Comparison of Microscopy and PCR for Detection of Giardia Lamblia and Entamoeba Histolytica in Human Stool Specimens in a Resource Limited Setting in Western Kenya

BACKGROUND፡ Accurate diagnosis of Giardia lamblia and Entamoeba histolytica is important since these intestinal parasites account for a significant proportion of morbidity and mortality globally. Microscopy is the key diagnostic test used for diagnosis of the two parasites. Other tests including rapid diagnostic tests and polymerase chain reaction have been developed to improve the detection of these parasites. Most of these newer tests are not affordable in resource limited settings, hence the over reliance on microscopy. The objective of this study was to determine the reliability of microscopy in a resource limited setting in Western Kenya, a region endemic for the two intestinal parasites.METHODS: Polymerase chain reaction, the gold standard test, was performed on stool samples suspected for G. lamblia and E. histolytica. Microscopy was then performed on the same samples and the two tests compared.RESULTS: Microscopy was found to be 64.4% sensitive, 86.6% specific for the detection of G. lamblia. Additionally, this test was 64.2% sensitive and 83.6% specific for the diagnosis of E. histolytica. Cohen’s kappa values of 0.51 and 0.47 were determined for microscopy for G. lamblia and E. histolytica respectively. McNemar’s test revealed a significant difference between the two tests, P<0.001.CONCLUSION: This study found microscopy to be a reliable diagnostic test in this resource limited setting

Genomic surveillance of SARS-COV-2 reveals diverse circulating variant lineages in Nairobi and Kiambu Counties, Kenya

Genomic surveillance and identification of COVID-19 outbreaks are important in understanding the genetic diversity, phylogeny, and lineages of SARS-CoV-2. Genomic surveillance provides insights into circulating infections, and the robustness and design of vaccines and other infection control approaches. We sequenced 57 SARS-CoV-2 isolates from a Kenyan clinical population, of which 55 passed quality checks using the Ultrafast Sample placement on the Existing tRee (UShER) workflow. Phylo-genome-temporal analyses across two regions in Kenya (Nairobi and Kiambu County) revealed that B.1.1.7 (Alpha; n = 32, 56.1%) and B.1 (n = 9, 15.8%) were the predominant lineages, exhibiting low Ct values (5-31) suggesting high infectivity, and variant mutations across the two regions. Lineages B.1.617.2, B.1.1, A.23.1, A.2.5.1, B.1.596, A, and B.1.405 were also detected across sampling sites within target populations. The lineages and genetic isolates were traced back to China (A), Costa Rica (A.2.5.1), Europe (B.1, B.1.1, A.23.1), the USA (B.1.405, B.1.596), South Africa (B.1.617.2), and the United Kingdom (B.1.1.7), indicating multiple introduction events. This study represents one of the genomic SARS-CoV-2 epidemiology studies in the Nairobi metropolitan area, and describes the importance of continued surveillance for pandemic control

Correction to: Seroprevalence and determinants of transfusion transmissible infections among voluntary blood donors in Homabay, Kisumu and Siaya counties in western Kenya

Following publication of the original article [1], the authors reported that for two of the authors, Felix Humwa and Vallarie Opollo, an incorrect affiliation has been given. In this Correction the incorrect and correct affiliations are listed

Schistosomiasis diagnosis: Challenges and opportunities for elimination.

OverviewThe roadmap adopted by the World Health Organization (WHO) for eliminating neglected tropical diseases aims to eliminate schistosomiasis, as a public health concern, by 2030. While progress has been made towards reducing schistosomiasis morbidity control in several sub-Saharan African countries, there is still more that needs to be done. Proper surveillance using accurate diagnostics with acceptable sensitivity and specificity is essential for evaluating the success of all efforts against schistosomiasis. Microscopy, despite its low sensitivity, remains the gold standard approach for diagnosing the disease. Although many efforts have been made to develop new diagnostics based on circulating parasite proteins, genetic markers, schistosome egg morphology, and their paramagnetic properties, none has been robust enough to replace microscopy. This review highlights common diagnostic approaches for detecting schistosomiasis in field and clinical settings, major challenges, and provides new and novel opportunities and diagnosis pathways that will be critical in supporting elimination of schistosomiasis.MethodsWe searched for relevant and reliable published literature from PubMed, Scopus, google scholar, and Web of science. The search strategies were primarily determined by subtopic, and hence the following words were used (schistosom*, diagnosis, Kato-Katz, antibody test, circulating antigen, POC-CCA, UCP-LF-CAA, molecular diagnostics, nucleic acid amplification test, microfluidics, lab-on a disk, lab-on chip, recombinase polymerase amplification (RPA), LAMP, portable sequencer, nanobody test, identical multi-repeat sequences, diagnostic TPPs, REASSURED, extraction free), and Boolean operators AND and/OR were used to refine the searching capacity. Due to the global public health nature of schistosomiasis, we also searched for reliable documents, reports, and research papers published by international health organizations, World Health Organization (WHO), and Center for Disease control and Elimination

