Plasmodium gametocyte carriage in humans and sporozoite rate in anopheline mosquitoes in Gondar zuria district, Northwest Ethiopia.

Although the overall burden of malaria is decreasing in Ethiopia, a recent report of an unpredictable increased incidence may be related to the presence of community-wide gametocyte-carrier individuals and a high proportion of infected vectors. This study aimed to reveal the current prevalence of gametocyte-carriage and the sporozoite infectivity rate of Anopheles vectors for Plasmodium parasites. A community-based cross-sectional study was conducted from May 01 to June 30/2019. A total of 53 households were selected using systematic random sampling and a 242 study participants were recruited. Additionally,515 adult female Anopheles mosquitoes were collected using Center for Diseases Control and Prevention (CDC) light traps and mouth aspirators. Parasite gametocytemia was determined using giemsa stain microscopy, while sporozoite infection was determined by giemsa staining microscopy and enzyme linked immunosorbent assay (ELISA). Among the total 242 study participants, 5.4% (95%, CI = 2.9-8.3) of them were positive for any of the Plasmodium species gametocyte. Furthermore, being female [AOR = 15.5(95%, CI = 1.71-140.39)], age group between 15-29 years old [AOR = 16.914 (95%, CI = 1.781-160.63)], no ITNs utilization [AOR = 16.7(95%, CI = 1.902 -146.727)], and high asexual parasite density [(95%, CI = 0.057-0.176, P = 0.001, F = 18.402)] were identified as statistically significant factors for gametocyte carriage. Whereas sporozoite infection rate was 11.6% (95%, CI = 8.2-15.5) and 12.7% (95%, CI = 9.6-16.3) by microscopy and ELISA, respectively. Overall, this study indicated that malaria remains to be an important public health problem in Gondar Zuria district where high gametocyte carriage rate and sporozoite infection rate could sustain its transmission and burden. Therefore, in Ethiopia, where malaria elimination program is underway, frequent, and active community-based surveillance of gametocytemia and sporozoite infection rate is important.

Ultrasensitive loop mediated isothermal amplification (US-LAMP) to detect malaria for elimination.

BACKGROUND: Malaria elimination requires diagnostic methods able to detect parasite levels well below what is currently possible with microscopy and rapid diagnostic tests. This is particularly true in surveillance of malaria at the population level that includes so-called "asymptomatic" individuals. METHODS: The development of the first ultrasensitive loop mediated amplification method capable of detecting malaria from both whole blood and dried blood spots (DBS) is described. The 18S rRNA and corresponding genes that remain stable on DBS for up to 5 months are targeted. RESULTS: In the case of Plasmodium falciparum, lower limits of detection of 25 parasite/mL and 50-100 parasite/mL from whole blood and DBS were obtained, respectively. A sensitivity of 97.0% (95% CI 82.5-99.8) and specificity of 99.1% (95% CI 97.6-99.7) was obtained for the detection of all species in asymptomatic individuals from Africa and Asia (n = 494). CONCLUSION: This tool is ideally suited for low middle-income countries where malaria is endemic and ultrasensitive surveillance of malaria is highly desirable for elimination.

Single-Dose Tafenoquine to Prevent Relapse of Plasmodium vivax Malaria.

