Diminished and waning immunity to COVID-19 vaccination among hemodialysis patients in Israel: the case for a third vaccine dose

18-month longitudinal SARS COV-2 neutralizing antibody dynamics in haemodialysis patients receiving heterologous 3-dose vaccination (AZD-1222- AZD-1222- BNT162b2) in a lower middle income setting

BACKGROUND

Patients with chronic kidney disease on haemodialysis (HD) were given priority COVID-19 vaccination due to increased disease risk. The immune response to COVID-19 vaccination in patients on HD was diminished compared to healthy individuals in 2-dose studies. This study aimed to evaluate seroconversion rate, neutralizing antibody (nAB) levels and longitudinal antibody dynamics to 3-dose heterologous vaccination against COVID-19 in a cohort of HD patients compared to healthy controls and assess patient factors associated with antibody levels.

METHODS

This study was a case-control longitudinal evaluation of nAB dynamics in 74 HD patients compared to 37 healthy controls in a low/middle income setting. Corresponding samples were obtained from the two cohorts at time-points (TP) 1-1-month post 2nd dose of AZD1222 vaccine, TP2- 4 months post 2nd dose, TP4- 2 weeks post 3rd dose with BNT162b2 vaccine, TP5-5 months post 3rd dose and TP6-12 months post 3rd dose. Additional data is available at TP0- pre 2nd dose and TP3- 6 months post 2nd dose in HC and HD cohorts respectively. Anti-SARS-CoV-2 nAB were detected using Genscript cPassTM pseudoviral neutralization kit. Demographic and clinical details were obtained using an interviewer administered questionnaire.

RESULTS

Cohorts were gender matched while mean age of the HD cohort was 54.1yrs (vs HCs mean age, 42.6yrs, p < 0.05). Percentage seroconverted and mean/median antibody level (MAB) in the HD cohort vs HCs at each sampling point were, TP1-83.7% vs 100% (p < 0.05), MAB-450 IU/ml vs 1940 IU/ml (p < 0.0001); TP2-71.4% vs 100%, (p < 0.001), MAB- 235 IU/ml vs 453 IU/ml, (p < 0.05); TP4-95.2% vs 100% (p > 0.05), MAB-1029 IU/ml vs 1538 IU/ml (p < 0.0001); TP5-100% vs 100%, MAB-1542 IU/ml vs 1741IU/ml (p > 0.05); TP6-100% vs 100%, MAB-1961 IU/ml vs 2911 IU/ml (p > 0.05). At TP2, patients aged < 60 years (p < 0.001) were associated with maintaining seropositivity compared to patients > 60 years.

CONCLUSION

Two dose vaccination of haemodialysis patients provided poor nAB levels which improved markedly following 3rd dose vaccination, the effect of which was long- lasting with high nAB levels in both patients and controls detectable at 1 year follow-up.

Low antibody levels associated with significantly increased rate of SARS-CoV-2 infection in a highly vaccinated population from the US National Basketball Association

SARS-CoV-2 antibody levels may serve as a correlate for immunity and could inform optimal booster timing. The relationship between antibody levels and protection from infection was evaluated in vaccinated individuals from the US National Basketball Association who had antibody levels measured at a single time point from September 12, 2021, to December 31, 2021. Cox proportional hazards models were used to estimate the risk of infection within 90 days of serologic testing by antibody level (<250, 250-800, and >800 AU/mL1 ), adjusting for age, time since last vaccine dose, and history of SARS-CoV-2 infection. Individuals were censored on date of booster receipt. The analytic cohort comprised 2323 individuals and was 78.2% male, 68.1% aged ≤40 years, and 56.4% vaccinated (primary series) with the Pfizer-BioNTech mRNA vaccine. Among the 2248 (96.8%) individuals not yet boosted at antibody testing, 77% completed their primary vaccine series 4-6 months before testing and the median (interquartile range) antibody level was 293.5 (interquartile range: 121.0-740.5) AU/mL. Those with levels <250 AU/mL (adj hazard ratio [HR]: 2.4; 95% confidence interval [CI]: 1.5-3.7) and 250-800 AU/mL (adj HR: 1.5; 95% CI: 0.98-2.4) had greater infection risk compared to those with levels >800 AU/mL. Antibody levels could inform individual COVID-19 risk and booster scheduling.

Tixagevimab and Cilgavimab (Evusheld) Boosts Antibody Levels to SARS-CoV-2 in End-Stage Renal Disease Patients on Chronic Hemodialysis: A Single-Center Study

Background and Objectives: In addition to a suboptimal and rapidly diminishing response to the coronavirus disease 2019 (COVID-19) vaccine, hemodialysis (HD) patients are at risk for developing a severe COVID-19 infection. In 2022, the combination of cilgavimab and tixagevimab (Evusheld, AstraZeneca) was approved for COVID-19 preexposure prophylaxis in high-risk groups. The purpose of this study was to evaluate the humoral response and short-term safety of this antibody combination in a group of HD patients. Materials and Methods: Seventy-three adult maintenance hemodialysis patients were recruited from a tertiary-care hospital for this double-blinded, non-randomized, placebo-controlled study. Patients were placed into two groups: the intervention group (n = 43) received a single 300 mg dosage of cilgavimab and tixagevimab, while the control group (n = 30) received a saline placebo. The titer of COVID-19-neutralizing antibodies was measured at baseline and after 1 and 6 months. The patients were evaluated for any drug-related adverse effects and monitored for six months for the emergence of any COVID-19-related events. Results: Patients in the intervention group were substantially older and had been on HD for longer (p = 0.002 and 0.006, respectively). The baseline antibody levels were higher in the Evusheld group. The antibody level in the intervention group increased significantly after 1 month and remained consistent for 6 months, whereas the antibody level in the control group fell significantly after 6 months during the study period (Wald χ2 = 30.620, p < 0.001). The drug-related adverse effects were modest and well-tolerated, and only seven patients experienced them. Six months after study enrollment, 10 patients in the intervention group and 6 patients in the control group had been infected with COVID-19, respectively. In the control group, ICU admission and mortality were observed, but in the intervention group, the infection was milder with no aggressive consequences. Conclusions: This study demonstrated the short-term safety and efficacy of tixagevimab-cilgavimab for COVID-19 preexposure prophylaxis in HD patients. These findings require more studies with more HD patients and longer follow-up periods.

