Coronavirus disease 2019 in patients with inborn errors of immunity: An international study

A single-center experience of COVID-19 infection in patients with primary immunodeficiency

Background

Reported outcomes in patients with primary immunodeficiency (PID) infected by coronavirus disease 2019 (COVID-19) have been variable owing to a combination of viral strain heterogeneity, differences in patient populations and health systems, and local availability of vaccination and specific COVID-19 therapies. There are few reports on the experience of Australian patients with PID during the pandemic.

Objectives

In this retrospective study, we describe the baseline characteristics and short-term outcomes of patients with PID who were infected by COVID-19 and known to the Royal Melbourne Hospital, a major tertiary center in Victoria, Australia.

Methods

Between April 2021 and April 2022, a total of 31 of 138 patients with PID were affected by COVID-19. More than half of them had 3 vaccine doses at the time of infection (which at the time was considered being fully vaccinated) and received COVID-19-targeted treatment.

Results

All of the infected patients had ambulatory disease, with no cases of morbidity or mortality. In line with the current literature, the PID subtypes described did not appear to independently predict worse outcomes.

Conclusions

Some protective factors include this cohort's relatively younger average age and its high uptake of vaccination and COVID-19 therapies.

The Effect of Pulmonary Hypertension on Mortality and Intensive Care Unit Admission in Patients With SARS-CoV-2 Infection: A Systematic Review and Meta-Analysis

AIM

Severe COVID-19 can cause acute respiratory distress syndrome, hypoxia, systemic complications, and increased mortality. Pulmonary hypertension (PH) is a major global health issue associated with worsening symptoms and increased mortality. This systematic review aimed to assess the influence of PH onset among COVID-19 patients on all-cause mortality and intensive care unit (ICU) admission.

METHOD

An unrestricted search of five databases up to June 2022 was undertaken. Pulmonary hypertension was assessed using transthoracic echocardiogram, computed tomography, or right heart catheterisation. After duplicate screening, data extraction, and risk of bias assessment, random effects meta-analyses of odds ratios (OR) and their 95% confidence intervals (CI) were performed for all-cause mortality and ICU admission.

RESULTS

From the 26 studies that were included (3,373 patients, 76% males, median age 62.6 years), PH in COVID-19 patients was significantly associated with higher odds for all-cause mortality (26 studies; OR 3.89; 95% CI 2.85-5.31; p<0.001) and higher odds for ICU admission (six studies; OR 2.50; 95% CI 1.69-3.70; p<0.001). Meta-regression/subgroup analyses by patient demographics, comorbidities, or therapeutic regimens, and sensitivity analyses did not find any differences.

CONCLUSION

Evidence from observational studies indicates that PH in COVID-19 patients is associated with increased odds of mortality and ICU admission.

Lack of Specific Immune Response after Five Doses of mRNA SARS-CoV-2 Vaccine in a Patient with CD4+ T-Cell Lymphopenia but Preserved Responses to CMV

Immunogenicity of SARS-CoV-2 mRNA vaccines is highly heterogeneous in patients with inborn errors of immunity (IEIs). This case report analyzes the immune response to mRNA COVID-19 two-dose primary vaccination followed by three boosters in an IEI patient with marked CD4+ T-cell cytopenia and diminished thymic output, in comparison with that raised against latent, chronic cytomegalovirus (CMV) infection. Serum IgG antibodies anti-spike (S) protein of SARS-CoV-2 and anti-CMV were both determined by chemiluminescent microparticle immunoassays (CMIAs). SARS-CoV-2 and CMV memory CD4+ T-cell responses were simultaneously evaluated in vitro using an activation-induced marker (AIM) assay via multicolor flow cytometry. Throughout the 2-year follow-up that included the administration of five doses of SARS-CoV-2 mRNA vaccines, cellular anti-SARS-CoV-2-specific responses remained consistently negative, with extremely weak humoral responses, while the patient showed in vitro persistent CD4+ T-cell reactivity to CMV peptides and high-IgG CMV-specific titers. The assessment of immune responses to vaccines and prevalent viruses is essential in IEI patients in order to take adequate preventive measures.

COVID-19 Vaccination in Patients with Inborn Errors of Immunity Reduces Hospitalization and Critical Care Needs Related to COVID-19: a USIDNET Report

BACKGROUND

The CDC and ACIP recommend COVID-19 vaccination for patients with inborn errors of immunity (IEI). Not much is known about vaccine safety in IEI, and whether vaccination attenuates infection severity in IEI.

OBJECTIVE

To estimate COVID-19 vaccination safety and examine effect on outcomes in patients with IEI.

METHODS

We built a secure registry database in conjunction with the US Immunodeficiency Network to examine vaccination frequency and indicators of safety and effectiveness in IEI patients. The registry opened on January 1, 2022, and closed on August 19, 2022.

RESULTS

Physicians entered data on 1245 patients from 24 countries. The most common diagnoses were antibody deficiencies (63.7%). At least one COVID-19 vaccine was administered to 806 patients (64.7%), and 216 patients received vaccination prior to the development of COVID-19. The most common vaccines administered were mRNA-based (84.0%). Seventeen patients were reported to seek outpatient clinic or emergency room care for a vaccine-related complication, and one patient was hospitalized for symptomatic anemia. Eight hundred twenty-three patients (66.1%) experienced COVID-19 infection. Of these, 156 patients required hospitalization (19.0%), 47 required ICU care (5.7%), and 28 died (3.4%). Rates of hospitalization (9.3% versus 24.4%, p < 0.001), ICU admission (2.8% versus 7.6%, p = 0.013), and death (2.3% versus 4.3%, p = 0.202) in patients who had COVID-19 were lower in patients who received vaccination prior to infection. In adjusted logistic regression analysis, not having at least one COVID-19 vaccine significantly increased the odds of hospitalization and ICU admission.

CONCLUSION

Vaccination for COVID-19 in the IEI population appears safe and attenuates COVID-19 severity.

Human STAT1 gain of function with chronic mucocutaneous candidiasis: A comprehensive review for strengthening the connection between bedside observations and laboratory research

Germline human heterozygous STAT1 gain-of-function (GOF) variants were first discovered a common cause of chronic mucocutaneous candidiasis (CMC) in 2011. Since then, numerous STAT1 GOF variants have been identified. A variety of clinical phenotypes, including fungal, viral, and bacterial infections, endocrine disorders, autoimmunity, malignancy, and aneurysms, have recently been revealed for STAT1 GOF variants, which has led to the expansion of the clinical spectrum associated with STAT1 GOF. Among this broad range of complications, it has been determined that invasive infections, aneurysms, and malignancies are poor prognostic factors for STAT1 GOF. The effectiveness of JAK inhibitors as a therapeutic option has been established, although further investigation of their long-term utility and side effects is needed. In contrast to the advancements in treatment options, the precise molecular mechanism underlying STAT1 GOF remains undetermined. Two primary hypotheses for this mechanism involve impaired STAT1 dephosphorylation and increased STAT1 protein levels, both of which are still controversial. A precise understanding of the molecular mechanism is essential for not only advancing diagnostics but also developing therapeutic interventions. Here, we provide a comprehensive review of STAT1 GOF with the aim of establishing a stronger connection between bedside observations and laboratory research.

Unmasking the potential of secretory IgA and its pivotal role in protection from respiratory viruses

Mucosal immunity has regained its spotlight amidst the ongoing Coronavirus disease 19 (COVID-19) pandemic, with numerous studies highlighting the crucial role of mucosal secretory IgA (SIgA) in protection against Severe acute respiratory syndrome coronavirus-2 or SARS-CoV-2 infections. The observed limitations in the efficacy of currently authorized COVID-19 vaccines in inducing effective mucosal immune responses remind us of the limitations of systemic vaccination in promoting protective mucosal immunity. This resurgence of interest has motivated the development of vaccine platforms capable of enhancing mucosal responses, specifically the SIgA response, and the development of IgA-based therapeutics. Recognizing viral respiratory infections as a global threat, we would like to comprehensively review the existing knowledge on mucosal immunity, with a particular emphasis on SIgA, in the context of SARS-CoV-2, influenza, and Respiratory Syncytial Virus (RSV) infections. This review aims to describe the structural and functional specificities of SIgA, along with its nuanced role in combating influenza, RSV, and SARS-CoV-2 infections. Subsequent sections further elaborate promising vaccine strategies, including mucosal vaccines against Influenza, RSV, and SARS-CoV-2 respiratory viruses, currently undergoing preclinical and clinical development. Additionally, we address the challenges associated with mucosal vaccine development, concluding with a discussion on IgA-based therapeutics as a promising platform for the treatment of viral respiratory infections. This comprehensive review not only synthesizes current insights into mucosal immunity but also identifies critical knowledge gaps, strengthening the way for further advancements in our current understanding and approaches to combat respiratory viral threats.

New primary immunodeficiencies 2023 update

PURPOSE OF REVIEW

Primary immunodeficiency diseases (PIDs), also called inborn errors of immunity (IEI), are genetic disorders characterized by increased susceptibility to infection and/or aberrant regulation of immunological pathways. This review summarizes and highlights the new IEI disorders in the International Union of Immunological Societies (IUIS) 2022 report and current trends among new PIDs.

RECENT FINDINGS

Since the 2019 IUIS report and the 2021 IUIS interim update, the IUIS IEI classification now includes 485 validated IEIs. Increasing utilization of genetic testing and advances in the strategic evaluation of genetic variants has continued to drive the identification of, not only novel IEI disorders, but additional genetic etiologies for known IEI disorders and phenotypes.