BACKGROUND: Treatment of Plasmodium vivax malaria requires the clearing of asexual parasites, but relapse can be prevented only if dormant hypnozoites are cleared from the liver (a treatment termed "radical cure"). Tafenoquine is a single-dose 8-aminoquinoline that has recently been registered for the radical cure of P. vivax. METHODS: This multicenter, double-blind, double-dummy, parallel group, randomized, placebo-controlled trial was conducted in Ethiopia, Peru, Brazil, Cambodia, Thailand, and the Philippines. We enrolled 522 patients with microscopically confirmed P. vivax infection (>100 to <100,000 parasites per microliter) and normal glucose-6-phosphate dehydrogenase (G6PD) activity (with normal activity defined as ≥70% of the median value determined at each trial site among 36 healthy male volunteers who were otherwise not involved in the trial). All patients received a 3-day course of chloroquine (total dose of 1500 mg). In addition, patients were assigned to receive a single 300-mg dose of tafenoquine on day 1 or 2 (260 patients), placebo (133 patients), or a 15-mg dose of primaquine once daily for 14 days (129 patients). The primary outcome was the Kaplan-Meier estimated percentage of patients who were free from recurrence at 6 months, defined as P. vivax clearance without recurrent parasitemia. RESULTS: In the intention-to-treat population, the percentage of patients who were free from recurrence at 6 months was 62.4% in the tafenoquine group (95% confidence interval [CI], 54.9 to 69.0), 27.7% in the placebo group (95% CI, 19.6 to 36.6), and 69.6% in the primaquine group (95% CI, 60.2 to 77.1). The hazard ratio for the risk of recurrence was 0.30 (95% CI, 0.22 to 0.40) with tafenoquine as compared with placebo (P<0.001) and 0.26 (95% CI, 0.18 to 0.39) with primaquine as compared with placebo (P<0.001). Tafenoquine was associated with asymptomatic declines in hemoglobin levels, which resolved without intervention. CONCLUSIONS: Single-dose tafenoquine resulted in a significantly lower risk of P. vivax recurrence than placebo in patients with phenotypically normal G6PD activity. (Funded by GlaxoSmithKline and Medicines for Malaria Venture; DETECTIVE ClinicalTrials.gov number, NCT01376167 .).

Molecular detection of Enteropathogens from diarrheic stool of HIV positive patients in Gondar, Ethiopia.

BACKGROUND: Infectious diarrhea is a common problem in the developing world, especially among people living with HIV/AIDS. Traditional diagnostic methods such as stool culture and microscopic examination are limited by resources and poor sensitivity. The use of molecular diagnostics for enteropathogen detection in this region of sub-Saharan Africa has not been fully explored. We sought to identify risk factors and characterize enteropathogens from diarrheic stools of HIV-positive patients in Gondar, Ethiopia using multiplex molecular panels targeting key infectious agents. METHODS: A cross-sectional study of 100 stool samples was performed. Samples were collected consecutively from HIV- positive patients presenting with diarrhea at University of Gondar Hospital clinic, a major center in NW Ethiopia. Genomic DNA was extracted from stool and processed using a multiplex molecular panel Allplex™ [Seegene, Canada]. Correlations between patient characteristics, symptoms, public health risk factors, and enteropathogen type (s) were studied. Eighty-six samples were successfully analyzed by molecular methods. RESULTS: The mean age was 35 with 43% male. Eighty percent lived in an urban area, 18% had access to well water only, and 81% practiced proper hand hygiene. The majority of patients (72%) were receiving HAART with a median CD4 cell count of 362/µL. Multiple pathogens were detected in 94% of specimens, with an average of 5 enteropathogens per sample. Common bacteria, viruses, and parasites detected were Shigella spp./enteroinvasive E. coli (80%), enterotoxigenic E. coli (73%), Norovirus (16%) and B. hominis (62%). CD4 cell count < 500/ µL was associated with the presence of viruses (p = 0.004) and the absence of STEC (p = 0.010). The use of HAART or CD4 levels was not associated with the number of enteropathogens detected. CONCLUSIONS: Diarrheic stool from HIV-positive outpatients in Gondar, Ethiopia had on average 5 enteropathogens present in their stool. Shigellaspp./enteroinvasive E. coli and enterotoxigenic E. coli are the major pathogens, not dissimilar to immunocompetent individuals in low income countries.

Visceral Leishmaniasis-Malaria Coinfection and Their Associated Factors in Patients Attending Metema Hospital, Northwest Ethiopia: Suggestion for Integrated Vector Management.

