ELECTROPHORETIC STUDIES ON ENZYMES OF THE SNAIL INTERMEDIATE HOSTS OF SCHISTOSOMA MANSONI FROM ETHIOPIA

ABSTRACT: Enzyme patterns of three populations of Biomphalaria pfeifferi and two populations of Biomphalaria sudanica from Ethiopia were studied by starch gel electrophoresis. The preliminary results indicated that four of the six enzyme systems investigated appeared potentially useful in discriminating between these closely related species. Acid-phosphatase, esternases, 3-hydroxybutyrate dehydrogenase and xanthine oxidase showed distinguishing characteristics either in terms of mobilities, or number of bands. The migration of acid-phosphatase was consistently faster in the B.sudanica populations than in any of the B.pfeifferi populations. Unlike acid-phosphatase, intraspecific variation among the populations of a species was observed for the esterases, 3hydroxybutyrate dehydrogenase and xanthine oxidase although clear differences were still apparent among these enzymes between B.sudanica and B.pfeifferi. The geographically closely located populations of B.pfeifferi from Wollo exhibited similar enzymatic activities but differed in most enzymes from the geographically separated population from Harar region. Further investigation is recommended to strengthen the present observatio

SURVEY OF INTERMEDIATE SNAIL HOSTS OF HUMAN SCHSTOSOMES IN RE-SE1TLEMENT SITES OF WESTERN ETHIOPIA

ABSTRACTFrom 29 January to March 1985, a field survey for the snail ,.ntermediate hosts of human schistosomes was conducted in 252 water bodies in 141 re-settlement sites in Wollega, Illubabor and Kafa Administrative Regions. Biomphalaria pfeifferi, the snail intermediate host for schistosoma mansoni, was collected from three water bodies in Wollega and from one water source in Kafa. The settlers in the re-settlement sites consisted of people from intestinal schistosomiasis endemic zones in the north. The habitats infested with Biomphalaria pfeifferi therefore need to be considered since they are potential foci for the establishment of the disease

Comparison of two concentration techniques in the detection of intestinal parasites

Abstract: The diagnostic performance of two concentration methods, Tween-80 and Formol-Saline, were evaluated using a total of 400 stool samples from patients referred to the Ethiopian Health and Nutrition Research Institute. Both tests showed similar rates of detection; Formol-Saline (50.3%) and Tween-80 (51%), and no significant difference was observed. The sensitivity and specificity of the Tween-80 method relative to the Formol-Saline technique were 97.0% and 95.5%, respectively. However, from the point of view of the relative availability of reagents and simplicity, the Formol-Saline concentration method is recommended for the diagnosis of intestinal parasites in basic service-giving health institutions and peripheral laboratories. [Ethiop. J. Health Dev. 1998;12(2):161-163

Comparative studies on two culture methods for hookworm species identification

Abstract: Ninety stool specimens obtained from patients referred to the National Research Institute of Health and found to reveal hookworm ova were cultured using the Test Tube Filter Paper and the Charcoal methods with a view to recover and identify the third stage larvae. Infective larvae were harvested in a total of 88(97.8%) specimens, 79(87.8%) of which were detected by both methods. Only 5(5.6%) and 4(4.4%) were exclusively detected by the Test Tube and Charcoal methods, respectively. Except in one specimen where filariforms of both species (Necator americanus and Ancylostoma duodenale) were encountered, N.americanus was dominant. Both methods exhibited no significant difference (P > 0.05) in the development capacity of third stage larvae. The importance of culturing hookworm species in relation to the understanding of species dominance and the merits and demerits of both methods are discussed.[Ethiop. J. Health Dev.1995;9(3):189-191

INTESTINAL PARASITISM AMONG THE STUDENT POPULATION OF THE WONJI-SHOA SUGAR ESTATE

ABSTRACT: Students from the five schools of the Wonji Shoa Sugar Estate had their stool specimens examined for intestinal parasites. The method of student selection was by the stratified simple random sample employed for each school. The formol ether concentration supplemented by the direct saline method was used to detect the diagnostic stages of the parasites. Of the 964 examined, 563 (58.4%) were found positive for one or more parasites. Significantly higher infection rate was noted in males than in females (p<0.001). Infection with multiple parasite species was observed in 48% of the positives. On the coverage, 1.7 parasite species per infected individual was recorded for all positive students. Of the ten parasites detected, the leading in order of their level of prevalence were; Ascaris lumbricoides (22.2%) Trichuris trichiura (19.5%), Schistosoma mansoni (15.4%) and Hookworm sp. (14.7%). The prevalence of the other parasites ranged from 0.7% (Enterobius vermicularis) to 6.7% (Giardia lamblia). While the frequency of infection with Schistosoma mansoni, Hookworm sp. and Strongyloides stercoralis were significantly higher in males than in females respectively (p<0.001, p<0.001, p<0.05) the reverse was true with Taenia sp. (p<0.05). The implications of the present findings with the possible lines of control are discussed

Intestinal parasitism among students in three localities in South Wello, Ethiopia