SUMMARY

The recognition of new IEIs continues to advance at a rapid pace, which is due in part to increased performance and application of genetic modalities as well as expansion of the underlying science that is applied to convincingly establish causality. These disorders, as a whole, continue to emphasize the specificity of immunity, complexity of immune mechanisms, and the fine balance that defines immune homeostasis.

Evaluation of Genetic or Cellular Impairments in Type I IFN Immunity in a Cohort of Young Adults with Critical COVID-19

Several genetic and immunological risk factors for severe COVID-19 have been identified, with monogenic conditions relating to 13 genes of type I interferon (IFN) immunity proposed to explain 4.8% of critical cases. However, previous cohorts have been clinically heterogeneous and were not subjected to thorough genetic and immunological analyses. We therefore aimed to systematically investigate the prevalence of rare genetic variants causing inborn errors of immunity (IEI) and functionally interrogate the type I IFN pathway in young adults that suffered from critical COVID-19 yet lacked comorbidities. We selected and clinically characterized a cohort of 38 previously healthy individuals under 50 years of age who were treated in intensive care units due to critical COVID-19. Blood samples were collected after convalescence. Two patients had IFN-α autoantibodies. Genome sequencing revealed very rare variants in the type I IFN pathway in 31.6% of the patients, which was similar to controls. Analyses of cryopreserved leukocytes did not indicate any defect in plasmacytoid dendritic cell sensing of TLR7 and TLR9 agonists in patients carrying variants in these pathways. However, lymphocyte STAT phosphorylation and protein upregulation upon IFN-α stimulation revealed three possible cases of impaired type I IFN signaling in carriers of rare variants. Together, our results suggest a strategy of functional screening followed by genome analyses and biochemical validation to uncover undiagnosed causes of critical COVID-19.

Detection of SARS-CoV-2-Specific Cells Utilizing Whole Proteins and/or Peptides in Human PBMCs Using IFN-ƴ ELISPOT Assay

SARS-CoV-2 continues to threaten global public health, making COVID-19 immunity studies of utmost importance. Waning of antibody responses postinfection and/or vaccination and the emergence of immune escape variants have been ongoing challenges in mitigating SARS-CoV-2 morbidity and mortality. While a tremendous amount of work has been done to characterize humoral immune responses to SARS-CoV-2 virus and vaccines, cellular immunity, mediated by T cells, is critical for efficient viral control and protection and demonstrates high durability and cross-reactivity to coronavirus variants. Thus, ELISPOT, a standard assay for antigen-specific cellular immune response assessment, allows us to evaluate SARS-CoV-2-specific T-cell response by quantifying the frequency of SARS-CoV-2-specific cytokine-secreting cells in vitro. We have outlined a detailed procedure to study T-cell recall responses to SARS-CoV-2 in human peripheral blood mononuclear cells (PBMCs) following infection and/or vaccination using an optimized IFN-γ ELISPOT assay. Our methodologies can be adapted to assess other cytokines and are a useful tool for studying other viral pathogen and/or peptide-specific T-cell responses.

SARS-CoV-2 convalescence and hybrid immunity elicits mucosal immune responses

BACKGROUND

Mucosal antibodies play a key role in the protection against SARS-CoV-2 infection in the upper respiratory tract, and potentially in limiting virus replication and therefore onward transmission. While systemic immunity to SARS-CoV-2 is well understood, we have a limited understanding about the antibodies present on the nasal mucosal surfaces.

METHODS

In this study, we evaluated SARS-CoV-2 mucosal antibodies following previous infection, vaccination, or a combination of both. Paired nasal fluid and serum samples were collected from 143 individuals, which include convalescent, vaccinated, or breakthrough infections.

FINDINGS

We detected a high correlation between IgG responses in serum and nasal fluids, which were higher in both compartments in vaccinated compared to convalescent participants. Contrary, nasal and systemic SARS-CoV-2 IgA responses were weakly correlated, indicating a compartmentalization between the local and systemic IgA responses. SARS-CoV-2 secretory component IgA (s-IgA) antibodies, present exclusively on mucosal surfaces, were detected in the nasal fluid only in a minority of vaccinated subjects and were significantly higher in previously infected individuals. Depletion of IgA antibodies in nasal fluids resulted in a tremendous reduction of neutralization activity against SARS-CoV-2, indicating that IgA is the crucial contributor to neutralization in the nasal mucosa. Neutralization against SARS-CoV-2 was higher in the mucosa of subjects with previous SARS-CoV-2 infections compared to vaccinated participants.

INTERPRETATION

In summary, we demonstrate that currently available vaccines elicit strong systemic antibody responses, but SARS-CoV-2 infection generates higher titers of binding and neutralizing mucosal antibodies. Our results support the importance to develop SARS-CoV-2 vaccines that elicit mucosal antibodies.

FUNDING

The work was funded by the COVID-19 National Research Program 78 (grant number 198412) of the Swiss National Science Foundation.

Clinical Course, Therapeutic Management and Outcome of Coronavirus Disease in Patients With Inborn Errors of Immunity: A Retrospective Multicenter Experience From Iran

BACKGROUND

Inborn errors of immunity (IEIs) are characterized by defects in the structure and function of the immune system. This study was designed to assess the impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection on this potentially particularly susceptible group of patients.

METHODS

This retrospective cross-sectional study analyzed patients from 3 referral immunodeficiency centers in Iran. The demographic, clinical, laboratory and therapeutical data of confirmed IEI patients with SARS-CoV-2 infection were collected and analyzed.

RESULTS

A total of 19 IEI patients, 52.6% male and 47.4% female, with coronavirus disease 2019 (COVID-19) were enrolled. The most common diagnosed IEIs were (severe) combined immunodeficiency ((S)CID) (9, 47.4%) and predominantly antibody deficiencies (7, 36.8%). The main presenting symptoms included fever (16, 84.2%), cough (12, 63.2%), dyspnea (9, 47.4%) and myalgia (8, 42.1%). Among additional preexisting comorbidities, atopy ( P = 0.087) and renal disorders ( P = 0.087) were more strongly associated with the development of respiratory failure, although not statistically significant. SARS-CoV-2 infection was determined by polymerase chain reaction (n = 19, 100%) within a median (interquartile range) of 1 (0-6) days following admission. Among all laboratory indices, thrombocytopenia ( P = 0.009) was associated with a need for intensive care unit admission. The overall mortality rate was 36.9% and highest among (S)CID patients (4, 44.4%).

CONCLUSIONS

Severe COVID-19 most frequently affected (S)CID and predominantly antibody deficiencies patients among this multicenter Iranian cohort. Further studies are required to evaluate the impact of additional preexisting comorbidities and the development of thrombocytopenia on the severity and prognosis of COVID-19 in IEIs.

Immunosenescence and Inflammaging in COVID-19

Despite knowledge gaps in understanding the full spectrum of the hyperinflammatory phase caused by SARS-CoV-2, according to the World Health Organization (WHO), COVID-19 is still the leading cause of death worldwide. Susceptible people to severe COVID-19 are those with underlying medical conditions or those with dysregulated and senescence-associated immune responses. As the immune system undergoes aging in the elderly, such drastic changes predispose them to various diseases and affect their responsiveness to infections, as seen in COVID-19. At-risk groups experience poor prognosis in terms of disease recovery. Changes in the quantity and quality of immune cell function have been described in numerous literature sites. Impaired immune cell function along with age-related metabolic changes can lead to features such as hyperinflammatory response, immunosenescence, and inflammaging in COVID-19. Inflammaging is related to the increased activity of the most inflammatory factors and is the main cause of age-related diseases and tissue failure in the elderly. Since hyperinflammation is a common feature of most severe cases of COVID-19, this pathway, which is not fully understood, leads to immunosenescence and inflammaging in some individuals, especially in the elderly and those with comorbidities. In this review, we shed some light on the age-related abnormalities of innate and adaptive immune cells and how hyperinflammatory immune responses contribute to the inflammaging process, leading to clinical deterioration. Further, we provide insights into immunomodulation-based therapeutic approaches, which are potentially important considerations in vaccine design for elderly populations.

Rethinking Immunological Risk: A Retrospective Cohort Study of Severe SARS-Cov-2 Infections in Individuals With Congenital Immunodeficiencies

BACKGROUND

Debates on the allocation of medical resources during the coronavirus disease 2019 (COVID-19) pandemic revealed the need for a better understanding of immunological risk. Studies highlighted variable clinical outcomes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections in individuals with defects in both adaptive and innate immunity, suggesting additional contributions from other factors. Notably, none of these studies controlled for variables linked with social determinants of health.

OBJECTIVE

To determine the contributions of determinants of health to risk of hospitalization for SARS-CoV-2 infection among individuals with inborn errors of immunodeficiencies.

METHODS

This is a retrospective, single-center cohort study of 166 individuals with inborn errors of immunity, aged 2 months through 69 years, who developed SARS-CoV-2 infections from March 1, 2020, through March 31, 2022. Risks of hospitalization were assessed using a multivariable logistic regression analysis.

