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Development of cerebral malaria (CM) is driven by parasitemia levels, harmful inflammatory response, oxidative stress and consequent breach of the blood brain barrier. Use of adjunct therapy that utilizes an antioxidant and anti-inflammatory agent alongside chloroquine (CQ), may improve treatment outcome and shorten recovery from post-infection sequelae. Though withdrawn in some countries, CQ is still in use for prophylaxis and treatment of malaria in many countries. Current study investigated whether oral co-administration of 50 mg/kg CQ and 200 mg/kg of coenzyme Q(10) (CoQ(10)) would improve treatment outcome against experimental cerebral malaria (ECM) and assuage the deleterious effects of oxidative stress and inflammation upon infection by Plasmodium berghei ANKA (PbA) in a C57BL/6 J mouse model. Treatment with CQ + CoQ(10) resulted in an improved parasite elimination; clearing the parasite one day early, when compared to mice on CQ alone. Remarkably, treatment with CQ and CoQ(10) separately or in combination, assuaged PbA induced elevation of serum levels of TNF-α and IFN-γ an indication of protection from ECM progression. Furthermore, CQ and CoQ(10)-administration, blocked parasite-driven elevation of aspartate transaminase (AST), alanine transaminase (ALT) and bilirubin. In the presence of CQ and CoQ(10,) severe PbA-induced systemic induction of oxidative stress and resultant GSH depletion was reduced in the brain, liver, spleen, and kidney. Overall, these findings demonstrate that administration of CQ and CoQ(10) ameliorates harmful parasite-driven oxidative stress and inflammation, while slowing the progression to full blown ECM and may improve treatment outcome in CM.

Background Few studies have assessed the seroprevalence of antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among healthcare workers (HCWs) in Africa. We report findings from a survey among HCWs in 3 counties in Kenya. Methods We recruited 684 HCWs from Kilifi (rural), Busia (rural), and Nairobi (urban) counties. The serosurvey was conducted between 30 July and 4 December 2020. We tested for immunoglobulin G antibodies to SARS-CoV-2 spike protein, using enzyme-linked immunosorbent assay. Assay sensitivity and specificity were 92.7 (95% CI, 87.9-96.1) and 99.0% (95% CI, 98.1-99.5), respectively. We adjusted prevalence estimates, using bayesian modeling to account for assay performance. Results The crude overall seroprevalence was 19.7% (135 of 684). After adjustment for assay performance, seroprevalence was 20.8% (95% credible interval, 17.5%–24.4%). Seroprevalence varied significantly (P < .001) by site: 43.8% (95% credible interval, 35.8%–52.2%) in Nairobi, 12.6% (8.8%–17.1%) in Busia and 11.5% (7.2%–17.6%) in Kilifi. In a multivariable model controlling for age, sex, and site, professional cadre was not associated with differences in seroprevalence. Conclusion These initial data demonstrate a high seroprevalence of antibodies to SARS-CoV-2 among HCWs in Kenya. There was significant variation in seroprevalence by region, but not by cadre.

Hyperglycemia is the elevation of blood glucose concentrations above the normal range. Prolonged uncontrolled hyperglycemia is associated with serious life-threatening complications. Hyperglycemia arises from an imbalance between glucose production and glucose uptake and utilization by peripheral tissues. Disorders that compromise pancreatic function or affect the glucose counter-regulatory hormones cause hyperglycemia. Acute or serious illness or injury may also bring about hyperglycemia, as can many classes of drugs. Metformin lowers blood glucose levels by inhibiting the production of glucose by the liver whilst enhancing uptake of circulating glucose and its utilization in peripheral tissues such as muscle and adipose tissue. Metformin suppresses hepatic gluconeogenesis by inhibiting mitochondrial respiration and causing a reduction of cellular ATP levels. Metformin may also modulate the gut-brain-liver axis, resulting in suppression of hepatic glucose production. Metformin also opposes the hyperglycemic action of glucagon and may ameliorate pancreatic cell dysfunction associated with hyperglycemia. Metformin is therefore recommended for use in the prevention of hyperglycemia, including drug-induced hyperglycemia, in at risk patients. The benefits of metformin in the prevention of hyperglycemia are unmatched despite its contraindications.

