Adapting REDCap for COVID-19 Laboratory Data Management in Botswana - Experiences, Lessons and Challenges (preprint)

Background The COVID-19 pandemic brought challenges requiring timely health data sharing to inform decision making on appropriate interventions at a national level. To streamline the collection and integration of data, we designed and piloted a workflow utilizing the REDCap platform. Our approach focused on establishing efficient COVID-19 data flows within a national public health laboratory, enabling seamless integration with the national district health information management system (DHIS2). This integration facilitated an automated centralized reporting of COVID-19 results at the Ministry of Health. This paper reports the experiences, challenges and lessons learnt while designing, adapting, and implementing REDCap to support COVID-19 data management at the National Health Lab in Botswana. Methods A participatory design approach was adopted to guide the design, customization, and implementation of the REDCap platform in support of COVID-19 data management at the NHL. Twenty-nine NHL and four Ministry of Health personnel participated in the study, effective from 02 March 2020 to 30 June 2020. Participants’ requirements for an ideal COVID-19 data management system were established. NVivo 11 software supported thematic analysis of the challenges and resolutions identified during this study. These were categorized according to four themes of Infrastructure, Capacity Development, Platform constraints, and Interoperability. Results Overall, REDCap supported a majority of perceived technical and non-technical requirements for an ideal COVID-19 data management system at the NHL. Although some implementation challenges were identified, each had mitigation strategies such as procurement of mobile internet routers, engagement of senior management to resolve conflicting policies, continuous REDCap training, and the development of a third-party web application to enhance REDCap’s capabilities. Lessons learnt informed next steps and further refinement of the REDCap platform. Conclusion Implementation of REDCap at the NHL to streamline COVID-19 data collection and integration with national systems was feasible despite its emergency implementation during the pandemic. By piloting and implementing the REDCap workflow at a national public health laboratory, we demonstrated feasibility for centralized reporting of COVID-19 cases, enabling timely and informed decision-making at the national level. Challenges faced presented lessons learnt to inform sustainable implementation of digital health innovations in a resource-constrained environment.

Blood cancer in children infected with COVID-19: A comprehensive systematic review (preprint)

Background: Blood cancer is the most common type of cancer and the leading cause of death by disease past infancy among children. Children with blood cancer are vulnerable population to viral infections such as coronavirus disease 2019 (COVID-19). Objectives: To estimate the incidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in blood cancer children and analyse the demographic parameters, clinical characteristics and treatment outcomes in blood cancer children 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 blood cancer, published from December 1, 2019 to April 30, 2023, with English language restriction. Results: Of the 3077 papers that were identified, 155 articles were included in the systematic review (83 case report, 54 cohort and 18 case-series studies). Studies involving 1289 blood cancer children with confirmed COVID-19 were analysed. Leukaemias (1141 cases) were the most frequent types of blood cancer observed in children who developed COVID-19, followed by non-Hodgkin’s lymphomas (59 cases), Hodgkin’s lymphomas (36 cases), Langerhans cell histiocytosis (7 cases), myelodysplastic syndrome (7 cases) and myeloid neoplasm (1 case). Among all 1289 blood cancer paediatric cases who transmitted SARS-CoV-2, some children were documented to be admitted to the intensive care unit (ICU) (n = 175, 13.6%), intubated and placed on mechanical ventilation (n = 111, 8.6%), suffered acute respiratory distress syndrome (n = 144, 11.2%) or died (n = 111, 8.6%). Overall, COVID-19 in children with different types of blood cancer resulted in no or low severity of disease in more than 78.6% of all included cases (COVID-19 severity: asymptomatic = 239, mild = 603, or moderate = 171). Treatment for COVID-19 was not necessary in a high number of blood cancer children (n = 94, 7.3%). Fatality in blood cancer children with COVID-19 was reported in any of the included blood cancer categories for leukaemias (n = 99, 8.7%), non-Hodgkin’s lymphomas (n = 7, 11.9%), Hodgkin’s lymphomas (n = 2, 5.5%), myelodysplastic syndrome (n = 1, 14.3%) or myeloid neoplasm (n = 1, 100%). Fatality rate in blood cancer children infected with SARS-CoV-2 was the highest in patients with Hispanic ethnicity (n = 44/111, 39.6%) and COVID-19–related fatality was highest in male patients (76.5% of deceased patients). Most studies reported to alter the intensity and regimen of anticancer treatment in blood cancer children during course of SARS-CoV-2 infection, however, many studies have reported to successfully treat COVID-19 without any changes to the anticancer treatment. Conclusion: Globally, leukaemias were the most prevalent and myeloid neoplasms were the least prevalent blood cancer types in children who developed SARS-CoV-2 infection. Children with blood cancer tend to have milder COVID-19 symptoms and are less likely to be hospitalized and have better prognosis when compared to adults. Continuation of anticancer treatment in individual paediatric blood cancer patients with COVID-19 seems to be possible.

