T-Cell Response and Antibody Production Induced by the COVID-19 Booster Vaccine in Japanese Chronic Kidney Disease Patients Treated with Hemodialysis.

Humoral and cellular responses are critical in understanding immune responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. Here, we evaluated these responses in hemodialysis (HD) patients after the booster vaccination. SARS-CoV-2 immunoglobulin (IgG) levels, neutralizing antibody titers, and the T-SPOT®.COVID test (T-SPOT) were measured prior to, three weeks after, and three months after the booster administration. The HD group had significantly higher SARS-CoV-2 IgG levels and neutralizing antibody titers against the original strain at three weeks and three months after the booster vaccination compared to the control group, albeit the HD group had lower SARS-CoV-2 IgG levels and neutralizing antibody titers before the booster administration. Moreover, the HD group had significantly higher T-SPOT levels at all three time points compared to the control group. The HD group also had significantly higher local and systemic adverse reaction rates than the control group. By booster vaccination, HD patients could acquire more effective SARS-CoV-2-specific humoral and cellular immunity than the control group.

Association between a low response to rubella vaccination and reduced anti-severe acute respiratory syndrome coronavirus 2 immune response after vaccination with BNT162b2: a cross-sectional study.

OBJECTIVES: Some vaccinated individuals fail to acquire an adequate immune response against infection. We aimed to determine whether mRNA severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination could induce a sufficient immune response against SARS-CoV-2 in low responders to other vaccinations. METHODS: Using data from health-care workers who received two doses of the BNT162b2 vaccine (BioNTech/Pfizer), we conducted a single-centre, cross-sectional study to determine whether low responders to measles, rubella, and hepatitis B virus (HBV) vaccinations could acquire sufficient antibodies after SARS-CoV-2 vaccination. From May 2021 to June 2021, participants were tested for anti-SARS-CoV-2 spike (anti-S) IgG antibodies at least 2 weeks after the second dose of BNT162b2. The association between a low response to measles, rubella, and HBV vaccinations and the post-vaccination anti-S IgG titre was evaluated using the multivariable linear regression analysis. RESULTS: All 714 participants were positive for the anti-S IgG titre (≥50.0 AU/mL) after two doses of BNT162b2 (median, 7126.8 AU/mL; interquartile range, 4496.2-11 296.8). There were 323 (45.2%), 131 (18.3%), and 43 (6.0%) low responders to measles, rubella, and HBV vaccinations, respectively. In the multivariable linear regression analysis, low responders to rubella vaccination had significantly low acquisition of the anti-S IgG titre after two doses of the BNT162b2 vaccine (standardized coefficient ß, -0.110; 95% CI, -0.175 to -0.044). CONCLUSIONS: A low response to rubella vaccination is a potential predictor of a reduced response to SARS-CoV-2 vaccination. Further studies are needed to determine whether a low response to rubella vaccination is associated with the durability of SARS-CoV-2 vaccination-induced immune response.

SARS-CoV-2 Infection upon Leaving the Tokyo 2020 Olympic and Paralympic Games.

Objective Just before the Tokyo 2020 Olympic and Paralympic Games in Japan, the number of people infected with coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), started to increase at an unprecedented rate. This study investigated the effectiveness of vaccines in large-scale sporting events under difficult circumstances, such as during adherence to a bubble system and confinement inside the Olympic/Paralympic Village. Methods In collaboration with medical clinics inside and outside the Village, a prospective cohort study was conducted among overseas participants using the results of polymerase chain reaction (PCR) tests for SARS-CoV-2 upon leaving Japan. Results A total of 12,072 foreign participants were enrolled, 13 (0.11%) of whom had a positive PCR test result. None of these cases were broadcasters or members of the press, were tested outside the Olympic Village, or had a history of COVID-19 infection. The effectiveness of full vaccination and vaccination at least once (≥14 days ago) was 74% (95% confidence interval [CI]: 6-93%) and 81% (95% CI: 30-95%), respectively. Three breakthrough infections with the Delta variant were observed in 6,485 fully vaccinated participants (0.05%). The positivity rate was 0.09% among adherents to the bubble system and 0.28% among non-adherents, but this difference was not significant. Conclusion These findings indicate that even huge sporting events such as the Olympic and Paralympic Games can proceed while pandemics are ongoing in the host country by combining countermeasures such as vaccination, frequent testing, social distancing, and adherence to a bubble system.

