Distinct and dynamic activation profiles of circulating dendritic cells and monocytes in mild COVID-19 and after yellow fever vaccination.

Dysregulation of the myeloid cell compartment is a feature of severe disease in hospitalized COVID-19 patients. Here, we investigated the response of circulating dendritic cell (DC) and monocyte subpopulations in SARS-CoV-2 infected outpatients with mild disease and compared it to the response of healthy individuals to yellow fever vaccine virus YF17D as a model of a well-coordinated response to viral infection. In SARS-CoV-2-infected outpatients circulating DCs were persistently reduced for several weeks whereas after YF17D vaccination DC numbers were decreased temporarily and rapidly replenished by increased proliferation until 14 days after vaccination. The majority of COVID-19 outpatients showed high expression of CD86 and PD-L1 in monocytes and DCs early on, resembling the dynamic after YF17D vaccination. In a subgroup of patients, low CD86 and high PD-L1 expression were detected in monocytes and DCs coinciding with symptoms, higher age, and lower lymphocyte counts. This phenotype was similar to that observed in severely ill COVID-19 patients, but less pronounced. Thus, prolonged reduction and dysregulated activation of blood DCs and monocytes were seen in a subgroup of symptomatic non-hospitalized COVID-19 patients while a transient coordinated activation was characteristic for the majority of patients with mild COVID-19 and the response to YF17D vaccination.

Persistent immune abnormalities discriminate post-COVID syndrome from convalescence.

BACKGROUND: Innate lymphoid cells (ILCs) are key organizers of tissue immune responses and regulate tissue development, repair, and pathology. Persistent clinical sequelae beyond 12 weeks following acute COVID-19 disease, named post-COVID syndrome (PCS), are increasingly recognized in convalescent individuals. ILCs have been associated with the severity of COVID-19 symptoms but their role in the development of PCS remains poorly defined. METHODS AND RESULTS: Here, we used multiparametric immune phenotyping, finding expanded circulating ILC precursors (ILCPs) and concurrent decreased group 2 innate lymphoid cells (ILC2s) in PCS patients compared to well-matched convalescent control groups at > 3 months after infection or healthy controls. Patients with PCS showed elevated expression of chemokines and cytokines associated with trafficking of immune cells (CCL19/MIP-3b, FLT3-ligand), endothelial inflammation and repair (CXCL1, EGF, RANTES, IL-1RA, PDGF-AA). CONCLUSION: These results define immunological parameters associated with PCS and might help find biomarkers and disease-relevant therapeutic strategies.

Studying temporal titre evolution of commercial SARS-CoV-2 assays reveals significant shortcomings of using BAU standardization for comparison.

BACKGROUND: Measuring specific anti-SARS-CoV-2 antibodies has become one of the main epidemiological tools to survey the ongoing SARS-CoV-2 pandemic, but also vaccination response. The WHO made available a set of well-characterized samples derived from recovered individuals to allow normalization between different quantitative anti-Spike assays to defined Binding Antibody Units (BAU). METHODS: To assess sero-responses longitudinally, a cohort of ninety-nine SARS-CoV-2 RT-PCR positive subjects was followed up together with forty-five vaccinees without previous infection but with two vaccinations. Sero-responses were evaluated using a total of six different assays: four measuring anti-Spike proteins (converted to BAU), one measuring anti-Nucleocapsid proteins and one SARS-CoV-2 surrogate virus neutralization. Both cohorts were evaluated using the Euroimmun Anti-SARS-CoV-2-ELISA anti-S1 IgG and the Roche Elecsys Anti-SARS-CoV-2 anti-S1 assay. RESULTS: In SARS-CoV-2-convalesce subjects, the BAU-sero-responses of Euroimmun Anti-SARS-CoV-2-ELISA anti-S1 IgG and Roche Elecsys Anti-SARS-CoV-2 anti-S1 peaked both at 47 (43-51) days, the first assay followed by a slow decay thereafter (> 208 days), while the second assay not presenting any decay within one year. Both assay values in BAUs are only equivalent a few months after infection, elsewhere correction factors up to 10 are necessary. In contrast, in infection-naive vaccinees the assays perform similarly. CONCLUSION: The results of our study suggest that the establishment of a protective correlate or vaccination booster recommendation based on different assays, although BAU-standardised, is still challenging. At the moment the characteristics of the available assays used are not related, and the BAU-standardisation is unable to correct for that.

