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Background: mRNA vaccines elicit a durable humoral response to SARS-CoV-2 in adults, whereas evidence in children is lacking. This study aimed to evaluate the early and long-term immunological response after the BNT162b2 vaccine in children with or without a previous SARS-CoV-2 infection. Method(s): In a multicenter, prospective, observational study we profiled the immune response to the BNT162b2 vaccine in children aged 5-11 years attending the Pediatric Departments at the University of Padua and Bambino Gesu Children's Hospital in Rome (Italy). Forty-four healthy children (HC), 20 immune compromised (IC), and 18 children who previously developed MIS-C (MIS-C) were included in the study. Blood samples were collected pre-, 1, and 6 months after a 2-doses vaccination schedule. Neutralizing antibodies (NAbs) and anti-S-RBD IgG titers were analyzed through Plaque Reduction Neutralization Test (PRNT) and chemiluminescent immune-enzymatic assay (CLIA), respectively. B and T cell phenotypes were analyzed by flow cytometry. Geometric mean titers (GMTs) and 95% confidence intervals and median and interquartile range (IQR) of variables were evaluated according to pre-existing confirmed COVID-19. Result(s): Eighty-two children were studied;60 with a molecular-documented previous COVID-19 (Group A) and 22 without previous infection defined as the absence of antigen-specific antibodies before the vaccination (Group B). Overall, in Group A we observed higher NAbs GMTs, anti-S-RBD titers, and T- and B-reg cells than in Group A, at both 1 and 6 mo after vaccination (table);Nabs against the parental virus resulted to be greater in Group A than in Group B by a factor of 18 and 11, at 1 and 6 mo after vaccination, respectively. Both Groups recorded a decrease in antibody titers of approximately 50-70% between 1 and 6 months. A significant difference for Omicron NAbs (p=0.02) and anti-S-RBD (p=0.07) titers decay was observed between Group A and B;in contrast, Parental NAbs titers appeared to have similar trends in the 2 groups (p=0.47). Comparable antibody titers at 1 and 6 mo. (p=0.37) were detected across the three categories of HC, IC, and MIS-C (table). Conclusion(s): mRNA vaccination triggers a higher humoral response in children with a previous history of COVID-19, regardless of the immune deficiency or previous MIS-C, at least up to 6 mo, providing insight into boosting preexisting immunity with mRNA vaccines.
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Introduction: SARS-CoV-2 immune-response is mediated by both humoral and cellular immunity. However, since Ab levels wane faster than SARS-CoV-2 specific T cells immunity, cellular immunity represents an important factor for COVID-19 immune defence. Determining immunoreactivity of SARS-CoV-2 specific T cells is of clinical relevance in transplant recipients or patients treated with immunomodulant therapy. SARS-CoV-2 specific T cells assays are currently based on ELISA, whilst rapid tests are pivotal for real-time patients' evaluation. In this study, a novel direct real-time PCR (dRT-PCR) targeting mRNA of CXCL10 for measuring SARS-CoV-2 specific T cells, was tested and evaluated. Method(s): A total of 104 healthcare workers, with two or three doses of homologous (Pfizer/BioNTech, n = 82) or heterologous (Pfizer/BioNTech and Vaxzevria or Moderna, n = 22) vaccinations were asked to collect a blood (Li-He) sample. Blood was stimulated overnight with SARS-CoV-2 spike peptides (S-peptide) or treated with non-stimulating substance. Stimulated/treated samples were diluted in Buffer A, mixed with dqTACT MS then loaded into the cartridge. The analysis was performed using SCV2 T Activation kit, bCube and bApp (Hyris srl, Lodi, Italy), equipped by an automatic result interpretation based on artificial intelligence. For a subgroup of 49 samples, IFN-y releases to SARS-CoV-2 spike peptides were tested by Quant-T-Cell SARS-CoV-2 and ELISA (Euroimmune, Lubeck, Germany). Result(s): Seventy-nine (75.9%) and 25 (24.1%) were females and males, respectively. Twenty-nine subjects were previously infected by SARS-CoV-2. Overall mean age (+/- SD) was 45.9+/-13.3 years. At qualitative analyses, 97 subjects (93.2%) resulted reactive to S-peptides, 3 (2.8%) were borderline and 4 were negative (3.8%). These negatives had their third vaccinal dose in December/November 2021. Previous infected individuals presented reactivity to S-peptides, with the exception of one subject with resulted reactive also in the untreated sample. Samples tested with both dRT-PCR and ELISA perfectly agreed (100%) with both methods. At quantitative analyses, between-assay correlation was 0.32 (p<0.001). Conclusion(s): Hyris dRT-PCR appeared accurate for determining presence or absence of immunoreactivity of SARS-CoV-2 specific T cell, especially when rapid analyses are required, such as for organ transplantation.
