Clinical efficacy of SARS-CoV-2 Omicron-neutralizing antibodies in immunoglobulin preparations for the treatment of agammaglobulinemia in patients with primary antibody deficiency.

Immunocompromised individuals are at significantly elevated risk for severe courses of coronavirus disease 2019 (COVID-19). In addition to vaccination, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) neutralizing antibodies (nAbs) have been applied throughout the pandemic, with time of treatment onset and potency against the currently prevailing virus variant identified as relevant factors for medical benefit. Using data from the European Society for Immunodeficiencies (ESID) registry, the present study evaluated COVID-19 cases in three groups of patients with inborn errors of immunity (IEI; 981 agammaglobulinemia patients on immunoglobulin replacement therapy (IGRT); 8960 non-agammaglobulinemia patients on IGRT; 14 428 patients without IGRT), and the neutralizing capacity of 1100 immunoglobulin lots against SARS-CoV-2 ("Wuhan" and Omicron strains), throughout 3 years. From the first (2020/2021) to the second (2021/2022) cold season, i.e., during the virus drift to the more contagious Omicron variants, an increase in case numbers was recorded that was comparable (~2- to 3-fold) for all three study groups. During the same period, immunoglobulin lots showed a profound nAb increase against the archetypal SARS-CoV-2 strain, yet only low levels of Omicron nAbs. Notably, shortly before the third (2022/2023) cold season, Omicron-neutralizing capacity of released immunoglobulin lots had plateaued at high levels. From the second to the third cold season, COVID-19 cases dropped markedly. While a ~6-fold case reduction was recorded for the groups of non-agammaglobulinemia patients on IGRT and IEI patients not receiving IGRT, the decline was ~30-fold for the group of agammaglobulinemia patients on IGRT. These findings suggest a substantial COVID-19-protective effect of IGRT, at least for distinct groups of antibody-deficient patients.

Pre-existing sleep problems as a predictor of post-acute sequelae of COVID-19.

Several months after COVID-19 many individuals still report persisting symptoms, the so-called 'post-COVID-19 syndrome'. An immunological dysfunction is one of the main pathophysiological hypotheses. As sleep is central to the functioning of the immune system, we investigated whether self-reported pre-existing sleep disturbance might be an independent risk factor for the development of post-COVID-19 syndrome. A total of 11,710 participants of a cross-sectional survey (all tested positive for severe acute respiratory syndrome coronavirus-2) were classified into probable post-COVID-19 syndrome, an intermediate group, and unaffected participants at an average of 8.5 months after infection. The case definition was based on newly occurring symptoms of at least moderate severity and ≥20% reduction in health status and/or working capacity. Unadjusted and adjusted odds ratios were calculated to investigate the association between pre-existing sleep disturbances and subsequent development of post-COVID-19 syndrome while controlling for a variety of demographic, lifestyle, and health factors. Pre-existing sleep disturbances were found to be an independent predictor of subsequent probable post-COVID-19 syndrome (adjusted odds ratio 2.7, 95% confidence interval 2.27-3.24). Sleep disturbances as part of the post-COVID-19 syndrome were reported by more than half of the participants and appeared to be a new symptom and to occur independent of a mood disorder in most cases. Recognition of disturbed sleep as an important risk factor for post-COVID-19 syndrome should promote improved clinical management of sleep disorders in the context of COVID-19. Further, it may stimulate further research on the effect of improving sleep on the prognosis of COVID-19 long-term sequelae and other post-viral conditions.

Activated phosphoinositide 3-kinase δ syndrome: Update from the ESID Registry and comparison with other autoimmune-lymphoproliferative inborn errors of immunity.

BACKGROUND: Activated phosphoinositide-3-kinase δ syndrome (APDS) is an inborn error of immunity (IEI) with infection susceptibility and immune dysregulation, clinically overlapping with other conditions. Management depends on disease evolution, but predictors of severe disease are lacking. OBJECTIVES: This study sought to report the extended spectrum of disease manifestations in APDS1 versus APDS2; compare these to CTLA4 deficiency, NFKB1 deficiency, and STAT3 gain-of-function (GOF) disease; and identify predictors of severity in APDS. METHODS: Data was collected from the ESID (European Society for Immunodeficiencies)-APDS registry and was compared with published cohorts of the other IEIs. RESULTS: The analysis of 170 patients with APDS outlines high penetrance and early onset of APDS compared to the other IEIs. The large clinical heterogeneity even in individuals with the same PIK3CD variant E1021K illustrates how poorly the genotype predicts the disease phenotype and course. The high clinical overlap between APDS and the other investigated IEIs suggests relevant pathophysiological convergence of the affected pathways. Preferentially affected organ systems indicate specific pathophysiology: bronchiectasis is typical of APDS1; interstitial lung disease and enteropathy are more common in STAT3 GOF and CTLA4 deficiency. Endocrinopathies are most frequent in STAT3 GOF, but growth impairment is also common, particularly in APDS2. Early clinical presentation is a risk factor for severe disease in APDS. CONCLUSIONS: APDS illustrates how a single genetic variant can result in a diverse autoimmune-lymphoproliferative phenotype. Overlap with other IEIs is substantial. Some specific features distinguish APDS1 from APDS2. Early onset is a risk factor for severe disease course calling for specific treatment studies in younger patients.