Putting global health high on the agenda of medical schools.

In this opinion paper, we reflect on global health and global health education as well as challenges that the coming generation are likely to face. As the field is rapidly changing, it is vital to critically reflect categories of "global south" and "global north" as geographical boundaries, and rather think in terms of inequalities that are present in all countries. Global perspectives on health are useful to analyze structural challenges faced in all health care systems and help understand the diversity of cultures and patients' concepts of disease. We first discuss burning questions and important challenges in the field and how those challenges are tackled. Rather than going into detail on topical issues, we reflect on approaches and attitudes that we think are important in global health education and present opportunities and challenges for young scholars who are interested in working in this field.

Head-to-head evaluation of seven different seroassays including direct viral neutralisation in a representative cohort for SARS-CoV-2.

A number of seroassays are available for SARS-CoV-2 testing; yet, head-to-head evaluations of different testing principles are limited, especially using raw values rather than categorical data. In addition, identifying correlates of protection is of utmost importance, and comparisons of available testing systems with functional assays, such as direct viral neutralisation, are needed.We analysed 6658 samples consisting of true-positives (n=193), true-negatives (n=1091), and specimens of unknown status (n=5374). For primary testing, we used Euroimmun-Anti-SARS-CoV-2-ELISA-IgA/IgG and Roche-Elecsys-Anti-SARS-CoV-2. Subsequently virus-neutralisation, GeneScriptcPass, VIRAMED-SARS-CoV-2-ViraChip, and Mikrogen-recomLine-SARS-CoV-2-IgG were applied for confirmatory testing. Statistical modelling generated optimised assay cut-off thresholds. Sensitivity of Euroimmun-anti-S1-IgA was 64.8%, specificity 93.3% (manufacturer's cut-off); for Euroimmun-anti-S1-IgG, sensitivity was 77.2/79.8% (manufacturer's/optimised cut-offs), specificity 98.0/97.8%; Roche-anti-N sensitivity was 85.5/88.6%, specificity 99.8/99.7%. In true-positives, mean and median Euroimmun-anti-S1-IgA and -IgG titres decreased 30/90 days after RT-PCR-positivity, Roche-anti-N titres decreased significantly later. Virus-neutralisation was 80.6% sensitive, 100.0% specific (≥1:5 dilution). Neutralisation surrogate tests (GeneScriptcPass, Mikrogen-recomLine-RBD) were >94.9% sensitive and >98.1% specific. Optimised cut-offs improved test performances of several tests. Confirmatory testing with virus-neutralisation might be complemented with GeneScriptcPassTM or recomLine-RBD for certain applications. Head-to-head comparisons given here aim to contribute to the refinement of testing strategies for individual and public health use.

Rapid prototyping vaccine approach in mice against multi-drug resistant Gram-negative organisms from clinical isolates based on outer membrane vesicles.

Hospital-acquired infections due to multi-drug resistant Gram-negative organisms (MDRGNO) pose a major threat to global health. A vaccine preventing colonization and consecutive infection with MDRGNO could be particularly valuable, as therapeutic options become increasingly limited. Outer membrane vesicles (OMV) of Escherichia coli strain CFT073 as well as three MDRGNO strains that had caused severe infections in humans were administered intranasally to mice, with and without cholera toxin as an adjuvant. The humoral immune responses were comparatively matched with the sera of patients, who had suffered an infection caused by the respective bacterium. Additionally, systemic and local toxicity was evaluated. Intranasal vaccination with OMV could elicit solid humoral immune responses (total IgM and IgG), specific for the respective MDRGNO in mice; decoration of vital bacterial membranes with antibodies was comparable to patients who had survived systemic infection with the respective bacterial isolate. After intranasal vaccination of mice with OMV no signs of local or systemic toxicity were observed. Intranasal vaccination with OMV may open up a rapid vaccine approach to prevent colonization and/or infection with pathogenic MDRGNOs, especially in an outbreak setting within a hospital. It may also be an option for patients who have to undergo elective interventions in centers with a high risk of infection for certain common MDRGNO. Future studies need to include challenge experiments as well as phase I trials in humans.

