Effects of remdesivir on SARS-CoV-2 viral dynamics and mortality in viraemic patients hospitalized for COVID-19.

BACKGROUND: Studies on the antiviral effects of remdesivir have shown conflicting results. SARS-CoV-2 viraemia could identify patients in whom antiviral treatment may be particularly beneficial. OBJECTIVES: To investigate antiviral effects and clinical outcomes of remdesivir treatment in viraemic patients. METHODS: Viraemic patients hospitalized for COVID-19 with ratio of arterial oxygen partial pressure to fractional inspired oxygen of ≤300, symptom duration ≤10 days, and estimated glomerular filtration rate ≥30 mL/min were included in a cohort. The rate of serum viral clearance and serum viral load decline, 60 day mortality and in-hospital outcomes were estimated. A subgroup analysis including patients with symptom duration ≤7 days was performed. RESULTS: A total of 318 viraemic patients were included. Thirty-three percent (105/318) received remdesivir. The rate of serum viral clearance [subhazard risk ratio (SHR) 1.4 (95% CI 0.9-2.0), P = 0.11] and serum viral load decline (P = 0.11) were not significantly different between remdesivir-treated patients and controls. However, the rate of serum viral clearance was non-significantly higher [SHR 1.6 (95% CI 1.0-2.7), P = 0.051] and the viral load decline was faster (P = 0.03) in remdesivir-treated patients with symptom duration ≤7 days at admission. The 60 day mortality [HR 1.0 (95% CI 0.6-1.8), P = 0.97] and adverse in-hospital outcomes [OR 1.4 (95% CI 0.8-2.4), P = 0.31] were not significantly different between remdesivir-treated patients and controls. CONCLUSIONS: Remdesivir treatment did not significantly change the duration of SARS-CoV-2 viraemia, decline of serum viral load, 60 day mortality or in-hospital adverse outcomes in patients with ≤10 days of symptoms at admission. Remdesivir appeared to reduce the duration of viraemia in a subgroup of patients with ≤7 days of symptoms at admission.

Safety and tolerability of frozen, capsulized autologous faecal microbiota transplantation. A randomized double blinded phase I clinical trial.

BACKGROUND: Faecal microbiota transplantation (FMT) is recommended treatment for recurrent Clostridioides difficile infection and is studied as a potential modifier of other gastrointestinal and systemic disorders. Autologous FMT limits the potential risks of donor transplant material and enables prophylactic treatment. Capsulized FMT is convenient and accessible, but safety data are lacking. AIMS: To describe safety and tolerability of capsules containing autologous FMT, compared to placebo, in healthy volunteers treated with antibiotics. METHOD: Healthy volunteers without antibiotic exposure during the past three months, that had a negative Clostridioides difficile stool sample, were recruited. Study persons donated faeces for production of capsules containing autologous microbiota. They were then given Clindamycin for seven days to disrupt the intestinal microbiota, which was followed by a two-day washout. Study persons were then randomized (1:1) to unsupervised treatment with autologous faecal matter or placebo, with two capsules twice daily for five days. A standardized questionnaire about side effects and tolerability, daily until day 28, and on days 60 and 180, was completed. RESULTS: Twenty-four study persons were included, all completed the treatment. One person from the placebo and FMT groups each, were lost to follow up from days 21 and 60, respectively. No study person experienced serious side effects, but severe fatigue was reported during the antibiotic period (n = 2). Reported side effects were mild to moderate and there were no significant differences between the groups. Reported general and intestinal health improved significantly and similarly in both groups after the antibiotic treatment. Time to normalized intestinal habits were 17 and 19 days from study start in the placebo group and the FMT group, respectively (p = 0.8). CONCLUSION: Capsulized frozen autologous faecal microbiota transplantation was safe and well tolerated but did not affect time to normalized intestinal habits compared to placebo. TRIAL REGISTRATION: EudraCT 2017-002418-30.

Seasonal variation of diarrhoeal pathogens among Guinea-Bissauan children under five years of age.

