An Assessment of the Epidemiology and In vitro Susceptibility of Giardia lamblia Trophozoites and Cysts to a Variety of Plant Extracts

Giardia lamblia is a prevalent intestinal parasite that cause diarrhea among human beings and the life cycle is complicated and contains two stages for trophozoites and cysts. These stages are hardly eradicated by using prescribed drugs such as metronidazole.

Aim: The purpose of this study was to identify the intestinal parasite Giardia lamblia in patients suffering from diarrhea and primary enteritis, then determine the antiparasitic activity of five plant extracts included (Zumeria majda, Thymus migricus, Artemisia santolina, Sargassum and Proskia) compared with available drug of metronidazole (MTZ) as an effective and first-time treatment against Giardia lamblia.

Place and Duration of Study: It was performed between January 2023 to February 2024 at the laboratory of parasitology of three hospitals included Ramadi Teaching Hospital, Fallujah Teaching Hospital and Ramadi Teaching Hospital for Maternity and Children in Al-Anbar governorate of Iraq. A total of 1200 stool samples of patients were collected from both genders and ranged in age from 6 months to 65 years.

Methodology: The stool samples were examined directly by formalin-ether test using a light microscope to confirm the presence of G. lamblia infection. Test tubes contained 1 mL of every extract at concentrations of 10, 25, 50, 75 and 100 µg/mL before 10,000 cysts or trophozoites were added and then the tubes were incubated at 37°C for a period of 30, 120, and 360 minutes. A light microscope set to 400x magnification, smears made from residual cyst and trophozoite material were arranged individually on glass slides. The mean number of the extracted cysts and trophozoites were assessed using vital 0.1% eosin staining.

Results: G. lamblia parasite infections accounted for 47.8% of all infections; males had a greater prevalence of the parasite (49.6%) than females (45.7%). In relation to other age groups, the incidences of G. lamblia infection were higher in the age groups of 6 months to 10 years and (11-20) years, at 55.17% and 47.6%, respectively. At the lowest concentrations of 75μg/mL and 100μg/mL following exposure times of 240 min and 360 min, all five plant extracts examined in this study included Zumeria majda, Thymus migricus, Artemisia santolina, Sargassum and Proskia had a significant effect and killed 100.0% of the cysts and trophozoites of G. lamblia in contrast to the MTZ, which showed the highest reduction rates 68.4% against cysts and 75.4% against trophozoites.

Conclusion: To conclude, the study findings indicate that G. lamblia infections are more common in AL-Anbar province particularly in younger people. This can be attributed to a number of factors such as improper eating and drinking habits and an absence of respect for hygiene and public health standards. Plant-based extracts showed promising in vitro activity at low doses and short times of exposure, according to the results on G. lamblia. These findings could lead to the development of a novel therapeutic alternative to treat Giardiasis infections.