Investigation of Giardia intestinalis Genotypes among the Food Handlers of Qazvin, Iran

BACKGROUND

We aimed to investigate the genotypes of Giardia intestinalis among the food handlers in Qazvin, Iran.

METHODS

Overall, 1530 stool specimens were collected from the food handlers who visited Shahid Bolandian Health Center, Qazvin, Iran during 2016. Specimens were evaluated by microscopic and concentration methods. Twenty specimens with appropriate number of giardia cysts were selected followed by DNA extraction. Determination of giardia genotypes was achieved through PCR and sequencing the glutamate dehydrogenase gene. The phylogenetic tree was drawn using the MEGA7 software. Finally, the data were analyzed statistically with a P-value<0.05 was considered as significant.

RESULTS

Twenty stool samples (1.3%) were positive for Giardia cyst. All positive specimens were obtained from male participants with abdominal cramp being their most common symptoms. The mean age for infected individuals was 32 yr. Molecular characterization was successfully performed for 17 isolates and two genotypes A (AII, 65%) and B (BIII, 35%) were identified.

CONCLUSION

The most prevalent giardia genotypes among the food handlers in Qazvin were A (AII) and B (BIII) genotypes with A (AII) genotype as the dominant one in the region. Considering the direct association between the food handlers and public health as well as the impact of geographical and host conditions on dispersion and pathogenicity of various genotypes and their zoonotic aspects, further investigations are necessary.

The necessity of confirmatory testing in serodiagnosis of toxoplasmosis in iran

BACKGROUND

Toxoplasma specific IgM antibodies; the common serologic marker in diagnosis of acute toxoplasmosis has its own limitations. Confirmatory testing with other markers, introduced as a complementary tool in distinguish acute and chronic infections is unusual in Iran. In the present study, we investigated the correlation between the results of IgM ELISA, IgA ELISA, and IgG avidity tests in the diagnosis of toxoplasmosis to demonstrate the necessity of confirmatory testing in serodiagnosis of infection in the country.

METHODS

A total of 107 positive Toxoplasma IgG and IgM sera were obtained from patients referred to private laboratories and stored at -20 °C for futures use. Serologic tests were set up in duplicate to analyze the serum levels of IgG, IgM, IgA, and IgG avidity antibodies using commercial ELISA kits. The results were presented as semi quantitative for IgG, IgM and IgA ELISA, and Relative Avidity Index in percentage for IgG avidity test. Pearson's correlation coefficient (rp) was applied to analyze the data.

RESULTS

Of 107 serum samples, T. gondii specific IgM and IgA antibodies were positive in 67.3% and 53.3%, respectively. Besides, 29.9% of the sera displayed low avidity for IgG antibodies. The rp was - 0.572 (P<0.01) between the IgG avidity and IgM ELISA, - 0.364 between the IgG avidity and IgA ELISA (P<0.01), and 0.564 between the IgM and IgA ELISA (P<0.01).

CONCLUSION

The study strongly highlights the necessity of confirmatory testing in differential diagnosis of acute and chronic toxoplasmosis in Iran.