IgG level of the third booster dose for mRNA of SARS-CoV-2 vaccines among Iraqi healthcare workers

Mass vaccination is an effective method for controlling the outbreak of coronavirus disease 2019 (COVID-19) and limiting the consequent mortality due to severe COVID-19. After the second dose, immunity can decline in certain cases over time; therefore, a third booster dose should be administered. Therefore, the present study aimed to assess the immunogenicity of the third dose of the messenger ribonucleic acid BioNTech COVID-19 vaccine and determine the effect of the third booster dose of messenger ribonucleic acid COVID-19 vaccines, specifically (Oxford/AstraZeneca COVID-19 vaccine/AZD1222), BioNTech COVID-19 vaccine, and Sinopharm among healthcare workers. This longitudinal panel design was conducted with 256 healthcare workers in Duhok Province, Iraq, from June to October 2022. Most participants had a normal body mass index (44% and 41% in the first and second phase, respectively). In the first phase, significant associations were observed between COVID-19 vaccines and positivity (P value ≤ .001), and between age groups and positivity (P value = .001). The mean severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) anti-spike receptor-binding domain immunoglobulin G antibody level in the ninth month was the highest among those who had received the Pfizer vaccine (6.7930), followed by AstraZeneca (2.8492), and Sinopharm (0.3060). In the 12th month, all 82 participants received Pfizer as a booster dose, and the highest mean SARS-CoV-2 anti-spike receptor-binding domain immunoglobulin G antibody in the 12th month belonged to those whose second dose was Pfizer (46.8835), followed by AstraZeneca (36.4635), and Sinopharm (21.7815). The Pfizer vaccine is highly effective in restoring SARS-CoV-2-specific immune responses and is well-tolerated. However, further investigation is required to determine the duration of disease protection of the third dose of the COVID-19 vaccine.

A perturbative approach to the analysis of many-compartment models characterized by the presence of waning immunity

The waning of immunity after recovery or vaccination is a major factor accounting for the severity and prolonged duration of an array of epidemics, ranging from COVID-19 to diphtheria and pertussis. To study the effectiveness of different immunity level-based vaccination schemes in mitigating the impact of waning immunity, we construct epidemiological models that mimic the latter's effect. The total susceptible population is divided into an arbitrarily large number of discrete compartments with varying levels of disease immunity. We then vaccinate various compartments within this framework, comparing the value of [Formula: see text] and the equilibria locations for our systems to determine an optimal immunization scheme under natural constraints. Relying on perturbative analysis, we establish a number of results concerning the location, existence, and uniqueness of the system's endemic equilibria, as well as results on disease-free equilibria. We use numerical techniques to supplement our analytical ones, applying our model to waning immunity dynamics in pertussis, among other diseases. Our analytical results are applicable to a wide range of systems composed of arbitrarily many ODEs.

Egyptian hemodialysis patients' willingness to receive the COVID-19 vaccine booster dose: a multicenter survey

BACKGROUND

Health authorities have struggled to increase vaccination uptake since the COVID-19 vaccines became available. However, there have been increasing concerns about declining immunity after the initial COVID-19 vaccination with the emergence of new variants. Booster doses were implemented as a complementary policy to increase protection against COVID-19. Egyptian hemodialysis (HD) patients have shown a high rate of hesitancy to COVID-19 primary vaccination, yet their willingness to receive booster doses is unknown. This study aimed to assess COVID-19 vaccine booster hesitancy and its associated factors in Egyptian HD patients.

METHODS

A face-to-face interview was conducted with closed-ended questionnaires distributed to healthcare workers in seven Egyptian HD centers, mainly located in three Egyptian governorates, between the 7th of  March and the 7th of April 2022.

RESULTS

Among 691 chronic HD patients, 49.3% (n = 341) were willing to take the booster dose. The main reason for booster hesitancy was the opinion that a booster dose is unnecessary (n = 83, 44.9%). Booster vaccine hesitancy was associated with female gender, younger age, being single, Alexandria and urban residency, the use of a tunneled dialysis catheter, not being fully vaccinated against COVID-19. Odds of booster hesitancy were higher among participants who did not receive full COVID-19 vaccination and among those who were not planning to take the influenza vaccine (10.8 and 4.2, respectively).

CONCLUSION

COVID-19 booster-dose hesitancy among HD patients in Egypt represents a major concern, is associated with vaccine hesitancy with respect to other vaccines and emphasizes the need to develop effective strategies to increase vaccine uptake.

