Disease severity in hospitalized COVID-19 patients: comparing routine surveillance with cohort data from the LEOSS study in 2020 in Germany

Introduction Studies investigating risk factors for severe COVID-19 often lack information on the representativeness of the study population. Here, we investigate factors associated with severe COVID-19 and compare the representativeness of the dataset to the general population. Methods We used data from the Lean European Open Survey on SARS-CoV-2 infected patients (LEOSS) of hospitalized COVID-19 patients diagnosed in 2020 in Germany to identify associated factors for severe COVID-19, defined as progressing to a critical disease stage or death. To assess the representativeness, we compared the LEOSS cohort to cases of hospitalized patients in the German statutory notification data of the same time period. Descriptive methods and Poisson regression models were used. Results Overall, 6672 hospitalized patients from LEOSS and 132,943 hospitalized cases from the German statutory notification data were included. In LEOSS, patients above 76 years were less likely represented (34.3% vs. 44.1%). Moreover, mortality was lower (14.3% vs. 21.5%) especially among age groups above 66 years. Factors associated with a severe COVID-19 disease course in LEOSS included increasing age, male sex (adjusted risk ratio (aRR) 1.69, 95% confidence interval (CI) 1.53–1.86), prior stem cell transplantation (aRR 2.27, 95% CI 1.53–3.38), and an elevated C-reactive protein at day of diagnosis (aRR 2.30, 95% CI 2.03–2.62). Conclusion We identified a broad range of factors associated with severe COVID-19 progression. However, the results may be less applicable for persons above 66 years since they experienced lower mortality in the LEOSS dataset compared to the statutory notification data.Peer Reviewe

An Advanced Method to Assess the Diet of Free-Ranging Large Carnivores Based on Scats

<div><h3>Background</h3><p>The diet of free-ranging carnivores is an important part of their ecology. It is often determined from prey remains in scats. In many cases, scat analyses are the most efficient method but they require correction for potential biases. When the diet is expressed as proportions of consumed mass of each prey species, the consumed prey mass to excrete one scat needs to be determined and corrected for prey body mass because the proportion of digestible to indigestible matter increases with prey body mass. Prey body mass can be corrected for by conducting feeding experiments using prey of various body masses and fitting a regression between consumed prey mass to excrete one scat and prey body mass (correction factor 1). When the diet is expressed as proportions of consumed individuals of each prey species and includes prey animals not completely consumed, the actual mass of each prey consumed by the carnivore needs to be controlled for (correction factor 2). No previous study controlled for this second bias.</p> <h3>Methodology/Principal Findings</h3><p>Here we use an extended series of feeding experiments on a large carnivore, the cheetah (<em>Acinonyx jubatus</em>), to establish both correction factors. In contrast to previous studies which fitted a linear regression for correction factor 1, we fitted a biologically more meaningful exponential regression model where the consumed prey mass to excrete one scat reaches an asymptote at large prey sizes. Using our protocol, we also derive correction factor 1 and 2 for other carnivore species and apply them to published studies. We show that the new method increases the number and proportion of consumed individuals in the diet for large prey animals compared to the conventional method.</p> <h3>Conclusion/Significance</h3><p>Our results have important implications for the interpretation of scat-based studies in feeding ecology and the resolution of human-wildlife conflicts for the conservation of large carnivores.</p> </div

Hemolysis Is Associated with Low Reticulocyte Production Index and Predicts Blood Transfusion in Severe Malarial Anemia

