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1.
Viruses ; 14(6)2022 May 27.
Article in English | MEDLINE | ID: covidwho-1869821

ABSTRACT

Herein, we provide results from a prospective population-based longitudinal follow-up (FU) SARS-CoV-2 serosurveillance study in Tirschenreuth, the county which was hit hardest in Germany in spring 2020 and early 2021. Of 4203 individuals aged 14 years or older enrolled at baseline (BL, June 2020), 3546 participated at FU1 (November 2020) and 3391 at FU2 (April 2021). Key metrics comprising standardized seroprevalence, surveillance detection ratio (SDR), infection fatality ratio (IFR) and success of the vaccination campaign were derived using the Roche N- and S-Elecsys anti-SARS-CoV-2 test together with a self-administered questionnaire. N-seropositivity at BL was 9.2% (1st wave). While we observed a low new seropositivity between BL and FU1 (0.9%), the combined 2nd and 3rd wave accounted for 6.1% new N-seropositives between FU1 and FU2 (ever seropositives at FU2: 15.4%). The SDR decreased from 5.4 (BL) to 1.1 (FU2) highlighting the success of massively increased testing in the population. The IFR based on a combination of serology and registration data resulted in 3.3% between November 2020 and April 2021 compared to 2.3% until June 2020. Although IFRs were consistently higher at FU2 compared to BL across age-groups, highest among individuals aged 70+ (18.3% versus 10.7%, respectively), observed differences were within statistical uncertainty bounds. While municipalities with senior care homes showed a higher IFR at BL (3.0% with senior care home vs. 0.7% w/o), this effect diminished at FU2 (3.4% vs. 2.9%). In April 2021 (FU2), vaccination rate in the elderly was high (>77.4%, age-group 80+).

2.
Vaccines (Basel) ; 10(2)2022 Feb 18.
Article in English | MEDLINE | ID: covidwho-1702407

ABSTRACT

To assess vaccine immunogenicity in non-infected and previously infected individuals in a real-world scenario, SARS-CoV-2 antibody responses were determined during follow-up 2 (April 2021) of the population-based Tirschenreuth COVID-19 cohort study comprising 3378 inhabitants of the Tirschenreuth county aged 14 years or older. Seronegative participants vaccinated once with Vaxzevria, Comirnaty, or Spikevax had median neutralizing antibody titers ranging from ID50 = 25 to 75. Individuals with two immunizations with Comirnaty or Spikevax had higher median ID50s (of 253 and 554, respectively). Regression analysis indicated that both increased age and increased time since vaccination independently decreased RBD binding and neutralizing antibody levels. Unvaccinated participants with detectable N-antibodies at baseline (June 2020) revealed a median ID50 of 72 at the April 2021 follow-up. Previously infected participants that received one dose of Vaxzevria or Comirnaty had median ID50 to 929 and 2502, respectively. Individuals with a second dose of Comirnaty given in a three-week interval after the first dose did not have higher median antibody levels than individuals with one dose. Prior infection also primed for high systemic IgA levels in response to one dose of Comirnaty that exceeded IgA levels observed after two doses of Comirnaty in previously uninfected participants. Neutralizing antibody levels targeting the spike protein of Beta and Delta variants were diminished compared to the wild type in vaccinated and infected participants.

3.
Med Klin Intensivmed Notfmed ; 2022 Jan 03.
Article in German | MEDLINE | ID: covidwho-1603177

ABSTRACT

BACKGROUND: Healthcare workers caring for coronavirus disease 2019 (COVID­19) patients are at an increased risk for a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The aim of this seroepidemiological study was to evaluate the risk of infection for employees at a tertiary care hospital. METHODS: Serological tests for antibodies against SARS-CoV­2 were carried out in a prospective cohort of employees directly involved in the care of COVID­19 patients every 2 weeks from March to July 2020 (1st wave). Antibody status was examined again between December 2020 and February 2021 (2nd wave). RESULTS: The seroprevalence of antibodies against SARS-CoV­2 was 5.1% at the end of the study in February 2021. The cumulative incidence was 3.9% after a median observation period of 261 days. CONCLUSION: We observed a low risk of SARS-CoV­2 infection comparable to that of the general population in the examined cohort of healthcare workers involved in the acute care of COVID­19 patients under the applied hygiene and protective measures.