The safety and immunogenicity of inactivated COVID-19 vaccine in old pulmonary tuberculosis patients

The immunogenicity and safety of vaccines against coronavirus disease 2019 (COVID-19) remain unknown in patients with a history of pulmonary tuberculosis (OPTB). Therefore, the safety and effectiveness of inactivated vaccines against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) were assessed in patients with a history of PTB. The study cohort included 106 healthy controls and 93 adult patients with OPTB who received a two-dose vaccination. The study period was 21 to 105 days. Concentrations of antibodies (Abs) against receptor-binding domain (RBD) IgG and SARS-CoV-2 neutralizing Abs (NAbs) were measured, in addition to the frequencies of SARS-CoV-2-specific B and a portion T cells. The incidence of adverse events was similar between the OPTB patients and healthy controls. No severe adverse events occurred. Concentrations of Abs against RBD-IgG and CoV-2 neutralizing Abs in addition to the frequencies of RBD-specific memory B cells proportions were lower in OPTB patients than the healthy controls (all, p < 0.05), while the frequencies of cytotoxic T-lymphocyte-associated protein 4 (CTLA-4⁺) cells were higher (p = 0.023). There was no obvious correlation between age and blood concentrations of Abs against RBD-IgG and CoV-2 neutralizing Abs, while immune responses were similar in the fibrosis and calcification groups. The period of time following full-course vaccination and lymphocyte counts were associated to anti-RBD-IgG responses. Inactivated COVID-19 vaccinations were well tolerated in OPTB patients, although immunogenicity was limited in this population. This study has been registered at ClinicalTrials.gov (NCT05043246).

The challenges of the pandemic and the vaccination against covid-19 in pediatric patients with kidney disease

The covid-19 vaccine confers direct protection and reduces transmission rates of the virus and new variants. Vaccines from Pfizer/BioNTech and CoronaVac have been cleared for children in Brazil. They are safe, effective, and immunogenic. There are no known complications associated with the use of steroids or vaccines in pediatric patients with covid-19 and nephrotic syndrome. With or without immunosuppression, these patients are not at increased risk of severe covid-19, and steroids are safe for them. A milder form of covid-19 occurs in patients with chronic kidney disease without the need for hospitalization. The vaccine response may be reduced and/or the duration of antibodies after vaccination may be shorter than in the general population. However, considering risk of exposure, vaccination against covid-19 is recommended. It is believed that patients with hemolytic-uremic syndrome are at higher risk of severe covid-19. Vaccination is recommended, although specific data on the safety and efficacy of the covid-19 vaccine are limited. There is agreement that the benefits of induced immunity outweigh the risks of immunization. Vaccination against covid-19 is recommended for children and adolescents needing kidney transplantation or who have undergone transplantation. These patients present decreased immune response after vaccination, but immunization is recommended because the benefits outweigh the risks of vaccination. Current recommendations in Brazil stipulate the use of the messenger RNA vaccine. This paper aims to provide pediatric nephrologists with the latest knowledge about vaccination against covid-19 for children with kidney disease.

Blunted humoral immune response to the fourth dose of BNT162b2 COVID-19 vaccine in patients undergoing hemodialysis

BACKGROUND

We aimed to investigate the impact of a fourth dose of BNT162b2 vaccine (Comirnaty®, Pfizer-BioNTech) on anti-SARS-CoV-2 (anti-S IgG) antibody titers in patients receiving hemodialysis (HD) and healthcare workers (HCWs).

METHODS

A multi-institutional retrospective study at five dialysis clinics in Japan was conducted using 238 HD patients and 58 HCW controls who received four doses of the BNT162b2 mRNA vaccine. Anti-S IgG titers were measured at 1, 3, and 6 months after the second dose, at 1 and 5/6 months after the third dose, and at 1 month after the fourth dose of vaccine.

RESULTS

The log anti-S IgG titers of the HD patients after the second vaccination were significantly lower than those of the control group, but equalized 1 month after the third vaccination: 9.94 (95% CI 9.82-10.10) vs. 9.81 (95% CI 9.66-9.96), (P = 0.32). In both groups, the fold-increase in anti-S IgG titers was significantly lower after the fourth dose than after the third dose of vaccine. In addition, there was a strong negative correlation between antibody titers 1 month after the fourth vaccination and antibody titers immediately before the vaccination. In both groups, the waning rate of anti-S IgG titers from the post-vaccination peak level after the third vaccine dose was significantly slower than that after the second dose.

CONCLUSIONS

These findings suggest that the humoral immune response was blunted after the fourth dose of the conventional BNT162b2 vaccine. However, multiple vaccinations could extend the window of humoral immune protection.

COVID-19 in Elderly Patients Receiving Haemodialysis: A Current Review

There is an increased incidence of elderly adults diagnosed with kidney failure as our global aging population continues to expand. Hence, the number of elderly adults indicated for kidney replacement therapy is also increasing simultaneously. Haemodialysis initiation is more commonly observed in comparison to kidney transplantation and peritoneal dialysis for the elderly. The onset of the coronavirus 2019 (COVID-19) pandemic brought new paradigms and insights for the care of this patient population. Elderly patients receiving haemodialysis have been identified as high-risk groups for poor COVID-19 outcomes. Age, immunosenescence, impaired response to COVID-19 vaccination, increased exposure to sources of COVID-19 infection and thrombotic risks during dialysis are key factors which demonstrated significant associations with COVID-19 incidence, severity and mortality for this patient group. Recent findings suggest that preventative measures such as regular screening and, if needed, isolation in COVID-19-positive cases, alongside the fulfillment of COVID-19 vaccination programs is an integral strategy to reduce the number of COVID-19 cases and consequential complications from COVID-19, particularly for high-risk groups such as elderly haemodialysis patients. The COVID-19 pandemic brought about the rapid development and repurposing of a number of medications to treat patients in the viral and inflammatory stages of their disease. However, elderly haemodialysis patients were grossly unrepresented in many of these trials. We review the evidence for contemporary treatments for COVID-19 in this population to provide clinicians with an up-to-date guide. We hope our article increases awareness on the associations and impact of COVID-19 for the elderly haemodialysis population, and encourage research efforts to address knowledge gaps in this topical area.