BACKGROUND: Diarrhoea remains a major cause of childhood morbidity and mortality in low-income countries (LICs). The frequency of diarrhoeal episodes may vary by season, yet few prospective cohort studies have examined seasonal variation among various diarrhoeal pathogens using multiplex qPCR to analyse bacterial, viral and parasitic pathogens. METHODS: We combined our recent qPCR data of diarrhoeal pathogens (nine bacterial, five viral and four parasitic) among Guinea-Bissauan children under five years old with individual background data, dividing by season. The associations of season (dry winter and rainy summer) and the various pathogens were explored among infants (0-11 months) and young children (12-59 months) and those with and without diarrhoea. RESULTS: Many bacterial pathogens, especially EAEC, ETEC and Campylobacter, and parasitic Cryptosporidium, prevailed in the rainy season, whereas many viruses, particularly the adenovirus, astrovirus and rotavirus proved common in the dry season. Noroviruses were found constantly throughout the year. Seasonal variation was observed in both age groups. CONCLUSION: In childhood diarrhoea in a West African LIC, seasonal variation appears to favour EAEC, ETEC, and Cryptosporidium in the rainy and viral pathogens in the dry season.

Bleeding events among patients concomitantly treated with direct oral anticoagulants and macrolide or fluoroquinolone antibiotics.

Fluoroquinolones and macrolides may, due to a potential drug-drug interaction, increase the concentration of any concomitantly administered direct oral anticoagulant (DOAC) and thereby increase the risk of severe bleeding. However, clinical evidence for such an effect is scarce. The present study aimed to evaluate the association between the use of fluoroquinolones or macrolides and bleeding events in patients with concomitant DOAC use. This was a nationwide cohort study including 19 288 users of DOACs in 2008-2018 using information from Swedish national health registers. We compared the incidence of bleeding events associated with use of fluoroquinolones or macrolides using doxycycline as a negative control. Cox regression was used to calculate crude and adjusted hazard ratios (aHRs) in time windows of various length of follow-up after the start of antibiotic use. The incidence rates for fluoroquinolones and macrolides ranged from 12 to 24 and from 12 to 53 bleeding events per 100 000 patients in the investigated time windows. The aHRs (95% confidence interval) for use of fluoroquinolones and macrolides were 1.29 (0.69-2.44) and 2.60 (0.74-9.08) at the concomitant window, 1.31 (0.84-2.03) and 1.79 (0.75-4.29) at 30 days, and 1.34 (0.99-1.82) and 1.28 (0.62-2.65) at 150 days, respectively. With regard to fluoroquinolones, the present study suggests that the risk of bleeding when combined with DOACs, if any, is small. Codispensation of macrolides in patients on DOACs was not associated with an increased risk of bleeding. However, due to the small number of macrolide users, the results must be interpreted with caution.

Correlation of SARS-CoV-2 Nasopharyngeal CT Values With Viremia and Mortality in Adults Hospitalized With COVID-19.

Background: Both severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viremia and nasopharyngeal viral load have been suggested to be predictors of unfavorable outcome in coronavirus disease 2019 (COVID-19). This study aimed to investigate whether nasopharyngeal viral load is correlated with viremia and unfavorable outcome. Methods: The presence of SARS-CoV-2 RNA was determined in paired nasopharyngeal and serum samples collected at admission from patients hospitalized for COVID-19. Standardized cycle threshold values (CT values) were used as an indicator of viral load. An adjusted logistic regression was used to estimate the risk of viremia at different nasopharyngeal CT values. A Cox regression was used to estimate the risk of 60-day mortality. Results: A total of 688 patients were included. Viremia at admission was detected in 63% (146/230), 46% (105/226), and 31% (73/232) of patients with low, intermediate, and high nasopharyngeal CT values. The adjusted odds ratios of being viremic were 4.4 (95% CI, 2.9-6.8) and 2.0 (95% CI, 1.4-3.0) for patients with low and intermediate CT values, compared with high CT values. The 60-day mortality rate was 37% (84/230), 15% (36/226), and 10% (23/232) for patients with low, intermediate, and high nasopharyngeal CT values at admission, respectively. Adjusted hazard ratios were 2.6 (95% CI, 1.6-4.2) and 1.4 (95% CI, 0.8-2.4) for patients with low and intermediate CT values compared with high CT values. Conclusions: There was a dose-dependent correlation between nasopharyngeal CT values and viremia at admission for COVID-19. Moreover, there was an increased risk of 60-day mortality for patients with low, compared with high, nasopharyngeal CT values.