RESULTS

The risk of SARS-CoV-2-related hospitalization was associated with underrepresented racial and ethnic populations (odds ratio [OR] 4.50; 95% confidence interval [95% CI] 1.57-13.4), a diagnosis of any genetically defined immunodeficiency (OR 3.32; 95% CI 1.24-9.43), obesity (OR 4.24; 95% CI 1.38-13.3), and neurological disease (OR 4.47; 95% CI 1.44-14.3). The COVID-19 vaccination was associated with reduced hospitalization risk (OR 0.52; 95% CI 0.31-0.81). Defects in T cell and innate immune function, immune-mediated organ dysfunction, and social vulnerability were not associated with increased risk of hospitalization after controlling for covariates.

CONCLUSIONS

The associations between race, ethnicity, and obesity with increased risk of hospitalization for SARS-CoV-2 infection indicate the importance of variables linked with social determinants of health as immunological risk factors for individuals with inborn errors of immunity.

SARS-CoV-2 pre-exposure prophylaxis with tixagevimab/cilgavimab (AZD7442) provides protection in inborn errors of immunity with antibody defects: a real-world experience

Background

Preventive strategies against severe COVID-19 in Inborn Errors of Immunity (IEI) include bivalent vaccines, treatment with SARS-CoV-2 monoclonal antibodies (mAbs), early antiviral therapies, and pre-exposure prophylaxis (PrEP).

Objective

To assess the effectiveness of the PrEP with tixagevimab/cilgavimab (AZD7442) in IEI with primary antibody defects during the COVID-19 Omicron wave.

Methods

A six-month prospective study evaluated the SARS-CoV-2 infection rate and the COVID-19 severity in the AZD7442 group, in the no-AZD7442 group, and in a group of patients with a recent SARS-CoV-2 infection (< three months). Spike-specific IgG levels were measured at regular intervals.

Results

Six out of thirty-three patients (18%) and 54/170 patients (32%) became infected in the AZD7442 group and in the no-AZD7442 group, respectively. Within 90 days post-administration, the AZD7442 group was 85% less likely to be infected and 82% less likely to have a symptomatic disease than the no-AZD7442 group. This effect was lost thereafter. In the entire cohort, no mortality/hospitalisation was observed. The control group of 35 recently infected patients was 88% and 92% less likely to be infected than the AZD7442 and no-AZD7442 groups. Serum anti-Spike IgG reached the highest peak seven days post-AZD7442 PrEP then decreased, remaining over 1000 BAU/mL 180 days thereafter.

Conclusion

In patients with IEI and antibody defects, AZD7442 prophylaxis had a transient protective effect, possibly lost possibly because of the appearance of new variants. However, PrEP with newer mAbs might still represent a feasible preventive strategy in the future in this population.

Potential network markers and signaling pathways for B cells of COVID-19 based on single-cell condition-specific networks

To explore the potential network markers and related signaling pathways of human B cells infected by COVID-19, we performed standardized integration and analysis of single-cell sequencing data to construct conditional cell-specific networks (CCSN) for each cell. Then the peripheral blood cells were clustered and annotated based on the conditional network degree matrix (CNDM) and gene expression matrix (GEM), respectively, and B cells were selected for further analysis. Besides, based on the CNDM of B cells, the hub genes and 'dark' genes (a gene has a significant difference between case and control samples not in a gene expression level but in a conditional network degree level) closely related to COVID-19 were revealed. Interestingly, some of the 'dark' genes and differential degree genes (DDGs) encoded key proteins in the JAK-STAT pathway, which had antiviral effects. The protein p21 encoded by the 'dark' gene CDKN1A was a key regulator for the COVID-19 infection-related signaling pathway. Elevated levels of proteins encoded by some DDGs were directly related to disease severity of patients with COVID-19. In short, the proteins encoded by 'dark' genes complement some missing links in COVID-19 and these signaling pathways played an important role in the growth and activation of B cells.

Characterization of the antispike IgG immune response to COVID-19 vaccines in people with a wide variety of immunodeficiencies

Research on coronavirus disease 2019 vaccination in immune-deficient/disordered people (IDP) has focused on cancer and organ transplantation populations. In a prospective cohort of 195 IDP and 35 healthy volunteers (HV), antispike immunoglobulin G (IgG) was detected in 88% of IDP after dose 2, increasing to 93% by 6 months after dose 3. Despite high seroconversion, median IgG levels for IDP never surpassed one-third that of HV. IgG binding to Omicron BA.1 was lowest among variants. Angiotensin-converting enzyme 2 pseudo-neutralization only modestly correlated with antispike IgG concentration. IgG levels were not significantly altered by receipt of different messenger RNA-based vaccines, immunomodulating treatments, and prior severe acute respiratory syndrome coronavirus 2 infections. While our data show that three doses of coronavirus disease 2019 vaccinations induce antispike IgG in most IDP, additional doses are needed to increase protection. Because of the notably reduced IgG response to Omicron BA.1, the efficacy of additional vaccinations, including bivalent vaccines, should be studied in this population.

Management and outcome of COVID-19 in CTLA-4 insufficiency

Despite the high incidence of COVID-19 worldwide, clinical experience with severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) in inborn errors of immunity remains limited. Recent studies have shown that patients with defects in type 1 interferon (IFN)-related pathways or those with autoantibodies against type 1 IFNs develop severe COVID-19. We reported the clinical course of 22 patients with CTLA-4 insufficiency and COVID-19 and retrospectively examined autoantibodies against type 1 IFNs at baseline. Data were obtained from the patient interviews and chart reviews. Screening for anti-IFN autoantibodies was performed using a multiplex particle-based assay. Student t test, Mann Whitney, analysis of variance, or χ2 tests were used where appropriate. Twenty-two patients aged from 8 months to 54 years, with genetically confirmed CLTA-4 insufficiency, developed COVID-19 from 2020 to 2022. The most common symptoms were fever, cough, and nasal congestion, and the median duration of illness was 7.5 days. Twenty patients (91%) developed mild COVID-19 and were treated as outpatients. Two patients were hospitalized because of COVID-19 pneumonia but did not require mechanical ventilation. Ten (45%) patients were vaccinated at the time of their first COVID-19 infection. Eleven patients received outpatient treatment with monoclonal antibodies against the SARS-CoV-2 spike protein. During the study period, 17 patients were vaccinated against SARS-CoV-2, with no severe vaccine-related adverse effects. Although median anti-S titers following vaccination or infection were lower in patients receiving immunoglobulin replacement therapy (IGRT) (349 IU/dL) than in those not receiving IGRT (2594 IU/dL; P = .15); 3 of 9 patients on IGRT developed titers >2000 IU/dL. All patients tested negative for autoantibodies against IFN-α, IFN-β, and IFN-ω at baseline. Most patients with CTLA-4 insufficiency and COVID-19 had nonsevere disease, lacked autoantibodies against type 1 IFNs, and tolerated messenger RNA vaccines with few adverse effects. Whether our findings can be extrapolated to patients receiving CTLA-4-targeting checkpoint inhibitors requires further studies.

Impact of COVID-19 Pandemic on Clinical Care of Patients and Psychosocial Health of Affected Families with Chronic Granulomatous Disease: an Observational Study from North India

Day-to-day clinical management of patients with inborn errors of immunity, including chronic granulomatous disease (CGD), has been affected by the coronavirus disease-2019 (COVID-19) pandemic. There is a dearth of information on impact of this pandemic on clinical care of children with CGD and psychological profile of the caretakers. Among the 101 patients with CGD followed up in our center, 5 children developed infection/complications associated with COVID-19. Four of these children had a mild clinical course, while 1 child developed features of multisystem inflammatory syndrome in children (MISC) requiring intravenous glucocorticoids. Parents and caretakers of CGD patients (n = 21) and 21 healthy adults with similar ages and genders were also evaluated on the following scales and questionnaires: COVID-19 Fear Scale (FCV 19S), Impact of Event Scale (IES-R), Depression, Anxiety, and Stress Scale (DASS 21), Preventive COVID-19 Behavior Scale (PCV 19BS), and a "COVID-19 Psychological wellbeing questionnaire." Median age of the parents/caregivers was 41.76 years (range: 28-60 years). Male:female ratio was 2:1. In the study group, 71.4% had higher IES scores compared to 14.3% in controls. The caregivers had a high prevalence of stress, anxiety, avoidance behavior, and depression compared to controls (p < 0.001). Children with CGD have had predominantly mild infection with COVID-19; however, caregivers/parents of these children were at risk of developing psychological distress. The COVID-19 pandemic has brought to light the importance of patients' and caretakers' mental health which needs periodic assessment and appropriate interventions.

Immunoglobulin Replacement Therapy During COVID-19 Pandemic: Practical and Psychological Impact in Patients with Antibody Deficiency

PURPOSE

The COVID-19 pandemic has impacted on how health services deliver care and the mental health of the population. Due to their clinical vulnerability, to reduce in-hospital attendances during the COVID-19 pandemic, modifications in immunoglobulin treatment regimens were made for patients with antibody deficiency. These patients were also likely to experience social isolation due to shielding measure that were advised. We aimed to investigate the impact of modifying immunoglobulin treatment regimen on infection and mental health burden during shielding restrictions.

METHOD

Patients on immunoglobulin replacement therapy (IGRT) responded to a standardised questionnaire examining self-reported infection frequency, anxiety (GAD-7), depression (PHQ-8), fatigue (FACIT), and quality of life during the pandemic. Infection frequency and immunoglobulin trough levels were compared to pre-pandemic levels.

RESULTS

Patients who did not change treatment modality or those who received immunoglobulin replacement at home during the pandemic reported fewer infections. In patients who received less frequent hospital infusions, there was no significant increase in infections whilst immunoglobulin trough levels remained stable. There was no significant difference in anxiety, or depression scores between the treatment modality groups. Patients reported higher fatigue scores compared to the pre-COVID general population and in those discharged following hospitalisation for COVID.