Seroprevalence and determinants of transfusion transmissible infections among voluntary blood donors in Homabay, Kisumu and Siaya counties in western Kenya

Abstract Objective Since the implementation of a series of blood donation safety improvements in Kenya, information about seroprevalence and determinants of transfusion transmissible infections among voluntary blood donors especially in high HIV burden regions of Homabay, Kisumu and Siaya counties remain scanty. A cross-sectional study examining HIV, syphilis, hepatitis B and C virus sero-markers and associated determinants was conducted among voluntary blood donors. Their demographic characteristics and previous risk exposure were recorded in a pre-donation questionnaire, while blood samples collected were screened for hepatitis B, hepatitis C, human immunodeficiency viruses by ELISA and RPR (syphilis), then confirmed using CMIA. Results Overall TTIs seroprevalence was 114 (9.4%), distributed among HIV, HBV, HCV and syphilis at 14 (1.15%), 42 (3.46%), 39 (3.21%) and 19 (1.56%), respectively, with co-infections of 3 (0.25%). There were no significant differences in proportions distributions among demographic variables. However, high risk sex was significantly associated with higher odds of HBV infections [> 1 partner vs. 0–1 partner; odd ratio (OR) 2.60; 95% confidence interval (CI) 1.098–6.86; p = 0.046]. In conclusion, a substantial percentage of blood donors still harbor transfusion transmissible infections despite recent safety improvements with greater majority cases caused by HBV infections arising from previous exposure to high risk sex

Novel biomarkers with promising benefits for diagnosis of cervical neoplasia: a systematic review

Background; Cervical cancer screening is slowly transitioning from Pappanicolaou cytologic screening to primary Visual Inspection with Acetic Acid (VIA) or HPV testing as an effort to enhance early detection and treatment. However, an effective triage tests needed to decide who among the VIA or HPV positive women should receive further diagnostic evaluation to avoid unnecessary colposcopy referrals is still lacking. Evidence from experimental studies have shown potential usefulness of Squamous Cell Carcinoma Antigen (SCC Ag), Macrophage Colony Stimulating Factor (M-CSF), Vascular Endothelial Growth Factor (VEGF), MicroRNA, p16INKa / ki-67, HPV E6/E7/mRNA, and DNA methylation biomarkers in detecting premalignant cervical neoplasia. Given the variation in performance, and scanty review studies in this field, this systematic review described the diagnostic performance of some selected assays to detect high-grade cervical intraepithelial neoplasia (CIN2+) with histology as gold standard. Methods; We systematically searched articles published in English between 2012 and 2020 using key words from PubMed/Medline and SCOPUS with two reviewers assessing study eligibility, and risk of bias. We performed a descriptive presentation of the performance of each of the selected assays for the detection of CIN2 + . Results; Out of 298 citations retrieved, 58 articles were included. Participants with cervical histology yielded CIN2+ proportion range of 13.7–88.4%. The diagnostic performance of the assays to detect CIN2+ was; 1) SCC-Ag: range sensitivity of 78.6–81.2%, specificity 74–100%. 2) M-CSF: sensitivity of 68–87.7%, specificity 64.7–94% 3) VEGF: sensitivity of 56–83.5%, specificity 74.6–96%. 4) MicroRNA: sensitivity of 52.9–67.3%, specificity 76.4–94.4%. 5) p16INKa / ki-67: sensitivity of 50–100%, specificity 39–90.4%. 6) HPV E6/E7/mRNA: sensitivity of 65–100%, specificity 42.7–90.2%, and 7) DNA methylation: sensitivity of 59.7–92.9%, specificity 67–98%. Conclusion; Overall, the reported test performance and the receiving operating characteristics curves implies that implementation of p16ink4a/ki-67 assay as a triage for HPV positive women to be used at one visit with subsequent cryotherapy treatment is feasible. For the rest of assays, more robust clinical translation studies with larger consecutive cohorts of women participants is recommended

MOESM3 of Seroprevalence and determinants of transfusion transmissible infections among voluntary blood donors in Homabay, Kisumu and Siaya counties in western Kenya

Additional file 3. Excel dataset for regression analysis