Browsing by Author "Gadisa Endalamaw"

Now showing 1 - 4 of 4
  • No Thumbnail Available
    Item
    Comparative Assessment of Microscopy, Malaria Rapid Diagnostic Test and Polymerase Chain Reaction as Diagnostic Test Tools in Adama Woreda, East Shoa Zone of Ethiopia
    (Addis Ababa University, 2017-08) Tegegne Getaneh; Gadisa Endalamaw
    Background: One of the main challenges in controlling morbidity and mortality caused by malaria is limited access to effective diagnosis in areas where malaria is endemic. This study was designed to compare the performance of CarestartTMpf/pan RDT, Giemsa microscopy and 18S nested PCR for the diagnosis of malaria. Methods: Health facility and community based cross-sectional study was conducted from December ,2016 to February, 2017 in villages of Batodegama kebele and at Adama malaria control center located in Adama woreda, East Shoa Zone of Oromia Regional State. A total of 330 residents (202 suspected malaria cases and 128 healthy individuals without any symptom) were enrolled in this study. Finger prick blood samples were taken from each participant, for CarestartTM pf/pan RDTtest, Giemsa microscopy and Dry Blood Spot (DBS) for 18S nested PCR assay. Result: From 128 asymptomatic, participants, 20.3 %, 6.3 % and 3.9 % were positive with nested 18S PCR, Giemsa microscopy and RDT respectively. Similarlly from 202 symptomatic participants malaria parasite were detected in 27.2 %, 13.9 % and 12.9 % by 18S nested PCR, Giemsa microscope and RDT respectively. As compaired to Giemsa microscopy; CarestartTMpf/pan RDT perform equivalent 100.0 % for all parameters (sensitivity, specificity, positive predictive value (PPV) and a negative predictive value (NPV)) for the diagnosis of symptomatic malaria infections, where as in detecting asymptomatic cases, it had a lower sensitivity (62.5 %). While comparing Giemsa microscopy and CarestartTMpf/pan RDT with 18S nested PCR to diagnose symptomatic malaria infections both presented an equivalent sensitivity of 50.0 %, specificity of 100.0 %, positive predictive value (PPV) of 100.0 % and negative predictive(NPV) value of 84.6 % and in detecting asymptomatic malaria infections, the CarestartTMpf /pan RDT presented a sensitivity of 15.4 %, a specificity of 98.0 %, a positive predictive value (PPV) of 66.7 % and a negative predictive value (NPV) of 82.0 %. Giemsa microscopy presented a sensitivity of 19.2 %, a specificity of 97.1 %, a positive predictive value (PPV) of 62.5 % and a negative predictive value (NPV) of 82.5 %. Conclusion: The performance of CareStart TM pf/pan RDT and Giemsa microscopy was comparable and both of them had significantly lower sensitivity compaired to 18S nested PCR.
  • No Thumbnail Available
    Item
    A Hybrid Approach to Screen A Sentinel Population to Identify Clusters of Sub-Patent Malaria Infections in Low Endemic Setting In Batu Degaga Kebelle, Adama Woreda, Oromia, Ethiopia
    (Addis Ababa University, 2017-10) Belachew Mulualem; Gadisa Endalamaw
    Background: As the incidence of malaria decreases the distribution of malaria becomes highly heterogeneous and concentrated in certain geographical areas and households. Due to this the risk of being infected by malaria becomes highly variable within the same locality and households. Identifying the distribution patterns of malaria is crucial in the control as well as elimination of malaria. Methods: A cross sectional survey was carried out targeting a total of 18 rapid diagnostic test(RDT)-confirmed malaria infected and 18 individuals that visited the health-post for malaria unrelated cases between October and December 2016 including their immediate six neighbors and family members. Consenting individuals were screened for malaria using RDT and dried blood spots were collected for quantification of parasites using species specific 18S based quantitative polymerase chain reaction (qPCR). Spatial clustering of malaria infections was assessed using SaTScan Software. Results: RDT-detected malaria (any species) was higher in the community around index cases compared to controls (P = 0.001). Asymptomatic qPCR-detected P. falciparum infections were higher in the community around index cases (13.9%) compared to controls (9.5%; P = 0.038) while the distribution of qPCR-detected P. vivax was similar (P = 0.926). Children had the highest burden of malaria and carry high density infections compared to adults. SaTScan detected four geographically non-overlapping significant hotspot of any malaria cases with relative risk of 2.11, 1.9, 1.89 and 1.86. Individuals who lived in households (HHs) within at risk areas were more likely to have previous malaria episodes (33.1%, 177/233) compared to individuals in HHs outside risk areas (1.5%, 3/203; odds ratio [OR], 32.9; 95% CI, 10.2– 106.3). People in risk areas utilize malaria control interventions better than people in HHs outside of risk areas and live in iron sheet houses with eave openings and better HH facilities. HHs within the clusters of higher malaria incidence was closer to water bodies and farther from health posts. People who lived in HHs at risk areas walk in the night, enter their houses late and leave their houses early than people who lived in risk free areas. Conclusion: The distribution of malaria was heterogeneous and clustered in the study district. Symptomatic and asymptomatic malaria distributed significantly around index cases compared to non-malaria control cases. Malaria control and elimination strategies of the country might benefit by targeting hotspots of malaria by following patients. Hot spot population carries the biggest burden of malaria and they might contribute disproportionately to the onward maintenance of malaria infections even outside of the risk areas. VIII Key words: Cluster, Asymptomatic, Heterogeneous, qPCR Sat Scan Key words: Cluster, Asymptomatic, Heterogeneous, IX qPCR Sat Scan