Chloroquine-susceptible and -resistant Plasmodium falciparum strains survive high chloroquine concentrations by becoming dormant but are eliminated by prolonged exposure.

BACKGROUND: Plasmodium falciparum strains that are resistant to standard-dose chloroquine can be treated by higher chloroquine concentrations maintained for a longer time in vivo. OBJECTIVES: To determine the relative importance of chloroquine concentrations versus exposure time for elimination of chloroquine-susceptible and -resistant P. falciparum in vitro. METHODS: Chloroquine-susceptible (3D7) and -resistant (FCR3) strains were exposed in vitro to 1, 2, 4, 8, 16 or 32 times their respective 90% inhibitory chloroquine concentrations for 3, 5, 7 or 14 days and then followed until recrudescence, or not, by 42 days after the end of exposure. RESULTS: Exposure to chloroquine appeared to eliminate susceptible and resistant parasites, leaving small pyknotic apparently dead parasites. Chloroquine-susceptible and -resistant parasites recrudesced after 3 and 5 days of chloroquine exposure. Recrudescence occurred in one out of four 7 day exposure series but not after 14 days exposure. The median time to recrudescence was 13 to 28 days with a range of 8 to 41 days after the end of exposure. Time to recrudescence after the end of exposure increased with duration of exposure for susceptible and resistant strains (P < 0.001). Time to recrudescence did not correlate with concentrations greater than 1× IC90. CONCLUSIONS: Chloroquine-susceptible and -resistant P. falciparum probably become dormant. Elimination of dormant parasites is primarily dependent upon the duration of chloroquine exposure. Exposure to effective drug concentrations for 7 days eliminates most parasites in vitro. The results support in vivo data indicating that elimination of chloroquine-resistant P. falciparum correlates with Day 7 chloroquine concentrations.

Duration of SARS-CoV-2 viremia and its correlation to mortality and inflammatory parameters in patients hospitalized for COVID-19: a cohort study.

SARS-CoV-2 viremia at admission is associated with high risk for mortality. However, longitudinal data on viremia duration are limited. Viremic patients hospitalized for COVID-19 were included in a cohort. Time to serum viral clearance and the effect of viremia duration on the odds of mortality were calculated. One hundred and twenty-one viremic patients were included. Median age was 62 (IQR 52-71) years and 68% were males. The total in-hospital mortality of the cohort was 33%. Median time from admission to serum viral clearance was 7 (95% CI 6-8) days. Duration of viremia showed a relative risk ratio of 1.40 (95% CI 1.02-1.92) for the odds of mortality in an adjusted multinomial logistic regression. Serum viral clearance coincided with defervescence and decreasing C-reactive protein. Median time to serum viral clearance was 7 days after admission. The odds of mortality increased with 40% for each additional day of viremia.

Convalescent plasma for treatment of COVID-19: study protocol for an open randomised controlled trial in Sweden.