Response to COVID-19 Vaccination Post-CAR T Therapy in Patients With Non-Hodgkin Lymphoma and Multiple Myeloma.

COVID-19 adversely affects individuals with cancer. Several studies have found that seroconversion rates among patients with hematologic malignancies are suboptimal when compared to patients without cancer. Patients with non-Hodgkin lymphoma (NHL) and multiple myeloma (MM) are immunocompromised due to impaired humoral and cellular immunity in addition to prescribed immunosuppressive therapy. Chimeric antigen receptor T-cell (CAR T) therapy is now widely used for NHL and MM, but little is known about seroconversion rates after COVID-19 vaccination among these populations. We evaluated SARS-CoV-2 spike-binding IgG antibody levels following COVID-19 vaccination among NHL and MM CAR T therapy recipients. Out of 104 CAR T infusions, 19 patients developed known COVID-19 infection post-CAR T. We tested 17 patients that received CAR T for antibody spike titers post COVID-19 vaccination, only 29 % (n = 5) were able to mount a clinically relevant antibody response (>250 IU/mL).

Bendamustine and rituximab is well-tolerated and efficient in the treatment of indolent non-Hodgkin's lymphoma and mantle cell lymphoma in elderly: A single center observational study.

Bendamustine and rituximab (BR) is a preferred first-line therapy for indolent non-Hodgkin's lymphoma (iNHL) and mantle cell lymphoma (MCL); however, few reports on BR performance in elderly patients are available to date. We compared safety and efficacy of BR in patients ≥70 years (elderly) vs <70 years (younger) treated at our institution. Among 201 patients, 113 were elderly (median age: 77 years), including 38 patients ≥80 years, and 88 were younger (median age: 62 years). Elderly patients had more bone marrow involvement by lymphoma, anemia, ECOG status 3 and high-risk disease follicular lymphoma (P < .05 for all). Fifty-four percent of elderly received full dose of bendamustine vs 79.5% of younger patients. More elderly patients (54%) vs younger (43.2%) experienced treatment delay. Less elderly proceeded to rituximab maintenance. Overall, the number of adverse events per patient and transformed B-Cell lymphoma/secondary malignancies were similar between groups. Elderly patients had less febrile neutropenia, rituximab-associated infusion reactions, but more herpes zoster reactivation. There were more deaths in the elderly (37.2%) vs younger (10.2%) groups (P < .001), mainly due to non-lymphoma-related causes. With median follow-up of 42 months [4.0-97.0] disease-free survival for the elderly was similar to younger patients. There was no difference between patients <80 and ≥80 years (P = .274). In conclusion, the real-world elderly patients have more advanced disease and higher ECOG status. BR is well-tolerated; elderly patients had lower incidence of febrile neutropenia. Dose reduction and treatment delays are common, but BR efficacy was not affected even in very old patients (≥80 years).

COVID-19 and non-Hodgkin's lymphoma: A common susceptibility pattern?

OBJECTIVE: To explore the link between COVID-19 incidence, socio-economic covariates, and NHL incidence. DESIGN: Ecological study design. SETTING: Sardinia, Italy. PARTICIPANTS: We used official reports on the total cases of COVID-19 in 2020, published data on NHL incidence, and socio-economic indicators by administrative unit, covering the whole regional population. MAIN OUTCOMES AND MEASURES: We used multivariable regression analysis to explore the association between the natural logarithm (ln) of the 2020 cumulative incidence of COVID-19 and the ln-transformed NHL incidence in 1974-2003, weighing by population size and adjusting by socioeconomic deprivation and other covariates. RESULTS: The cumulative incidence of COVID-19 increased in relation to past incidence of NHL (p < 0.001), socioeconomic deprivation (p = 0.006), and proportion of elderly residents (p < 0.001) and decreased with urban residency (p = 0.001). Several sensitivity analyses confirmed the finding of an association between COVID-19 and NHL. CONCLUSION: This ecological study found an ecological association between NHL and COVID-19. If further investigation would confirm our findings, shared susceptibility factors should be investigated among the plausible underlying mechanisms.