BACKGROUND: Despite high prevalence of visceral leishmaniasis and malaria in the study area, their coinfection remains unknown. Therefore, this study was aimed to document VL-malaria coinfections and their associated factors. METHODS: A cross-sectional study was conducted among clinical suspected VL patients attending Metema hospital, Northwest Ethiopia, from January 2014 to June 2014. Blood sample was tested by rk39 antigen-based DiaMed IT-Leish dipstick and Giemsa stain microscopic examination of thick and thin blood smears for malaria detection was performed. RESULT: A total of 384 VL suspected patients were included in the study. Out of these, the prevalence of VL was 83 (21.6%) while the prevalence of malaria was 45 (11.7%). Of malaria cases, 40 (89%) were positive for P. falciparum and 5 (11%) positive for P. vivax. The overall prevalence of VL-malaria coinfection was 16 (4.2%). One-hundred eighty (46.9%) study participants have history of travel. Of these, 10 (5.6%) have VL-malaria coinfections. Age less than 5 years was associated with VL-malaria coinfection. CONCLUSION: This study highlights the importance of performing malaria screening amongst VL patients living in malaria-endemic areas, particularly in patients under five years.

Vitamin D deficiency among newly diagnosed tuberculosis patients and their household contacts: a comparative cross-sectional study.

BACKGROUND: Recent studies suggest that the incidence and severity of tuberculosis is associated with low levels of vitamin D. Even though individuals living in Ethiopia have a high exposure to sunlight which is a source of vitamin D, tuberculosis is still one of the major causes of morbidity and mortality in the country. Therefore, this study aimed to determine the prevalence and associated factors of vitamin D deficiency in newly diagnosed tuberculosis patients, household contacts and community controls in Gondar, Ethiopia. METHODS: A comparative cross-sectional study design was conducted. Blood samples were collected from newly diagnosed smear positive pulmonary TB patients, their household contacts and community controls. Serum 25(OH)-vitamin D3 was determined by an Enzyme Linked Immunosorbent Assay. A serum level of 25(OH)-vitamin D3 below < 50 nmol/L was defined as vitamin D deficiency and <25 nmol/L as severe vitamin D deficiency. RESULTS: A total of 126 newly diagnosed smear positive TB patients, 57 house hold contacts and 70 apparently community controls were included in the study. The mean ± SD age (years) of TB patients, house hold contacts and community controls was 29.8 ± 11.9, 24.3 ± 14.7 and 27.3 ± 7.6 respectively. Ninety out of 126 (71.4%) TB patients were underweight with a BMI of < 18.5 kg/m2. The mean 25(OH)-vitamin D3 level of TB patients (30.1 ± 19.3 nmol/L) was significantly lower than community controls (38.5 ± 20.9 nmol/L, P = 0.005 and household contacts (37.7 ± 12.8 nmol/L, P =0.031).). The prevalence of vitamin D deficiency was higher in TB patients (83.3%) than in community controls (67.1%, P = 0.009). The prevalence of vitamin D deficiency was also found higher in household contacts (80.7%). Severe vitamin D deficiency was observed in 53%(67/126), 30% (21/70), 19.3%(11/57) of TB patients, community controls and household contacts respectively. Low BMI (AOR = 2.13; 95%CI: 1.02, 3.28) and being positive for tuberculosis (AOR = 1.93; 95%CI: 1.06, 2.86) were significant predictors of severe vitamin D deficiency. CONCLUSION: High prevalence of vitamin D deficiency was found among newly diagnosed TB patients and in their household contacts. The present study warrants further studies to determine the role of vitamin D supplementation in the prevention and treatment of tuberculosis in Ethiopia.

Performance of loop-mediated isothermal amplification (LAMP) for the diagnosis of malaria among malaria suspected pregnant women in Northwest Ethiopia.