CONCLUSION

Changing immunoglobulin treatment regimen did not negatively impact infection rates or psychological wellbeing. However, psychological welfare should be prioritised for this group particularly given uncertainties around COVID-19 vaccination responsiveness and continued social isolation for many.

Rare Variants in Primary Immunodeficiency Genes and Their Functional Partners in Severe COVID-19

The development of severe COVID-19, which is a complex multisystem disease, is thought to be associated with many genes whose action is modulated by numerous environmental and genetic factors. In this study, we focused on the ideas of the omnigenic model of heritability of complex traits, which assumes that a small number of core genes and a large pool of peripheral genes expressed in disease-relevant tissues contribute to the genetics of complex traits through interconnected networks. We hypothesized that primary immunodeficiency disease (PID) genes may be considered as core genes in severe COVID-19, and their functional partners (FPs) from protein-protein interaction networks may be considered as peripheral near-core genes. We used whole-exome sequencing data from patients aged ≤ 45 years with severe (n = 9) and non-severe COVID-19 (n = 11), and assessed the cumulative contribution of rare high-impact variants to disease severity. In patients with severe COVID-19, an excess of rare high-impact variants was observed at the whole-exome level, but maximal association signals were detected for PID + FP gene subsets among the genes intolerant to LoF variants, haploinsufficient and essential. Our exploratory study may serve as a model for new directions in the research of host genetics in severe COVID-19.

Clinical and immunological outcomes of SARS-CoV-2 infection in patients with inborn errors of immunity receiving different brands and doses of COVID-19 vaccines

Introduction

Vaccines against severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) provide successful control of the coronavirus-2019 (COVID-19) pandemic. The safety and immunogenicity studies are encouraging in patients with inborn errors of immunity (IEI); however, data about mortality outcomes and severe disease after vaccination still need to be fully addressed. Therefore, we aimed to determine the clinical and immunological outcomes of SARS-CoV-2 infection in patients with IEI who have received vaccination.

Materials and Methods

Eighty-eight patients with a broad range of molecular etiologies were studied; 45 experienced SARS-CoV-2 infection. Infection outcomes were analyzed in terms of genetic etiology, background clinical characteristics, and immunization history, including the type and number of doses received and the time elapsed since vaccination. In addition, anti-SARS-CoV-2 antibodies were quantified using electrochemiluminescent immunoassay.

Results

Patients were immunized using one of the three regimens: inactivated (Sinovac, Coronavac®), mRNA (BNT162b2, Comirnaty®, Pfizer-Biontech), and a combination. All three regimens induced comparable anti-SARS-CoV-2 IgG levels, with no differences in the adverse events. Among 45 patients with COVID-19, 26 received a full course of vaccination, while 19 were vaccine-naive or received incomplete dosing. No patients died due to COVID-19 infection. The fully immunized group had a lower hospitalization rate (23% vs. 31.5%) and a shorter symptomatic phase than the others. Among the fully vaccinated patients, serum IgM and E levels were significantly lower in hospitalized patients than non-hospitalized patients.

Conclusion

COVID-19 vaccines were well-tolerated by the IEI patients, and a full course of immunization was associated with lower hospitalization rates and a shorter duration of COVID-19 symptoms.

The impact of immunocompromise on outcomes of COVID-19 in children and young people-a systematic review and meta-analysis

Background

Despite children and young people (CYP) having a low risk for severe coronavirus disease 2019 (COVID-19) outcomes, there is still a degree of uncertainty related to their risk in the context of immunodeficiency or immunosuppression, primarily due to significant reporting bias in most studies, as CYP characteristically experience milder or asymptomatic COVID-19 infection and the severe outcomes tend to be overestimated.

Methods

A comprehensive systematic review to identify globally relevant studies in immunosuppressed CYP and CYP in general population (defined as younger than 25 years of age) up to 31 October 2021 (to exclude vaccinated populations) was performed. Studies were included if they reported the two primary outcomes of our study, admission to intensive therapy unit (ITU) and mortality, while data on other outcomes, such as hospitalization and need for mechanical ventilation were also collected. A meta-analysis estimated the pooled proportion for each severe COVID-19 outcome, using the inverse variance method. Random effects models were used to account for interstudy heterogeneity.

Findings

The systematic review identified 30 eligible studies for each of the two populations investigated: immunosuppressed CYP (n = 793) and CYP in general population (n = 102,022). Our meta-analysis found higher estimated prevalence for hospitalization (46% vs. 16%), ITU admission (12% vs. 2%), mechanical ventilation (8% vs. 1%), and increased mortality due to severe COVID-19 infection (6.5% vs. 0.2%) in immunocompromised CYP compared with CYP in general population. This shows an overall trend for more severe outcomes of COVID-19 infection in immunocompromised CYP, similar to adult studies.

Interpretation

This is the only up-to-date meta-analysis in immunocompromised CYP with high global relevance, which excluded reports from hospitalized cohorts alone and included 35% studies from low- and middle-income countries. Future research is required to characterize individual subgroups of immunocompromised patients, as well as impact of vaccination on severe COVID-19 outcomes.

Systematic Review Registration

PROSPERO identifier, CRD42021278598.

COVID-19 Vaccination In Patients with Inborn Errors of Immunity Reduces Hospitalization and Critical Care Needs Related to COVID-19: A USIDNET Report

Background

The CDC and ACIP recommend COVID-19 vaccination for patients with inborn errors of immunity (IEI). Not much is known about vaccine safety in IEI and whether vaccination attenuates infection severity in IEI.

Objective

To estimate COVID-19 vaccination safety and examine effect on outcomes in patients with IEI.

Methods

We built a secure registry database in conjunction with the United States Immunodeficiency Network to examine vaccination frequency and indicators of safety and effectiveness in IEI patients. The registry opened on January 1, 2022 and closed on August 19, 2022.

Results

Physicians entered data on 1,245 patients from 24 countries. The most common diagnoses were antibody deficiencies (63.7%). At least 1 COVID-19 vaccine was administered to 806 patients (64.7%), and 216 patients received vaccination prior to the development of COVID-19. The most common vaccines administered were mRNA-based (84.0%). Seventeen patients were reported to seek outpatient clinic or emergency room care for a vaccine-related complication and one patient was hospitalized for symptomatic anemia. Eight hundred twenty-three patients (66.1%) experienced COVID-19 infection. Of these, 156 patients required hospitalization (19.0%), 47 required ICU care (5.7%), and 28 died (3.4%). Rates of hospitalization (9.3% versus 24.4%, p<0.001), ICU admission (2.8% versus 7.6%, p=0.013), and death (2.3% versus 4.3%, p=0.202) in patients who had COVID-19 were lower in patients who received vaccination prior to infection. In adjusted logistic regression analysis, not having at least one COVID-19 vaccine significantly increased the odds of hospitalization and ICU admission.

Conclusion

Vaccination for COVID-19 in the IEI population appears safe and attenuates COVID-19 severity.

Alterations in B and NK cells highly correlate with disease severity in children with COVID-19

Background/aim

Children with coronavirus disease 2019 (COVID-19) present milder symptoms than adults and are at lower risk of hospitalization and life-threatening complications. However, the kinetics of lymphocyte subsets and serum immunoglobulins in the peripheral blood during COVID-19 infection remains unclear. In this study, it was aimed to determine the changes in hematological and immunological parameters, especially in the lymphocyte subsets, in the peripheral blood of children with different COVID-19 disease severity.

Materials and methods

The study was planned as a prospective cohort and included 68 children aged 0-18 years who were admitted to Ege University Faculty of Medicine Department of Pediatrics and diagnosed with COVID-19 infection between May 2020 and December 2021. In addition to demographic characteristics, clinical findings, and severity criteria, hematological, biochemical, and immunological laboratory (T/B lymphocyte subgroups, serum immunoglobulins) results were noted and examined if there were some correlations between disease severity and the laboratory values.

Results

In the study group, while 60.6% (n = 40) of the patients received treatment in the hospital, 10.6% (n = 7) needed intensive care treatment. Lymphopenia (35.3%) was more common than neutropenia (14.7%) in the COVID-19-infected children. CD19+ B cells were low in a very high percentage of patients (26.5%), and 16.2% had low levels of NK cells. Significant correlation between disease severity and CD19+lymphocytes, CD19+CD38+IgMlow lymphocytes, CD19+CD38+CD27highIgMhigh lymphocytes, CD19+CD81+ lymphocytes (p = 0.001, p = 0.008, p = 0.014, p = 0.025, and rs = 0.394, rs = 0.326, rs = 0.303, rs = 0.280, respectively), significant inverse correlation between disease severity and absolute lymphocytes counts and CD3-CD16+CD56+ lymphocytes (p = 0.004, 0.014, and rs = -0.353, rs = -0.304, respectively) were observed. The percentage of hospitalized patients with low CD3 levels (15%) was significantly higher than that of the outpatients with low CD3 levels.

Conclusion

As the severity of the disease increased, the CD19+, CD19+CD38+IgMlow, CD19+CD38+CD27highIgMhigh, and CD19+CD81+ lymphocytes percentages increased, while the lymphocyte count and NK cell percentage decreased. Therefore, detecting these prognostic immunobiomarkers related to the severity of the disease may contribute considerably to management of the illness.