Abstract: A cross-sectional study to estimate the prevalence of intestinal parasites has been conducted in 1996 in South Wello in the towns of Kembolcha, Bati, and Mekaneselam. A total of 698 students were selected randomly by using the master list of the school as a sampling frame. The students were interviewed using a questionnaire on the use of toilets, sources of water for drinking, and purpose of washing. From the study subjects stool samples were collected and, screened for intestinal parasites using the Ritchie formol-ether technique. Of the examined, 304 (43.6%) were positive for various intestinal parasites. Schistosoma mansoni (24.9%) was commonest followed by Ascaris lumbricoides (18.3%) and Trichuris trichiura (4.4%). Other less frequent parasites were Hookworm Spp. (2%), Hymenolepis nana (1.3%), Giardia lamblia (1.1%), Strongyloides stercoralis (0.9%), Enterobius vermicularis (0.3%), and Trichostrongylus Sp. (0.1%). Prevalence of S.mansoni was significantly higher in males than in females (P<0.01); in the 10-14 year old than in the 15-19 and 20+ age groups (P<0.05), and among the Bati students than in those in Kembolcha and Mekaneselam (P<0.001). Markedly higher rates of Ascaris and Trichuris were observed in Kembolcha(P<0.01) than in Bati and Mekaneselam but showing no difference between males and females, and between the two age groups. The public health implications of intestinal parasites among school children and possible control measures are discussed. [Ethiop. J. Health Dev. 1998;12(3):231-235

Diarrhoea-associated parasitic infectious agents in AIDS patients within selected Addis Ababa Hospitals

Abstract: The aim of the study was to determine the prevalence of gastrointestinal parasites in Acquired Immunodeficiency Syndrome (AIDS) patients with chronic diarrhea. This prevalence was compared with two control groups: Human Immunodeficiency Virus (HIV) seronegative diarrheal patients and HIV seropositive individuals without diarrhoea. Stool specimens from clinically diagnosed hospitalized AIDS patients in some hospitals in Addis Ababa were screened for parasite infection. Of 147 AIDS patients with chronic diarrhoea, 74 (50.3%) were infected with one kind or more of parasites. Out of 56 non-AIDS (seronegative) diarrhoeal patients, 41.1% (23/56) and out of the 43 non-diarrhoeal (seropositive) patients, 41.9% (18/43) were infected by a variety of intestinal protozoa and helminths. The parasites detected in AIDS patients were Cryptosporidium spp, Isospora spp, Blastocystis spp, Ascaris lumbricoides, Giardia lamblia, Strongyloides stercoralis, Taenia spp, Trichuris trichiura, Entamoeba histolytica, and Hook worm spp. Among the intestinal parasites, Cryptosporidium spp was exclusively associated with AIDS patients. The high proportion of the study subjects who had diarrhoea in the absence of identifiable parasitic infections suggests that other infectious agents (eg. Bacteria and Virus) or mechanisms other than infectious agents, are responsible for the diarrhoea. [Ethiop. J. Health Dev. 1999;13(3):169-173

Intestinal parasitic infections in Western Abaya with special reference to Schistosomiasis mansoni

Abstract: A cross sectional investigation on the distribution and prevalence of intestinal parasitic infections was undertaken in Western Abaya, North Omo, in January 1995. As the area is potentially irrigable for modern agriculture, emphasis was placed to explore on the endemicity of schistosomiasis, including malacological assessments. Five percent of the whole population on 1473 people, in 16 villages of the area, were parasitologically examined for intestinal parasites. Among the intestinal parasitic infections, hookworm was demonstrated in all of the villages with prevalences ranging from 4.1% (Algie) to 75% (Wajifo). The majority of the villages (10/16=62.5%) had hookworm prevalences of over 50%. Schistosoma mansoni infections were found in 11 villages with prevalences of up to 53% with more males than females being affected (P<0.001). Infected Biomphalaria sudanica snails with infection rates of up to 2.1% at two sites of Lake Abaya were also found. The importance of the dominant, S. mansoni and hookworm infections in the potentially irrigable area of Western Abaya and feasible measures of their control are discussed. [Ethiop. J. Health Dev. 1999;13(1):21-26

Amoebic liver abscess: A 20-year retrospective analysis at Tikur Anbessa Hospital, Ethiopia

No Abstract Available Ethiop.J.Health Dev. Vol.18(3) 2004: 199-20

Optimization, Identification, and Quantification of Selected Phenolics in Three Underutilized Exotic Edible Fruits Using HPTLC

This study aimed to investigate selected bioactive components in three underutilized wild edible exotic fruits (Syzygium guineense Wild. DC, Ziziphus spina-christi L., and Citrus medica L.), using high-performance thin-layer chromatography and ultraviolet-visible spectrophotometry (HPTLC-UV-Vis), treated under three drying conditions. Ultrasound-assisted extraction was used to extract the target bioactive components under specified conditions, i.e., time of 15 min, temperature of 35 °C, methanol and water 75/25, v/v, and fruit powder-to-solvent ratio of 1:15, w/v. The mobile phase ratio for rutin, kaempferol, myricetin, and quercetin was toluene/ethylacetate/methanol/formic acid at 20:12:8:4, whereas, for phenolic acids, the ratio was 10:15:10:5, respectively. The HPTLC plates were scanned to identify and quantify selected compounds (phenolic acids, quercetin, rutin, myricetin, and kaempferol) at their maximum optimized absorption wavelengths. The contents of target bioactive components ranged from 0.64 ± 0.19 mg/100 g for rutin to 320.04 ± 7.10 mg/100 g for chlorogenic acid. Based on the results of this investigation, the phenol content of freeze-dried fruit was significantly (p ≤ 0.05) higher than other drying methods. The calculated average limit of detections and quantifications ranged from 0.37 to 75 ng/spot to 2.5 to 250 ng/spot, respectively. The average recoveries were 99.91 ± 5.65% for quercetin and 99.08 ± 5.96% for rutin. Overall, the validated HPTLC method was simple, selective, sensitive, and stable for the simultaneous identification and determination of phenolic acids and flavonoids. As a result, this study revealed that the contents of phenolic acids and flavonoids in selected exotic edible fruits can be used as effective antioxidants