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Background: The Severe Acute Respiratory Syndrome Coronavirus 2 related (SARS-CoV-2) has rapidly spread originating into the fifth documented pandemic wave. Dried blood spot (DBS) provides an alternative method to the venous blood samples to determine Ab, presenting several advantages, including the practicability, especially in infants, and the possibility to test a higher number of samples in a limited time. The main goal of this study was to measure seroprevalence of anti-SARS-CoV-2 IgG Ab in newborns, using DBS collected from January 2020 to December 2021. Method(s): Anti-SARS-CoV-2 IgG levels were determined using DBS by Anti-SARS-CoV-2 QuantiVac IgG ELISA assay (Euroimmune, Lubeck, Germany). Result(s): Preliminary analyses included 515 DBS from newborns, 54% males and 46% females, collected 2-3 days after birth. Overall, mean IgG levels, although below the positive threshold (>= 35.2 kBAU/L), were significantly higher in 2021 (Feb/21 and Mar/21), with respect to 2020 (Feb/20: 8.6+/-3.5, n=99 vs Feb/21: 28.1+/-42.8, n=40;Mar/20: 11.6+/-5.1, n=94 -Mar/21: 16.8+/-11.6, n=39, mean kBAU/L +/- DS, p<0.005). Moreover, an increased number of positive samples were found in 2021 (4/44 Gen/21;8/40 Feb/21;2/39 Mar/21). As expected, a trend of increase around 5% in DBS tested positive for anti-SARSCoV-2 IgG were found in December 2021, where IgG were above the positive threshold in 41.54% of DBS (450.926+/-873.291, mean kBAU/L +/- DS, n=65). Conclusion(s): In these preliminary data, newborn DBS seems to reflect population-wide infection rates during the studied periods. This suggests a potential role for DBS in COVID-19 surveillance, especially in infants and in areas where viral testing is limited.
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Globally, the reforms of healthcare systems aim to bring back the patient at the centre of these organisations after the issues related to the COVID-19 outbreak. The patient returns to be fully considered, as an individual whose must be protected physical and psychological health as well as social well-being. Humanization of care is returning to the foreground. For centuries, art has been used throughout Europe in the health context for its power to support patients in their disease. Today, this approach can be rediscovered in historical hospitals, where tradition, art and assistance coexist. This study aims to investigate the interest for the development of projects for the humanization of care exploiting the artistic heritage of the historical hospitals owned by Health Authorities. The cross-case analysis was chosen as study design. The case studies are the historical hospitals in the city centre of Venice, Florence, and Rome. The evaluation of the proposal was carried out through semi-structured interviews with the general managers of the Health Authorities, the medical directors of the selected hospitals and the delegates for the protection and promotion of cultural heritage. The results were analysed using a qualitative model (coding). All respondents welcomed the proposal to launch projects for the humanization of care that foresee the use of the artistic heritage of the historical hospitals to involve patients in the field of health care. Interviewees expressed the desire to invest human and structural resources in the development of these projects. Moreover, directors suggest choosing a specific target with which to start the experimentation and to dispense a specific training to future engaged social and health personnel. The implementation of projects for the humanization of care using the artistic heritage of historical hospitals can be replicated worldwide where healthcare institutions have a cultural wealth to be handed down, shared and valued. Key messages • In the post COVID-19 era, it is strategic to exploit artistic heritage owned by the Health Authority for the positive impact in the patient’s experience. • Artistic heritage claims its role as a health service for supporting patients, caregivers and also health workforce.