INTRODUCTION: Although there are many studies on the use of convalescent plasma (CP) for treatment of COVID-19, it is not clear (1) which groups of patients may benefit, (2) what dose of plasma to give, or (3) which antibody levels the plasma should contain. Previous phase I/II studies and literature review suggest that CP should only be given to patients with viraemia, that a daily infusion should be given until the patient becomes virus free and that the neutralising antibody titre should preferably be >1:640 METHODS AND ANALYSIS: An open randomised controlled trial enrolling patients with COVID-19, who must be SARS-CoV-2 positive in both airway and blood samples and admitted to a study hospital. Block randomisation 2:1 is to either 200 mL CP (preferably titre ≥1/640) daily for up to 10 days (until virus negative in blood) plus standard care or standard care only (control arm). The primary endpoint is mortality by day 28 after study inclusion. Secondary endpoints include mortality by day 60 and doses of plasma needed to clear viraemia. Assuming a reduced mortality of approximately 30% by the CP therapy and 85%-88% survival in the control arm, approximately 600 participants will be enrolled to the CP therapy arm and 300 participants to the control arm. ETHICS AND DISSEMINATION: Ethical approval has been granted by the Swedish Ethical Review Authority (reference: 2020-06277). Results from this trial will be compiled in a clinical study report, disseminated via journal articles and communicated to stakeholders. TRIAL REGISTRATION NUMBER: NCT04649879.

Prevalence of diarrhoeal pathogens among children under five years of age with and without diarrhoea in Guinea-Bissau.

BACKGROUND: Childhood diarrhoea, a major cause of morbidity and mortality in low-income regions, remains scarcely studied in many countries, such as Guinea-Bissau. Stool sample drying enables later qPCR analyses of pathogens without concern about electricity shortages. METHODS: Dried stool samples of children under five years treated at the Bandim Health Centre in Bissau, Guinea-Bissau were screened by qPCR for nine enteric bacteria, five viruses, and four parasites. The findings of children having and not having diarrhoea were compared in age groups 0-11 and 12-59 months. RESULTS: Of the 429 children- 228 with and 201 without diarrhoea- 96.9% and 93.5% had bacterial, 62.7% and 44.3% viral, and 52.6% and 48.3% parasitic pathogen findings, respectively. Enteroaggregarive Escherichia coli (EAEC; 60.5% versus 66.7%), enteropathogenic E. coli (EPEC; 61.4% versus 62.7%), Campylobacter (53.2% versus 51.8%), and enterotoxigenic E. coli (ETEC; 54.4% versus 44.3%) were the most common bacterial pathogens. Diarrhoea was associated with enteroinvasive E. coli (EIEC)/Shigella (63.3%), ETEC (54.4%), astrovirus (75.0%), norovirus GII (72.6%) and Cryptosporidium (71.2%). The only pathogen associated with severe diarrhoea was EIEC/Shigella (p<0.001). EAEC was found more frequent among the infants, and EIEC/Shigella, Giardia duodenalis and Dientamoeba fragilis among the older children. CONCLUSIONS: Stool pathogens proved common among all the children regardless of them having diarrhoea or not.

Severe Acute Respiratory Syndrome Coronavirus 2 RNA in Serum as Predictor of Severe Outcome in Coronavirus Disease 2019: A Retrospective Cohort Study.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19). This study aimed to determine if SARS-CoV-2 RNA in serum at admission correlated with clinical outcome in COVID-19. METHODS: COVID-19 patients admitted to the infectious diseases department of a tertiary level Swedish hospital and sampled for SARS-CoV-2 RNA in serum at admission during 10 April to 30 June 2020 were included. Primary outcomes were day 28 all-cause mortality and progress to critical disease. RESULTS: The cohort (N = 167) consisted of 106 SARS-CoV-2 RNA serum-negative and 61 serum-positive patients. Median sampling time for initial SARS-CoV-2 in serum was 1 day (interquartile range [IQR], 1-2 days) after admission, corresponding to day 10 (IQR, 8-12) after symptom onset. Median age was 53 years (IQR, 44-67 years) and 63 years (IQR, 52-74 years) for the serum-negative and -positive patients, respectively. In the serum-negative and -positive groups, 3 of 106 and 15 of 61 patients died, respectively.The hazard ratios for critical disease and all-cause mortality were 7.2 (95% confidence interval [CI], 3.0-17) and 8.6 (95% CI, 2.4-30), respectively, for patients with serum-positive compared to serum-negative results. CONCLUSIONS: SARS-CoV-2 RNA in serum at hospital admission indicates a high risk of progression to critical disease and death.