4.
J Clin Med ; 10(8)2021 Apr 08.
Article in English | MEDLINE | ID: covidwho-1526826

ABSTRACT

Serological testing is crucial in detection of previous infection and in monitoring convalescent and vaccine-induced immunity. During the Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2) pandemic, numerous assay platforms have been developed and marketed for clinical use. Several studies recently compared clinical performance of a limited number of serological tests, but broad comparative evaluation is currently missing. Within this study, a panel of 161 sera from SARS-CoV-2 infected, seasonal CoV-infected and SARS-CoV-2 naïve subjects was enrolled to evaluate 16 ELISA/ECLIA-based and 16 LFA-based tests. Specificities of all ELISA/ECLIA-based assays were acceptable and generally in agreement with the providers' specifications, but sensitivities were lower as specified. Results of the LFAs were less accurate as compared to the ELISAs, albeit with some exceptions. We found a sporadic unequal immune response for different antigens and thus recommend the use of a nucleocapsid protein (N)- and spike protein (S)-based test combination when maximal sensitivity is necessary. Finally, the quality of the immune response in terms of neutralization should be tested using S-based IgG tests.

5.
J Clin Invest ; 131(22)2021 11 15.
Article in English | MEDLINE | ID: covidwho-1518200

ABSTRACT

Metabolic pathways regulate immune responses and disrupted metabolism leads to immune dysfunction and disease. Coronavirus disease 2019 (COVID-19) is driven by imbalanced immune responses, yet the role of immunometabolism in COVID-19 pathogenesis remains unclear. By investigating 87 patients with confirmed SARS-CoV-2 infection, 6 critically ill non-COVID-19 patients, and 47 uninfected controls, we found an immunometabolic dysregulation in patients with progressed COVID-19. Specifically, T cells, monocytes, and granulocytes exhibited increased mitochondrial mass, yet only T cells accumulated intracellular reactive oxygen species (ROS), were metabolically quiescent, and showed a disrupted mitochondrial architecture. During recovery, T cell ROS decreased to match the uninfected controls. Transcriptionally, T cells from severe/critical COVID-19 patients showed an induction of ROS-responsive genes as well as genes related to mitochondrial function and the basigin network. Basigin (CD147) ligands cyclophilin A and the SARS-CoV-2 spike protein triggered ROS production in T cells in vitro. In line with this, only PCR-positive patients showed increased ROS levels. Dexamethasone treatment resulted in a downregulation of ROS in vitro and T cells from dexamethasone-treated patients exhibited low ROS and basigin levels. This was reflected by changes in the transcriptional landscape. Our findings provide evidence of an immunometabolic dysregulation in COVID-19 that can be mitigated by dexamethasone treatment.


Subject(s)
Basigin/physiology , COVID-19/immunology , Dexamethasone/pharmacology , SARS-CoV-2 , T-Lymphocytes/metabolism , Adult , COVID-19/metabolism , Cyclophilin A/physiology , Fatty Acids/metabolism , Female , Humans , Male , Middle Aged , Mitochondria/pathology , Reactive Oxygen Species/metabolism
6.
Diagnostics (Basel) ; 11(10)2021 Oct 06.
Article in English | MEDLINE | ID: covidwho-1463578

ABSTRACT

Antibody testing for determining the SARS-CoV-2 serostatus was rapidly introduced in early 2020 and since then has been gaining special emphasis regarding correlates of protection. With limited access to representative samples with known SARS-CoV-2 infection status during the initial period of test development and validation, spectrum bias has to be considered when moving from a "test establishment setting" to population-based settings, in which antibody testing is currently implemented. To provide insights into the presence and magnitude of spectrum bias and to estimate performance measures of antibody testing in a population-based environment, we compared SARS-CoV-2 neutralization to a battery of serological tests and latent class analyses (LCA) in a subgroup (n = 856) of the larger population based TiKoCo-19 cohort (n = 4185). Regarding spectrum bias, we could proof notable differences in test sensitivities and specificities when moving to a population-based setting, with larger effects visible in earlier registered tests. While in the population-based setting the two Roche ELECSYS anti-SARS-CoV-2 tests outperformed every other test and even LCA regarding sensitivity and specificity in dichotomous testing, they didn't provide satisfying quantitative correlation with neutralization capacity. In contrast, our in-house anti SARS-CoV-2-Spike receptor binding domain (RBD) IgG-ELISA (enzyme-linked-immunosorbant assay) though inferior in dichotomous testing, provided satisfactory quantitative correlation and may thus represent a better correlate of protection. In summary, all tests, led by the two Roche tests, provided sufficient accuracy for dichotomous identification of neutralizing sera, with increasing spectrum bias visible in earlier registered tests, while the majority of tests, except the RBD-ELISA, didn't provide satisfactory quantitative correlations.

