Distribution of Biomphalaria Snails in Associated Vegetations and Schistosome Infection Prevalence Along the Shores of Lake Victoria in Mbita, Kenya: A Cross-Sectional Study

Background: Schistosomiasis due to Schistosoma mansoni remains a major public health problem and cause of morbidity and mortality in sub-Saharan Africa despite the implementation of control programmes. More than 6 million Kenyans are at risk of infection. Regarding control measures, Biomphalaria snail species, which are the obligatory intermediate hosts for transmission of S. mansoni, have been neglected. Mbita subcounty in Homa Bay County, western Kenya, along Lake Victoria basin, has a high prevalence of S. mansoni infection despite mass drug administration. This study aimed to determine the abundance of Biomphalaria, with their associated vegetation and schistosome infection rates, along Mbita shoreline.   Methods: Sixteen purposively selected sites along the Mbita shoreline were sampled for Biomphalaria snails using a 30-minute scooping technique. Global positioning system technology was used to map selected sites. The associated vegetation at sampling sites were collected and identified. Schistosome infection status among the snails was determined via the detection of cercaria shedding.   Results: A total of 3,135 Biomphalaria sudanica snails were collected. The number of snails collected differed significantly between the 16 sites (F=11.735; degrees of freedom [df]=15.836; P<.001). Significant mean differences (MD) were also observed in terms of the number of snails collected per vegetation type (F=7.899; df=5.846; P<.001). The mean number of snails collected from Cyprus gracilis was significantly higher than that from Enydra fluactuants (MD= 2.03; P<.001), Eichhornia crassipes (MD=4.15; P<.010), and E. fluactuants mixed with E. crassipes (MD=2.516; P<.010). A total of 21 (0.67%) snails shed human cercariae, while 27 (0.86%) snails shed nonhuman cercariae, despite 14 sites having human faeces contamination.   Conclusion: Although the schistosome infection prevalence among the snails was low, these sites may still be important exposure sites. C. gracilis is the main vegetation type associated with a high abundance of Biomphalaria snails. Molecular techniques are necessary for verification of schistosome positivity among the snails

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

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

The Levels of CD16/Fcγ Receptor IIIA on CD14+ CD16+ Monocytes Are Higher in Children with Severe Plasmodium falciparum Anemia than in Children with Cerebral or Uncomplicated Malaria▿

Fc gamma receptor IIIA (CD16/FcγRIIIA) on monocytes/macrophages may play an important role in the pathogenesis of severe malarial anemia (SMA) by promoting phagocytosis of IgG-coated uninfected red cells and by allowing the production of tumor necrosis factor alpha (TNF-α) upon cross-linking by immune complexes (ICs). However, not much is known about the differential expression of this receptor on monocytes of children with severe malaria and uncomplicated malaria. Therefore, we investigated the expression of CD16/FcγRIIIA on monocytes of children with SMA, cerebral malaria (CM), and their age-matched uncomplicated malaria controls by flow cytometry. Since CD14low (CD14+) monocytes are considered more mature and macrophage-like than CD14high (CD14++) monocytes, we also compared the level of expression of CD16/FcγRIIIA according to the CD14 level and studied the relationship between CD16/FcγRIIIA expression and intracellular TNF-α production upon stimulation by ICs. CD16/FcγRIIIA expression was the highest overall on CD14+ CD16+ monocytes of children with SMA at enrollment. At convalescence, SMA children were the only ones to show a significant decline in the same parameter. In contrast, there were no significant differences among groups in the expression of CD16/FcγRIIIA on CD14++ CD16+ monocytes. A greater percentage of CD14+ CD16+ monocytes produced TNF-α upon stimulation than any other monocyte subset, and the amount of intracellular TNF-α correlated positively with CD16/FcγRIIIA expression. Furthermore, there was an inverse correlation between hemoglobin levels and CD16/FcγRIIIA expression in children with SMA and their controls. These data suggest that monocytes of children with SMA respond differently to Plasmodium falciparum infection by overexpressing CD16/FcγRIIIA as they mature, which could enhance erythrophagocytosis and TNF-α production

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

MOESM2 of Seroprevalence and determinants of transfusion transmissible infections among voluntary blood donors in Homabay, Kisumu and Siaya counties in western Kenya

Additional file 2. Pre-donation questionnaire

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