Severity of COVID-19 among Residents in Aged Care Facilities in Victoria, Australia: A Retrospective Cohort Study Comparing the Delta and Omicron Epidemic Periods

OBJECTIVES

During the COVID-19 pandemic, no country with widespread community transmission has avoided outbreaks or deaths in residential aged care facilities (RACFs). As RACF residents are at high risk of morbidity and mortality from COVID-19, understanding disease severity risk factors is imperative.

DESIGN

This retrospective cohort study aimed to compare COVID-19 disease severity (hospitalization and deaths) and associated risk factors among RACF residents in Victoria, Australia, across Delta and Omicron epidemic periods.

SETTINGS AND PARTICIPANTS

Resident case hospitalization risk (HR) and case fatality risk (CFR) were assessed using Victorian RACFs COVID-19 outbreaks data across 2 epidemic periods; Delta, 994 resident cases linked to 86 outbreaks; and Omicron, 1882 resident cases linked to 209 outbreaks.

METHODS

Adjusting for outbreak-level clustering, age, sex, up-to-date vaccination status, and time since last vaccination, the odds of hospitalization and death were compared using mixed effects logistic regression.

RESULTS

The HR and CFR was lower during the Omicron period compared with the Delta period [HR 8.2% vs 24.6%, odds ratio (OR) 0.17, 95% CI 0.11-0.26, and CFR: 11.4% vs 18.7%, OR 0.40, 95% CI 0.28-0.56]. During both periods, males had higher odds of hospitalization and odds of death; being up to date with vaccination reduced odds of hospitalization by 40% (excluding nonemergency patient transfers) and odds of death by 43%; and for each month since last vaccination, odds of hospitalization increased by 9% and odds of death by 16%.

CONCLUSIONS AND IMPLICATIONS

This study provides empirical evidence of lower COVID-19 severity among RACF residents in the Omicron period and highlights the importance of up-to-date and timely vaccination to reduce disease severity in this cohort.

COVID-19 vaccine and booster hesitation around the world: A literature review

The development of COVID-19 vaccines has helped limit the extent of the pandemic, which over the past 2 years has claimed the lived of millions of people. The Moderna and Pfizer COVID-19 vaccines were the first to be manufactured using mRNA technology. Since then, other manufacturers have built their own vaccines which utilize adenovirus vector, whole inactivated coronavirus, and protein subunit methods. Given the continued mutation of the SARS-CoV-2 virus, a booster of the COVID-19 vaccine offers additional protection for citizens, especially those with comorbid conditions. However, uptake of the vaccine and booster has faced hurdles. This literature review aims to analyze the acceptance of the COVID-19 booster among different populations throughout the world. Keywords searched include "COVID-19 vaccine rates OR COVID-19 booster rates," "COVID-19 vaccine hesitancy," "COVID-19 booster hesitancy," "reasons against COVID-19 vaccine," "reasons for COVID-19 vaccine," and "COVID-19 vaccine acceptance" (for each country). Research articles indexed in PubMed, University of Illinois Urbana-Champaign Library, and Google Scholar were included. Despite the proven effectiveness of the COVID-19 booster, vaccine hesitancy is still causing suboptimal compliance to the primary vaccine and booster, thus slowing down control of the pandemic. Reasons for vaccine hesitancy differ by country and acceptance is affected by misinformation, political circumstances, and cultural values. Among the most common reasons found are distrust in the government, a lack of safety information, and fear of side effects. Uptake of the COVID-19 vaccine has also been delayed in low and middle income countries due to resource allocation and as a result, these countries have fallen behind vaccination benchmarks. The future of COVID-19 vaccination is unknown, but vaccine mandates and additional booster doses are a possibility. Determining the ethical impact that these policies could have will allow for the best implementation.

Anti-SARS-CoV-2 spike IgG following injection of the third dose vaccine: A systematic review with meta-analysis of heterologous versus homologous vaccination

Background

The mass vaccination is a key strategy to prevent and control the coronavirus disease 2019 (COVID-19) pandemic. Today, several different types of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been developed worldwide. These vaccines are usually administered in a two-dose schedule, and the third dose is currently being administered in most countries. This study aimed to systematically review and meta-analyze the immunogenicity of heterologous vs. homologous vaccination after administration of the third dose of COVID-19 vaccines.

Methods

Electronic databases and websites including Scopus, PubMed, Web of Science, and Google scholar were searched for relevant randomized clinical trial (RCT) studies. After applying the inclusion and exclusion criteria, a total of three RCTs were included in the study. These RCTs were included 2,613 healthy adults (18 years or older and without a history of laboratory-confirmed COVID-19) with 15 heterologous and five homologous prime-boost vaccination regimens. Anti-SARS-CoV-2-spike IgG levels at day 28 after administration of the third dose, were compared between the heterologous and homologous regimens.

Results

The highest antibody responses had been reported for the homologous vaccination regimen of m1273/m1273/m1273 (Moderna), followed by the heterologous regimen of BNT/BNT/m1273. In addition, the immunogenicity of viral vector and inactivated vaccines was remarkably enhanced when they had been boosted by a heterologous vaccine, especially mRNA vaccines.