Severity of SARS-CoV-2 infection in children with inborn errors of immunity (primary immunodeficiencies): a systematic review

BACKGROUND

Inborn errors of immunity (IEIs) are considered significant challenges for children with IEIs, their families, and their medical providers. Infections are the most common complication of IEIs and children can acquire coronavirus disease 2019 (COVID-19) even when protective measures are taken.

OBJECTIVES

To estimate the incidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in children with IEIs and analyse the demographic parameters, clinical characteristics and treatment outcomes in children with IEIs with COVID-19 illness.

METHODS

For this systematic review, we searched ProQuest, Medline, Embase, PubMed, CINAHL, Wiley online library, Scopus and Nature through the Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA) guideline for studies on the development of COVID-19 in children with IEIs, published from December 1, 2019 to February 28, 2023, with English language restriction.

RESULTS

Of the 1095 papers that were identified, 116 articles were included in the systematic review (73 case report, 38 cohort 4 case-series and 1 case-control studies). Studies involving 710 children with IEIs with confirmed COVID-19 were analyzed. Among all 710 IEIs pediatric cases who acquired SARS-CoV-2, some children were documented to be admitted to the intensive care unit (ICU) (n = 119, 16.8%), intubated and placed on mechanical ventilation (n = 87, 12.2%), suffered acute respiratory distress syndrome (n = 98, 13.8%) or died (n = 60, 8.4%). Overall, COVID-19 in children with different IEIs patents resulted in no or low severity of disease in more than 76% of all included cases (COVID-19 severity: asymptomatic = 105, mild = 351, or moderate = 88). The majority of children with IEIs received treatment for COVID-19 (n = 579, 81.5%). Multisystem inflammatory syndrome in children (MIS-C) due to COVID-19 in children with IEIs occurred in 103 (14.5%). Fatality in children with IEIs with COVID-19 was reported in any of the included IEIs categories for cellular and humoral immunodeficiencies (n = 19, 18.6%), immune dysregulatory diseases (n = 17, 17.9%), innate immunodeficiencies (n = 5, 10%), bone marrow failure (n = 1, 14.3%), complement deficiencies (n = 1, 9.1%), combined immunodeficiencies with associated or syndromic features (n = 7, 5.5%), phagocytic diseases (n = 3, 5.5%), autoinflammatory diseases (n = 2, 3%) and predominantly antibody deficiencies (n = 5, 2.5%). Mortality was COVID-19-related in a considerable number of children with IEIs (29/60, 48.3%). The highest ICU admission and fatality rates were observed in cases belonging to cellular and humoral immunodeficiencies (26.5% and 18.6%) and immune dysregulatory diseases (35.8% and 17.9%) groups, especially in children infected with SARS-CoV-2 who suffered severe combined immunodeficiency (28.6% and 23.8%), combined immunodeficiency (25% and 15%), familial hemophagocytic lymphohistiocytosis (40% and 20%), X-linked lymphoproliferative diseases-1 (75% and 75%) and X-linked lymphoproliferative diseases-2 (50% and 50%) compared to the other IEIs cases.

CONCLUSION

Children with IEIs infected with SARS-CoV-2 may experience higher rates of ICU admission and mortality in comparison with the immunocompetent pediatric populations. Underlying immune defects does seem to be independent risk factors for severe SARS-CoV-2 infection in children with IEIs, a number of children with SCID and CID were reported to have prolonged infections-though the number of patients is small-but especially immune dysregulation diseases (XLP1 and XLP2) and innate immunodeficiencies impairing type I interferon signalling (IFNAR1, IFNAR2 and TBK1).

SARS-CoV-2 Infection and Response to COVID-19 Vaccination in Patients With Primary Immunodeficiencies

Primary immunodeficiencies (PIDs) are heterogeneous, rare disorders that increase susceptibility to infection and/or immune dysregulation. Individuals with certain PIDs are at high risk of severe or fatal outcomes from SARS-CoV-2 infections (the causative agent of COVID-19), either due to the underlying PID and/or due to the presence of comorbidities such as severe lung and liver disease. Vaccination remains the primary strategy to protect individuals with PID from COVID-19. However, populations with PID exhibit variable vaccine seroresponse rates, antibody titers, and neutralization activity depending on the type of PID and/or COVID-19 vaccine, and consequently, are at an elevated risk of severe disease. In this article, we review the COVID-19 burden in patients with PIDs and focus in-depth on findings from patients with predominantly antibody deficiencies or combined immunodeficiencies. We conclude by providing COVID-19 vaccination recommendations for this population.

Detection of SARS-CoV-2 Antibodies in Immunoglobulin Products

BACKGROUND

For patients with primary antibody deficiency, the first line of therapy is replacement with immunoglobulin (Ig) products. Prior to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, Ig products did not contain antibodies with specificity for this virus, and there have been limited data on the antibodies present in the Ig products in current use.

OBJECTIVE

To quantitatively examine SARS-CoV-2 antibodies in current Ig products.

METHODS

We examined 142 unique lots of 11 different Ig products intended for intravenous and/or subcutaneous delivery for IgG-binding activities against recombinant SARS-CoV-2 receptor binding domain, spike, and nucleocapsid proteins by enzyme-linked immunosorbent assays. In addition, to assess functionality, 48 of these unique lots were assessed for their ability to inhibit the variants SARS-CoV-2 Ancestral, Alpha, Beta, Delta, and Omicron spike binding to angiotensin-converting enzyme 2 (ACE2).

RESULTS

Significantly increased antibody values were observed for products manufactured after the year 2020 (expiration dates 2023-2024), as compared with Ig products before 2020 (prepandemic). Sixty percent and 85% of the Ig products with expiration dates of 2023 and 2024 were positive for antibody to SARS-CoV-2 proteins, respectively. The area under the curve values were significantly higher in products with later expiration dates. Later dates of expiration were also strongly correlated with inhibition of ACE2-binding activity; however, a decline in inhibition activity was observed with later variants.

CONCLUSIONS

Overall, more recent Ig products (expiration dates 2023-2025) contained significantly higher binding and inhibition activities against SARS-CoV-2 proteins, compared with earlier, or prepandemic products. Normal donor SARS-CoV-2 antibodies are capable of inhibiting ACE2-binding activities and may provide a therapeutic benefit for patients who do not make a robust vaccine response.

Human genetic and immunological determinants of SARS-CoV-2 and Epstein-Barr virus diseases in childhood: Insightful contrasts

There is growing evidence to suggest that severe disease in children infected with common viruses that are typically benign in other children can result from inborn errors of immunity or their phenocopies. Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a cytolytic respiratory RNA virus, can lead to acute hypoxemic COVID-19 pneumonia in children with inborn errors of type I interferon (IFN) immunity or autoantibodies against IFNs. These patients do not appear to be prone to severe disease during infection with Epstein-Barr virus (EBV), a leukocyte-tropic DNA virus that can establish latency. By contrast, various forms of severe EBV disease, ranging from acute hemophagocytosis to chronic or long-term illnesses, such as agammaglobulinemia and lymphoma, can manifest in children with inborn errors disrupting specific molecular bridges involved in the control of EBV-infected B cells by cytotoxic T cells. The patients with these disorders do not seem to be prone to severe COVID-19 pneumonia. These experiments of nature reveal surprising levels of redundancy of two different arms of immunity, with type I IFN being essential for host defense against SARS-CoV-2 in respiratory epithelial cells, and certain surface molecules on cytotoxic T cells essential for host defense against EBV in B lymphocytes.

Exploring Factors Influencing Changes in Incidence and Severity of Multisystem Inflammatory Syndrome in Children

Multisystem inflammatory syndrome (MIS-C) is a rare condition associated with COVID-19 affecting children, characterized by severe and aberrant systemic inflammation leading to nonspecific symptoms, such as gastrointestinal, cardiac, respiratory, hematological, and neurological disorders. In the last year, we have experienced a progressive reduction in the incidence and severity of MIS-C, reflecting the worldwide trend. Thus, starting from the overall trend in the disease in different continents, we reviewed the literature, hypothesizing the potential influencing factors contributing to the reduction in cases and the severity of MIS-C, particularly the vaccination campaign, the spread of different SARS-CoV-2 variants (VOCs), and the changes in human immunological response. The decrease in the severity of MIS-C and its incidence seem to be related to a combination of different factors rather than a single cause. Maturation of an immunological memory to SARS-CoV-2 over time, the implication of mutations of key amino acids of S protein in VOCs, and the overall immune response elicited by vaccination over the loss of neutralization of vaccines to VOCs seem to play an important role in this change.

Vaccination prevents severe COVID-19 outcome in patients with neutralizing type 1 interferon autoantibodies

A hallmark of patients with autoimmune polyendocrine syndrome type 1 (APS-1) is serological neutralizing autoantibodies against type 1 interferons (IFN-I). The presence of these antibodies has been associated with severe course of COVID-19. The aims of this study were to investigate SARS-CoV-2 vaccine tolerability and immune responses in a large cohort of patients with APS-1 (N = 33) and how these vaccinated patients coped with subsequent infections. We report that adult patients with APS-1 were able to mount adequate SARS-CoV-2 spike-specific antibody responses after vaccination and observed no signs of decreased tolerability. Compared with age- and gender-matched healthy controls, patients with APS-1 had considerably lower peak antibody responses resembling elderly persons, but antibody decline was more rapid in the elderly. We demonstrate that vaccination protected patients with APS-1 from severe illness when infected with SARS-CoV-2 virus, overriding the systemic danger of IFN-I autoantibodies observed in previous studies.