Background: Falciparum Malaria, an infectious disease caused by the apicomplexan parasite Plasmodium falciparum, is among the leading causes of death and morbidity attributable to infectious diseases worldwide. In Gabon, Central Africa, one out of four inpatients have severe malarial anemia (SMA), a life-threatening complication if left untreated. Emerging drug resistant parasites might aggravate the situation. This case control study investigates biomarkers of enhanced hemolysis in hospitalized children with either SMA or mild malaria (MM). Methods and Findings: Ninety-one children were included, thereof 39 SMA patients. Strict inclusion criteria were chosen to exclude other causes of anemia. At diagnosis, erythrophagocytosis (a direct marker for extravascular hemolysis, EVH) was enhanced in SMA compared to MM patients (5.0 arbitrary units (AU) (interquartile range (IR): 2.2–9.6) vs. 2.1 AU (IR: 1.3–3.9), p<0.01). Furthermore, indirect markers for EVH, (i.e. serum neopterin levels, spleen size enlargement and monocyte pigment) were significantly increased in SMA patients. Markers for erythrocyte ageing, such as CD35 (complement receptor 1), CD55 (decay acceleration factor) and phosphatidylserine exposure (annexin-V-binding) were investigated by flow cytometry. In SMA patients, levels of CD35 and CD55 on the red blood cell surface were decreased and erythrocyte removal markers were increased when compared to MM or reconvalescent patients. Additionally, intravascular hemolysis (IVH) was quantified using several indirect markers (LDH, alpha-HBDH, haptoglobin and hemopexin), which all showed elevated IVH in SMA. The presence of both IVH and EVH predicted the need for blood transfusion during antimalarial treatment (odds ratio 61.5, 95% confidence interval (CI): 8.9–427). Interestingly, this subpopulation is characterized by a significantly lowered reticulocyte production index (RPI, p<0.05). Conclusions: Our results show the multifactorial pathophysiology of SMA, whereby EVH and IVH play a particularly important role. We propose a model where removal of infected and non-infected erythrocytes of all ages (including reticulocytes) by EVH and IVH is a main mechanism of SMA. Further studies are underway to investigate the mechanism and extent of reticulocyte removal to identify possible interventions to reduce the risk of SMA development

Transkriptionelle Regulation der Erythropoese bei der schweren Malariaanämie infolge P. falciparum-Infektion

Die schwere Malariaanämie stellt in endemischen Ländern bei Kindern bis 5 Jahren mit P. falciparum-Infektionen eine der Hauptkomplikationen mit hoher Mortalitätsrate dar. Ein besseres Verständnis der pathophysiologischen Mechanismen, mit denen P. falciparum die schwere Malariaanämie auslöst, ist eine unausweichliche Vorbedingung zur Ergreifung geeigneter Gegenmaßen. Ziel dieser Arbeit war die Untersuchung der Genexpression der mononukleären Knochenmarkzellen von Kindern im Alter von 1 bis 6 Jahren mit schwerer Malariaanämie infolge einer P. falciparum-Infektion und ihren altersgleichen Kontrollgruppen. Dabei sollte die Regulation von Genen der Erythropoese in der Akutphase der Erkrankung und der Rekonvaleszenz verglichen werden. Darüber hinaus sollten Malariapatienten mit schwerer Anämie jenen ohne Anämie gegenüber gestellt werden. Dazu wurden genomweite Expressionsanalysen mittels Oligonukleotidarrays im Knochenmark der Studienpatienten durchgeführt. Eine Auswahl von differentiell exprimierten, Erythropoese-relevanten Genen wurde anschließend mittels Real Time PCR des gesamten Probenkollektivs validiert und quantifiziert. Die Auswertung der klinischen und laborchemischen Daten zeigte ein homogenes Bild der drei Patientengruppen, die sich nur hinsichtlich der zur Gruppenbildung herangezogenen Anämieparameter, des Laktatwertes, MODS-Score und der Milzgröße unterschieden. Der einheitliche Parasitämieverlauf belegte eindrucksvoll, dass die unterschiedlichen Anämiegrade der drei Gruppen nicht auf verschieden hohen Parasitämien beruhen. Die Daten suggerierten das Vorliegen einer Störung der Erythropoese unter Krankheitseinwirkung, die nach der Parasitenelimination einen zeitlich verzögerten, kompensatorischen Anstieg der Retikulozyten und CD71-positiven Zellen mit darauf folgendem Hämoglobinanstieg nach sich zieht. Mithilfe der Ingenuity Pathway Analyse der Mikroarraydaten und einschlägigen Literatur wurden 14 Erythropoese-relevante Kandidatengene ausgewählt, wovon 11 bei der Validierung mittels Real Time PCR ein eindeutig höheres Expressionsniveau in der Gruppe A der schwer anämischen Patienten zeigten. Im Rahmen der untersuchten Genauswahl ließ sich somit keine Störung der Erythropoese auf Transkriptionsebene feststellen. Ob andere Gene eine pathophysiologisch bedeutsame Rolle spielen, müssen weitergehende Untersuchungen zeigen.Severe malarial anaemia is one of the main complications of P. falciparum infections in children under the age of five in endemic countries and involves a high mortality rate. An improved understanding of the pathophysiological mechanisms underlying severe malarial anaemia provoked by P. falciparum is a necessary prerequisite to taking adequate counteractive measures. The objective of this thesis was to analyze the gene expression profile of mononuclear bone marrow cells of children aged 1 to 6 years with severe malarial anaemia due to P. falciparum-infection and their age-matched controls. In doing so, the regulation of genes involved in erythropoiesis in the acute phase of disease was to be compared with the reconvalescent phase. Furthermore, malaria patients with severe anaemia were to be contrasted with those without anaemia. For this purpose, genome-wide expression profiling with oligonucleotide arrays was performed on bone marrow of study patients. A selection of differentially expressed erythropoiesis relevant genes was subsequently validated and quantified by real time PCR of the entire study set. The analysis of the clinical and laboratory data revealed a homogenous composition of the three study groups that only differed in lactate levels, MODS score, splenic size and the haematological variables utilized for group classification. The uniform trends in parasitaemia strikingly demonstrated that the varied grades of anaemia in the three study groups are not based on different levels of parasitaemia. The data set suggests a malfunctioning of erythropoiesis under the influence of disease which entails a delayed compensatory increase in reticulocytes and CD71 positive cells after parasite elimination as well as a subsequent rise in haemoglobin. By conducting an Ingenuity Pathway Analysis of the microarray data and an extensive literature search, 14 erythropoiesis relevant genes were selected of which 11 revealed distinctly higher expression levels in group A of severely anaemic patients when validated by real time PCR. Thus, within the selection of genes analyzed no malfunctioning in erythropoiesis could be detected on the level of transcription. Whether other genes play a pathophysiologically significant role must be shown by further investigations