No association of malignant B-cell non-Hodgkin lymphomas with ipsilateral SARS-CoV-2 vaccination.

PURPOSE: SARS-CoV-2 vaccines cause acute ipsilateral lymph node swelling in an important proportion of vaccines. Thus far, no malignant lymphadenopathies have been reported in temporal context to vaccination in the ipsilateral draining lymph node areas. EXPERIMENTAL DESIGN: Prompted by two cases with unilateral axillary lymphomas that occurred ipsilaterally to prior SARS-CoV-2 vaccination, we systematically retrieved all B-cell non-Hodgkin lymphomas at two German University Medical Centers diagnosed before and after introduction of SARS-CoV-2 vaccines in Germany. Available lymphoma tissue (n=19) was subjected to next-generation immunosequencing of the IGH locus. Malignant clonotypes were mined in the CoVabDab database and published data sets from 342 uninfected individuals, 55 individuals 28 days after anti-SARS-CoV-2 vaccination and 139 individuals with acute COVID-19 together encompassing over 1 million CDR3 sequences in total. RESULTS: Of 313 newly diagnosed cases in the two centers and observation periods, 27 unilateral manifestations in the defined deltoid draining regions were identified. The majority thereof were diffuse large B-cell lymphomas (18 of 27 cases). Eleven unilateral cases were diagnosed in the era of SARS-CoV-2 vaccination and 16 in the control period before introduction of such vaccines. Of the 11 unilateral lymphomas that occurred during the vaccination period, ten had received a SARS-CoV-2 vaccine prior to lymphoma diagnosis. These cases were further evaluated. While left-sided were more frequent than right-sided lymphomas (19 vs 8 cases), no statistically significant association of vaccination site and laterality of the lymphoma manifestation was found. The unilateral lymphomas showed a normal range of B-cell receptors typically found in these lymphoma subtypes with no evidence for anti-SARS-CoV-2 sequences in the malignant clonotype. CONCLUSIONS: Together, we found no evidence that the current SARS-CoV-2 vaccines could serve as a trigger for lymphomagenesis in the draining lymph node areas of the deltoid region used for vaccination.

SARS-CoV-2 Genome Variations in Viral Shedding of an Immunocompromised Patient with Non-Hodgkin's Lymphoma.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing coronavirus disease 2019 (COVID-19) is the most transmissible ß-coronavirus in history, affecting all population groups. Immunocompromised patients, particularly cancer patients, have been highlighted as a reservoir to promote accumulation of viral mutations throughout persistent infection. CASE PRESENTATION: We aimed to describe the clinical course and SARS-CoV-2 mutation profile for 102 days in an immunocompromised patient with non-Hodgkin's lymphoma and COVID-19. We used RT-qPCR to quantify SARS-CoV-2 viral load over time and whole-virus genome sequencing to identify viral lineage and mutation profile. The patient presented with a persistent infection through 102 days while being treated with cytotoxic chemotherapy for non-Hodgkin's lymphoma and received targeted therapy for COVID-19 with remdesivir and hyperimmune plasma. All sequenced samples belonged to the BA.1.1 lineage. We detected nine amino acid substitutions in five viral genes (Nucleocapsid, ORF1a, ORF1b, ORF13a, and ORF9b), grouped in two clusters: the first cluster with amino acid substitutions only detected on days 39 and 87 of sample collection, and the second cluster with amino acid substitutions only detected on day 95 of sample collection. The Spike gene remained unchanged in all samples. Viral load was dynamic but consistent with the disease flares. CONCLUSIONS: This report shows that the multiple mutations that occur in an immunocompromised patient with persistent COVID-19 could provide information regarding viral evolution and emergence of new SARS-CoV-2 variants.

Expression of MicroRNA-155 in Patients with Non-Hodgkin Lymphoma, Coronavirus Disease 2019, or Both: A Cross-Sectional Study.