Conclusion

This systematic review suggests that mRNA vaccines in a homologous regimen induce strong antibody responses to SARS-CoV-2 compared to other vaccine platforms. In contrast, viral vector and inactivated vaccines show a satisfactory immunogenicity in a heterologous regimen, especially in combination with mRNA vaccines.

Humoral response to vaccination against SARS-CoV-2 in patients undergoing dialysis

Patients undergoing maintenance dialysis have a higher mortality rate associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and response rates to vaccination against SARS-CoV-2 vary from 29.6% to 96.4% in such patients. This study aimed to assess the immunogenicity of SARS-CoV-2 vaccination in Korean patients undergoing dialysis. We enrolled 70 SARS-CoV-2-vaccinated patients undergoing dialysis, with 11 healthcare workers serving as healthy control subjects. Thirty-two patients had received a third vaccination, whereas 38 had received 2 vaccinations. The healthy control subjects completed the second vaccination. Immunoglobulin G (IgG) antibodies targeting the receptor-binding domain of the S1 subunit of the SARS-CoV-2 spike protein were measured The vaccination responder rates were 86% (37/43), 96% (26/27), and 91% (10/11) in the patients undergoing hemodialysis and peritoneal dialysis and healthy controls, respectively. IgG antibody levels were significantly higher when a third dose was administered, independent of the type of vaccine or the time interval between vaccination and the subsequent blood sampling date. When a third dose of vaccine was administered, there was no difference in IgG antibody levels between those receiving cross-vaccination or a single vaccine. There was no significant difference in IgG antibodies between healthy controls and patients undergoing dialysis. Patients on dialysis exhibited a sufficient antibody-related response to vaccination against SARS-CoV-2, even in those receiving cross-vaccination, and the antibody titer was higher after a third vaccination. Therefore, it is necessary to administer a third vaccine dose to Korean patients undergoing dialysis.

A systematic review assessing the effectiveness of COVID-19 mRNA vaccines in chronic kidney disease (CKD) individuals

Background: SARS-CoV-2 is a coronavirus that has rapidly spread across the world with a detrimental effect on the global population. Several reports have highlighted an increased mortality rate and a higher severity of COVID-19 infection in chronic kidney disease (CKD) individuals. Upon the development of various SARS-CoV-2 vaccines, mRNA vaccines including BNT162b2 and mRNA-1273 were deemed safe, with a high efficacy in preventing COVID-19 in the general population. This review investigates whether  SARS-CoV-2 mRNA vaccines are as effective in triggering an immune response in Dialysis Patients (DPs) and Kidney Transplant Recipients (KTRs) and if a third dose is required in this  population. Methods: A systematic search employing the PRISMA criteria was conducted in several major databases, with the data being extracted from publications for the period January 2021 to May 2022 (PROSPERO: CRD42022338514, June 15, 2022). Results: 80 studies were included in this analysis with a total cohort number of 15,059 participants. Overall, 85.29% (OR = 17.08, 95% CI = 15.84-18.42, I ² = 98%) and 41.06% (OR = 0.52, 95% CI = 0.48-0.5, I ² = 95%) of DPs and KTRs included in this review showed positive seroconversion after two doses of either mRNA vaccine, respectively. A total 76% (OR = 6.53, 95% CI = 5.63-7.5, I ² = 96%) of the cohort given a third dose of an mRNA vaccine demonstrated positive seroconversion, with 61.86% (OR = 2.31, 95% CI = 1.95-2.75 I ² = 95%) of the cohort that was assessed for a cellular response displaying a positive response. Conclusions: This data emphasises a reduced incidence of a positive immune response in DPs and KTRs compared to healthy controls, albeit a better response in DPs than when compared to KTRs alone was observed. A third dose  appears to increase the occurrence of an immune response in the overall DP/KTR cohort.

Fatality rate, risk factors, and functional decline in peritoneal dialysis patients with coronavirus disease 2019: A nationwide cohort study

Background

The fatality rates and factors associated with death from coronavirus disease 2019 (COVID-19) in hemodialysis patients have been extensively investigated. However, data on peritoneal dialysis (PD) patients remain scarce.

Materials and methods

In this nationwide cohort study, we assessed the 28-day COVID-19-related fatality rate in PD patients between August 2021 and July 2022 using data from the InCov19-PD registry. Predictors associated with death were evaluated using a multivariable Cox regression model. Changes in functional status before and during COVID-19 were also examined.

Results

A total of 1,487 eligible participants were evaluated. During the study period, 196 participants died within 28 days after COVID-19 diagnosis (case fatality rate: 13%). In a multivariable Cox regression model, an increased risk of death within 28 days after COVID-19 diagnosis among PD patients was independently associated with functional impairment during COVID-19 [adjusted hazard ratio (HR) 2.46, 95% confidence interval (CI) 1.59–3.81], SARS-CoV-2 infection with the Delta variant (HR 2.23, 95% CI 1.55–3.21), and the need for respiratory support (HR 7.13, 95% CI 3.74–13.57) (p &lt; 0.01 for all). Conversely, the number of COVID-19 vaccines administered (HR 0.69, 95% CI 0.55–0.87; p = 0.001) and receiving corticosteroid therapy during COVID-19 (HR 0.72, 95% CI 0.54–0.97; p = 0.03) were associated with a decreased risk of death within 28 days after COVID-19 diagnosis. The number of functionally independent PD patients dropped from 94% at baseline to 63% during COVID-19 (p &lt; 0.01).