The GAIN Registry - a New Prospective Study for Patients with Multi-organ Autoimmunity and Autoinflammation.

Patient registries are a very important and essential tool for investigating rare diseases, as most physicians only see a limited number of cases during their career. Diseases of multi-organ autoimmunity and autoinflammation are especially challenging, as they are characterized by diverse clinical phenotypes and highly variable expressivity. The GAIN consortium (German multi-organ Auto Immunity Network) developed a dataset addressing these challenges. ICD-11, HPO, and ATC codes were incorporated to document various clinical manifestations and medications with a defined terminology. The GAIN dataset comprises detailed information on genetics, phenotypes, medication, and laboratory values. Between November 2019 and July 2022, twelve centers from Europe have registered 419 patients with multi-organ autoimmunity or autoinflammation. The median age at onset of symptoms was 13 years (IQR 3-28) and the median delay from onset to diagnosis was 5 years (IQR 1-14). Of 354 (84.5%) patients who were genetically tested, 248 (59.2%) had a defined monogenetic cause. For 87 (20.8%) patients, no mutation was found and for 19 (4.5%), the result was pending. The most common gene affected was NFkB1 (48, 11.5%), and the second common was CTLA4 (40, 9.5%), both genetic patient groups being fostered by specific research projects within GAIN. The GAIN registry may serve as a valuable resource for research in the inborn error of immunity community by providing a platform for etiological and diagnostic research projects, as well as observational trials on treatment options.

The Human Phenotype Ontology in 2021.

The Human Phenotype Ontology (HPO, https://hpo.jax.org) was launched in 2008 to provide a comprehensive logical standard to describe and computationally analyze phenotypic abnormalities found in human disease. The HPO is now a worldwide standard for phenotype exchange. The HPO has grown steadily since its inception due to considerable contributions from clinical experts and researchers from a diverse range of disciplines. Here, we present recent major extensions of the HPO for neurology, nephrology, immunology, pulmonology, newborn screening, and other areas. For example, the seizure subontology now reflects the International League Against Epilepsy (ILAE) guidelines and these enhancements have already shown clinical validity. We present new efforts to harmonize computational definitions of phenotypic abnormalities across the HPO and multiple phenotype ontologies used for animal models of disease. These efforts will benefit software such as Exomiser by improving the accuracy and scope of cross-species phenotype matching. The computational modeling strategy used by the HPO to define disease entities and phenotypic features and distinguish between them is explained in detail.We also report on recent efforts to translate the HPO into indigenous languages. Finally, we summarize recent advances in the use of HPO in electronic health record systems.

Phenotype, genotype, treatment, and survival outcomes in patients with X-linked inhibitor of apoptosis deficiency.

BACKGROUND: X-linked inhibitor of apoptosis (XIAP) deficiency is a rare primary immunodeficiency disease caused by XIAP gene mutations. A broad range of phenotype, severity, and age at onset present challenges for patient management. OBJECTIVE: We sought to characterize the phenotype, treatment, and survival outcomes of XIAP deficiency and to assess parameters influencing prognosis. METHODS: Data published from 2006 to 2020 were retrospectively analyzed. RESULTS: A total of 167 patients from 117 families with XIAP deficiency were reported with 90 different mutations. A wide spectrum of clinical features were seen, of which hemophagocytic lymphohistiocytosis (HLH) and inflammatory bowel disease were the most common. Patients frequently developed multiple features with no clear genotype-phenotype correlation. A total of 117 patients were managed conservatively and 50 underwent hematopoietic stem-cell transplantation (HSCT), with respective overall survival probabilities of 90% and 53% at age 16 years. The predominant indication for HSCT was early-onset HLH. Active HLH and myeloablative conditioning regimens increased HSCT-related mortality, although HSCT outcome was much better after 2015 than before. For conservatively managed patients reaching adulthood, survival probabilities were 86% at age 30 years and 37% by age 52 years, with worse outcomes for patients developing the disease before the age of 5 years or with new disease features in adulthood. Nine asymptomatic mutation carriers with a median age of 13.5 years were identified. CONCLUSIONS: Our study demonstrates the variable nature of XIAP deficiency, which evolves over life for individual patients. Better therapeutic strategies and prospective studies are required to reduce morbidity and mortality and improve decision making and long-term outcomes for patients with XIAP deficiency.