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Background In order to support primary care during the first pandemic wave (March 2020), the Italian Government instituted multiprofessional health teams called “USCA” (Special Continuity Care Units), which ensured continuity of care for COVID-19 patients who do not need hospitalization. The aim of our study was to compare the volumes of USCA service utilization in Florence (Tuscany, Italy) during the peak of home visits of three pandemic waves. Methods This single-center study followed a retrospective cross-sectional design. The USCA of the Heath District of Florence served a population of 366,190 people. The following data were collected: home medical visits, nursing home (NH) visits, visits in health-care hotels. The peak periods of three epidemic waves were considered in the analyses: the second wave (23 October - 20 November 2020), the third wave (25 March - 22 April 2021), and the Omicron period (27 December 2021 - 6 February 2022). The maximum 7-day moving averages of the daily number of visits during the three periods were calculated. Relative percent differences for visits comparing the considered periods were computed. Results Home visits during the third pandemic wave increased by 14% compared to the second wave (second wave: N = 1370, third wave: N = 1562), while a decrease was observed during the Omicron period (Omicron vs third wave: -21%;peak value: 41 vs 60). Visits in health-care hotels during the third wave doubled compared to the second wave. After the start of the COVID-19 vaccination campaign, NH visits steeply declined (third wave vs second wave: -95%;N = 323 vs 15;peak value= 14 vs 2 visits per day). During the Omicron period, NH visits increased by almost four times compared to the third wave period. Conclusions The USCA service utilization was significant in all the analyzed periods. In a pandemic context, it is necessary to strengthen primary care services such as USCA, which have proved to respond to rapidly changing health needs. Key messages • The USCA service is an innovative model of integrated home care that has proved to respond to rapidly changing health needs during all phases of the COVID-19 pandemic. • The USCA service utilization was significant during all phases of the pandemic. The USCA service has introduced new ways of working and new relationships between services in primary care.
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Multisystem inflammatory syndrome (MIS) post-SARS-COV-2 infection has been described in children. Few case reports of MIS in adults are available, the majority described in young previously healthy persons. Here we report the case of MIS that meets the Center for Disease Control definition of MIS in adults in an elderly patient with known type 2 diabetes with a recent history of COVID-19. As the number of COVID-19 cases continues to rise, we believe that more and more cases of adult MIS will be reported. Thus, investigations aiming to characterize the full spectrum of clinical manifestations, to clarify the pathogenetic mechanisms leading to adult MIS as well as long-term consequences are needed.
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Background: Understanding the long-term kinetics of the immune response against SARS-CoV-2 infection is crucial in guiding public health policies and optimizing of vaccination strategies. While it is known that SARS-CoV-2 specific antibodies may persist in adults 12 months after infection, data are lacking in the pediatric population. We herein describe the long-term immune response in children following SARS-CoV-2 infection. Methods: Single-centre, prospective observational study analyzing family clusters of COVID-19 attending the Pediatric Department, University of Padua (Italy). Confirmed COVID-19 infection was defined by positive SARS-CoV-2 PCR and/or IgG serology. All patients with confirmed infection at enrolment underwent serological follow-up at 1-4, 5-10, and >10 months after infection. Plasma was analyzed to quantify anti-SARS-CoV-2 S-RBD IgG, by chemiluminescent immunoassay, performed on MAGLUMI™2000 Plus (Snibe Diagnostics). IgG title >4.3 kBAU/L was considered positive. Results: Among 902 subjects (252 COVID-19 family clusters), 698 had confirmed COVID-19, including 352 children/older siblings aged 8.6 ±5.1 years, and 346 parents aged 42.5 ±7.1 years;of those, 96.5% cases had asymptomatic/mild COVID-19. Children showed significantly higher S-RBD IgG titers than older subjects across all follow-up time points, with an overall mean S-RBD IgG titer <3 years of age five-fold higher than adults (282.3 [139-516.6] kBAU/L vs 56.7 [24.6-136.9] kBAU/L, p<0.001) (Table). The longitudinal analysis of 60 subjects sampled at least twice during follow-up demonstrated the persistence of antibodies up to 10 months from infection in all age classes. Subjects >6 years of age showed a significant progressive decline of the S-RBD IgG titer from the first serological follow-up. While, in younger children antibodies remained stable at 5-10 months of follow-up (p=0.0625), with a subsequent significant decline afterwards (p<0.001). Conclusion: In our unique family cluster cohort, we confirmed the different kinetics of the COVID-19 humoral response across several age groups of asymptomatic/mild COVID-19 cases in our family-cluster cohort. Children presented with higher S-RBD IgG titer at every time point up to 10 months of follow-up. Children less than 3 years demonstrated a more intense long-term resilience of their immune response, which started to decline significantly only after ten months from infection.