From first to second wave: follow-up of the prospective COVID-19 cohort (KoCo19) in Munich (Germany).

BACKGROUND: In the 2nd year of the COVID-19 pandemic, knowledge about the dynamics of the infection in the general population is still limited. Such information is essential for health planners, as many of those infected show no or only mild symptoms and thus, escape the surveillance system. We therefore aimed to describe the course of the pandemic in the Munich general population living in private households from April 2020 to January 2021. METHODS: The KoCo19 baseline study took place from April to June 2020 including 5313 participants (age 14 years and above). From November 2020 to January 2021, we could again measure SARS-CoV-2 antibody status in 4433 of the baseline participants (response 83%). Participants were offered a self-sampling kit to take a capillary blood sample (dry blood spot; DBS). Blood was analysed using the Elecsys® Anti-SARS-CoV-2 assay (Roche). Questionnaire information on socio-demographics and potential risk factors assessed at baseline was available for all participants. In addition, follow-up information on health-risk taking behaviour and number of personal contacts outside the household (N = 2768) as well as leisure time activities (N = 1263) were collected in summer 2020. RESULTS: Weighted and adjusted (for specificity and sensitivity) SARS-CoV-2 sero-prevalence at follow-up was 3.6% (95% CI 2.9-4.3%) as compared to 1.8% (95% CI 1.3-3.4%) at baseline. 91% of those tested positive at baseline were also antibody-positive at follow-up. While sero-prevalence increased from early November 2020 to January 2021, no indication of geospatial clustering across the city of Munich was found, although cases clustered within households. Taking baseline result and time to follow-up into account, men and participants in the age group 20-34 years were at the highest risk of sero-positivity. In the sensitivity analyses, differences in health-risk taking behaviour, number of personal contacts and leisure time activities partly explained these differences. CONCLUSION: The number of citizens in Munich with SARS-CoV-2 antibodies was still below 5% during the 2nd wave of the pandemic. Antibodies remained present in the majority of SARS-CoV-2 sero-positive baseline participants. Besides age and sex, potentially confounded by differences in behaviour, no major risk factors could be identified. Non-pharmaceutical public health measures are thus still important.

Describing nearly two decades of Chagas disease in Germany and the lessons learned: a retrospective study on screening, detection, diagnosis, and treatment of Trypanosoma cruzi infection from 2000 - 2018.

BACKGROUND: The highly complex and largely neglected Chagas disease (CD) has become a global health problem due to population movements between Latin America and non-endemic countries, as well as non-vectorial transmission routes. Data on CD testing and treatment from routine patient care in Germany of almost two decades was collected and analysed. METHODS: German laboratories offering diagnostics for chronic Trypanosoma cruzi (T. cruzi) infection in routine patient care were identified. All retrievable data on tests performed during the years of 2000-2018 were analysed. Additional clinical information regarding patients diagnosed with CD was collected through questionnaires. RESULTS: Five German laboratories with diagnostics for T. cruzi infection in routine patient care were identified. Centres in Hamburg and Munich offered two independent serological tests to confirm the CD diagnosis, as recommended by WHO during the entire time period 2000-2018. Overall, a total of n = 10,728 independent tests involving n = 5991 individuals were identified with a progressive increase in testing rates over time, only n = 130 (16.0%) of the tested individuals with known nationality came from CD endemic countries. Of all test units conducted at the included institutes, a total of n = 347/10,728 (3.2%) tests on CD were positive, of which n = 200/347 (57.6%) were ELISA, n = 133/347 (38.3%) IFT, n = 10/347 (2.9%) PCR, and n = 4/347 (1.2%) RDT. Of the n = 5991 individuals only n = 81 (1.4%) with chronic infection were identified, n = 52 females and n = 28 males. Additional clinical information could only be collected from n = 47. CONCLUSION: The results of this study give insight into the deployment of screening, detection, diagnosis, and treatment of T. cruzi over the last two decades in Germany and existing deficits therein; the creation of guidelines for Germany could be a step forward to improve the existing gaps.