  • No Thumbnail Available
    Item
    The Prevalence of Glucose-6-Phosphate Dehydrogenase Deficiency among Apparently Healthy Individuals in Selected Malaria Endemic Areas from Different Agroecological Zones of Ethiopia using Phenotyping and Genotyping approaches
    (Addis Ababa University, 2017-09) Shitaye Getasew; Gadisa Endalamaw
    Background: - Glucose-6-phosphate dehydrogenase deficiency (G6PDd) is common in malaria endemic regions that hinder the use of 8-aminoquinoline drugs as a radical cure for malaria due to the risk of inducing hemolytic anemia. Objective: - To investigate G6PDd among apparently healthy individuals in selected malaria endemic areas from different agroecological zones of Ethiopia. Methods: - a community based cross sectional survey involving 1609 individuals was done using genotypic and phenotypic analysis. CareStart™ Rapid Diagnostic kit (RDT) was used to screen for G6PD enzyme activity. Sequencing and polymerase chain reaction based restriction fragment length polymorphism were done for further confirmation for all phenotypically detected enzymatic deficiencies and screened representative samples from those which tested phenotypically normal. Dried Blood Spot was collected for molecular analysis. Phenotypically deficient individuals were genotyped for the mutations, G202A, A376G and C563T. Plasmodium blood-stage parasitaemia detection was performed using the CareStart™ Malaria Ag PLDH/HRP2 and nested Polymerase Chain Reaction. Results: - G6PDd detected using the phenotypic approach was less (22/1609, 1.4%) than the genotypic approach (31/222, 14%). Of the 22 G6PDd individuals detected by CareStart™ RDT, 13 (1.50%) males and 9 (1.21%) females, 16/400 (4.00%), 4/484 (0.8%) and 2/401 (0.5%) were from Gambella, Oromiya and Benishangule Gumuz respectively. Moreover, the G6PDd phenotypic prevalence was significantly higher 6.50 % (13/200) in the Agnuwak ethnic groups (x2 =47.3431 and P = 0.001). Of the 31 individuals found to be G6PDd by sequencing, 29% (9) hemizygous males, 16.13% (5) homozygous females and 54.84% (17) heterozygous females were found for 376A+ mutation. The highest asymptomatic malaria infection detected with RDT was P. falciparum. Conclusion: - This study found high Genetic diversity (14%) across the G6PD gene in the study population. As the use of currently available radical cures (gametocidal drugs) against plasmodium are known to induce hemolytic anemia, further studies in larger groups needs to be done. In this study the limited number (222/1609) of samples sequenced from all study sites resulted in higher number of G6PDd individuals. . Keywords: - G6PD, G6PDd, Haemolytic anaemia, DNA sequencing, Haplotype, Gene mutation, Malaria, Ethiopia.
  • No Thumbnail Available
    Item
    Species delimitation in the genus Aloe has proved complicated due to interlocked morphologies. This study investigated the taxonomic relationships of Aloe macrocmpa Todaro and A. lateritia Engler using both morphological and molecular teclmiques. The morphological results indicated that the natme of variation in the populations of the two taxa is continuous. Microscopic studies of pollen grains and the leaf cuticle showed little differentiation among populations of the two taxa. The low genetic distances «0.3) between the populations studied are in support of the hypothesis that the populations may be conspecific, suggesting infraspecific rauk(s) for the taxa.
    (Addis Ababa University, 2005-05) Gadisa Endalamaw; Aseffa Abraham (PhD); Gedamu Lashitew (Professor); Dagne Kifle (PhD)
    The various species of Leishmania cannot be distinguished morphologically, but the treatment of leishmaniasis depends on the specific causative species. Thus accurate and rapid diagnosis of the specific species of Leishmania should be available for effective treatment of patients. Identification of Leishmania species in humans, in insect vectors and reservoir hosts should be available before planning for large-scale epidemiological survey, control programs and possible vaccine and/or drug trials. Therefore, the aim of this work was to establish isoenzyme technique at AHRI as a gold standard for species identification and introduce PCR-methods for species-specific diagnosis of leishmaniasis directly from clinical materials. In this line, cultured parasites from 55 localized cutaneous leishmaniasis (LCL) and 3 diffused cutaneous leishmaniasis (DCL) cases), diagnosed at the All Africa Leprosy and Tuberculosis Research, Rehabilitation and Training Center (ALERT) and from Ochollo village were analyzed. Species typing with isoenzyme electrophoresis and PCR-based techniques showed that, in all the cases, L. aethiopica is the aetiologic agent. Moreover, there was no strain difference between those causing LCL and DCL. The comparison of the isoenzyme and the PCRbased species typing techniques confirmed that the intergenic transcribed spacer-1 polymerase chain reaction-restriction fragment length polymorphism technique alone could be used for species typing. The sensitivity and specificity of the technique shows its potential for species specific diagnosis of leishmaniasis from clinical samples avoiding the need for culture. Thus, effective species-specific treatment of patients, which is a requirement in leishmaniasis, could be effected in a timely manner. Key words: Leishmania aethiopica, Isoenzyme, ITS1-PCR-RFLP, ALERT, Ochollo