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Background and Aim: Salivary SARS-CoV-2 Ab determination could be suitable for monitoring the viral spread and vaccination efficacy, especially in pediatric patients. We investigated N/S1-RBD IgG antibody levels in salivary samples of infectious-naïve vaccinated subjects and of COVID-19 patients, further comparing levels with serum anti-SARS-CoV-2 S-RBD IgG. Methods: A total of 72 subjects were enrolled at the Padova University Hospital: 36 COVID-19 patients and 36 health care workers (HCW), who underwent a complete vaccination campaign with BNT162b2 (BioNTech/Pfizer). All collected a salivary sample, using Salivette (Sarstedt, Nümbrecht Germany). For 9 HCW, salivary samples were collected at three different times within the same day (before breakfast, at 10 am, and after lunch). A serum sample was also collected for all individuals. Time post symptoms onset or time from the first vaccine were also recorded. Salivary COVID-19 N/S1 RBD (sal-IgG) ELISA (RayBiotech, GA, USA) and anti-SARS-CoV-2 S-RBD IgG Ab (ser-IgG) (Snibe Diagnostics, Shenzhen, China) were used for determining IgG Ab. Results: Subjects' mean age (±sd) was 35.8±18.2 yrs. Age significantly differed (p<0.001) from COVID-19 patients [29.7±17.3 yrs] and HCW [47.1±12.9 yrs]. Positive sal-IgG were found in 70/72 (97.2%) samples;in sera, 71/72 (98.6%) samples were positive to ser-IgG. The sal-IgG median levels differed from COVID-19 to vaccinated HCW, being in salivary samples 0.21 kAU/L and 0.8 kAU/L (p =0.030), respectively;median levels for ser-IgG in COVID-19 and vaccinated HCW were 135 kBAU/L and 940 kBAU/L, respectively (p<0.001). Salivary IgG levels were not influenced by time post-symptom onset or time post-vaccination, both on vaccinated HCW (rho= -0.147, p=0.402) and COVID-19 subjects (rho=0.0267, p=0.986). Ser-IgG levels was not influenced by the time post-symptom onset for COVID-19 subjects (rho=0.102, p=0.419), while a strong significant correlation was found with time post-vaccination in HCW (rho=-0.6292, p<0.001). Sal-IgG levels were notinfluenced by the daytime of collection (rho=0.148, p=0.373). Passing-Bablok regressions showed that sar- IgG and ser-IgG comparability was assessable only when ser-IgG values were divided by 1000, being slope and intercept 0.068 (95%CI: 0.069-0.341) and 0.221 (95%CI:- 0.097 to 0.786), respectively. Conclusions: Salivary IgG is efficiently detectable both in COVID-19 and in vaccinated individuals and analyses appeared to be not influenced by the daytime of collection. The analyses performed showed that, overall, sal-IgG were lower than ser-IgG, and thus comparability with serum levels needs to be better explored.
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Background: Serology could help defining the real extent of Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV2) diffusion in the population, especially in individuals considered at higher risk of SARS-CoV2 infection (COVID-19), such as Spondiloarthritis (SpA) patients undergoing immunosuppressive therapy or health care workers (HCW). In fact, COVID-19 detection is complicated by the fact that many patients can be asymptomatic. In these cases, it has also been suggested that a weaker immune response might be elicited. In this context, the role of anti-cytokine targeted therapy -commonly used as treatment in SpA-is uncertain, as it is not clear whether it is detrimental or protective towards severe disease forms. Objectives: The aim of the study was to explore the potential role of serology in detecting previous contact with SARS-CoV2 in SpA patients and HCW, and compare the frequency of positive findings with a control population. Methods: Consecutive patients affected by axial or peripheral SpA, classified according to Assessment of SpondyloArthritis international Society (ASAS) criteria and undergoing cytokine-targeted therapy, as well as HCW and controls from the pre-COVID-19 era (control group, 2015) were recruited. In SpA patients, disease activity was assessed by Ankylosing Spondylitis Disease Activity Score (ASDAS) and Disease Activity Score on 28-joint-count (DAS28). Sera from all patients were analysed through chemiluminescent analytical system (CLIA) for the presence of IgG and IgM anti-SARS-CoV2. Patients with a positive serological test (either IgM or IgG) additionally underwent real time Polymerase Chain Reaction (RT-PCR) in nasopharyngeal swabs in order to test for active infection. In SpA patients, serology was repeated after 3 months. Data across the 3 groups were compared by ANOVA or Chi-square, while comparison between 2 groups were conducted by Wilcoxon signed rank test or Chi-Square, for continuous