Publisher Correction to: Protocol of a population-based prospective COVID-19 cohort study Munich, Germany (KoCo19).

An amendment to this paper has been published and can be accessed via the original article.

Protocol of a population-based prospective COVID-19 cohort study Munich, Germany (KoCo19).

BACKGROUND: Due to the SARS-CoV-2 pandemic, public health interventions have been introduced globally in order to prevent the spread of the virus and avoid the overload of health care systems, especially for the most severely affected patients. Scientific studies to date have focused primarily on describing the clinical course of patients, identifying treatment options and developing vaccines. In Germany, as in many other regions, current tests for SARS-CoV2 are not conducted on a representative basis and in a longitudinal design. Furthermore, knowledge about the immune status of the population is lacking. Nonetheless, these data are needed to understand the dynamics of the pandemic and hence to appropriately design and evaluate interventions. For this purpose, we recently started a prospective population-based cohort in Munich, Germany, with the aim to develop a better understanding of the state and dynamics of the pandemic. METHODS: In 100 out of 755 randomly selected constituencies, 3000 Munich households are identified via random route and offered enrollment into the study. All household members are asked to complete a baseline questionnaire and subjects ≥14 years of age are asked to provide a venous blood sample of ≤3 ml for the determination of SARS-CoV-2 IgG/IgA status. The residual plasma and the blood pellet are preserved for later genetic and molecular biological investigations. For twelve months, each household member is asked to keep a diary of daily symptoms, whereabouts and contacts via WebApp. If symptoms suggestive for COVID-19 are reported, family members, including children < 14 years, are offered a pharyngeal swab taken at the Division of Infectious Diseases and Tropical Medicine, LMU University Hospital Munich, for molecular testing for SARS-CoV-2. In case of severe symptoms, participants will be transferred to a Munich hospital. For one year, the study teams re-visits the households for blood sampling every six weeks. DISCUSSION: With the planned study we will establish a reliable epidemiological tool to improve the understanding of the spread of SARS-CoV-2 and to better assess the effectiveness of public health measures as well as their socio-economic effects. This will support policy makers in managing the epidemic based on scientific evidence.

Intermittent screening and treatment with artemether-lumefantrine versus intermittent preventive treatment with sulfadoxine-pyrimethamine for malaria in pregnancy: a facility-based, open-label, non-inferiority trial in Nigeria.