Struggling with COVID-19 in Adult Inborn Errors of Immunity Patients: A Case Series of Combination Therapy and Multiple Lines of Therapy for Selected Patients

BACKGROUND

The SARS-CoV-2 infection is now a part of the everyday lives of immunocompromised patients, but the choice of treatment and the time of viral clearance can often be complex, exposing patients to possible complications. The role of the available antiviral and monoclonal therapies is a matter of debate, as are their effectiveness and potential related adverse effects. To date, in the literature, the amount of data on the use of combination therapies and on the multiple lines of anti-SARS-CoV-2 therapy available to the general population and especially to inborn error of immunity (IEI) patients is small.

METHODS

Here, we report a case series of five adult IEI patients managed as inpatients at three Italian IEI referral centers (Rome, Treviso, and Cagliari) treated with combination therapy or multiple therapeutic lines for SARS-CoV-2 infection, such as monoclonal antibodies (mAbs), antivirals, convalescent plasma (CP), mAbs plus antiviral, and CP combined with antiviral.

RESULTS

This study may support the use of combination therapy against SARS-CoV-2 in complicated IEI patients with predominant antibody deficiency and impaired vaccine response.

Pediatric cancer care management during the COVID-19 pandemic: a review of the literature and a single-centre real-life experience of an Italian pediatric oncology unit

INTRODUCTION

The severe acute respiratory syndrome coronavirus-2 pandemic significantly affected clinical practice, also in pediatric oncology units. Cancer patients needed to be treated with an adequate dose density despite the SARS-CoV-2 infection, balancing risks of developing severe COVID-19 disease.

AREAS COVERED

Although the pandemic spread worldwide, the prevalence of affected children was low. The percentage of children with severe illness was approximately 1-6%. Pediatric cancer patients represent a prototype of a previously healthy immune system that is hampered by the tumor itself and treatments, such as chemotherapy and steroids. Through a review of the literature, we reported the immunological basis of the response to SARS-CoV-2 infection, the existing antiviral treatments used in pediatric cancer patients, and the importance of vaccination. In conclusion, we reported the real-life experience of our pediatric oncology unit during the pandemic period.

EXPERT OPINION

Starting from the data available in literature, and our experience, showing the rarity of severe COVID-19 disease in pediatric patients with solid tumors, we recommend carefully tailoring all the oncological treatments (chemotherapy/targeted therapy/stem cell transplantation/radiotherapy). The aim is the preservation of the treatment's timing, balanced with an evaluation of possible severe COVID-19 disease.

Expert Consensus: Main Risk Factors for Poor Prognosis in COVID-19 and the Implications for Targeted Measures against SARS-CoV-2

The clinical evolution of patients infected with the Severe Acute Respiratory Coronavirus type 2 (SARS-CoV-2) depends on the complex interplay between viral and host factors. The evolution to less aggressive but better-transmitted viral variants, and the presence of immune memory responses in a growing number of vaccinated and/or virus-exposed individuals, has caused the pandemic to slowly wane in virulence. However, there are still patients with risk factors or comorbidities that put them at risk of poor outcomes in the event of having the coronavirus infectious disease 2019 (COVID-19). Among the different treatment options for patients with COVID-19, virus-targeted measures include antiviral drugs or monoclonal antibodies that may be provided in the early days of infection. The present expert consensus is based on a review of all the literature published between 1 July 2021 and 15 February 2022 that was carried out to establish the characteristics of patients, in terms of presence of risk factors or comorbidities, that may make them candidates for receiving any of the virus-targeted measures available in order to prevent a fatal outcome, such as severe disease or death. A total of 119 studies were included from the review of the literature and 159 were from the additional independent review carried out by the panelists a posteriori. Conditions found related to strong recommendation of the use of virus-targeted measures in the first days of COVID-19 were age above 80 years, or above 65 years with another risk factor; antineoplastic chemotherapy or active malignancy; HIV infection with CD4+ cell counts < 200/mm³; and treatment with anti-CD20 immunosuppressive drugs. There is also a strong recommendation against using the studied interventions in HIV-infected patients with a CD4+ nadir <200/mm³ or treatment with other immunosuppressants. Indications of therapies against SARS-CoV-2, regardless of vaccination status or history of infection, may still exist for some populations, even after COVID-19 has been declared to no longer be a global health emergency by the WHO.

Rethinking immunologic risk: a retrospective cohort study of severe SARS-CoV-2 infections in individuals with congenital immunodeficiencies

Background

Debates on the allocation of medical resources during the COVID-19 pandemic revealed the need for a better understanding of immunologic risk. Studies highlighted variable clinical outcomes of SARS-CoV-2 infections in individuals with defects in both adaptive and innate immunity, suggesting additional contributions from other factors. Notably, none of these studies controlled for variables linked with social determinants of health.

Objective

To determine the contributions of determinants of health to risk of hospitalization for SARS-CoV-2 infection among individuals with inborn errors of immunodeficiencies.

Methods

This is a retrospective, single-center cohort study of 166 individuals with inborn errors of immunity, aged two months through 69 years, who developed SARS-CoV-2 infections from March 1, 2020 through March 31, 2022. Risks of hospitalization was assessed using a multivariable logistic regression analysis.

Results

The risk of SARS-CoV-2-related hospitalization was associated with underrepresented racial and ethnic populations (odds ratio [OR] 5.29; confidence interval [CI], 1.76-17.0), a diagnosis of any genetically-defined immunodeficiency (OR 4.62; CI, 1.60-14.8), use of B cell depleting therapy within one year of infection (OR 6.1; CI, 1.05-38.5), obesity (OR 3.74; CI, 1.17-12.5), and neurologic disease (OR 5.38; CI, 1.61-17.8). COVID-19 vaccination was associated with reduced hospitalization risk (OR 0.52; CI, 0.31-0.81). Defective T cell function, immune-mediated organ dysfunction, and social vulnerability were not associated with increased risk of hospitalization after controlling for covariates.

Conclusions

The associations between race, ethnicity, and obesity with increased risk of hospitalization for SARS-CoV-2 infection indicate the importance of variables linked with social determinants of health as immunologic risk factors for individuals with inborn errors of immunity.

Highlights

What is already known about this topic? Outcomes of SARS-CoV-2 infections in individuals with inborn errors of immunity (IEI) are highly variable. Prior studies of patients with IEI have not controlled for race or social vulnerability. What does this article add to our knowledge ? For individuals with IEI, hospitalizations for SARS-CoV-2 were associated with race, ethnicity, obesity, and neurologic disease. Specific types of immunodeficiency, organ dysfunction, and social vulnerability were not associated with increased risk of hospitalization. How does this study impact current management guidelines? Current guidelines for the management of IEIs focus on risk conferred by genetic and cellular mechanisms. This study highlights the importance of considering variables linked with social determinants of health and common comorbidities as immunologic risk factors.

Immune Responses 6 Months After mRNA-1273 COVID-19 Vaccination and the Effect of a Third Vaccination in Patients with Inborn Errors of Immunity

PURPOSE

Patients with inborn errors of immunity (IEI) are at increased risk of severe coronavirus disease-2019 (COVID-19). Effective long-term protection against COVID-19 is therefore of great importance in these patients, but little is known about the decay of the immune response after primary vaccination. We studied the immune responses 6 months after two mRNA-1273 COVID-19 vaccines in 473 IEI patients and subsequently the response to a third mRNA COVID-19 vaccine in 50 patients with common variable immunodeficiency (CVID).

METHODS

In a prospective multicenter study, 473 IEI patients (including X-linked agammaglobulinemia (XLA) (N = 18), combined immunodeficiency (CID) (N = 22), CVID (N = 203), isolated or undefined antibody deficiencies (N = 204), and phagocyte defects (N = 16)), and 179 controls were included and followed up to 6 months after two doses of the mRNA-1273 COVID-19 vaccine. Additionally, samples were collected from 50 CVID patients who received a third vaccine 6 months after primary vaccination through the national vaccination program. SARS-CoV-2-specific IgG titers, neutralizing antibodies, and T cell responses were assessed.

RESULTS

At 6 months after vaccination, the geometric mean antibody titers (GMT) declined in both IEI patients and healthy controls, when compared to GMT 28 days after vaccination. The trajectory of this decline did not differ between controls and most IEI cohorts; however, antibody titers in CID, CVID, and isolated antibody deficiency patients more often dropped to below the responder cut-off compared to controls. Specific T cell responses were still detectable in 77% of controls and 68% of IEI patients at 6 months post vaccination. A third mRNA vaccine resulted in an antibody response in only two out of 30 CVID patients that did not seroconvert after two mRNA vaccines.

CONCLUSION

A similar decline in IgG titers and T cell responses was observed in patients with IEI when compared to healthy controls 6 months after mRNA-1273 COVID-19 vaccination. The limited beneficial benefit of a third mRNA COVID-19 vaccine in previous non-responder CVID patients implicates that other protective strategies are needed for these vulnerable patients.