Stable high frequencies of sulfadoxine-pyrimethamine resistance associated mutations and absence of K13 mutations in Plasmodium falciparum 3 and 4 years after the introduction of artesunate plus sulfadoxine-pyrimethamine in Ujjain, Madhya Pradesh, India.

BACKGROUND: Artesunate plus sulfadoxine-pyrimethamine (ASP) is first-line treatment for uncomplicated Plasmodium falciparum malaria in most of India, except for six North-eastern provinces where treatment failure rates were high. In Ujjain, central India, the frequency of mutations associated with increased drug tolerance, but not overt resistance to sulfadoxine and pyrimethamine were 9% and > 80%, respectively, in 2009 and 2010, just prior to the introduction of ASP. The frequency of drug resistance associated mutations in Ujjain in 2015-2016 after 3-4 years of ASP use, are reported. METHODS: Blood samples from patients with P. falciparum mono-infection verified by microscopy were collected on filter-paper at all nine major pathology laboratories in Ujjain city. Codons pfdhfr 16-185, pfdhps 436-632 and K13 407-689 were identified by sequencing. Pfcrt K76T and pfmdr1 N86Y were identified by restriction fragment length polymorphism. RESULTS: Sulfadoxine-pyrimethamine resistance-associated pfdhfr 108 N and 59R alleles were found in 100/104 (96%) and 87/91 (96%) samples, respectively. Pfdhps 437G was found in 10/105 (10%) samples. Double mutant pfdhfr 59R + 108 N were found in 75/81 (93%) samples. Triple mutant pfdhfr 59R + 108 N and pfdhps 437G were found in 6/78 (8%) samples. Chloroquine-resistance-associated pfcrt 76T was found in 102/102 (100%). Pfmdr1 N86 and 86Y were identified in 83/115 (72%) and 32/115 (28%) samples, respectively. CONCLUSION: The frequency of P. falciparum with reduced susceptibility to sulfadoxine-pyrimethamine remained high, but did not appear to have increased significantly since the introduction of ASP. No polymorphisms in K13 associated with decreased artemisinin susceptibility were found. ASP probably remained effective, supporting continued ASP use.

Seasonal variation in the non-specific effects of BCG vaccination on neonatal mortality: three randomised controlled trials in Guinea-Bissau.

The BCG vaccine protects non-specifically against other diseases than tuberculosis. Three randomised controlled trials of early BCG in Guinea-Bissau found a 38% reduction in all-cause neonatal mortality. Little is known about the underlying mechanisms. In Guinea-Bissau, prevalent infectious diseases display distinct seasonality. Revisiting the three trials (>6500 infants) comparing early BCG versus no early BCG in low weight infants on all-cause neonatal mortality over 12 consecutive years, we explored the seasonal variation in BCG's effect on mortality. In a subgroup of participants, adaptive and innate cytokine responses were measured 4 weeks after randomisation. Consistently over the course of the three trials and 12 years, the effect of BCG on all-cause neonatal mortality was particularly beneficial when administered in November to January, coincident with peaking malaria infections. During these months, BCG was also associated with stronger proinflammatory responses to heterologous challenge. Recent studies have suggested a protective effect of BCG against malaria. BCG may also ameliorate immune-compromising fatal effects of placental malaria in the newborn.

High-Dose Chloroquine for Uncomplicated Plasmodium falciparum Malaria Is Well Tolerated and Causes Similar QT Interval Prolongation as Standard-Dose Chloroquine in Children.