BackgroundHIV and mental disorders are predicted to be the leading causes of illness worldwide by the year 2030. HIV-infected patients are at increased risk of developing mental disorders which are significantly associated with negative clinical outcomes and propagation of new HIV infections. There is little evidence that links inflammation to development of mental disorders among HIV patients. Therefore, the main objective of this study was to evaluate if mental health symptoms were associated with biomarkers of inflammation in HIV infected subjects.MethodsA cross-sectional study was conducted in Dar es Salam, Tanzania from March to May 2018. Standardized tools were used to collect data based on the World Health Organisation's (WHO) stepwise approach for non-communicable diseases (NCD) surveillance. A total of 407 HIV+ patients on antiretroviral therapy were recruited. The WHO stepwise approach for NCD surveillance was used to collect data together with anthropometric measurements. Mental health symptoms were determined based on self-reported thoughts of helplessness, suicide ideation, depression, despair, discouragement, and feelings of isolation. Enzyme-linked immunosorbent assay was used to test for inflammatory markers:- C-reactive protein (CRP), Iinterleukin-6 (IL-6), interleukin-18 (IL-18), soluble tumour necrosis factor receptor-I (sTNFR-I), and soluble tumour necrosis factor receptor-II (sTNFR-II). Bivariate and multi-variate analysis was conducted to examine the association between biomarkers and mental health symptoms.ResultsThe prevalence of self-reported mental health symptoms was 42% (n = 169). Participants with self-reported symptoms of mental health had elevated CRP, were less likely to walk or use a bicycle for at least 10 minutes, were less likely to participate in moderate-intensity sports or fitness activities, and had poor adherence to HIV treatment (p ConclusionHigh CRP and sTNFR II were important contributors to the prevalence of mental health symptoms. This study is among the minimal studies that have examined mental health issues in HIV, and therefore, the findings may offer significant knowledge despite the potential reverse causality. Regardless of the nature of these associations, efforts should be directed toward screening, referral, and follow-up of HIV patients who are at-risk for mental health disorders.

BackgroundFew studies have assessed the seroprevalence of antibodies against SARS-CoV-2 among Health Care Workers (HCWs) in Africa. We report findings from a survey among HCWs in three counties in Kenya.MethodsWe recruited 684 HCWs from Kilifi (rural), Busia (rural) and Nairobi (urban) counties. The serosurvey was conducted between 30th July 2020 and 4th December 2020. We tested for IgG antibodies to SARS-CoV-2 spike protein using ELISA. Assay sensitivity and specificity were 93% (95% CI 88-96%) and 99% (95% CI 98-99.5%), respectively. We adjusted prevalence estimates using Bayesian modeling to account for assay performance.ResultsCrude overall seroprevalence was 19.7% (135/684). After adjustment for assay performance seroprevalence was 20.8% (95% CI 17.5-24.4%). Seroprevalence varied significantly (pConclusionThese initial data demonstrate a high seroprevalence of antibodies to SARS-CoV-2 among HCWs in Kenya. There was significant variation in seroprevalence by region, but not by cadre.

The high proportion of SARS-CoV-2 infections that remain undetected presents a challenge to tracking the progress of the pandemic and implementing control measures in Kenya. We determined the prevalence of IgG to SARS-CoV-2 in residual blood samples from mothers attending antenatal care services at 2 referral hospitals in Kenya. We used a validated IgG ELISA for SARS-Cov-2 spike protein and adjusted the results for assay sensitivity and specificity. In Kenyatta National Hospital, Nairobi, seroprevalence in August 2020 was 49.9% (95% CI 42.7-58.0). In Kilifi County Hospital seroprevalence increased from 1.3% (95% CI 0.04-4.7) in September to 11.0% (95% CI 6.2-16.7) in November 2020. There has been substantial, unobserved transmission of SARS-CoV-2 in parts of Nairobi and Kilifi Counties.