Prolonged Disease Course of COVID-19 in a Patient with CTLA-4 Haploinsufficiency

Patients with primary immunodeficiencies are especially vulnerable to developing severe coronavirus disease 2019 (COVID-19) after infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Cytotoxic T lymphocyte antigen-4 (CTLA-4) is an important regulator of immune responses, and patients who suffer from CTLA4 haploinsufficiency have hyperactivation of effector T cells and infiltration of various organs. Overexpression of CTLA4 has been associated with a more severe disease course in patients with COVID-19, but there have only been a few reports on the disease course of COVID-19 in patients with CTLA4 haploinsufficiency. We report on a 33-year-old female with a history of immune thrombocytopenia, autoimmune haemolytic anaemia, granulomatous-lymphocytic interstitial lung disease, and common variable immunodeficiency who developed COVID-19. She was admitted and discharged from the hospital several times in the months thereafter and remained symptomatic and had a positive SARS-CoV-2 PCR for up to 137 days after the first symptoms. No SARS-CoV-2 antibodies were identified in the patients' serum. The disease was finally controlled after repeated infusions of convalescent plasma and treatment of concurrent bacterial and fungal infections. Genetic analysis revealed a likely pathogenic variant in CTLA4, and CTLA4 expression on regulatory T-cells was low. This case illustrates that patients with primary immunodeficiencies who have a protracted disease course of COVID-19 could benefit from convalescent plasma therapy.

Severity Outcomes among Adult Patients with Primary Immunodeficiency and COVID-19 Seen in Emergency Departments, United States, April 2020-August 2021

Primary immunodeficiencies (PIs) are a group of diseases that increase susceptibility to infectious diseases. Few studies have examined the relationship between PI and COVID-19 outcomes. In this study, we used Premier Healthcare Database, which contains information on inpatient discharges, to analyze COVID-19 outcomes among 853 adult PI and 1,197,430 non-PI patients who visited the emergency department. Hospitalization, intensive care unit (ICU) admission, invasive mechanical ventilation (IMV), and death had higher odds in PI patients than in non-PI patients (hospitalization aOR: 2.36, 95% CI: 1.87-2.98; ICU admission aOR: 1.53, 95% CI: 1.19-1.96; IMV aOR: 1.41, 95% CI: 1.15-1.72; death aOR: 1.37, 95% CI: 1.08-1.74), and PI patients spent on average 1.91 more days in the hospital than non-PI patients when adjusted for age, sex, race/ethnicity, and chronic conditions associated with severe COVID-19. Of the largest four PI groups, selective deficiency of the immunoglobulin G subclass had the highest hospitalization frequency (75.2%). This large study of United States PI patients provides real-world evidence that PI is a risk factor for adverse COVID-19 outcomes.

Determinants of COVID-19 Disease Severity-Lessons from Primary and Secondary Immune Disorders including Cancer

At the beginning of the COVID-19 pandemic, patients with primary and secondary immune disorders-including patients suffering from cancer-were generally regarded as a high-risk population in terms of COVID-19 disease severity and mortality. By now, scientific evidence indicates that there is substantial heterogeneity regarding the vulnerability towards COVID-19 in patients with immune disorders. In this review, we aimed to summarize the current knowledge about the effect of coexistent immune disorders on COVID-19 disease severity and vaccination response. In this context, we also regarded cancer as a secondary immune disorder. While patients with hematological malignancies displayed lower seroconversion rates after vaccination in some studies, a majority of cancer patients' risk factors for severe COVID-19 disease were either inherent (such as metastatic or progressive disease) or comparable to the general population (age, male gender and comorbidities such as kidney or liver disease). A deeper understanding is needed to better define patient subgroups at a higher risk for severe COVID-19 disease courses. At the same time, immune disorders as functional disease models offer further insights into the role of specific immune cells and cytokines when orchestrating the immune response towards SARS-CoV-2 infection. Longitudinal serological studies are urgently needed to determine the extent and the duration of SARS-CoV-2 immunity in the general population, as well as immune-compromised and oncological patients.

Persistent SARS-CoV-2 PCR Positivity Despite Anti-viral Treatment in Immunodeficient Patients

PURPOSE

COVID-19 infection in immunodeficient individuals can result in chronically poor health, persistent or relapsing SARS-CoV-2 PCR positivity, and long-term infectious potential. While clinical trials have demonstrated promising outcomes using anti-SARS-CoV-2 medicines in immunocompetent hosts, their ability to achieve sustained viral clearance in immunodeficient patients remains unknown. We therefore aimed to study long-term virological outcomes in patients treated at our centre.

METHODS

We followed up immunocompromised inpatients treated with casirivimab-imdevimab (Ronapreve) between September and December 2021, and immunocompromised patients who received sotrovimab, molnupiravir, nirmatrelvir/ritonavir (Paxlovid), or no treatment from December 2021 to March 2022. Nasopharyngeal swab and sputum samples were obtained either in hospital or in the community until sustained viral clearance, defined as 3 consecutive negative PCR samples, was achieved. Positive samples were sequenced and analysed for mutations of interest.

RESULTS

We observed sustained viral clearance in 71 of 103 patients, none of whom died. Of the 32/103 patients where sustained clearance was not confirmed, 6 died (between 2 and 34 days from treatment). Notably, we observed 25 cases of sputum positivity despite negative nasopharyngeal swab samples, as well as recurrence of SARS-CoV-2 positivity following a negative sample in 12 cases. Patients were then divided into those who cleared within 28 days and those with PCR positivity beyond 28 days. We noted lower B cell counts in the group with persistent PCR positivity (mean (SD) 0.06 (0.10) ×10⁹/L vs 0.22 (0.28) ×10⁹/L, p = 0.015) as well as lower IgA (median (IQR) 0.00 (0.00-0.15) g/L vs 0.40 (0.00-0.95) g/L, p = 0.001) and IgM (median (IQR) 0.05 (0.00-0.28) g/L vs 0.35 (0.10-1.10) g/L, p = 0.005). No differences were seen in CD4+ or CD8+ T cell counts. Antiviral treatment did not impact risk of persistent PCR positivity.

CONCLUSION

Persistent SARS-CoV-2 PCR positivity is common among immunodeficient individuals, especially those with antibody deficiencies, regardless of anti-viral treatment. Peripheral B cell count and serum IgA and IgM levels are predictors of viral persistence.

Detection of specific RBD+ IgG+ memory B cells by flow cytometry in healthcare workers and patients with inborn errors of immunity after BNT162b2 m RNA COVID-19 vaccination

Introduction

Inborn errors of immunity (IEI) are a heterogeneous group of diseases caused by intrinsic defects of the immune system. Estimating the immune competence of immunocompromised patients for an infection risk assessment or after SARS-CoV-2 vaccination constituted a challenge.

Methods

The aim of this study was to determine the humoral responses of patients with IEI through a comprehensive analysis of specific receptor-binding domain-positive (RBD+) IgG+ memory B cells (MBCs) by flow cytometry, together with routine S-specific IgG antibodies and QuantiFERON SARS-CoV-2 (T-cell response), before the vaccine and 3 weeks after a second dose.

Results and discussion

We first analyzed the percentage of specific RBD+ IgG+ MBCs in healthy healthcare workers. Within the control group, there was an increase in the percentage of specific IgG+ RBD+ MBCs 21 days after the second dose, which was consistent with S-specific IgG antibodies.Thirty-one patients with IEI were included for the pre- and post-vaccination study; IgG+ RBD+ MBCs were not evaluated in 6 patients due to an absence of B cells in peripheral blood. We detected various patterns among the patients with IEI with circulating B cells (25, 81%): an adequate humoral response was observed in 12/25, consider by the detection of positive S-specific IgG antibodies and the presence of specific IgG+ RBD+ MBCs, presenting a positive T-cell response; in 4/25, very low S-specific IgG antibody counts correlated with undetectable events in the IgG+ RBD+ MBC compartment but with positive cellular response. Despite the presence of S-specific IgG antibodies, we were unable to detect a relevant percentage of IgG+ RBD+ MBCs in 5/25; however, all presented positive T-cell response. Lastly, we observed a profound failure of B and T-cell response in 3 (10%) patients with IEI, with no assessment of S-specific IgG antibodies, IgG+ RBD+ MBCs, and negative cellular response. The identification of specific IgG+ RBD+ MBCs by flow cytometry provides information on different humoral immune response outcomes in patients with IEI and aids the assessment of immune competence status after SARS-CoV-2 mRNA vaccine (BNT162b2), together with S-specific IgG antibodies and T-cell responses.

Safety and tolerability of Evusheld in patients with CVID: The Mayo Clinic experience

BACKGROUND

The past 2 years of the COVID-19 pandemic brought with it many unknowns for patients with immunodeficiency. Because of the concern for severe infection in those with immunocompromise, patients have been eager for effective prevention, vaccination, and treatment strategies. Preexposure prophylaxis provides another means of prevention in those with immunocompromise. A combination of tixagevimab and cilgavimab (Evusheld [AstraZeneca Cambridge, United Kingdom]) was granted emergency use authorization for preexposure prophylaxis at the end of 2021, but questions remained regarding how this would be tolerated and the side effects associated with its use.

OBJECTIVES

Our aim was to evaluate the safety and tolerability of Evusheld in patients with CVID from our tri-site institution.

METHODS

We performed an institutional review board-approved, retrospective chart review of patients with common variable immunodeficiency (CVID) who received Evusheld before March 26, 2022.

RESULTS

Of the 45 patients with CVID who received Evusheld, 41 (91%) received the recommended full dose of 600 mg. The majority of patients (39 of 45 [87%]) tolerated Evusheld without adverse events. The adverse events reported included immediate injection site pain, fatigue and cough, an episode of shingles, and chest pain.

CONCLUSIONS

This is an initial report on the safety and tolerability of Evusheld injections in patients with CVID. The majority of patients tolerated the injections without adverse events. For patients with reported chest pain, the results of a subsequent cardiac workup were negative. The efficacy of Evusheld could not be evaluated owing to the short median follow-up of this study (19 days).