7.
Viruses ; 13(6)2021 06 10.
Article in English | MEDLINE | ID: covidwho-1264531

ABSTRACT

SARS-CoV-2 infection fatality ratios (IFR) remain controversially discussed with implications for political measures. The German county of Tirschenreuth suffered a severe SARS-CoV-2 outbreak in spring 2020, with particularly high case fatality ratio (CFR). To estimate seroprevalence, underreported infections, and IFR for the Tirschenreuth population aged ≥14 years in June/July 2020, we conducted a population-based study including home visits for the elderly, and analyzed 4203 participants for SARS-CoV-2 antibodies via three antibody tests. Latent class analysis yielded 8.6% standardized county-wide seroprevalence, a factor of underreported infections of 5.0, and 2.5% overall IFR. Seroprevalence was two-fold higher among medical workers and one third among current smokers with similar proportions of registered infections. While seroprevalence did not show an age-trend, the factor of underreported infections was 12.2 in the young versus 1.7 for ≥85-year-old. Age-specific IFRs were <0.5% below 60 years of age, 1.0% for age 60-69, and 13.2% for age 70+. Senior care homes accounted for 45% of COVID-19-related deaths, reflected by an IFR of 7.5% among individuals aged 70+ and an overall IFR of 1.4% when excluding senior care home residents from our computation. Our data underscore senior care home infections as key determinant of IFR additionally to age, insufficient targeted testing in the young, and the need for further investigations on behavioral or molecular causes of the fewer infections among current smokers.


Subject(s)
Antibodies, Viral/blood , COVID-19/epidemiology , COVID-19/mortality , Population Surveillance/methods , SARS-CoV-2/immunology , Adolescent , Adult , Aged , Aged, 80 and over , COVID-19/blood , COVID-19/immunology , Female , Germany/epidemiology , Humans , Latent Class Analysis , Male , Middle Aged , Prospective Studies , Seasons , Seroepidemiologic Studies , Surveys and Questionnaires , Young Adult
9.
Nat Commun ; 12(1): 3006, 2021 05 21.
Article in English | MEDLINE | ID: covidwho-1238000

ABSTRACT

Coronavirus disease 2019 (COVID-19) can lead to pneumonia and hyperinflammation. Here we show a sensitive method to measure polyclonal T cell activation by downstream effects on responder cells like basophils, plasmacytoid dendritic cells, monocytes and neutrophils in whole blood. We report a clear T cell hyporeactivity in hospitalized COVID-19 patients that is pronounced in ventilated patients, associated with prolonged virus persistence and reversible with clinical recovery. COVID-19-induced T cell hyporeactivity is T cell extrinsic and caused by plasma components, independent of occasional immunosuppressive medication of the patients. Monocytes respond stronger in males than females and IL-2 partially restores T cell activation. Downstream markers of T cell hyporeactivity are also visible in fresh blood samples of ventilated patients. Based on our data we developed a score to predict fatal outcomes and identify patients that may benefit from strategies to overcome T cell hyporeactivity.


Subject(s)
COVID-19/immunology , Inflammation/immunology , Lymphocyte Activation/immunology , Pneumonia/immunology , SARS-CoV-2/immunology , T-Lymphocytes/immunology , Adult , Aged , Basophils/immunology , COVID-19/virology , Cells, Cultured , Dendritic Cells/immunology , Female , Humans , Male , Middle Aged , Monocytes/immunology , Neutrophils/immunology , SARS-CoV-2/physiology , Young Adult
10.
Int J Infect Dis ; 103: 624-627, 2021 Feb.
Article in English | MEDLINE | ID: covidwho-1065181

ABSTRACT

A 21-year-old woman was hospitalized due to coronavirus disease 2019 (COVID-19)-associated respiratory and hepatic impairment concomitant with severe hemolytic anemia. Upon diagnosis of secondary hemophagocytic lymphohistiocytosis, immunosuppression with anakinra and steroids was started, leading to a hepatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and viremia. Subsequent liver biopsy revealed virus particles in hepatocytes by electron microscopy and SARS-CoV-2 virus could be isolated and cultured. Immunosuppression was stopped and convalescent donor plasma given. In the differential diagnosis, an acute crisis of Wilson's disease was raised by laboratory and genetic testing. This case highlights the complexity of balancing immunosuppression to control hyperinflammation versus systemic SARS-CoV-2 dissemination.