Higher chloroquine doses can effectively treat up to 93 to 96% of malaria infections caused by Plasmodium falciparum carrying the resistance-conferring chloroquine resistance transporter (pfcrt) 76T allele. The tolerability of 50 (double the standard dose) and 70 mg/kg total chloroquine doses were assessed in this study. Fifteen 4- to 8-year-old children with uncomplicated malaria were given 10 mg/kg of chloroquine twice daily for 2 days and 5 mg/kg twice daily on the third day. Fifteen additional children were given 5 mg/kg twice daily for 2 more days. Chloroquine concentrations, blood pressure, electrocardiograms (ECGs), parasite density, and adverse events were assessed until day 28. Both dosages were well tolerated, and symptoms resolved by day 3 in parallel with increasing chloroquine concentrations. The median corrected QT (QTc) interval was 12 to 26 ms higher at expected peak concentrations than at day 0 (P < 0.001). Pfcrt 76T was associated with delayed parasite clearance. Day 28 clinical and parasitological responses against P. falciparum with pfcrt 76T were 57% (4/7) and 67% (4/6) after treatment with 50 and 70 mg/kg, respectively. Dosages were well tolerated, and no severe cardiac adverse events occurred. The QTc interval increase was similar to that found in adults taking 25 mg/kg of chloroquine. (This study has been registered at ClinicalTrials.gov under identifier NCT01814423.).

Efficacy of Routine Fecal Microbiota Transplantation for Treatment of Recurrent Clostridium difficile Infection: A Retrospective Cohort Study.

BACKGROUND: Patients with recurrent Clostridium difficile infections (CDIs) constitute an increasing treatment problem. Fecal microbiota transplantation (FMT) has shown promising results of treating recurrent CDI, where treatment with antibiotics fails repeatedly. Our study describes retrospective cohort treated with FMT at two major hospitals in Stockholm. METHODS: Medical records of all patients with recurrent CDI treated with FMT during the period 2013-2017 were reviewed. We evaluated cure of CDI-related diarrhea without relapse 10 weeks after FMT. RESULTS: 47 patients were included. One treatment cured 25 patients (53%), and more than one treatment cured 32 patients (68%). Treatment outcome did not vary significantly with treatment with fresh donor feces or frozen fecal culture, days of use of antibiotics or days of hospitalization prior to CDI, and renal function or time from the first CDI to therapy. Treatment failure was associated with a significantly lower Karnofsky performance status score (70 points vs 90, p=0.02). CONCLUSION: Fecal instillation, for the treatment of relapsing CDI, is a promising approach, with 68% success rate reported in this study. The success rate of FMT is high, regardless of multiple comorbidities, extended use of antibiotics, or long time hospitalization. Although generally FMT is performed with fresh donor feces, our data show that the usage of frozen fecal culture could be an effective treatment alternative in recurrent CDI.

Proof of concept: used malaria rapid diagnostic tests applied for parallel sequencing for surveillance of molecular markers of anti-malarial resistance in Bissau, Guinea-Bissau during 2014-2017.

BACKGROUND: Large-scale surveillance of molecular markers of anti-malarial drug resistance is an attractive method of resistance monitoring, to complement therapeutic efficacy studies in settings where the latter are logistically challenging. METHODS: Between 2014 and 2017, this study sampled malaria rapid diagnostic tests (RDTs), used in routine clinical care, from two health centres in Bissau, Guinea-Bissau. In order to obtain epidemiological insights, RDTs were collected together with patient data on age and sex. A subset of positive RDTs from one of the two sites (n = 2184) were tested for Plasmodium DNA content. Those testing positive for Plasmodium DNA by PCR (n = 1390) were used for library preparation, custom designed dual indexing and next generation Miseq targeted sequencing of Plasmodium falciparum genes pfcrt, pfmdr1, pfdhfr, pfdhps and pfk13. RESULTS: The study found a high frequency of the pfmdr1 codon 86N at 88-97%, a significant decrease of the pfcrt wildtype CVMNK haplotype and elevated levels of the pfdhfr/pfdhps quadruple mutant ranging from 33 to 51% between 2014 and 2017. No polymorphisms indicating artemisinin tolerance were discovered. The demographic data indicate a large proportion of young adults (66%, interquartile range 11-28 years) presenting with P. falciparum infections. While a total of 5532 gene fragments were successfully analysed on a single Illumina Miseq flow cell, PCR-positivity from the library preparation varied considerably from 13 to 87% for different amplicons. Furthermore, pre-screening of samples for Plasmodium DNA content proved necessary prior to library preparation. CONCLUSIONS: This study serves as a proof of concept for using leftover clinical material (used RDTs) for large-scale molecular surveillance, encompassing the inherent complications regarding to methodology and analysis when doing so. Factors such as RDT storage prior to DNA extraction and parasitaemia of the infection are likely to have an effect on whether or not parasite DNA can be successfully analysed, and are considered part of the reason the data yield is suboptimal. However, given the necessity of molecular surveillance of anti-malarial resistance in settings where poor infrastructure, poor economy, lack of educated staff and even surges of political instability remain major obstacles to performing clinical studies, obtaining the necessary data from used RDTs, despite suboptimal output, becomes a feasible, affordable and hence a justifiable method.