Extracorporeal Membrane Oxygenation in Children With COVID-19: A Systematic Review and Meta-Analysis

OBJECTIVES

The indication, complications, and outcomes of extracorporeal membrane oxygenation (ECMO) in children with COVID-19-related illnesses remain unelucidated. Our study aimed to investigate the characteristics and outcomes of ECMO in children with COVID-19-related illnesses.

DATA SOURCES

We searched PubMed and EMBASE databases in March 2022.

STUDY SELECTION

We retrieved all studies involving children (age ≤ 18 yr) with COVID-19-related illnesses who received ECMO.

DATA EXTRACTION

Two authors independently extracted data and assessed the risk of bias. Mortality, successful weaning rate, and complications while on ECMO were synthesized by a one-group meta-analysis using a random-effect model. Meta-regression was performed to explore the risk factors for mortality.

DATA SYNTHESIS

We included 18 observational studies, four case series, and 22 case reports involving 110 children with COVID-19-related illnesses receiving ECMO. The median age was 8 years (range, 10 d to 18 yr), and the median body mass index was 21.4 kg/m 2 (range, 12.3-56.0 kg/m 2 ). The most common comorbidities were obesity (11% [7/63]) and congenital heart disease (11% [7/63]), whereas 48% (30/63) were previously healthy. The most common indications for ECMO were multisystem inflammatory syndrome in children (52% [47/90]) and severe acute respiratory distress syndrome (40% [36/90]). Seventy-one percent (56/79) received venoarterial-ECMO. The median ECMO runtime was 6 days (range, 3-51 d) for venoarterial ECMO and 11 days (range, 3-71 d) for venovenous ECMO. The mortality was 26.6% (95% CI, 15.9-40.9), and the successful weaning rate was 77.0% (95% CI, 55.4-90.1). Complications were seen in 37.0% (95% CI, 23.1-53.5) while on ECMO, including stroke, acute kidney injury, pulmonary edema, and thromboembolism. Corticosteroids and IV immunoglobulin therapies were associated with lower mortality.

CONCLUSIONS

The mortality of children on ECMO for COVID-19 was relatively low. This invasive treatment can be considered as a treatment option for critically ill children with COVID-19.

Successful Combination of Remdesivir and Convalescent Plasma to Treat a Patient with Rituximab-Related B-Cell Deficiency and Prolonged COVID-19: A Case Report

Background:

Treatment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in immuno-compromised patients with complete B cell depletion can be really challenging due to the lack of seroconversion and long-lasting disease.

Case Report:

We describe a case of long-lasting coronavirus disease (COVID-19) in a female patient with rheumatoid arthritis who was treated with rituximab and continued to show B-cell depletion. An ongoing replication of SARS-CoV-2 was demonstrated for a period of 8 months when nasopharyngeal swabs were tested. She was treated once with remdesivir but without lasting resolution, and she was then treated with convalescent plasma but with a similar effect. Only with a combination of both treatments was clinical resolution achieved. The patient's lack of seroconversion and the prolonged course of the disease illustrate the importance of humoral immunity in resolving SARS-CoV-2 infection. This case report highlights challenges in managing immunocompromised hosts, who may act as persistent shedders and sources of transmission.

Conclusions:

The combination of remdesivir and convalescent plasma resulted in successfully achieving clinical resolution of SARS-CoV-2 infection in our patient.

Inherited and acquired errors of type I interferon immunity govern susceptibility to COVID-19 and multisystem inflammatory syndrome in children

Since the beginning of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)/coronavirus disease 2019 (COVID-19) pandemic, global sequencing efforts have led in the field of inborn errors of immunity, and inspired particularly by previous research on life-threatening influenza, they have revealed that known and novel inborn errors affecting type I interferon immunity underlie critical COVID-19 in up to 5% of cases. In addition, neutralizing autoantibodies against type I interferons have been identified in up to 20% of patients with critical COVID-19 who are older than 80 years and 20% of fatal cases, with a higher prevalence in men and individuals older than 70 years. Also, inborn errors impairing regulation of type I interferon responses and RNA degradation have been found as causes of multisystem inflammatory syndrome in children, a life-threatening hyperinflammatory condition complicating otherwise mild initial SARS-CoV-2 infection in children and young adults. Better understanding of these immunologic mechanisms can aid in designing treatments for severe COVID-19, multisystem inflammatory syndrome in children, long COVID, and neuro-COVID.

Impact of SARS-CoV-2 infection and COVID-19 on patients with inborn errors of immunity

Since the arrival of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in December 2019, its characterization as a novel human pathogen, and the resulting coronavirus disease 2019 (COVID-19) pandemic, over 6.5 million people have died worldwide-a stark and sobering reminder of the fundamental and nonredundant roles of the innate and adaptive immune systems in host defense against emerging pathogens. Inborn errors of immunity (IEI) are caused by germline variants, typically in single genes. IEI are characterized by defects in development and/or function of cells involved in immunity and host defense, rendering individuals highly susceptible to severe, recurrent, and sometimes fatal infections, as well as immune dysregulatory conditions such as autoinflammation, autoimmunity, and allergy. The study of IEI has revealed key insights into the molecular and cellular requirements for immune-mediated protection against infectious diseases. Indeed, this has been exemplified by assessing the impact of SARS-CoV-2 infection in individuals with previously diagnosed IEI, as well as analyzing rare cases of severe COVID-19 in otherwise healthy individuals. This approach has defined fundamental aspects of mechanisms of disease pathogenesis, immunopathology in the context of infection with a novel pathogen, and therapeutic options to mitigate severe disease. This review summarizes these findings and illustrates how the study of these rare experiments of nature can inform key features of human immunology, which can then be leveraged to improve therapies for treating emerging and established infectious diseases.

NFKB2 haploinsufficiency identified via screening for IFN-α2 autoantibodies in children and adolescents hospitalized with SARS-CoV-2-related complications

BACKGROUND

Autoantibodies against type I IFNs occur in approximately 10% of adults with life-threatening coronavirus disease 2019 (COVID-19). The frequency of anti-IFN autoantibodies in children with severe sequelae of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is unknown.

OBJECTIVE

We quantified anti-type I IFN autoantibodies in a multicenter cohort of children with severe COVID-19, multisystem inflammatory syndrome in children (MIS-C), and mild SARS-CoV-2 infections.

METHODS

Circulating anti-IFN-α2 antibodies were measured by a radioligand binding assay. Whole-exome sequencing, RNA sequencing, and functional studies of peripheral blood mononuclear cells were used to study any patients with levels of anti-IFN-α2 autoantibodies exceeding the assay's positive control.

RESULTS

Among 168 patients with severe COVID-19, 199 with MIS-C, and 45 with mild SARS-CoV-2 infections, only 1 had high levels of anti-IFN-α2 antibodies. Anti-IFN-α2 autoantibodies were not detected in patients treated with intravenous immunoglobulin before sample collection. Whole-exome sequencing identified a missense variant in the ankyrin domain of NFKB2, encoding the p100 subunit of nuclear factor kappa-light-chain enhancer of activated B cells, aka NF-κB, essential for noncanonical NF-κB signaling. The patient's peripheral blood mononuclear cells exhibited impaired cleavage of p100 characteristic of NFKB2 haploinsufficiency, an inborn error of immunity with a high prevalence of autoimmunity.

CONCLUSIONS

High levels of anti-IFN-α2 autoantibodies in children and adolescents with MIS-C, severe COVID-19, and mild SARS-CoV-2 infections are rare but can occur in patients with inborn errors of immunity.

SARS-CoV-2 spike antibody concentration in gamma globulin products from high-prevalence COVID-19 countries are transmitted to X-linked agammaglobulinemia patients

Purpose

Patients with X-linked agammaglobulinemia (XLA) are characterized by humoral impairment and are routinely treated with intravenous immunoglobulin (IVIG). In this study, we aimed to investigate the presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in IVIG preparations harvested globally and evaluate the transfer of SARS-CoV-2 antibodies to the XLA patient.

Methods

A single-center, prospective cohort study was conducted in the period of November 2020 to November 2022. Clinical and laboratory data, specifically, SARS-CoV-2 spike IgG levels from the serum of 115 IVIG preparations given to 5 XLA patient were collected. Concurrently, SARS-CoV-2 spike IgG levels from the serum of the 5 XLA was collected monthly.

Results

Five XLA patients were evaluated within the study period. All were treated monthly with commercial IVIG preparations. A total of 115 IVIG treatments were given over the study period. The origin country and the date of IVIG harvesting was obtained for 111 (96%) of the treatments. Fifty-four IVIG preparations (49%) were harvested during the COVID-19 pandemic of which 76% were positive (&gt;50AU/mL) for SARS-CoV-2 spike antibodies which were subsequently transmitted to the XLA patients in an approximate 10-fold reduction. SARS-CoV2 spike IgG was first detected in IVIG batches that completed their harvest date by September 2021. Positive products were harvested from origin countries with a documented prevalence over 2,000 per 100,000 population.

Conclusion

As the prevalence of COVID-19 infections rises, detection of SARS-CoV-2 spike IgG in commercial IVIG products increases and is then transmitted to the patient. Future studies are needed to investigate the neutralizing capabilities of SARS-CoV-2 IgG and whether titer levels in IVIG remain consistent as the incidence of infection and vaccination rates in the population changes.