Subject(s)
COVID-19/complications , Hepatolenticular Degeneration/diagnosis , Liver/virology , Lymphohistiocytosis, Hemophagocytic/etiology , SARS-CoV-2 , Diagnosis, Differential , Female , Humans , Lymphohistiocytosis, Hemophagocytic/diagnosis , Young Adult
11.
Infection ; 49(1): 75-82, 2021 Feb.
Article in English | MEDLINE | ID: covidwho-725312

ABSTRACT

OBJECTIVE: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic challenges national health systems and the global economy. Monitoring of infection rates and seroprevalence can guide public health measures to combat the pandemic. This depends on reliable tests on active and former infections. Here, we set out to develop and validate a specific and sensitive enzyme linked immunosorbent assay (ELISA) for detection of anti-SARS-CoV-2 antibody levels. METHODS: In our ELISA, we used SARS-CoV-2 receptor-binding domain (RBD) and a stabilized version of the spike (S) ectodomain as antigens. We assessed sera from patients infected with seasonal coronaviruses, SARS-CoV-2 and controls. We determined and monitored IgM-, IgA- and IgG-antibody responses towards these antigens. In addition, for a panel of 22 sera, virus neutralization and ELISA parameters were measured and correlated. RESULTS: The RBD-based ELISA detected SARS-CoV-2-directed antibodies, did not cross-react with seasonal coronavirus antibodies and correlated with virus neutralization (R2 = 0.89). Seroconversion started at 5 days after symptom onset and led to robust antibody levels at 10 days after symptom onset. We demonstrate high specificity (99.3%; N = 1000) and sensitivity (92% for IgA, 96% for IgG and 98% for IgM; > 10 days after PCR-proven infection; N = 53) in serum. CONCLUSIONS: With the described RBD-based ELISA protocol, we provide a reliable test for seroepidemiological surveys. Due to high specificity and strong correlation with virus neutralization, the RBD ELISA holds great potential to become a preferred tool to assess thresholds of protective immunity after infection and vaccination.


Subject(s)
Antibodies, Viral/blood , Antigens, Viral/immunology , COVID-19/diagnosis , Enzyme-Linked Immunosorbent Assay/standards , Neutralization Tests/standards , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Antibodies, Neutralizing/blood , Antigens, Viral/chemistry , COVID-19/blood , COVID-19/immunology , COVID-19/virology , Cross-Sectional Studies , Humans , Immune Sera/chemistry , Immunoglobulin A/blood , Immunoglobulin G/blood , Immunoglobulin M/blood , Protein Domains , Sensitivity and Specificity , Spike Glycoprotein, Coronavirus/chemistry
12.
EJHaem ; 2020 Jun 29.
Article in English | MEDLINE | ID: covidwho-629713

ABSTRACT

The clinical course of coronavirus disease 2019 (COVID-19) varies from mild symptoms to acute respiratory distress syndrome, hyperinflammation, and coagulation disorder. The hematopoietic system plays a critical role in the observed hyperinflammation, particularly in severely ill patients. We conducted a prospective diagnostic study performing a blood differential analyzing morphologic changes in peripheral blood of COVID-19 patients. COVID-19 associated morphologic changes were defined in a training cohort and subsequently validated in a second cohort (n = 45). Morphologic aberrations were further analyzed by electron microscopy (EM) and flow cytometry of lymphocytes was performed. We included 45 COVID-19 patients in our study (median age 58 years; 82% on intensive care unit). The blood differential showed a specific pattern of pronounced multi-lineage aberrations in lymphocytes (80%) and monocytes (91%) of patients. Overall, 84%, 98%, and 98% exhibited aberrations in granulopoiesis, erythropoiesis, and thrombopoiesis, respectively. Electron microscopy revealed the ultrastructural equivalents of the observed changes and confirmed the multi-lineage aberrations already seen by light microscopy. The morphologic pattern caused by COVID-19 is characteristic and underlines the serious perturbation of the hematopoietic system. We defined a hematologic COVID-19 pattern to facilitate further independent diagnostic analysis and to investigate the impact on the hematologic system during the clinical course of COVID-19 patients.

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