of blood group AP+P 30.65% and lowest prevalence in samples of blood group BP+P 17.44%.

Besides the serological diagnosis of T.gondii, Real-Time PCR (RT-PCR) technique was used to confirm the infection with T.gondii by detection B1 gene of T.gondii DNA in the blood of students.

Out of 319 students only 6.26% showed positive for toxoplasmosis among those 2.50% were males and 3.76% were females.

The positive result in RT-PCR analysis were distributed on the patterns of the antiToxoplasma antibodies by ELISA test , Any positive blood samples with IgM, IgG and both IgM and IgG respectively have not been found whereas 20 positive cases of no anti –Toxoplasma antibodies.

Real-Time PCR test in student's blood has advantages in detection of recent or active toxoplasmosis