Background: Non-Hodgkin lymphoma (NHL) is the eleventh leading cause of cancer-related death in the world. Diffuse large B-cell lymphoma (DLBCL) is the most common type of NHL. Up to winter 2021-2022, the death toll caused by the coronavirus disease 2019 (COVID-19) has exceeded 5.6 million worldwide. Possible molecular mechanisms involved in the systemic inflammation, and cytokine storm in COVID-19 patients are still not fully understood. MicroRNA-155 (miR-155) plays a role in the post-transcriptional gene regulation of hematopoiesis, oncogenesis, and inflammation. The present study aimed to evaluate the expression of miR-155 in patients with DLBCL and/or COVID-19. Methods: A cross-sectional study was conducted from July to December 2020 in Tehran (Iran) to evaluate the expression of miR-155 in adult patients diagnosed with DLBCL and/or COVID-19. The real-time polymerase chain reaction technique was used to evaluate the expression of miR-155 in the sera of 92 adults who were either healthy or suffering from DLBCL and/or COVID-19. Relative quantification of gene expression was calculated in terms of cycle threshold (Ct) value. Data were analyzed using SPSS software, and P<0.05 was considered statistically significant. Results: The expression of miR-155 was not associated with the sex or age of the participants. In comparison with healthy individuals (-ΔCt -1.92±0.25), the expression of miR-155 increased in patients with COVID-19 (1.95±0.14), DLBCL (2.25±0.16), or both (4.33±0.65). Conclusion: The expression of miR-155 increased in patients with DLBCL and/or COVID-19.

COVID-19 and non-Hodgkins lymphoma: a common susceptibility pattern? (preprint)

Objective To explore the link between COVID-19 incidence, socio-economic covariates, and NHL incidence. Design Ecological study design. Setting Sardinia, Italy. Participants We used official reports on the total cases of COVID-19 in 2020, published data on NHL incidence, and socio-economic indicators by administrative unit, covering the whole regional population. Main outcomes and measures We used multivariable regression analysis to explore the association between the natural logarithm (ln) of the 2020 cumulative incidence of COVID-19 and the ln-transformed NHL incidence in 1974-2003, weighing by population size and adjusting by socioeconomic deprivation and other covariates. Results The cumulative incidence of COVID-19 increased in relation to past incidence of NHL (p < 0.001), socioeconomic deprivation (p = 0.006), and proportion of elderly residents (p < 0.001) and decreased with urban residency (p = 0.001). Several sensitivity analyses confirmed the finding of an association between COVID-19 and NHL. Conclusion This ecological study found an ecological association between NHL and COVID-19. If further investigation would confirm our findings, shared susceptibility factors should be investigated among the plausible underlying mechanisms.

Early Side Effects after Administration of the 1st Dose of Oxford-AstraZeneca Vaccine (preprint)

Vaccines have played a central role in minimizing new infections, the rate of hospitalizations, and the overall burden on the health sector. Fear of side effects is the biggest and commonest reason for avoiding getting vaccinated. It is, therefore, essential to maintain the clarity and consistency of message, to support and encourage people to get vaccinated. This study aims to contribute in that regard, by registering and quantifying the early side-effects of the Oxford-AstraZeneca COVID-19 vaccine in Pakistan. This study employs a non-random cross-sectional design. Data collected from 477 participants using a structured questionnaire was used to investigate the relationship between socio-demographic characteristics and side effect profiles of the participants. Binomial Logistic Regression was used to analyze the data. Odds Ratio (OR) gives the likelihood of having a side effect versus the reference group. Significance level () for the probability value (p-value) is set at 0.05. Fever (30.19%) was the most commonly experienced side effect, followed closely by fatigue (22.01%). 71.11% of those with fever experienced low grade fever (99-100F) while 62.69% of body aches experienced were moderate in intensity (Grades 4-6). In general, younger people are significantly more likely (p=0.023) to experience side effects (OR -1 = 1.023: interpreted as 1.023 times increase per unit decrease in age). Similarly, they are more likely (p= 0.029) to have a headache (OR -1 =1.039). Also, they are more likely (p= 0.007) to have a body ache (OR -1 =1.038). The Oxford-AstraZeneca COVID-19 vaccine side-effects seem to be more prevalent among younger age groups, which points to increased vaccine safety among older individuals that are usually more susceptible to severe COVID-19 infection. In addition, we found a substantially reduced number of side-effects, as compared to the clinical trials, which is an encouraging indicator for vaccine safety.