Inborn Errors of Immunity on the Island of Ireland - a Cross-Jurisdictional UKPID/ESID Registry Report.

The epidemiology of inborn errors of immunity (IEI) in the Republic of Ireland was first published in 2005 but has not been updated since. IEI prevalence data from Northern Ireland was last published in 2018. Using data from the United Kingdom Primary Immune Deficiency (UKPID) and European Society for Immunodeficiencies (ESID) registries, we reviewed all registered cases of IEI affecting adult patients ≥ 18 years of age from the two largest immunology specialist centres in Northern Ireland and the Republic of Ireland, respectively and calculated the combined minimum adult prevalence of IEI on the island of Ireland for the first time. We also recorded data pertaining to presenting symptoms of IEI, diagnostic delay, immunoglobulin data, and genetic testing, as well as briefly reporting data pertaining to secondary immunodeficiency in both countries. As of 1 May 2020, we identified a minimum adult IEI prevalence in Ireland of 8.85/100,000 population.

Evaluation of Laboratory and Sonographic Parameters for Detection of Portal Hypertension in Patients with Common Variable Immunodeficiency.

Timely detection of portal hypertension as a manifestation in a subgroup of patients with common variable immunodeficiency (CVID) represents a challenge since it is usually not associated with liver cirrhosis. To identify relevant markers for portal hypertension, we evaluated clinical history, laboratory parameters, and abdominal ultrasound including liver elastography and biomarkers of extracellular matrix formation. Twenty seven (6%) of 479 CVID patients presented with clinically significant portal hypertension as defined by either the presence of esophageal varices or ascites. This manifestation occurred late during the course of the disease (11.8 years after first diagnosis of CVID) and was typically part of a multiorgan disease and associated with a high mortality (11/27 patients died during follow up). The strongest association with portal hypertension was found for splenomegaly with a longitudinal diameter of > 16 cm. Similarly, most patients presented with a liver stiffness measurement (LSM) of above 6.5 kPa, and a LSM above 20 kPa was always indicative of manifest portal hypertension. Additionally, many laboratory parameters including Pro-C4 were significantly altered in patients with portal hypertension without clearly increasing the discriminatory power to detect non-cirrhotic portal hypertension in CVID. Our data suggest that a spleen size above 16 cm and an elevated liver stiffness above 6.5 kPa should prompt further evaluation of portal hypertension and its sequelae, but earlier and better liquid biomarkers of this serious secondary complication in CVID are needed.

Initial presenting manifestations in 16,486 patients with inborn errors of immunity include infections and noninfectious manifestations.

BACKGROUND: Inborn errors of immunity (IEI) are rare diseases, which makes diagnosis a challenge. A better description of the initial presenting manifestations should improve awareness and avoid diagnostic delay. Although increased infection susceptibility is a well-known initial IEI manifestation, less is known about the frequency of other presenting manifestations. OBJECTIVE: We sought to analyze age-related initial presenting manifestations of IEI including different IEI disease cohorts. METHODS: We analyzed data on 16,486 patients of the European Society for Immunodeficiencies Registry. Patients with autoinflammatory diseases were excluded because of the limited number registered. RESULTS: Overall, 68% of patients initially presented with infections only, 9% with immune dysregulation only, and 9% with a combination of both. Syndromic features were the presenting feature in 12%, 4% had laboratory abnormalities only, 1.5% were diagnosed because of family history only, and 0.8% presented with malignancy. Two-third of patients with IEI presented before the age of 6 years, but a quarter of patients developed initial symptoms only as adults. Immune dysregulation was most frequently recognized as an initial IEI manifestation between age 6 and 25 years, with male predominance until age 10 years, shifting to female predominance after age 40 years. Infections were most prevalent as a first manifestation in patients presenting after age 30 years. CONCLUSIONS: An exclusive focus on infection-centered warning signs would have missed around 25% of patients with IEI who initially present with other manifestations.