BACKGROUND: The spread of SP resistance may compromise the effectiveness of intermittent preventive treatment of malaria in pregnancy (MiP) with sulfadoxine-pyrimethamine (IPTp-SP) across Africa. However, there is no recommended alternative medicine for IPTp or alternative strategy for prevention of MiP. This poses problems for the prevention of MiP. This study investigated, whether screening with a rapid diagnostic test for malaria at routine antenatal clinic attendances and treatment of only those who are positive (intermittent screening and treatment) with artemether-lumefantrine is as effective and safe as IPTp-SP in pregnant women. METHODS: During antenatal clinic sessions at the General Hospital Calabar, Nigeria, held between October 2013 and November 2014, 459 pregnant women were randomized into either the current standard IPTp-SP or intermittent screening and treatment with artemether-lumefantrine (ISTp-AL). All women received a long-lasting insecticide-treated net at enrolment. Study women had a maximum of four scheduled visits following enrolment. Haemoglobin concentration and peripheral parasitaemia were assessed in the third trimester (36-40 weeks of gestation). Birth weight was documented at delivery or within a week for babies delivered at home. RESULTS: In the third trimester, the overall prevalence of severe anaemia (Hb < 8 g/dl) and moderate (8-10.9 g/dl) anaemia was 0.8 and 27.7%, respectively, and was similar in both treatment groups (p = 0.204). The risk of third-trimester severe anaemia did not differ significantly between both treatment arms (risk difference - 1.75% [95% CI - 4.16 to 0.66]) although the sample was underpowered for this outcome due to several participants being unavailable to give a blood sample. The risk of third-trimester maternal parasitaemia was significantly lower in the ISTp-AL arm (RD - 3.96% [95% CI - 7.76 to - 0.16]). The risk of low birthweight was significantly lower in the ISTp-AL arm after controlling for maternal age, gravidity and baseline parasitaemia (risk difference - 1.53% [95% CI - 1.54 to - 1.15]). Women in the ISTp-AL arm complained of fever more frequently compared to women in the IPTp-SP arm (p = 0.022). CONCLUSIONS: The trial results suggest that in an area of high malaria transmission with moderate sulfadoxine-pyrimethamine resistance, ISTp with artemether-lumefantrine may be an effective strategy for controlling malaria in pregnancy. Trial registration PACTR, PACTR201308000543272. Registered 29 April 2013, http://www.pactr.org/ATMWeb/appmanager/atm/atmregistry?dar=true&tNo=PACTR201308000543272.

Glucose-6-phosphate dehydrogenase activity measured by spectrophotometry and associated genetic variants from the Oromiya zone, Ethiopia.

BACKGROUND: The study aimed to gain first data on the prevalence of G6PD enzyme deficiency measured by spectrophotometry and associated genetic variants in Jimma and surroundings, Ethiopia. The area is a Plasmodium vivax endemic region, but 8-aminoquinolines such as primaquine are not recommended as G6PD testing is not available. METHODS: Healthy volunteers were recruited at Jimma University, Ethiopia. Enzyme activity was tested by spectrophotometry at the University of Ulm, Germany. A G6PD RDT (Binax NOW® G6PD, Alere, USA) was additionally performed. The G6PD gene was analysed for polymorphisms in a sub-population. Tests for haemoglobinopathies and the presence of malaria parasites were conducted. RESULTS: No severe or moderate (cut-off 60%) G6PD deficiency was found in 206 volunteers. Median male activity was 6.1 U/g Hb. Eleven participants (5.4%) showed activities between 70 and 80%. No haemoglobinopathy was detected. None of the subjects showed asymptomatic parasitaemia. One G6PD-A+ variant (A376G) and one new non-synonymous mutation (G445A) were found. CONCLUSIONS: As the prevalence of G6PD deficiency seems low in this area, the use of 8-aminoquinolines should be encouraged. However, reliable G6PD testing methods have to be implemented and safe cut-off levels need to be defined.

Prevalence and antibiotic susceptibility pattern of CTX-M type extended-spectrum ß-lactamases among clinical isolates of gram-negative bacilli in Jimma, Ethiopia.