Letter to the editor: Wide indication for SARS-CoV-2-testing allowed identification of international risk areas during the early phase of the COVID-19 pandemic in Germany

Peer Reviewe

Metagenomic sequencing complements routine diagnostics in identifying viral pathogens in lung transplant recipients with unknown etiology of respiratory infection

BACKGROUND: Lung transplant patients are a vulnerable group of immunosuppressed patients that are prone to frequent respiratory infections. We studied 60 episodes of respiratory symptoms in 71 lung transplant patients. Almost half of these episodes were of unknown infectious etiology despite extensive routine diagnostic testing. METHODS: We re-analyzed respiratory samples of all episodes with undetermined etiology in order to detect potential viral pathogens missed/not accounted for in routine diagnostics. Respiratory samples were enriched for viruses by filtration and nuclease digestion, whole nucleic acids extracted and randomly amplified before high throughput metagenomic virus sequencing. Viruses were identified by a bioinformatic pipeline and confirmed and quantified using specific real-time PCR. RESULTS: In completion of routine diagnostics, we identified and confirmed a viral etiology of infection by our metagenomic approach in four patients (three Rhinovirus A, one Rhinovirus B infection) despite initial negative results in specific multiplex PCR. Notably, the majority of samples were also positive for Torque teno virus (TTV) and Human Herpesvirus 7 (HHV-7). While TTV viral loads increased with immunosuppression in both throat swabs and blood samples, HHV-7 remained at low levels throughout the observation period and was restricted to the respiratory tract. CONCLUSION: This study highlights the potential of metagenomic sequencing for virus diagnostics in cases with previously unknown etiology of infection and in complex diagnostic situations such as in immunocompromised hosts

Measures to cope with the COVID-19 pandemic in Germany: nonpharmaceutical and pharmaceutical interventions