Altered Spectrum of Lymphoid Neoplasms in a Single-Center Cohort of Common Variable Immunodeficiency with Immune Dysregulation.

PURPOSE: Common variable immune deficiency (CVID) confers an increased risk of lymphoid neoplasms, but reports describing the precise WHO specification of the lymphoma subtypes and their immunological environment are lacking. We therefore classified lymphomas-occurring in a cohort of 21 adult CVID patients during a 17-year period at our center-according to the 2016 WHO classification and characterized the local and systemic immunological context RESULTS: The median time between the onset of CVID and lymphoma was 14 years. Patients showed a high prevalence of preceding immune dysregulation: lymphadenopathy (n = 13, 62%), splenomegaly (n = 18, 86%), autoimmune cytopenia (n = 14, 67%), and gastrointestinal involvement (n = 15, 71%). The entities comprised extranodal marginal zone lymphoma (n = 6), diffuse large B cell lymphoma (n = 7), plasmablastic lymphoma (n = 1), classic Hodgkin lymphoma (n = 4, including three cases with germline CTLA4 mutations), T cell large granular lymphocytic leukemia (n = 2), and peripheral T cell lymphoma, not otherwise specified (n = 1), but no follicular lymphoma. An Epstein-Barr virus association was documented in eight of 16 investigated lymphomas. High expression of PDL1 by tumor cells in five and of PDL1 and PD1 by tumor-infiltrating macrophages and T cells in 12 of 12 investigated lymphomas suggested a tolerogenic immunological tumor environment. CONCLUSION: In summary, a diverse combination of specific factors like genetic background, chronic immune activation, viral trigger, and impaired immune surveillance contributes to the observed spectrum of lymphomas in CVID. In the future, targeted therapies, e.g., PD1/PDL1 inhibitors in CVID associated lymphomas with a tolerogenic environment may improve therapy outcome.

Incidence of SCID in Germany from 2014 to 2015 an ESPED* Survey on Behalf of the API*** Erhebungseinheit für Seltene Pädiatrische Erkrankungen in Deutschland (German Paediatric Surveillance Unit) ** Arbeitsgemeinschaft Pädiatrische Immunologie.

PURPOSE: Severe combined immunodeficiencies (SCID) are a heterogeneous group of fatal genetic disorders, in which the immune response is severely impaired. SCID can be cured if diagnosed early. We aim to determine the incidence of clinically defined SCID cases, acquire data of reported cases and evaluate their possible prediction by newborn screening, before introduction of a general screening program in Germany. METHODS: The German Surveillance Unit for rare Paediatric Diseases (ESPED) prospectively queried the number of incident SCID cases in all German paediatric hospitals in 2014 and 2015. Inclusion criteria were (1) opportunistic or severe infections or clinical features associated with SCID (failure to thrive, lacking thymus or lymphatic tissue, dysregulation of the immune system, graft versus host reaction caused by maternal T cells), (2) dysfunctional T cell immunity or proof of maternal T cells and (3) exclusion of a secondary immunodeficiency such as human immunodeficiency virus (HIV) infection. In a capture-recapture analysis, cases were matched with cases reported to the European Society for Immunodeficiencies (ESID). RESULTS: Fifty-eight patients were initially reported to ESPED, 24 reports could be confirmed as SCID, 21 patients were less than 1 year old at time of diagnosis. One SCID case was reported to ESID only. The estimated incidence of SCID in Germany is 1.6/100,000 (1:62,500) per year in children less than 1 year of age. Most patients reported were symptomatic and mortality in regard to reported outcome was high (29% (6/22)). The majority of incident SCID cases were considered to be probably detectable by newborn screening. CONCLUSIONS: SCID is a rare disease with significant mortality. Newborn screening may give the opportunity to improve the prognosis in a significant number of children with SCID.

The NEW ESID online database network.

SUMMARY: Primary Immunodeficiencies (PIDs) belong to the group of rare diseases. The European Society for Immunodeficiencies (ESID) operates an international research database application for continuous long-term documentation of patient data. The system is a web application which runs in a standard browser. Therefore, the system is easy to access from any location. Technically, the system is based on Gails backed by MariaDB with high standard security features to comply with the demands of a modern research platform. AVAILABILITY AND IMPLEMENTATION: The ESID Online Database is accessible via the official website: https://esid.org/Working-Parties/Registry-Working-Party/ESID-Registry. A demo system is available via: https://cci-esid-reg-demo-app.uniklinik-freiburg.de/EERS with user demouser and password Demo-2019.