Humoral Responses Against SARS-CoV-2 and Variants of Concern After mRNA Vaccines in Patients With Non-Hodgkin Lymphoma and Chronic Lymphocytic Leukemia.

PURPOSE: Patients with non-Hodgkin lymphoma including chronic lymphocytic leukemia (NHL/CLL) are at higher risk of severe SARS-CoV-2 infection. We investigated vaccine-induced antibody responses in patients with NHL/CLL against the original SARS-CoV-2 strain and variants of concern including B.1.167.2 (Delta) and B.1.1.529 (Omicron). MATERIALS AND METHODS: Blood from 121 patients with NHL/CLL receiving two doses of vaccine were collected longitudinally. Antibody binding against the full-length spike protein, the receptor-binding, and N-terminal domains of the original strain and of variants was measured using a multiplex assay. Live-virus neutralization against Delta, Omicron, and the early WA1/2020 strains was measured using a focus reduction neutralization test. B cells were measured by flow cytometry. Correlation between vaccine response and clinical factors was determined. RESULTS: Mean anti-SARS-CoV-2 spike immunoglobulin G-binding titers were 85-fold lower in patients with NHL/CLL compared with healthy controls, with seroconversion occurring in only 67% of patients. Neutralization titers were also lower and correlated with binding titers (P < .0001). Treatment with anti-CD20-directed therapies within 1 year resulted in 136-fold lower binding titers. Peripheral blood B-cell count also correlated with vaccine response. At 3 months from last anti-CD20-directed therapy, B-cell count ≥ 4.31/µL blood around the time of vaccination predicted response (OR 7.46, P = .04). Antibody responses also correlated with age. Importantly, neutralization titers against Delta and Omicron were reduced six- and 42-fold, respectively, with 67% of patients seropositive for WA1/2020 exhibiting seronegativity for Omicron. CONCLUSION: Antibody binding and live-virus neutralization against SARS-CoV-2 and its variants of concern including Delta and Omicron were substantially lower in patients with NHL/CLL compared with healthy vaccinees. Anti-CD20-directed therapy < 1 year before vaccination and number of circulating B cells strongly predict vaccine response.

Characteristics of Patients with Hematologic Malignancies Without Seroconversion Post-COVID19 Third Vaccine Dosing (preprint)

Patients with hematologic malignancies (HM) are at greater risk of severe morbidity and mortality caused by COVID19 and show a lower response to a two-dose COVID19 mRNA vaccine series. The primary objective of this retrospective cohort study is to explore the characteristics of the subset of patients with HM who had little to no change in SARS-CoV-2 spike antibody titer levels after a 3rd vaccine dose (3V) (-/-). As a secondary objective, we seek to compare the cohorts of patients who did and did not seroconvert post-3V to get a better understanding of the demographics and potential drivers of serostatus. A total of 625 patients with HM had two titer results at least 21 days apart pre- and post- the 3V dose. Among the participants who were seronegative prior to 3V (268), 149 (55.6%) seroconverted after the 3V dose and 119 (44.4%) did not. HM diagnosis was significantly associated with seroconversion status (P = .0003) with patients non-Hodgkin lymphoma 6 times the odds of not seroconverting compared to multiple myeloma patients (P = .0010). Among the cohort of patients who remained seronegative post-3V, 107 (90.0%) patients showed no reaction to 3V as indicated by pre- and post- 3V index values. This study focuses on an important subset of patients with HM who are not seroconverting after the COVID mRNA 3V, providing much needed data for clinicians to target and counsel this subset of patients.

COVID-19 mRNA Vaccine in Patients With Lymphoid Malignancy or Anti-CD20 Antibody Therapy: A Systematic Review and Meta-Analysis.