BACKGROUND: Malaria is a major public health problem and an important cause of maternal and infant morbidity in sub-Saharan Africa, including Ethiopia. Early and accurate diagnosis of malaria with effective treatment is the best strategy for prevention and control of complications during pregnancy and infant morbidity and mortality. However, laboratory diagnosis has relied on the identification of malaria parasites and parasite antigens in peripheral blood using Giemsa-stained microscopy or rapid diagnostic tests (RDTs) which lack analytical and clinical sensitivity. The aim of this study was to evaluate the performance of loop-mediated isothermal amplification (LAMP) for the diagnosis of malaria among malaria suspected pregnant women in Northwest Ethiopia. METHODS: A cross sectional study was conducted from January to April 2016. Pregnant women (n = 87) suspected of having malaria at six health centres were enrolled. A venous blood sample was collected from each study subject, and analysed for Plasmodium parasites by microscopy, RDT, and LAMP. Diagnostic accuracy outcome measures (sensitivity, specificity, predictive values, and Kappa scores) of microscopy, RDT and LAMP were compared to nested polymerase chain reaction (nPCR) as the gold standard. Specimen processing and reporting times were documented. RESULTS: Using nPCR as the gold standard technique, the sensitivity of microscopy and RDT was 90 and 70%, and the specificity was 98.7 and 97.4%, respectively. LAMP assay was 100% sensitive and 93.5% specific compared to nPCR. CONCLUSIONS: This study showed higher sensitivity of LAMP compared to microscopy and RDT for the detection of malaria in pregnancy. Increased sensitivity and ease of use with LAMP in point-of-care testing for malaria in pregnancy was noted. LAMP warrants further evaluation in intermittent screening and treatment programmes in pregnancy.

A Unique Plasmodium falciparum K13 Gene Mutation in Northwest Ethiopia.

Artemisinin combination therapy (ACT) is the first line to treat uncomplicated Plasmodium falciparum malaria worldwide. Artemisinin treatment failures are on the rise in southeast Asia. Delayed parasite clearance after ACT is associated with mutations of the P. falciparum kelch 13 gene. Patients (N = 148) in five districts of northwest Ethiopia were enrolled in a 28-day ACT trial. We identified a unique kelch 13 mutation (R622I) in 3/125 (2.4%) samples. The three isolates with R622I were from Negade-Bahir and Aykel districts close to the Ethiopia-Sudan border. One of three patients with the mutant strain was parasitemic at day 3; however, all patients cleared parasites by day 28. Correlation between kelch 13 mutations and parasite clearance was not possible due to the low frequency of mutations in this study.

Prevalence and clinical correlates of Schistosoma mansoni co-infection among malaria infected patients, Northwest Ethiopia.

BACKGROUND: In Ethiopia, where malaria and schistosomiasis are co-endemic, co-infections are expected to be high. However, data about the prevalence of malaria-schistosomiasis co-infection and their clinical correlation is lacking. Therefore, the aim of this study was to assess prevalence of Schistosoma mansoni co-infection and associated clinical correlates in malaria patients. METHODS: A cross-sectional study was conducted in 2013 at Chwahit Health Center, in northwest Ethiopia. Blood film positive malaria patients (N = 205) were recruited for the study. Clinical, parasitological, hematological, and biochemical parameters were assessed from every study participant. Stool samples were also collected and processed with Kato-Katz technique to diagnose and classify intensity of Schistosoma mansoni. RESULTS: The prevalence of Schistosoma mansoni and malaria co-infection was 19.5%. The age group of 16-20 years old was significantly associated with co-infection. Co-infected patients with a moderate-heavy egg burden of Schistosoma mansoni had significantly high mean Plasmodium parasitemia. On the other hand, age group of 6-10 years old and moderate-heavy Schistosoma mansoni co-infection were significantly associated with severe malaria. CONCLUSIONS: Prevalence of malaria and Schistosoma mansoni co-infection in the study area was considerably high. Severity of malaria and parasitemia of Plasmodium were associated with certain age groups and intensity of concurrent Schistosoma mansoni. Further study is needed to explore the underlying mechanisms of interaction between malaria and Schistosoma mansoni.