[Patient registries for rare diseases in Germany: concept paper of the NAMSE strategy group]. / Patientenregister für Seltene Erkrankungen in Deutschland: Konzeptpapier der Strategiegruppe "Register" des Nationalen Aktionsbündnisses für Menschen mit Seltenen Erkrankungen (NAMSE).

The National Action Plan for People with Rare Diseases contains 52 concrete actions, including in the fields of care, research, diagnosis, and information management. With the aim of improving the quality and interoperability of national registries in the long term, action 28 proposed the establishment of a "Rare Diseases Registry" strategy group. The strategy group began its work in 2016. In this report, the group takes into account developments at the national and international level in order to develop recommendations for national initiatives.In addition to this, the group reports on consent and implementation as well as on the adaptation of a minimal dataset for use in rare disease registries and mapping the used data elements and schemata in a metadata repository. This position paper was created by the strategy group together with additional authors. The paper reached a consensus within the strategy group and can be seen as a concept paper of the Rare Diseases Registry strategy group.

Evaluating laboratory criteria for combined immunodeficiency in adult patients diagnosed with common variable immunodeficiency.

Some patients diagnosed with common variable immunodeficiency (CVID) actually suffer from combined immunodeficiency (CID) and therefore may require a different, CID-adapted treatment. Several CD4 T-cell-based criteria have been proposed in the past to identify patients with CID within the cohort of adult CVID patients. In this monocentric study, we used retrospective immunological and clinical data of 238 CVID patients to compare four different proposals of how to define CID among CVID patients. We demonstrate that none of the current definitions sufficiently separates CID from CVID patients and that the relative reduction of naïve CD4 T cells <10% has the highest sensitivity of all tested markers for patients with clinical complications often associated with CID. Thus, a very low percentage of naïve CD4 T cells in any adult CVID patient should raise suspicion, but is not sufficient to define CID among CVID patients.

Clinical picture and treatment of 2212 patients with common variable immunodeficiency.

BACKGROUND: Common variable immunodeficiency (CVID) is an antibody deficiency with an equal sex distribution and a high variability in clinical presentation. The main features include respiratory tract infections and their associated complications, enteropathy, autoimmunity, and lymphoproliferative disorders. OBJECTIVE: This study analyzes the clinical presentation, association between clinical features, and differences and effects of immunoglobulin treatment in Europe. METHODS: Data on 2212 patients with CVID from 28 medical centers contributing to the European Society for Immunodeficiencies Database were analyzed retrospectively. RESULTS: Early disease onset (<10 years) was very frequent in our cohort (33.7%), especially in male subjects (39.8%). Male subjects with early-onset CVID were more prone to pneumonia and less prone to other complications suggesting a distinct disease entity. The diagnostic delay of CVID ranges between 4 and 5 years in many countries and is particularly high in subjects with early-onset CVID. Enteropathy, autoimmunity, granulomas, and splenomegaly formed a set of interrelated features, whereas bronchiectasis was not associated with any other clinical feature. Patient survival in this cohort was associated with age at onset and age at diagnosis only. There were different treatment strategies in Europe, with considerable differences in immunoglobulin dosing, ranging from 130 up to 750 mg/kg/mo. Patients with very low trough levels of less than 4 g/L had poor clinical outcomes, whereas higher trough levels were associated with a reduced frequency of serious bacterial infections. CONCLUSION: Patients with CVID are being managed differently throughout Europe, affecting various outcome measures. Clinically, CVID is a truly variable antibody deficiency syndrome.

Post-COVID syndrome and work ability 9-12 months after a SARS-CoV-2 infection among over 9000 employees from the general population.

Objectives: Evidence on the work-related societal impact of long-term health-related consequences following SARS-CoV-2 is emerging. We characterize the modified work ability index (mWAI) of employees 6 to 12 months after an acute infection compared to pre-infection. Methods: Analyses were based on a population-based, multi-center cross-sectional study including employees aged 18-65 years with positive SARS-CoV-2 polymerase chain reaction (tested between October 2020-April 2021 in defined geographic regions in Germany). Prevalences and results of adjusted logistic regression analyses were given. Results: In 9752 employees (mean age 45.6 years, 58% females, response 24%), n = 1217 (13.1%) participants were regarded as having low mWAI compared to pre-infection. Outpatient medical treatment, inpatient treatment, and admission to intensive care during infection were associated with mWAI <15th percentile (P15, each odds ratio [OR] >3.0). Post-COVID symptom clusters most strongly linked to mWAI

Association of BMI with general health, working capacity recovered, and post-acute sequelae of COVID-19.

