Detection and genotyping of Toxoplasma gondii oocysts in environmental samples in Gaza, Palestine: A combined parasitological and molecular approach

Abstract

Objective: This study evaluated the prevalence and genotypes of Toxoplasma ( T.) gondii oocysts, the infectious environmental stage, in soil and water samples collected from Gaza, Palestine.
Methods: A total of 290 environmental samples (200 soil, 90 water) from diverse sites in Gaza, including Wadi Gaza, residential areas, markets, wells, and the main sewage plant. Samples were analyzed using polymerase chain reaction (PCR) and Sheather’s flotation, with genotyping via MseI endonuclease.
Results: Out of 290 environmental samples, 22 (7.6%) were positive by PCR and 31 (10.7%) were positive by Sheather’s flotation. The prevalence of T. gondii significantly varied by location, with residential yards showing the highest contamination and public squares and gardens the lowest. Among soil samples, 26 (13.0%) tested positive by Sheather’s method, while PCR detected contamination in 18 (9.0%). Water had lower contamination rates, with 4 (4.4%) testing positive by PCR and 5 (5.6%) by Sheather’s. All positive water samples were from Wadi Gaza. Genotyping confirmed all four tested samples belonged to T. gondii Type I.
Conclusions: The study demonstrated a statistically significant relationship between oocyst contamination prevalence and the source location of the samples. It concluded that T. gondii contamination is present in the soil and water in the study area, with soil showing higher contamination levels than water.

Keywords

Toxoplasma gondii / Oocysts / Genotyping / Soil / Water / Gaza

Conflict of interest statement

The authors declare that there is no conflict of interest.

Funding

This study received no extralmural funding.

Data availability statement

The data supporting the findings of this study are available from the corresponding author upon request.

Authors’ contributions

Dardona Z played the key role in data collection, composing the article, identifying relevant sources, writing, providing photographic documentation, and revising the text through linguistic and editorial editing. Al Hindi A, Hafidi M and Boumezzough A contributed to the research review, offered support in the writing process, funding and project administration. Sharif F contributed to PCR methodology and data analysis. Boussaa S supervised the entire project, performed a comprehensive review, managed communication with the journal, and provided significant assistance in writing, data collection, and editing. All authors read and approved the final manuscript.

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