Diagnostic performance of rapid diagnostic tests for the diagnosis of malaria at public health facilities in north-west Ethiopia.

OBJECTIVE: To assess the performance of RDTs against nested polymerase chain reaction (nPCR) for the diagnosis of malaria in public health facilities in north-western Ethiopia. METHODS: Cross-sectional study at public health facilities in North Gondar, Ethiopia, of 359 febrile patients with signs and symptoms consistent with malaria. Finger prick blood samples were collected for testing in a P. falciparum/pan-malaria RDTs and for molecular analysis. Sensitivity, specificity and predictive values were determined for the RDTs using nPCR as reference diagnostic method. Kappa value was determined to demonstrate the consistency of the results between the diagnostic tools. RESULTS: By RDTs, 22.28% (80/359) of patients tested positive for malaria, and by nPCR, 27.02% (97/359) did. In nPCR, 1.67% (6/359) and 0.28% (1/359) samples were positive for P. ovale and P. malariae, which had almost all tested negative in the RDTs. The sensitivity, specificity, positive and negative predictive values of RDTs for the diagnosis of malaria were 62.9%, 92.7%, 76.3% and 87.1%, respectively, with 0.589 measurement agreement between RDTs and nPCR. The sensitivity and specificity of RDTs for P. falciparum identification only were 70.8% and 95.2%, and 65.2% and 93.1% for P. vivax. CONCLUSION: Although RDTs are commonly used at health posts in resource-limited environments, their sensitivity and specificity for the detection and species identification of Plasmodium parasites were poor compared to nPCR, suggesting caution in interpreting RDTs results. Particularly, in the light of expanded efforts to eliminate malaria in the country, more sensitive diagnostic procedures will be needed.

Therapeutic efficacy of artemether-lumefantrine for the treatment of uncomplicated Plasmodium falciparum malaria in Enfranze, north-west Ethiopia.

BACKGROUND: Plasmodium falciparum accounts for approximately 60% of malaria cases in Ethiopia and artemether-lumefantrine has been used as a first-line treatment for uncomplicated P. falciparum malaria since 2004. The aim of this study was to assess the therapeutic efficacy of artemether-lumefantrine (AL) for the treatment of uncomplicated P. falciparum malaria in north-western Ethiopia. METHODS: A 28-day one-arm, prospective evaluation of the clinical and parasitological response to the first-line treatment for uncomplicated P. falciparum malaria was conducted in Enfranze Health Centre in accordance with the 2009 WHO efficacy study guidelines. Patients were treated with a 3-day course of AL and clinical and parasitological parameters were monitored over a 28-day follow-up. All data from recruited patients were imported into an electronic data base and Kaplan-Meier survival analysis was used for analysing primary [early treatment failures (ETF), late clinical failure (LCF), late parasitological failures (LPF), and adequate clinical and parasitological response (ACPR)] and secondary (PCT, GCT and FCT) outcomes. RESULTS: Eighty patients were enrolled and all of them completed the 28-day follow-up period. The PCR-corrected cure rate was 95.0% (95% CI 87.0-98.4%) and there were two ETF, one LCF and three LPF. Two of the LPF were classified as re infections by PCR. Seventy three point seven five percent, 91.25 and 95% of patients had cleared their parasitaemia by days 1, 2, and 3, respectively, and 75, 91.25 and 96.25% of patients had cleared their fever by days 1, 2, and 3. All patients completely cleared their gametocytes by day 7. CONCLUSION: The relatively high cure rate, low proportion of patients still positive on day 3 as well as parasite clearance times in this study would indicate no imminent threat of artemisinin resistance development in the region. However, the threat of spreading or de novo development of artemisinin resistance warrants regular monitoring of drug efficacy throughout the region.

Prevalence of urinary schistosomiasis and associated risk factors among Abobo Primary School children in Gambella Regional State, southwestern Ethiopia: a cross sectional study.