Background Research has established the development of steroid-induced hyperglycemia as a glucometabolic side effect of high-dose prednisone therapy. Few studies, however, have demonstrated preventative measures that could effectively curtail this side effect in susceptible patients undergoing high-dose prednisone treatment. Objective To assess metformin's prophylactic effectiveness of prednisone-induced hyperglycemia among hematological cancer patients. Setting Prospective randomized controlled trial conducted at the Kenyatta National Hospital Oncology Clinic and Wards, Nairobi, Kenya. Method Non-hyperglycemic hematological cancer patients on current or newly initiated high-dose prednisone-based chemotherapy were randomized to receive metformin 850 mg once then 850 mg twice daily for two successive weeks each or to the control group receiving the standard care. Patients were subjected to once weekly fasting and 2-h postprandial glucose measurements for four weeks. Main outcome measure The primary outcome of measure was the development of hyperglycemia defined by fasting capillary blood glucose values >5.6 mmol/L or 2-h postprandial capillary blood glucose values >7.8 mmol/L. Results Eighteen of 24 randomized patients completed the study (11 control and 7 treatment). The proportion of the control subjects that developed prediabetes was 72.7% (95% confidence interval 45.5–90.9%) using fasting glucose and 54.5% (95% confidence interval 27.3–81.8%) using 2-h postprandial glucose. One treatment group participant developed prediabetes using fasting glucose, representing 14.3% (95% confidence interval 0–42.9%). No prediabetes was detected using the 2-h postprandial glucose. Analysis of mean fasting glucose between the two arms found no significant difference. However, significant differences in mean 2-h postprandial glucose were noted in week 2 ( p = 0.0144), week 3 ( p = 0.0095), and week 4 ( p = 0.0074) of the study. Double dose (1700 mg) metformin was more effective in lowering blood glucose than single dose (850 mg) ( p = 1.0000 (fasting), p = 0.4531(2-h postprandial). Conclusion Metformin's prophylactic effectiveness was demonstrated in this randomized study on new and previously exposed non-diabetic cancer patients on high-dose prednisone-based chemotherapy.

Background: Individually, the red blood cell (RBC) polymorphisms sickle cell trait (HbAS) and α+thalassemia protect against severe Plasmodium falciparum malaria. It has been shown through epidemiological studies that the co-inheritance of both conditions results in a loss of the protection afforded by each, but the biological mechanisms remain unknown. Methods: We used RBCs from >300 donors of various HbAS and α+ thalassemia genotype combinations to study the individual and combinatorial effects of these polymorphisms on a range of putative P. falciparum virulence phenotypes in-vitro, using four well-characterized P. falciparum laboratory strains. We studied cytoadhesion of parasitized RBCs (pRBCs) to the endothelial receptors CD36 and ICAM1, rosetting of pRBCs with uninfected RBCs, and pRBC surface expression of the parasite-derived adhesion molecule P. falciparum erythrocyte membrane protein-1 (PfEMP1). Findings: We confirmed previous reports that sHbAS pRBCs show reduced cytoadhesion, rosetting and PfEMP1 expression levels compared to normal pRBC controls. Furthermore, we found that co-inheritance of HbAS with α+ thalassemia consistently reversed these effects, such that pRBCs of mixed genotype showed levels of cytoadhesion, rosetting and PfEMP1 expression that were indistinguishable from those seen in normal pRBCs. However, pRBCs with α+ thalassemia alone showed parasite strain-specific effects on adhesion, and no consistent reduction in PfEMP1 expression. Interpretation: Our data support the hypothesis that the negative epistasis between HbAS and α+ thalassemia observed in epidemiological studies might be explained by host genotype-specific changes in the pRBC-adhesion properties that contribute to parasite sequestration and disease pathogenesis in vivo. The mechanism by which α+ thalassemia on its own protects against severe malaria remains unresolved.

Summary Background Many investigators have suggested that malaria infection predisposes individuals to bacteraemia. We tested this hypothesis with mendelian randomisation studies of children with the malaria-protective phenotype of sickle-cell trait (HbAS). Methods This study was done in a defined area around Kilifi District Hospital, Kilifi, Kenya. We did a matched case-control study to identify risk factors for invasive bacterial disease, in which cases were children aged 3 months to 13 years who were admitted to hospital with bacteraemia between Sept 16, 1999, and July 31, 2002. We aimed to match two controls, by age, sex, location, and time of recruitment, for every case. We then did a longitudinal case-control study to assess the relation between HbAS and invasive bacterial disease as malaria incidence decreased. Cases were children aged 0–13 years who were admitted to hospital with bacteraemia between Jan 1, 1999, and Dec 31, 2007. Controls were born in the study area between Jan 1, 2006, and June 23, 2009. Finally, we modelled the annual incidence of bacteraemia against the community prevalence of malaria during 9 years with Poisson regression. Results In the matched case-control study, we recruited 292 cases—we recruited two controls for 236, and one for the remaining 56. Sickle-cell disease, HIV, leucocyte haemozoin pigment, and undernutrition were positively associated with bacteraemia and HbAS was strongly negatively associated with bacteraemia (odds ratio 0·36; 95% CI 0·20–0·65). In the longitudinal case-control study, we assessed data from 1454 cases and 10 749 controls. During the study period, the incidence of admission to hospital with malaria per 1000 child-years decreased from 28·5 to 3·45, with a reduction in protection afforded by HbAS against bacteraemia occurring in parallel (p=0·0008). The incidence of hospital admissions for bacteraemia per 1000 child-years also decreased from 2·59 to 1·45. The bacteraemia incidence rate ratio associated with malaria parasitaemia was 6·69 (95% CI 1·31–34·3) and, at a community parasite prevalence of 29% in 1999, 62% (8·2–91) of bacteraemia cases were attributable to malaria. Interpretation Malaria infection strongly predisposes individuals to bacteraemia and can account for more than half of all cases of bacteraemia in malaria-endemic areas. Interventions to control malaria will have a major additional benefit by reducing the burden of invasive bacterial disease. Funding Wellcome Trust.