Conclusions

The COVID-19-related 28-day fatality rate was high among PD patients. The predictors of COVID-19-related death in PD patients were similar to those in hemodialysis patients. During COVID-19, PD patients commonly experienced functional deterioration.

Os desafios da pandemia e a vacinação covid-19 na população pediátrica com doenças renais

Resumo A vacina covid-19 confere proteção direta, reduz as taxas de transmissão do vírus e de novas variantes. No Brasil, estão liberadas para a população pediátrica as vacinas Pfizer/BioNTech e a CoronaVac, ambas seguras, eficazes e imunogênicas. Pacientes pediátricos com síndrome nefrótica e covid-19 têm curso clínico regular sem complicações relacionadas ao uso de esteroides ou vacinas. Esses pacientes, com ou sem imunossupressão, não apresentam maior risco de covid-19 grave e o tratamento com esteroides é seguro. Os pacientes com doença renal crônica têm covid-19 mais leve, sem necessidade de hospitalização. A resposta vacinal pode ser reduzida e/ou a duração dos anticorpos pós-vacinação pode ser menor do que na população geral. Entretanto, a vacina covid-19 está recomendada, considerando o risco de exposição. Acredita-se que pacientes com síndrome hemolítico-urêmica teriam maior risco de covid-19 grave. A vacina é recomendada, embora dados específicos sobre segurança e eficácia da vacina covid-19 sejam limitados. Há concordância que os benefícios da imunidade induzida superam quaisquer riscos da imunização. A vacina covid-19 é recomendada para crianças e adolescentes candidatos ao transplante renal ou já transplantados. Esses pacientes têm resposta imunológica reduzida após a vacina, entretanto ela é recomendada porque os benefícios superam qualquer risco dessa vacinação. A recomendação atual no Brasil é a vacina de tecnologia RNA mensageiro. O objetivo deste documento é levar aos nefrologistas pediátricos os conhecimentos mais recentes sobre a vacinação contra contra-19 em crianças com doenças renais.

SARS-CoV-2 spike protein antibody titers 6 months after SARS-CoV-2 mRNA vaccination among patients undergoing hemodialysis in Japan

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination is shown to prevent severe illness and death in hemodialysis (HD) patients, but the immune response to vaccines is reduced in this population. This study compared SARS-CoV-2 spike protein antibody titers between HD patients and healthy controls in Japan for up to 6 months following vaccination.

METHODS

A multi-institutional retrospective study at five clinics in Japan was conducted using 412 HD patients and 156 healthy controls who received two doses of the BNT162b2 (Pfizer-BioNTech) mRNA vaccine. Anti-SARS-CoV-2 spike protein S1 IgG antibody titers were measured at 1, 3, and 6 months after the second dose. The attenuation speed was calculated as slope (i.e., -β) using a linear mixed-effects model toward the log-transformed antibody titers.

RESULTS

The HD group had significantly lower month 1 antibody titers (Ab-titer-1) than the controls, and these remained lower through month 6 (95% CI: 2617.1 (1296.7, 5240.8) vs. 7285.4 (4403.9, 11,000.0) AU/mL at Ab-titer-1, and 353.4 (178.4, 656.3) vs. 812.0 (498.3, 1342.7) AU/mL at Ab-titer-6 (p < 0.001, respectively)). Lower log Ab-titer-1 levels in the HD group were significantly associated with a lower log Ab-titer-6 (0.90 [0.83, 0.97], p < 0.001). The -β values in the HD patients and healthy controls were -4.7 ± 1.1 and -4.7 ± 1.4 (year-1), respectively.

CONCLUSION

SARS-CoV-2 spike protein antibody titers were significantly lower in HD patients than in healthy controls at 1 (peak) and 6 months after the second vaccination. Low peak antibody titers contributed to low 6-month antibody titers.

Duration of immunity following full vaccination against SARS-CoV-2: a systematic review

Background

As vaccine roll-out continues across the globe as part of the efforts to protect humanity against SARS-CoV-2, concerns are increasingly shifting to the duration of vaccine-induced immunity. Responses to these concerns are critical in determining if, when, and who will need booster doses following full vaccination against SARS-CoV-2. However, synthesised studies about the durability of vaccine-induced immunity against SARS-CoV-2 are scarce. This systematic review synthesised available global evidence on the duration of immunity following full vaccination against SARS-CoV-2.

Methods

We searched through Psych Info, Web of Science, Scopus, Google Scholar, PubMed, and WHO COVID-19 databases for relevant studies published before December 2021. Five eligibility criteria were used in scrutinising studies for inclusion. The quality of the included studies was assessed based on Joana Briggs Institute’s (JBI) Critical Appraisal tool and Cochrane’s Risk of Bias tool—version 2 (RoB 2), while the reporting of the results was guided by the Synthesis Without Meta-analysis (SWiM) guidelines.

Results

Twenty-seven out of the 666 identified studies met the inclusion criteria. The findings showed that vaccine-induced protection against SARS-CoV-2 infections builds rapidly after the first dose of vaccines and peaks within 4 to 42 days after the second dose, before waning begins in subsequent months, typically from 3 to 24 weeks. Vaccine-induced antibody response levels varied across different demographic and population characteristics and were higher in people who reported no underlying health conditions compared to those with immunosuppressed conditions.

Conclusions

Waning of immunity against SARS-CoV-2 begins as early as the first month after full vaccination and this decline continues till the sixth month when the level of immunity may not be able to provide adequate protection against SARS-CoV-2. While the evidence synthesised in this review could effectively inform and shape vaccine policies regarding the administration of booster doses, more evidence, especially clinical trials, are still needed to ascertain, with greater precision, the exact duration of immunity offered by different vaccine types, across diverse population characteristics, and in different vulnerability parameters.