BACKGROUND: In Ethiopia, urinary schistosomiasis caused by Schistosoma haematobium has been known to be endemic in several lowland areas of the country where it causes considerable public health problems, mainly among school-age children. However, information on recent magnitude and risk factors of the disease is lacking, particularly for Gambella area. Therefore, this study aimed to assess the prevalence of urinary schistosomiasis and associated risk factors among Abobo Primary School children in Gambella, southwestern Ethiopia. METHODS: A cross-sectional study involving 304 school children was conducted in Abobo Primary School, Gambella Regional State, southwestern Ethiopia, from February to June 2014. Ten ml of urine sample was collected from each study participant and processed for microscopic examination by the urine filtration method; egg load for positive individuals was determined per 10 ml of urine. Data on socio-demographic characteristics and risk factors were collected using an interview-based questionnaire. The data were entered into and analyzed with SPSS version 20. Logistic regression and odds ratio were used to measure association and strength between variables, respectively. P-value < 0.05 at 95% CI was considered as statistically significant. RESULTS: The prevalence of urinary schistosomiasis was 35.9% (109/ 304) with a mean egg intensity of 8.76 per 10 ml of urine. Being male [AOR (95%CI) = 2.15(1.31, 3.52)], having father as a farmer [AOR (95%CI) = 1.96(1.19, 3.22)] and children living apart from parents [AOR (95% CI): 3.09 (1.14, 8.4)] were significantly associated with urinary schistosomiasis. CONCLUSION: The present study area in Gambella Regional State, southwestern Ethiopia, represents moderate-risk community for urinary schistosomiasis. Sex, father's occupation and living apart from parents were found to be associated with infection. Treatment of all school-age children and fishermen is required once every 2 years until the prevalence of infection falls below the level of public health importance. It is also recommended to complement praziquantel treatment with supplementary measures such as provision of sanitation facilities and health education.

Evaluation of non-instrumented nucleic acid amplification by loop-mediated isothermal amplification (NINA-LAMP) for the diagnosis of malaria in Northwest Ethiopia.

BACKGROUND: Malaria is a major public health problem in sub-Saharan African countries including Ethiopia. Early and accurate diagnosis followed by prompt and effective treatment is among the various tools available for prevention, control and elimination of malaria. This study aimed to evaluate the performance of non-instrumented nucleic acid amplification loop-mediated isothermal amplification (NINA-LAMP) compared to standard thick and thin film microscopy and nested PCR as gold standard for the sensitive diagnosis of malaria in Northwest Ethiopia. METHODS: A cross-sectional study was conducted in North Gondar, Ethiopia from March to July 2014. Eighty-two blood samples were collected from malaria suspected patients visiting Kola Diba Health Centre and analysed for Plasmodium parasites by microscopy, NINA-LAMP and nested PCR. The NINA-LAMP method was performed using the Loopamp Malaria Pan/Pf detection kits for detecting DNA of the genus Plasmodium and more specifically Plasmodium falciparum using an electricity-free heater. Diagnostic accuracy outcome measures (analytical sensitivity, specificity, predictive values, and Kappa scores) of NINA-LAMP and microscopy were compared to nested PCR. RESULTS: A total of 82 samples were tested in the primary analysis. Using nested PCR as reference, the sensitivity and specificity of the primary NINA-LAMP assay were 96.8% (95% confidence interval (CI), 83.2% - 99.5%) and 84.3% (95% CI, 71.4% - 92.9%), respectively for detection of Plasmodium genus, and 100% (95% CI, 75.1% - 100%) and 81.2% (95% CI, 69.9% - 89.6%), respectively for detection of P. falciparum parasite. Microscopy demonstrated sensitivity and specificity of 93.6% (95% CI, 78.5% - 99.0%) and 98.0% (95% CI, 89.5% - 99.7%), respectively for the detection of Plasmodium parasites. Post-hoc repeat NINA-LAMP analysis showed improvement in diagnostic accuracy, which was comparable to nested PCR performance and superior to microscopy for detection at both the Plasmodium genus level and P. falciparum parasites. CONCLUSION: NINA-LAMP is highly sensitive for the diagnosis of malaria and detection of Plasmodium parasite infection at both the genus and species level when compared to nested PCR. NINA-LAMP is more sensitive than microscopy for the detection of P. falciparum and differentiation from non-falciparum species and may be a critical diagnostic modality in efforts to eradicate malaria from areas of low endemicity.