Artemether-lumefantrine dosing for malaria treatment in young children and pregnant women: A pharmacokinetic-pharmacodynamic meta-analysis.

BACKGROUND: The fixed dose combination of artemether-lumefantrine (AL) is the most widely used treatment for uncomplicated Plasmodium falciparum malaria. Relatively lower cure rates and lumefantrine levels have been reported in young children and in pregnant women during their second and third trimester. The aim of this study was to investigate the pharmacokinetic and pharmacodynamic properties of lumefantrine and the pharmacokinetic properties of its metabolite, desbutyl-lumefantrine, in order to inform optimal dosing regimens in all patient populations. METHODS AND FINDINGS: A search in PubMed, Embase, ClinicalTrials.gov, Google Scholar, conference proceedings, and the WorldWide Antimalarial Resistance Network (WWARN) pharmacology database identified 31 relevant clinical studies published between 1 January 1990 and 31 December 2012, with 4,546 patients in whom lumefantrine concentrations were measured. Under the auspices of WWARN, relevant individual concentration-time data, clinical covariates, and outcome data from 4,122 patients were made available and pooled for the meta-analysis. The developed lumefantrine population pharmacokinetic model was used for dose optimisation through in silico simulations. Venous plasma lumefantrine concentrations 7 days after starting standard AL treatment were 24.2% and 13.4% lower in children weighing <15 kg and 15-25 kg, respectively, and 20.2% lower in pregnant women compared with non-pregnant adults. Lumefantrine exposure decreased with increasing pre-treatment parasitaemia, and the dose limitation on absorption of lumefantrine was substantial. Simulations using the lumefantrine pharmacokinetic model suggest that, in young children and pregnant women beyond the first trimester, lengthening the dose regimen (twice daily for 5 days) and, to a lesser extent, intensifying the frequency of dosing (3 times daily for 3 days) would be more efficacious than using higher individual doses in the current standard treatment regimen (twice daily for 3 days). The model was developed using venous plasma data from patients receiving intact tablets with fat, and evaluations of alternative dosing regimens were consequently only representative for venous plasma after administration of intact tablets with fat. The absence of artemether-dihydroartemisinin data limited the prediction of parasite killing rates and recrudescent infections. Thus, the suggested optimised dosing schedule was based on the pharmacokinetic endpoint of lumefantrine plasma exposure at day 7. CONCLUSIONS: Our findings suggest that revised AL dosing regimens for young children and pregnant women would improve drug exposure but would require longer or more complex schedules. These dosing regimens should be evaluated in prospective clinical studies to determine whether they would improve cure rates, demonstrate adequate safety, and thereby prolong the useful therapeutic life of this valuable antimalarial treatment.

Direct whole-genome sequencing of Plasmodium falciparum specimens from dried erythrocyte spots.