BACKGROUND: The prevalence of extended-spectrum ß-lactamases (ESBLs) have been reported in clinical isolates obtained from various hospitals in Ethiopia. However, there is no data on the prevalence and antibiotic susceptibility patterns of CTX-M type ESBL produced by Gram-negative bacilli. The aim of this study was to determine the frequency and distribution of the blaCTX-M genes and the susceptibility patterns in ESBL producing clinical isolates of Gram-negative bacilli in Jimma University Specialized Hospital (JUSH), southwest Ethiopia. METHODS: A total of 224 non-duplicate and pure isolates obtained from clinically apparent infections, were included in the study. Identification of the isolates was performed by MALDI-TOF mass spectrometry. Susceptibility testing and ESBL detection was performed using VITEK® 2, according to EUCAST v4.0 guidelines. Genotypic analysis was performed using Check-MDR CT103 Microarrays. RESULTS: Of the total 112 (50.0%) isolates screen positive for ESBLs, 63.4% (71/112) tested positive for ESBL encoding genes by Check-MDR array, which corresponds to 91.8% (67/73) of the total Enterobacteriaceae and 10.3% (4/39) of nonfermenting Gram-negative bacilli. Among the total ESBL gene positive isolates, 95.8% (68/71) carried blaCTX-M genes with CTX-M group 1 type15 being predominant (66/68; 97.1% of CTX-M genes). The blaCTX-M carrying Enterobacteriaceae (n = 64) isolates showed no resistance against imipenem and meropenem and a moderate resistance rate against tigecycline (14.1%), fosfomycin (10.9%) and amikacin (1.6%) suggesting the effectiveness of these antibiotics against most isolates. On the other hand, all the blaCTX-M positive Enterobacteriaceae showed a multidrug resistant (MDR) phenotype with remarkable co-resistances (non-susceptibility rates) to aminoglycosides (92.2%), fluoroquinolones (78.1%) and trimethoprim/sulfamethoxazol (92.2%). CONCLUSIONS: This study demonstrates a remarkably high prevalence of blaCTX-M genes among ESBL-producing isolates. The high level of resistance to ß-lactam and non-ß-lactam antibiotics as well as the trend to a MDR profile associated with the blaCTX-M genes are alarming and emphasize the need for routine diagnostic antimicrobial susceptibility testing for appropriate choice of antimicrobial therapy.

Prevalence of the Pfdhfr and Pfdhps mutations among asymptomatic pregnant women in Southeast Nigeria.

Sulfadoxine-pyrimethamine (SP) is the recommended drug for intermittent preventive treatment of malaria in pregnancy in most of sub-Saharan Africa. Resistance to SP is related to mutations in the dhfr and dhps gene of Plasmodium falciparum. This study determined the prevalence of Pfdhfr and Pfdhps polymorphisms found in asymptomatic pregnant women attending antenatal care in Calabar, Nigeria. From October 2013 to November 2014, asymptomatic pregnant women attending antenatal care clinics were enrolled after obtaining informed consent. Malaria diagnosis testing was done using thick and thin smears. Dried blood spot filter papers were collected. Parasite DNA was extracted from the filter papers using a chelex extraction. Extraction was followed by nested PCR and restriction enzyme digestion. P. falciparum infection was detected by microscopy in 7% (32/459) participants. Twenty-eight P. falciparum isolates were successfully genotyped. In the Pfdhfr gene, the triple mutation was almost fixed; S108N mutation was (100%), N51I (93%) and C59R mutations (93%), whereas the I164L mutation was absent. The prevalence of Pfdhps S436A, A437G, A581G and A613S mutations was 82.1% (23/28), 96.4% (27/28), 71.4% (20/28) and 71.4% (20/28) respectively. The K540E mutation was absent. The prevalence of the Pfdhfr triple mutation IRNI was 92.9% (26/28). The efficacy of SP as IPTp in Southeast Nigeria may be severely threatened. The continuous monitoring of SP molecular markers of resistance is required to assess thresholds. The evaluation of alternative preventive treatment strategies and drug options for preventing malaria in pregnancy may be necessary.

Retrospective clinical case series study in 2017 identifies Plasmodium knowlesi as most frequent Plasmodium species in returning travellers from Thailand to Germany.

Febrile illnesses are common in travellers returning from south-east Asia. However, malaria is a rare diagnosis in this population. A series of Plasmodium knowlesi infections was noted in German travellers returning from Thailand since 2012. Infectious disease and tropical medicine facilities registered by the German Society for Tropical Medicine and International Health were contacted in March 2017, and asked to report previous P. knowlesi cases. In addition, surveillance data from the Robert Koch-Institute were analysed. The facilities reported a total of six P. knowlesi-positive cases, all were returning travellers from Thailand. The P. knowlesi-positive cases made up 6/9 of all diagnosed malaria cases imported from Thailand in the time period 2012 to 2017. In 4/5 of cases where a malaria rapid diagnostic test had been applied it revealed a negative result. P. knowlesi is an important differential diagnosis in travellers returning from south-east Asia with itineraries that include Thailand. This study highlights the importance of this Plasmodium species in this patient subgroup. Whenever malaria is suspected in a returning traveller from Thailand, P. knowlesi should be taken into consideration and a differential PCR be executed as currently the unequivocal diagnosis of P. knowlesi is based on nuclear amplification techniques.