BACKGROUND: The humoral response to vaccination in individuals with lymphoid malignancies or those undergoing anti-CD20 antibody therapy is impaired, but details of the response to mRNA vaccines to protect against COVID-19 remain unclear. This systematic review and meta-analysis aimed to characterize the response to COVID-19 mRNA vaccines in patients with lymphoid malignancies or those undergoing anti-CD20 antibody therapy. MATERIALS AND METHODS: A literature search retrieved 52 relevant articles, and random-effect models were used to analyze humoral and cellular responses. RESULTS: Lymphoid malignancies and anti-CD20 antibody therapy for non-malignancies were significantly associated with lower seropositivity rates (risk ratio 0.60 [95% CI 0.53-0.69]; risk ratio 0.45 [95% CI 0.39-0.52], respectively). Some subtypes (chronic lymphocytic leukemia, treatment-naïve chronic lymphocytic leukemia, myeloma, and non-Hodgkin's lymphoma) exhibited impaired humoral response. Anti-CD20 antibody therapy within 6 months of vaccination decreased humoral response; moreover, therapy > 12 months before vaccination still impaired the humoral response. However, anti-CD20 antibody therapy in non-malignant patients did not attenuate T cell responses. CONCLUSION: These data suggest that patients with lymphoid malignancies or those undergoing anti-CD20 antibody therapy experience an impaired humoral response, but cellular response can be detected independent of anti-CD20 antibody therapy. Studies with long-term follow-up of vaccine effectiveness are warranted (PROSPERO registration number: CRD42021265780).

BNT162b2 mRNA COVID-19 vaccine booster induces seroconversion in patients with B-cell non-Hodgkin lymphoma who failed to respond to two prior vaccine doses.

This prospective study evaluated seroconversion rates in response to BNT162b2 (Pfizer-BioNTech) COVID-19 vaccine booster in 44 B-cell non-Hodgkin lymphoma (B-NHL) patients who failed to respond to two prior doses [42 previously exposed to anti-CD20 monoclonal antibodies (moAbs) including 13 under maintenance treatment]. Seroconversion was obtained in 29.5% of the patients. Longer time from last anti-CD20 moAb (>6 months) and diagnosis of aggressive lymphoma compared to other, incurable B-NHLs were associated with increased seroconversion rates (47.8% vs.10.5%, p = 0.019 and 50% vs. 17.9%, p = 0.025 respectively). Thus, seronegative patients with B-NHL that completed anti-CD20 therapy more than 6 months prior to the booster have greater chances to achieve seroconversion.

SARS-CoV-2 Slows Brain Rhythms with more Severe Effects in Younger Individuals (preprint)

Coronavirus disease secondary to infection by SARS-CoV-2 (COVID19 or C19) causes respiratory illness, as well as severe neurological symptoms that have not been fully characterized. In a previous study, we developed a computational pipeline for the automated, rapid, high-throughput and objective analysis of brain encephalography (EEG) rhythms. In this retrospective study, we used this pipeline to define the quantitative EEG changes in patients with a PCR-positive diagnosis of C19 (n=31) in the intensive care unit (ICU) of Cleveland Clinic, compared to a group of age-matched PCR-negative (n=38) control patients in the same ICU setting. Qualitative assessment of EEG by two independent teams of electroencephalographers confirmed prior reports with regards to the high prevalence of diffuse encephalopathy in C19 patients, although the diagnosis of encephalopathy was inconsistent between teams. Quantitative analysis of EEG showed distinct slowing of brain rhythms in C19 patients compared to control (enhanced delta power and attenuated alpha-beta power). Surprisingly, these C19-related changes in EEG power were more prominent in patients below age 70. Moreover, machine learning algorithms showed consistently higher accuracy in the binary classification of patients as C19 versus control using EEG power for subjects below age 70 compared to older ones, providing further evidence for the more severe impact of SARS-CoV-2 on brain rhythms in younger individuals irrespective of PCR diagnosis or symptomatology, and raising concerns over potential long-term effects of C19 on brain physiology in the adult population and the utility of EEG monitoring in C19 patients.

Anti-CD20 monoclonal antibodies inhibit seropositive response to Covid-19 vaccination in non-Hodgkin lymphoma patients within 6 months after treatment.

The Covid-19 pandemic has caused millions of deaths worldwide. Although vaccines have been developed, patients on immunosuppressive therapy are less likely to respond. This study was aimed at investigating the efficacy of a Covid-19 vaccine (Pfizer-BioNTech) in patients with non-Hodgkin lymphoma treated with anti-CD20 monoclonal antibodies. Only 1 of 28 lymphoma patients (3.6%) developed a seropositive response, compared with 100% (28/28) of the healthy volunteers. The low levels of CD19+ lymphocytes among the lymphoma patients suggest that anti-CD20 treatment prevents the seropositive response to the vaccine. An additional vaccination might be indicated in these patients once B cells are repopulated.