BACKGROUND: Plasmodium falciparum malaria remains a major health burden and genomic research represents one of the necessary approaches for continued progress towards malaria control and elimination. Sample acquisition for this purpose is troublesome, with the majority of malaria-infected individuals living in rural areas, away from main infrastructure and the electrical grid. The aim of this study was to describe a low-tech procedure to sample P. falciparum specimens for direct whole genome sequencing (WGS), without use of electricity and cold-chain. METHODS: Venous blood samples were collected from malaria patients in Bandim, Guinea-Bissau and leukocyte-depleted using Plasmodipur filters, the enriched parasite sample was spotted on Whatman paper and dried. The samples were stored at ambient temperatures and subsequently used for DNA-extraction. Ratios of parasite:human content of the extracted DNA was assessed by qPCR, and five samples with varying parasitaemia, were sequenced. Sequencing data were used to analyse the sample content, as well as sample coverage and depth as compared to the 3d7 reference genome. RESULTS: qPCR revealed that 73% of the 199 samples were applicable for WGS, as defined by a minimum ratio of parasite:human DNA of 2:1. WGS revealed an even distribution of sequence data across the 3d7 reference genome, regardless of parasitaemia. The acquired read depths varied from 16 to 99×, and coverage varied from 87.5 to 98.9% of the 3d7 reference genome. SNP-analysis of six genes, for which amplicon sequencing has been performed previously, confirmed the reliability of the WGS-data. CONCLUSION: This study describes a simple filter paper based protocol for sampling P. falciparum from malaria patients for subsequent direct WGS, enabling acquisition of samples in remote settings with no access to electricity.

[Rapid improvement of tick-borne encephalitis after treatment with corticosteroids]. / Patient med TBE förbättrades snabbt vid behandling med kortison - Evidens saknas dock för värdet av immunmodulerande terapi.

Rapid improvement of tick-borne encephalitis after treatment with corticosteroids Tick-borne encephalitis (TBE) is a viral disease transmitted by ticks. The virus is divided into three subtypes named Western, Siberian and Far Eastern TBE virus (TBEV). Western TBEV is endemic in parts of Europe and Sweden and typically causes a biphasic illness with influenza-like symptoms followed by neurological symptoms ranging from mild meningitis to severe meningoencephalitis and death. Despite an effective vaccine, TBE is increasing in Sweden and Europe. The pathogenesis of TBE is poorly understood; direct infection of neurons as well as immunological reactions mediated by T-cells have been implicated. In some endemic areas, such as Lithuania, patients with TBE are given corticosteroids based on the clinical experience that it results in rapid improvement. However, existing retrospective studies have failed to show beneficial effects of corticosteroids compared to symptomatic treatment in patients with TBE. This case report describes how an elderly man with meningoencephalitis and cranial nerve palsy due to TBE  rapidly improved after administration of high dose corticosteroids.

High throughput resistance profiling of Plasmodium falciparum infections based on custom dual indexing and Illumina next generation sequencing-technology.

Genetic polymorphisms in P. falciparum can be used to indicate the parasite's susceptibility to antimalarial drugs as well as its geographical origin. Both of these factors are key to monitoring development and spread of antimalarial drug resistance. In this study, we combine multiplex PCR, custom designed dual indexing and Miseq sequencing for high throughput SNP-profiling of 457 malaria infections from Guinea-Bissau, at the cost of 10 USD per sample. By amplifying and sequencing 15 genetic fragments, we cover 20 resistance-conferring SNPs occurring in pfcrt, pfmdr1, pfdhfr, pfdhps, as well as the entire length of pfK13, and the mitochondrial barcode for parasite origin. SNPs of interest were sequenced with an average depth of 2,043 reads, and bases were called for the various SNP-positions with a p-value below 0.05, for 89.8-100% of samples. The SNP data indicates that artemisinin resistance-conferring SNPs in pfK13 are absent from the studied area of Guinea-Bissau, while the pfmdr1 86 N allele is found at a high prevalence. The mitochondrial barcodes are unanimous and accommodate a West African origin of the parasites. With this method, very reliable high throughput surveillance of antimalarial drug resistance becomes more affordable than ever before.