OBJECTIVE: The aim of this study was to determine the risk of post-acute sequelae of COVID-19 associated with the continuous spectrum of BMI. METHODS: Epidemiology of Long COVID (EPILOC) is a population-based study conducted in Baden-Württemberg (Germany), including subjects aged 18 to 65 years who tested positive for SARS-CoV-2 between October 2020 and April 2021. Eligible subjects answered a standardized questionnaire, including sociodemographic characteristics, lifestyle factors, and the presence of specific symptoms. Participants assessed their current general health recovery and working capacity compared with the pre-infection situation and provided their body height and weight. Generalized additive models were used to assess the association of BMI with general health recovered, working capacity recovered, and prevalence of fatigue, cognitive impairment, and chest symptoms. RESULTS: The analyses included 11,296 individuals (41% male), with a mean age of 44.0 (SD 13.7) years. Best general health recovery was observed at BMI of 22.1 (95% CI: 21.0-27.0) kg/m2 in men and BMI of 21.6 (95% CI: 20.3-23.1) kg/m2 in women. In addition, we found that increasing BMI was consistently associated with post-COVID fatigue, neurocognitive impairment, and chest symptoms. CONCLUSIONS: High BMI contributes to impaired recovery after SARS-CoV-2 infection; however, a low BMI is associated with impaired recovery as well.

Research on Rare Diseases in Germany - The GAIN Registry: a registry for individuals with congenital multi-organ autoimmune diseases.

Background: Patient registries are an important tool for networking medical caregivers and research, especially in the field of rare diseases. Individuals afflicted by multi-organ autoimmune diseases typically suffer from inflammation of multiple organs. Project: GAIN (German genetic multi-organ Auto-Immunity Network) is the German network for research and therapy optimisation for individuals with congenital multi-organ autoimmune diseases. As a sub-project of the network, the registry systematically collects data from this patient group and makes it available for research purposes. Results: A data set was developed and made available for the GAIN Registry that can map the complex clinical status of persons with multi-organ autoimmune diseases. Data from 486 individuals have been documented to date. Conclusions: The GAIN register allows for a very comprehensive documentation that clearly goes beyond previous approaches, e.g. by linking it to biosamples collected in the consortium. The planned inclusion of patients in the documentation, e.g. of data on quality of life, opens up a new field.

Post-acute sequelae of covid-19 six to 12 months after infection: population based study.

OBJECTIVES: To describe symptoms and symptom clusters of post-covid syndrome six to 12 months after acute infection, describe risk factors, and examine the association of symptom clusters with general health and working capacity. DESIGN: Population based, cross sectional study SETTING: Adults aged 18-65 years with confirmed SARS-CoV-2 infection between October 2020 and March 2021 notified to health authorities in four geographically defined regions in southern Germany. PARTICIPANTS: 50 457 patients were invited to participate in the study, of whom 12 053 (24%) responded and 11 710 (58.8% (n=6881) female; mean age 44.1 years; 3.6% (412/11 602) previously admitted with covid-19; mean follow-up time 8.5 months) could be included in the analyses. MAIN OUTCOME MEASURES: Symptom frequencies (six to 12 months after versus before acute infection), symptom severity and clustering, risk factors, and associations with general health recovery and working capacity. RESULTS: The symptom clusters fatigue (37.2% (4213/11 312), 95% confidence interval 36.4% to 38.1%) and neurocognitive impairment (31.3% (3561/11 361), 30.5% to 32.2%) contributed most to reduced health recovery and working capacity, but chest symptoms, anxiety/depression, headache/dizziness, and pain syndromes were also prevalent and relevant for working capacity, with some differences according to sex and age. Considering new symptoms with at least moderate impairment of daily life and ≤80% recovered general health or working capacity, the overall estimate for post-covid syndrome was 28.5% (3289/11 536, 27.7% to 29.3%) among participants or at least 6.5% (3289/50 457) in the infected adult population (assuming that all non-responders had completely recovered). The true value is likely to be between these estimates. CONCLUSIONS: Despite the limitation of a low response rate and possible selection and recall biases, this study suggests a considerable burden of self-reported post-acute symptom clusters and possible sequelae, notably fatigue and neurocognitive impairment, six to 12 months after acute SARS-CoV-2 infection, even among young and middle aged adults after mild infection, with a substantial impact on general health and working capacity. TRIAL REGISTRATION: German registry of clinical studies DRKS 00027012.