First report on bla NDM-1-producing Acinetobacter baumannii in three clinical isolates from Ethiopia.

BACKGROUND: Multidrug-resistant Gram-negative bacterial infections are recognized as one of the major threats to global health. In this study, we describe for the first time bla NDM-1 gene carrying organisms from Ethiopia consisting of three Acinetobacter baumannii isolates from patients in Jimma. METHODS: Besides phenotypic antimicrobial susceptibility testing, molecular strain typing and sequencing was performed to describe the phylogenetic relation of the Ethiopian isolates in detail in relation to published isolates from all over the globe. RESULTS AND DISCUSSION: Three multi-resistant, bla NDM-1-positive Acinetobacter baumannii isolates, most likely a local clonal diffusion, were isolated. Two of the three isolates described within this study were untreatable with the locally available antimicrobials and were only susceptible to polymyxin B and amikacin. The genome sequences confirmed the isolates to be distinct from the outbreak strains reported from Kenya, the only other characterized bla NDM-1 positive Acinetobacter baumannii strains in East Africa so far. Up to date, no other bacterial species were found to harbour the gene cassette in Jimma and conjugation to E. coli was not successful under laboratory conditions. However, natural transmission to other bacteria seems likely, given the evident lack of hygienic precautions due to limited resource settings. CONCLUSIONS: The detected isolates could solely be the tip of the iceberg regarding the presence of NDM-1 producing organisms in the region, as only a limited number of bacterial isolates were evaluated so far and until recently, susceptibility testing and isolation of bacteria could hardly be performed in clinical patient care. These multi-drug resistant organisms pose a serious threat to antimicrobial treatments in Jimma, Ethiopia.

Drug resistance and population structure of M.tuberculosis isolates from prisons and communities in Ethiopia.

BACKGROUND: The population structure and drug resistance pattern of Mycobacterium tuberculosis complex (MTBC) isolates in Ethiopian prisons and some communities is still unknown. METHODS: A comparative cross sectional study was conducted on 126 MTBC strains isolated from prisons and communities in southwestern, southern and eastern Ethiopia. Phenotypic drug susceptibility testing was performed with the MGIT960 system. Combined 24-loci Mycobacterium interspersed repetitive unit-variable number tandem repeat and spacer oligonucleotide typing methods were used to study the MTBC population structure. The obtained data from prisons and communities were compared using statistical tests and regression analysis. RESULTS: A diverse population structure with 11 different lineages and sub-lineages was identified. The predominant strains were the recently described Ethiopia_H37Rv like (27.52%) and Ethiopia_3 (16.51%) with equal lineage distribution between prisons and communities. 28.57% of prison strains and 31.82% of community strains shared the identical genotype with at least one other strain. The multidrug-resistance (MDR) prevalence of the community was 2.27% whereas that of prisons was 9.52%. The highest mono resistance was seen against streptomycin (15.89%). CONCLUSION: Tuberculosis in communities and prisons is caused by a variety of MTBC lineages with predominance of local Ethiopian lineages. The increasing prevalence of MDR MTBC strains is alarming. These findings suggest the need for new approaches for control of MDR tuberculosis in Ethiopia.

Efficacy and safety of triple combination therapy with artesunate-amodiaquine-methylene blue for falciparum malaria in children: a randomized controlled trial in Burkina Faso.