Beim ersten Auftreten des Erregers SARS-CoV‑2 im Dezember 2019 standen weder spezifische therapeutische Möglichkeiten noch ein Impfstoff zur Verfügung. Auch in Deutschland rückten deshalb nichtpharmakologische Maßnahmen zur Kontrolle der COVID-19-Pandemie in den Vordergrund. Am Robert Koch-Institut wurde eine Multikomponentenstrategie aus bevölkerungsbasierten und individuellen infektionshygienischen Maßnahmen entwickelt, die auf bestehenden Influenzapandemieplänen und generischen Planungen aufbaute. Der Beitrag erläutert die empfohlenen nichtpharmakologischen Maßnahmen und stellt die parallel entwickelten pharmakologischen Ansätze dar. Zu den bevölkerungsbasierten Maßnahmen gehören u. a. allgemeine Kontaktbeschränkungen, die Versorgung mit Materialien für den Infektionsschutz, Veranstaltungsverbote, die Schließung von Bildungseinrichtungen und die Beschränkung des Reiseverkehrs. Zusätzlich sind individuelle infektionshygienische Maßnahmen notwendig: z. B. Einhaltung eines Mindestabstands, Reduktion von Kontakten, Tragen einer Mund-Nasen-Bedeckung sowie Einhaltung von Quarantäne und Isolierung. Die Maßnahmen im Gesundheitswesen bauen auf Empfehlungen der Kommission für Krankenhaushygiene und Infektionsprävention (KRINKO) auf und werden von den Fachgesellschaften spezifiziert und implementiert. Als pharmakologische Maßnahmen stehen mit Stand November 2020 eine antivirale Therapie mit Remdesivir und die Behandlung mit dem Glucocorticoid Dexamethason zur Verfügung. Monoklonale Antikörper sind zu diesem Zeitpunkt noch nicht zugelassen. Die therapeutische Antikoagulation wird empfohlen. Die Empfehlungen werden kontinuierlich an die wachsende Kenntnis der Eigenschaften und Übertragungswege des Erregers angepasst. Eine große Herausforderung besteht darin, das Vertrauen der Bevölkerung in die empfohlenen Maßnahmen zu stärken. Viele Maßnahmen müssen individuell angewandt werden, um gemeinsam zu wirken.When the emerging novel SARS-CoV‑2 virus first appeared in December 2019, neither specific therapeutic options nor vaccinations were available. The role of nonpharmaceutical interventions (NPIs) became of central importance. At the Robert Koch Institute, a multilayer strategy consisting of population-based and individual preventive measures to control the pandemic was developed, which built upon existing influenza pandemic plans as well as generic plans. This paper explains the recommended NPIs and illustrates the pharmaceutical approaches developed in parallel. Among others, general contact bans, providing material for infection prevention and control, ban of events, closing educational institutions, and restricting travel are counted among population-based measures. Additional individual preventive measures are necessary, e.g., keeping a minimum distance, reducing contacts, and wearing a mouth–nose covering as well as quarantine and isolation. Measures within the health system are based on recommendations of the Commission on Hospital Hygiene and Infection Protection (Kommission für Krankenhaushygiene und Infektionsprävention (KRINKO)) and specified and implemented by professional societies. Since November 2020, an antiviral therapy with remdesivir and treatment with the glucocorticoid dexamethasone have been available as pharmaceutical interventions. Monoclonal antibodies are at this time not approved. Therapeutic anticoagulation is recommended. Recommendations are constantly adapted to the increasing knowledge on the pathogen and its means of transmission. A challenge is to strengthen the trust of the population. Many measures have to be applied on an individual basis in order to work together.Peer Reviewe

Abwägung der Dauer von Quarantäne und Isolierung bei COVID-19

Abwägung der Dauer von Quarantäne und Isolierung bei COVID-19 Angesichts weltweit zunehmender Fallzahlen mit SARS-CoV-2 ist die konsequente Einhaltung von Maßnahmen zur Verlangsamung der Ausbreitung erforderlich. Grundlage bildet die AHA+L-Regel. Falls es zu SARS-CoV-2-Infektionen kommt, stehen individuelle Maßnahmen im Vordergrund: eine mindestens 10-tägige (Selbst-)Isolierung von Erkrankten und Personen, bei denen eine Virusausscheidung festgestellt worden ist, und die 14-tägige Quarantäne derjenigen, bei denen nach Kontakt zu einer ansteckenden Person die Wahrscheinlichkeit besteht, dass es zu einer Ansteckung gekommen ist. Im Epidemiologischen Bulletin 39/2020 wird der Unterschied von Quarantäne und Isolierung basierend auf den Grundlagen des Infektionsverlaufs näher erläutert. Erste Ergebnisse aus internen Rechenmodellen des Robert Koch-Instituts verdeutlichen, wie sich das Restrisiko einer Infektion Dritter in Abhängigkeit von der Quarantänedauer mit oder ohne abschließende Testung verhält