and categorical data respectively. P ≤ 0.05 were considered as significant. Results: A total of 396 patients were recruited: 200 SpA, 95 HCW and 101 healthy controls. SpA patients were mostly (54%) males, with mean age 49.6 ±14.7 years, and all were treated with anti-TNFα (78%), anti-IL-17 (9%) and anti-IL-23 drugs (7%), or small molecules (6%). Their disease activity level was moderate-low as assessed by ASDAS (1.95 ±0.98) and DAS28 (2.33 ±2.02). Among HCW and controls, 35% and 62% were male, with mean age 46.7 ±12.9 and 50.6±10.6 respectively. Positive serology (IgM or IgG, or both) was found in 12.5% SpA patients, 8.4% HCW, 0% controls (p=0.001). Among these, IgM titres were higher in the SpA group than in HCW (2.76±2.94 versus 0.80±0.67 KU/L, p= 0.016), while IgG mean titres were lower in the SpA group than in HCW (0.88±3.18 KU/L versus 1.05±0.88, p= 0.035). SpA patients with positive serology more frequently reported COVID-19 like symptoms than those with negative serology (20% vs 4%, p=0.009) and 2 had COVID-19 as confirmed by RT-PCR, none with a severe disease course. None of the HCW reported symptoms or tested positive by RT-PCR. In the SpA patients, at 3 months, the mean IgM titre decreased from 2.76±2.93 to 2.38±2.95 (p=0.001), while the IgG titres decreased from 0.89±3.25 to 0.31±0.87 (p=ns). Interestingly, the IgM or IgG titer at a single-patient level did not seem to change much in terms of absolute value (Figure 1), except in one patient, with documented COVID-19 (positive RT-PCR), in whom IgG level even decreased at 3 months. Conclusion: Serology revealed that exposure to COVID-19 in SpA patients, as well as HCW, was higher than expected based on reported symptoms. Targeted anti-cytokine therapy could act as a protective factor for a severe disease course in SpA patients. However, in this population, IgG and IgM titres did not change in a clinically significant manner at 3 months, and patient did not seem to develop an immune profile consistent with durable response. This result could be due to a weaker immune response in mild infections, but further studies are w rranted to clarify the pathophysiology beyond these observations.
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Background: Recent evidences suggest that SARS-CoV-2 neutralizing antibodies (Nabs) may persist over time, however lack of knowledge still regards the pediatric population. Methods: A single-centre, prospective observational study evaluated family clusters of COVID-19 attending the Pediatric Department, University Hospital of Padua (Italy). Confirmed COVID-19 was defined by positive SARS-CoV-2 molecular detection and/or serology;patients/family symptom's and virological positivity were considered to define the infection onset (baseline). Blood samples were analyzed in pair to detect Nabs through Plaque Reduction Neutralization Test (PRNT), and IgG through chemiluminescent immuneenzymatic assay (CLIA) MAGLUMI™ 2000 Plus;IgG >1.1 kAU/L and/or PRNT≥1:10 were considered positive. SARS-CoV-2 viral load (VL) was quantified by multiplex quantitative assay based on One-Step RT-ddPCR. Geometric mean titers (GMT) and 95% Confidence Intervals of IgG/PRNT were evaluated, stratified by age and time from baseline to sample collection. Trends over time of immune-virological response were assessed. P-value <0.05 was considered statistically significant. Results: Among 213 subjects (57 families) evaluated, 155 had confirmed COVID-19 including 73 (47%) children/older siblings of 8 years median age (IQR 4-13) and 82 (53%) parents aged 42 years (IQR 34-46);93.5% had asymptomatic/mild COVID-19. From the cumulative analysis of 194 blood samples, Nabs persisted over a median period of 95 days (IQR, 67-133) from baseline. Children showed significantly higher NAbs than older subjects, with children <3 years ranging from a 4-fold difference at 1-2 months to 8.8-fold difference at 3-6 months after baseline, compared to adults (table). The longitudinal assessment of 42 subjects sampled at 60 days (SD+/-9.9) and at 150 days (SD+/-24.2) showed a 2-fold increase in NAbs in children <6 years (PRNT 144, 95% C.I. 74.42-277.94 versus 303, 95% C.I. 196.43-468.57) and a substantial stability in Nabs among older subjects. CLIA IgG significantly decreased over time for all age classes, becoming negative in 13/42 subjects (31%), compared to 1/42 subjects detected by PRNT. Among 32 individuals checked for VL within 4 days from baseline, VL directly correlated with PRNT titers in subjects >15 years (Pearson Coefficient =0.70, p=0,0349) but not in pediatric cases. Conclusion: Asymptomatic/mild COVID-19 disease triggers in children a superior and persistent humoral response compared to adults.