الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 16 |  |  |
| | | from | 16 | | |
Abstract
G. lamblia is a protozoan parasite known to be an important waterborne pathogen. Giardia is a common cause of gastrointestinal disturbance in both high- and low-income countries.
The present study was designed to detect the overall prevalence of G. lamblia in children who attending the outpatient clinics of Assuit University Children Hospital, to assess the relation between G. lamblia infection and age factor and to evaluate the relation between seasonal variability and the prevalence of G. lamblia in children. 200 stool samples were collected during the period from January to August 2014. The samples were divided into: 100 samples from children 1-5 years old and100 samples from children 5-12 years old. All stool samples were examined by macroscopic examination, microscopic examination (direct smear and formol-ether concentration technique) and immuno-chromatographic test. G. lamblia cysts were isolated and concentrated from heavily infected fresh human stool containing no other parasites.
In vitro effects of dichloromethane extracts of ginger and turmeric in three concentrations (1, 10 and 50 mg/ml) were used for 5, 10, 30 and 60 min each. The effect of each extract was evaluated by viability testing (Eosin stain). In vivo effects of (dichloromethane) extracts of ginger and turmeric in doses of 10 and 20 mg/kg/day were assessed on experimentally infected mice. The in vivo effects were evaluated by daily faecal cyst count, intestinal trophozoite count after wash and histological examination of small intestinal sections after treatment by each extract separately. The present study was also designed to use flow cytometry for detection of G. lamblia cysts, its seasonal variability and viability assessment in water supplies of Assuit University Hospitals. 48 water grab samples (20 liter per sample) were collected from water supplies of hospital’s buildings from inlet, outlet and tanks during winter 2013-2014 and summer 2014. All water samples were subjected to filteration, elution and concentration before flow cytometry.
Results showed that the overall prevalence of G. lamblia among children was 30%. As regards age groups, the lowest positivity rate was detected in children 1-5 years old (10%). In contrast, the highest percentage of positive cases was detected in children aging 5-12 years old (50%) with highly significant difference (p<0.001). G. lamblia was detected in 5 samples (5 %) in winter and 55 (55%) in summer with highly significance difference between winter and summer (p<0.001). Comparing the three methods and techniques used to detect Giardia in this study, concentration technique gave the highest number of positive samples (n= 60), followed by the copro- antigen detection technique by using rapid solid phase qualitative immunochromatography (n= 57), lastly the direct examination (n= 50). However, the differences in positivity rates were not found to be statistically significant (P > 0.05).
As regard the in vitro effect of dichloromethane extract of ginger and turmeric on Giardia cysts; loss of its viability were observed at the concentration 50 mg/ml after 60 min, where 97 % and 85 % of the cysts were non-viable respectively. The antigiardial effect of all used concentrations of ginger and turmeric extracts was highly significant; when it was compared to the control groups; at all exposure times (p value<0.001). While in vivo study showed that ginger and curcuma cause reduction of faecal cysts and trophozoites count than the positive control group (infected untreated). This reduction was higher with both extracts when double the dose was used. Also morphological changes of giardia cysts were evident after exposure to both extracts. Histological damage in the small intestine induced by experimental giardia infection improved in all treated groups when compared to the infected untreated group. Results of both in vitro& in vivo studies confirm therapeutic effects of ginger and curcuma extracts on Giardia lamblia infection in mice as a promising alternative therapy to the commonly used antigiardial drugs.
In the present study; when water samples from water supplies of Assuit University Hospitals were examined; G. lamblia cysts were detected in 14 water samples out of 48 examined samples by flow cytometry with detection rate of (29.2%). The highest rate of positive samples was recorded in the winter while the lowest rate of positive samples was recorded in the summer. On the other hand the intensity of water contamination was higher in summer with mean of 1066.3 events (cysts)/L than in winter with mean of 837.1 events (cysts)/L. DAPI has detected the percent of cysts viability in the 48 samples, results showed statistically insignificant difference in regard to viability percent between winter (5.75%) and summer (6.2%). These results clearly demonstrate that the use of flow cytometry can detect Giardia cysts in water samples from water supplies. Although it is expensive, it is rapid, simple and accurate in estimating the quantity and viability of the parasites in each sample.
The present study revealed the need of these children for routine stool examination and treatment of infected children to get rid of Giardia infection to be able to grow well. from the results of the present study we recommended to use ginger and curcuma as a promising alternative to metronidazole due to antigiardial effect of these extracts. Further studies will be necessary to identify and isolate the active compound(s) accountable for their activity against G. lamblia. The present study confirmed the presence of viable Giar¬dia cysts in high numbers in drinking water supplies of the examined sites making people more exposed to the risk of acquiring the infection. These results revealed the need for efficient routine monitoring methods adapted by the water treatment facilities in this locality for water pollution by G. lamblia cysts for controlling the quality of drinking water. The results demonstrated the benefit of flow cytometry as rapid and simple method for evaluation of Giardia cysts in water samples.