BACKGROUND: Methylene blue (MB) has been shown to be safe and effective against falciparum malaria in Africa and to have pronounced gametocytocidal properties. METHODS: Three days of treatment with artesunate (AS)-amodiaquine (AQ) combined with MB was compared with AS-AQ treatment in a randomized controlled phase IIb study; the study included 221 children aged 6-59 months with uncomplicated falciparum malaria in Burkina Faso. The primary end point was gametocyte prevalence during follow-up, as determined by microscopy and real-time quantitative nucleic acid sequence-based amplification (QT-NASBA). RESULTS: The gametocyte prevalence of Plasmodium falciparum at baseline was 3.6% (microscopy) and 97% (QT-NASBA). It was significantly lower in the AS-AQ-MB than in the AS-AQ group on day 7 of follow-up (microscopy, 1.2% vs 8.9% [P < .05]; QT-NASBA, 36.7% vs 63.3% [P < .001]). Hemoglobin values were significantly lower in the AS-AQ-MB group than in the AS-AQ group at days 2 and 7 of follow-up. Vomiting of the study medication occurred significantly more frequently in the AS-AQ-MB group. CONCLUSIONS: The combination of MB with an artemisinin-based combination therapy has been confirmed to be effective against the gametocytes of P. falciparum. MB-based combinations need to be compared with primaquine-based combinations, preferably using MB in an improved pediatric formulation. Clinical Trials Registration: NCT01407887.

Molecular markers of anti-malarial drug resistance in southwest Ethiopia over time: regional surveillance from 2006 to 2013.

BACKGROUND: Drug resistance is one of the main reasons of anti-malarial treatment failures and impedes malaria containment strategies. As single nucleotide polymorphisms (SNPs) have been found to correlate with anti-malarial drug resistance, the surveillance strategy includes continuous monitoring of known molecular markers and detection of new mutation patterns. With the introduction of artemisinin-based combination therapy, selection of specific patterns has been observed worldwide. METHODS: From March to June 2013, whole blood was collected on filter paper from microscopically malaria positive patients in Jimma zone (District), southwestern Ethiopia. Plasmodium falciparum, Plasmodium vivax and mixed infections were included. SNPs were investigated by conventional or real-time PCR, restriction fragment length pattern analysis or sequencing. Results were compared to molecular patterns from Ethiopian isolates in 2004, 2006 and 2008/9. RESULTS: Plasmodium falciparum, P. vivax, and mixed infections were molecularly confirmed in 177, 80, and 14 samples, respectively. In P. falciparum, mutations in the pfcrt, pfmdr 1and pfATP 6 (SERCA) gene were investigated. Whereas the mutation in the pfcrt gene at codon 76 K was still found in 95.6% of all samples, the pfmdr 1 86 T mutation fell to 1.2% (2/163) in 2013 compared to 9% in 2008/9 and 86% in 2006 (P<0.001). The pfmdr 1 184 F mutation dominated with 100.0% (172/172) in 2013. Sequencing of the recently reported PF3D7_1343700 kelch propeller domain showed no mutation at codon 476. First sequencing data of the pvmdr 1 gene from Jimma region revealed a prevalence of the mutations 976 F and 1076 L in 72.7% (16/23) and 100.0% (19/19) of the isolates, respectively. CONCLUSION: Since the introduction of artemether-lumefantrine (AL) in Jimma, Ethiopia, in 2006, the prevalence of certain SNPs associated with AL use has increased. Markers for chloroquine resistance in P. vivax were highly frequent. Continuous molecular and clinical surveillance are of paramount importance.

Efficient quantification and characterization of bacterial outer membrane derived nano-particles with flow cytometric analysis.

There currently exists no efficient and easy method for size profiling and counting of membranous nano-scale particles, such as bacterial outer membrane vesicles (OMVs). We present here a cost-effective and fast method capable of profiling and counting small sample volumes of nano-scale membranous vesicles with standard laboratory equipment without the need for any washing steps. OMV populations of different bacterial species are compared and even subpopulations of OMVs can be identified after a simple labelling procedure. Counting is possible over three orders of magnitude without any changes to the protocol. Protein contaminations do not alter the described measurements.