Registration

The protocol for this review was pre-registered with the International Prospective Register of Systematic Reviews [PROSPERO] (Registration ID: CRD420212818).

The Evolving Scenario of COVID-19 in Hemodialysis Patients

Coronavirus disease 2019 (COVID-19) is a rapidly changing disease. Therefore, in this study, to evaluate the evolution of COVID-19 in hemodialysis patients, we retrospectively compared patients affected by COVID-19 during the first pandemic waves of 2020 (from March to December 2020-Group 1) with patients with COVID-19 from September 2021 to February 2022 (Group 2) after the full completion of vaccination. Group 1 was constituted of 44 patients (69.3 ± 14.6 years), and Group 2 of 55 patients (67.4 ± 15.3 years). Among Group 2, 52 patients (95%) were vaccinated. Patients of Group 2, compared with Group 1, were more often asymptomatic (38 vs. 10%, p = 0.002) and reported less frequent fever and pulmonary involvement. At diagnosis, Group 2 showed a significantly higher number of lymphocytes and lower levels of circulating IL-6 (16 ± 13.3 vs. 41 ± 39.4 pg/mL, p = 0.002). Moreover, in Group 2, inflammatory parameters significantly improved after a few days from diagnosis. Patients of Group 2 presented a lower hospitalization rate (12.7 vs. 38%, p = 0.004), illness duration (18.8 ± 7.7 vs. 29.2 ± 19.5 days, p = 0.005), and mortality rate (5.4 vs. 25%, p = 0.008). Finally, responders to the vaccination (80% of vaccinated patients) compared with nonresponders showed a reduction in infection duration and hospitalization (5 vs. 40%, p = 0.018). In conclusion, we found that COVID-19 presentation and course in hemodialysis patients have improved over time after the implementation of vaccine campaigns. However, due to the evolving nature of the disease, active surveillance is necessary.

Durability of Humoral and Cellular Immunity after an Extended Primary Series with Heterologous Inactivated SARS-CoV-2 Prime-Boost and ChAdOx1 nCoV-19 in Dialysis Patients (ICON3)

The durability of a three-dose extended primary series of COVID-19 vaccine in dialysis patients remains unknown. Here, we assessed dynamic changes in SARS-CoV-2-specific humoral and cell-mediated immunity at baseline, 3 months, and 6 months after the extended primary series in 29 hemodialyzed (HD), 28 peritoneal dialyzed (PD) patients, and 14 healthy controls. Participants received two doses of inactivated SARS-CoV-2 vaccine followed by a dose of ChAdOx1 nCoV-19 vaccine. At 6 months, median anti-RBD IgG titers (IQR) significantly declined from baseline in the HD (1741 (1136−3083) BAU/mL vs. 373 (188−607) BAU/mL) and PD (1093 (617−1911) BAU/mL vs. 180 (126−320) BAU/mL) groups, as did the mean percent inhibition of neutralizing antibodies (HD: 96% vs. 81%; PD: 95% vs. 73%) (all p < 0.01). Age and post-vaccination serological response intensity were predictors of early humoral seroprotection loss. In contrast, cell-mediated immunity remained unchanged. In conclusion, humoral immunity declined substantially in dialysis patients, while cell-mediated immunity remained stable 6 months after the extended heterologous primary series of two inactivated SARS-CoV-2/ChAdOx1 nCoV-19 vaccine. A booster dose could be considered in dialysis patients 3 months after this unique regimen, particularly in the elderly or those with a modest initial humoral response.

The Effect of Age, Gender and Comorbidities Upon SARS-CoV-2 Spike Antibody Induction After Two Doses of Sinopharm Vaccine and the Effect of a Pfizer/BioNtech Booster Vaccine

Severe acute respiratory syndrome coronavirus (SARS-CoV)-2 emerged in China in 2019 and has since travelled the world infecting millions. SARS-CoV-2 causes Corona Virus Disease (COVID-19), that has to date taken over 4 million lives. The Kingdom of Bahrain’s vaccine roll-out has consisted of Sinopharm’s BBIBP-CorV (Sinopharm) and Pfizer/BioNtech’s BNT162b2 (Pfizer/BioNtech). Testing for SARS-CoV-2 anti-Spike (S) antibodies is a useful technique in estimating an individual’s immune protection against the infection. In this study we evaluated S antibody levels by electro-chemiluminescence immunoassay in 379 individuals double vaccinated with Sinopharm and 15 of whom were given a booster with the Pfizer/BioNtech vaccine. Among our double vaccinated cohort, we found a spectrum of S antibody levels. Indeed, we found that a significant proportion of individuals with low S antibody levels had clinical conditions, which were mainly immune-related disorders. Furthermore, a significant proportion of individuals with low S antibody levels were above 50 years of age. Finally, we observed a significant increase in S antibody levels after the Pfizer/BioNtech booster was administered. These findings reveal that while a large proportion of Sinopharm vaccinated individuals did not develop high levels of antibodies against the S protein, a booster dose of the Pfizer/BioNtech vaccine significantly enhances S antibody levels, revealing this “triple dose” vaccination strategy as a useful method of ensuring protective immunity against SARS-CoV-2.