Comparison of Giemsa microscopy with nested PCR for the diagnosis of malaria in North Gondar, north-west Ethiopia.

BACKGROUND: Malaria remains one of the leading communicable diseases in Ethiopia. Early diagnosis combined with prompt treatment is one of the main strategies for malaria prevention and control. Despite its limitation, Giemsa microscopy is still considered to be the gold standard for malaria diagnosis. This study aimed to compare the performance of Giemsa microscopy with nested polymerase chain reaction (nPCR) for the diagnosis of malaria in north-west Ethiopia. METHODS: A cross sectional study was conducted in public health facilities in North Gondar, from March 2013 to April 2013. A total number of 297 subjects with suspected malaria were enrolled in the study. Finger-prick blood samples were collected and examined for Plasmodium parasites using Giemsa microscopy and standard nPCR. RESULTS: Among the study participants, 61.6% (183/297) patients tested positive for malaria by Giemsa microscopy of which, 72.1% (132/183) and 27.9% (51/183) were diagnosed as Plasmodium falciparum and Plasmodium vivax, respectively. By nPCR, 73.1% (217/297) were malaria-positive. Among microscopy-negative samples, 13.1% (39/297) samples turned malaria-positive in nPCR. In nPCR, the rate of mixed Plasmodium infections was 4.7% (14/297) and 3.03% (9/297) were positive for Plasmodium ovale. Using nPCR as reference the sensitivity, specificity, positive predictive and negative predictive values of Giemsa microscopy were 82.0%, 93.8%, 97.3% and 65.8%, respectively, with a good agreement (κ = 0.668) to nested PCR. The sensitivity and specificity of Giemsa microscopy in identifyingP. falciparium infections were 74.0% and 87.4% and 63.2% and 96.5% for P. vivax infections, respectively. CONCLUSION: Although Giemsa microscopy remains the gold standard for malaria diagnosis in resource-limited environments, its sensitivity and specificity as compared to nPCR is limited suggesting exploration of novel rapid and simplified molecular techniques for malaria-endemic countries. A high rate of misclassification and misidentification highlights the importance of adequate training for staff involved in malaria diagnosis.

Asymptomatic Malaria and Associated Risk Factors among School Children in Sanja Town, Northwest Ethiopia.

Introduction. Asymptomatic malaria is prevalent in highly endemic areas of Africa and is new challenge for malaria prevention and control strategies. Objective. To determine the prevalence of asymptomatic malaria and associated risk factors among school children in Sanja Town, northwest Ethiopia. Methods. A cross-sectional study was conducted from February to March 2013, on 385 school children selected using stratified proportionate systematic sampling technique. Pretested questionnaire was used to collect sociodemographic data and associated risk factors. Giemsa-stained thin and thick blood films were examined for detection, identification, and quantification of malaria parasites. Data were entered and analyzed using SPSS 20.0 statistical software. Multivariate logistic regression was done for assessing associated risk factors and proportions for categorical variables were compared using chi-square test. P values less than 0.05 were taken as statistically significant. Results. The prevalence of asymptomatic malaria was 6.8% (n = 26). The majority of parasitemic study participants had low parasite density 65.5% (17/26). Level of grade, age, bed net usage, and frequent exposure to malaria infection were associated with risk of asymptomatic malaria. Conclusion. Asymptomatic malaria was low in this study area and is associated with level of grade, age, bed net usage, and frequent exposure to malaria infection.