Our understanding of the basis of severe disease in malaria is incomplete. It is clear that pathology is in part related to the pro-inflammatory nature of the host response but a number of other factors are also thought to be involved, including the interaction between infected erythrocytes and endothelium. This is a complex system involving several host receptors and a major parasite-derived variant antigen (PfEMP1) expressed on the surface of the infected erythrocyte membrane. Previous studies have suggested a role for ICAM-1 in the pathology of cerebral malaria, although these have been inconclusive. In this study we have examined the cytoadherence patterns of 101 patient isolates from varying clinical syndromes to CD36 and ICAM-1, and have used variant ICAM-1 proteins to further characterise this adhesive phenotype. Our results show that increased binding to CD36 is associated with uncomplicated malaria while ICAM-1 adhesion is raised in parasites from cerebral malaria cases.

BACKGROUND: Nontyphoidal Salmonella spp. are among the leading causes of childhood bacteremia in sub-Saharan Africa, yet there are few published clinical series, and the risk factors for acquiring infection are not fully understood. METHODS: We examined data from 166 cases of nontyphoidal Salmonella bacteremia identified during a large prospective study of bacteremia among all children admitted to a district hospital in Kenya. We also investigated the importance of comorbidities, including current malaria parasitemia, recent malaria (detectable Plasmodium falciparum histidine rich protein 2 in the absence of parasitemia), sickle cell disease, malnutrition and human immunodeficiency virus (HIV) infection. RESULTS: Nontyphoidal Salmonella bacteremia was associated with severe malnutrition (33% cases), HIV infection (18% cases), a history of illness >7 days, recent hospital admission, splenomegaly, anemia and recent (but not current) malaria but was not associated with diarrhea. Seventy-seven (46%) children with nontyphoidal Salmonella bacteremia fulfilled World Health Organization clinical criteria for a diagnosis of pneumonia. Independent risk factors for death were diarrhea, tachypnea, HIV infection, severe malnutrition, meningitis and young age. CONCLUSIONS: Clinical diagnosis of invasive nontyphoidal Salmonella infection in African children is difficult without microbiology facilities because clinical features overlap with other conditions. The common risk factors for nontyphoidal Salmonella infection differ from developed countries, with high a prevalence of malnutrition, HIV, malaria and anemia. Children with nontyphoidal Salmonella infection who fulfill World Health Organization clinical criteria for severe pneumonia may receive ineffective therapy in the form of penicillin.

The pathology of sever malaria is in part related to the pro-inflammatory nature of the host response but a number of other factors are also thought to be involved, including the interaction between infected erythrocytes and endothelium. This phenotype involves a range of host receptors and the parasite-derived variant antigen PfEMP1, which is expressed on the surface of the infected erythrocyte membrane. Previous studies have suggested a role for ICAM-1 in the pathology of cerebral malaria, although these were inconclusive. In this study we measured the binding to CD36 and ICAM-1 of patient isolates from varying clinical syndromes under static and flow conditions. We also used mutant ICAM-1 proteins to characterise the key contact residues on ICAM-1 and produce a detailed binding phenotype. Our results show that increased binding to CD36 is associated with uncomplicated malaria while ICAM-1 adhesion under flow conditions is raised in parasites from cerebral malaria cases. The pattern of ICAM-1 binding has also been investigated using mutant ICAM-1 proteins and indicates that isolates from severe malaria are biased towards a binding signature also seen with ITO4, a laboratory isolate selected for binding on human endothelium with similar receptor expression to that seen in the brain.