Intranasal administration of a recombinant RBD vaccine induces long-term immunity against Omicron-included SARS-CoV-2 variants

The outbreak of coronavirus disease 2019 (COVID-19) has posed great threats to global health and economy. Several effective vaccines are available now, but additional booster immunization is required to retain or increase the immune responses owing to waning immunity and the emergency of new variant strains. The deficiency of intramuscularly delivered vaccines to induce mucosal immunity urged the development of mucosal vaccines. Here, we developed an adjuvanted intranasal RBD vaccine and monitored its long-term immunogenicity against both wild-type and mutant strains of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), including Omicron variants, in mice. Three-dose intranasal immunization with this vaccine induced and maintained high levels of neutralizing IgG antibodies in the sera for at least 1 year. Strong mucosal immunity was also provoked, including mucosal secretory IgA and lung-resident memory T cells (T_RM). We also demonstrated that the long-term persistence of lung T_RM cells is a consequence of local T-cell proliferation, rather than T-cell migration from lymph nodes. Our data suggested that the adjuvanted intranasal RBD vaccine is a promising vaccine candidate to establish robust, long-lasting, and broad protective immunity against SARS-CoV-2 both systemically and locally.

COVID-19 in dialysis: clinical impact, immune response, prevention, and treatment

The COVID-19 pandemic has profound adverse effects on the population on dialysis. Patients requiring dialysis are at an increased risk of SARS-CoV-2 infection and mortality, and many have experienced psychological distress as well as delayed or suboptimal care. COVID-19 survivors have prolonged viral shedding, but generally develop a robust and long-lasting humoral immune response that correlates with initial disease severity. However, protection against reinfection is incomplete. A growing body of evidence reveals delayed and blunted immune responses to SARS-CoV-2 vaccination. Administration of a third dose within 1 to 2 months of prime-boost vaccination significantly increases antibody levels, in particular in patients with poor initial responses. Patients on dialysis have inferior immune responses to adenoviral vector vaccines than to mRNA vaccines. The immunogenicity of the mRNA-1273 vaccine is markedly better than that of the BNT162b2 vaccine, most likely by virtue of its higher mRNA content. Despite suboptimal immune responses in patients on dialysis, preliminary data suggest that vaccination partially protects against infection and severe disease requiring hospitalization. However, progressive waning of immunity and emergence of SARS-CoV-2 variants with a high potential of immune escape call for a booster dose in all patients on dialysis 4 to 6 months after prime-boost vaccination. Patients with persistent poor vaccine responses may be candidates for primary prophylaxis strategies. In the absence of specific data in patients on dialysis, therapeutic strategies in the event of established COVID-19 must be extrapolated from evidence obtained in the population not on dialysis. Neutralizing monoclonal antibodies may be an attractive option after a high-risk exposure or during the early course of infection.

Diminished Short- and Long-Term Antibody Response after SARS-CoV-2 Vaccination in Hemodialysis Patients

Short-term studies have shown an attenuated immune response in hemodialysis patients after COVID-19-vaccination. The present study examines how antibody response is maintained after vaccination against SARS-CoV-2 in a large population of hemodialysis patients from six outpatient dialysis centers. We retrospectively assessed serum antibody levels against SARS-CoV-2 spike protein and nucleocapsid protein (electrochemiluminescence immunoassays, Roche Diagnostics) after COVID-19-vaccination in 298 hemodialysis and 103 non-dialysis patients (controls), comparing early and late antibody response. Compared to a non-dialysis cohort hemodialysis patients showed a favorable but profoundly lower early antibody response, which decreased substantially during follow-up measurement (median 6 months after vaccination). Significantly more hemodialysis patients had anti-SARS-CoV-2-S antibody titers below 100 U/mL (p < 0.001), which increased during follow-up from 23% to 45% but remained low in the control group (3% vs. 7%). In multivariate analysis, previous COVID-19 infections (p < 0.001) and female gender (p < 0.05) were significantly associated with higher early as well as late antibody vaccine response in hemodialysis patients, while there was a significant inverse correlation between patient age and systemic immunosuppression (p < 0.001). The early and late antibody responses were significantly higher in patients receiving vaccination after a SARS-CoV-2 infection compared to uninfected patients in both groups (p < 0.05). We also note that a higher titer after complete immunization positively affected late antibody response. The observation, that hemodialysis patients showed a significantly stronger decline of SARS-CoV-2 vaccination antibody titers within 6 months, compared to controls, supports the need for booster vaccinations to foster a stronger and more persistent antibody response.

Favorable Humoral Response to Third Dose of BNT162b2 in Patients Undergoing Hemodialysis

Patients undergoing hemodialysis are known to exhibit low humoral responses to vaccines against severe acute respiratory syndrome coronavirus 2. In this study, we aimed to elucidate the humoral response to the third dose of BNT162b2 (Pfizer) in patients undergoing hemodialysis. We included 279 patients undergoing hemodialysis (69 ± 11 years, 65% male, median dialysis vintage: 69 months) and 189 healthcare workers (45 ± 13 years, 30% male) who received the third dose of BNT162b2. Anti-spike immunoglobulin G (anti-S IgG) antibody levels were measured 3−4.5 months after the second dose and 3 weeks after the third dose and were compared. Despite a significant difference in anti-S IgG antibody levels after the second dose between the two groups (patients: median 215 U/mL and healthcare workers: median 589 U/mL; p < 0.001), no significant difference in anti-S IgG antibody levels after the third dose was observed (patients: median 19,000 U/mL, healthcare workers: median 21,000 U/mL). Except for dialysis vintage (ρ = 0.209, p < 0.001), no other factors correlated with anti-S IgG antibody levels after the third vaccine dose in patients undergoing hemodialysis. Therefore, a favorable response to the third dose of BNT162b2 was observed in patients undergoing hemodialysis, irrespective of their backgrounds.