Association between low response to rubella vaccination and reduced anti-SARS-CoV-2 immune response after vaccination with BNT162b2: A cross-sectional study

Objectives Some vaccinated individuals fail to acquire an adequate immune response against infection. We aimed to determine whether messenger-RNA severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination could induce sufficient immune response against SARS-CoV-2 in low responders to other vaccinations. Methods Using data from healthcare workers who received two doses of the BNT162b2 vaccine (BioNTech, Pfizer), we conducted a single-centre cross-sectional study to determine whether low responders to measles, rubella, and hepatitis B virus (HBV) vaccinations could acquire sufficient antibodies after SARS-CoV-2 vaccination. From May 2021 to June 2021, participants were tested for anti-SARS-CoV-2 spike immunoglobulin G (anti-S IgG) antibody at least two weeks after the second dose of BNT162b2. The association between low response to measles, rubella, and HBV vaccinations and the post-vaccination anti-S IgG titre was evaluated using multivariable linear regression analysis. Results All 714 participants were positive for the anti-S IgG titre (≥50.0 AU/mL) after two doses of BNT162b2 (median: 7,126.8 AU/mL, interquartile range: 4,496.2–11,296.8). There were 323 (45.2%), 131 (18.3%), and 43 (6.0%) low responders to measles, rubella, and HBV vaccinations, respectively. In the multivariable linear regression analysis, low responders to rubella vaccination had a significantly low acquisition of anti-S IgG titre after two doses of the BNT162b2 vaccine (standardised coefficient β = −0.110: 95% confidence interval: −0.175 to −0.044). Conclusions Low response to rubella vaccination is a potential predictor of reduced response to SARS-CoV-2 vaccination. Further studies are needed to determine whether a low response to rubella vaccination is associated with the durability of SARS-CoV-2 vaccination-induced immune response.

Investigation for the efficacy of COVID-19 vaccine in Japanese CKD patients treated with hemodialysis

Background Dialysis patients are predisposed to severe disease and have a high mortality rate in coronavirus disease 2019 (COVID-19) due to their comorbidities and immunocompromised conditions. Therefore, dialysis patients should be prioritized for vaccination. This study aimed to examine how long the effects of the vaccine are maintained and what factors affect antibody titers. Methods Hemodialysis patients (HD group) and age- and sex-matched non-dialysis individuals (Control group), receiving two doses of BNT162b2 vaccine, were recruited through the Japanese Society for Dialysis Therapy (JSDT) Web site in July 2021. Anti-SARS-CoV-2 immunoglobulin (IgG) (SARS-CoV-2 IgG titers) was measured before vaccination, 3 weeks after the first vaccination, 2 weeks after the second vaccination, and 3 months after the second vaccination, and was compared between Control group and HD group. Factors affecting SARS-CoV-2 IgG titers were also examined using multivariable regression analysis and stepwise regression analysis (least AIC). In addition, we compared adverse reactions in Control and HD groups and examined the relationship between adverse reactions and SARS-CoV-2 IgG titers. Results Our study enrolled 123 participants in the Control group (62.6% men, median age 67.0 years) and 206 patients in the HD group (64.1% men, median age 66.4 years). HD group had significantly lower SARS-CoV-2 IgG titers at 3 weeks after the first vaccination (p < 0.0001), 2 weeks after second vaccination (p = 0.0002), and 3 months after the second vaccination (p = 0.045) than Control group. However, the reduction rate of SARS-CoV-2 IgG titers between 2 weeks and 3 months after the second vaccination was significantly smaller in HD group than in Control (p = 0.048). Stepwise regression analysis revealed that dialysis time was identified as the significant independent factors for SARS-CoV-2 IgG titers at 2 weeks after the second vaccination in HD group (p = 0.002) and longer dialysis time resulted in higher maximum antibody titers. The incidences of fever and nausea after the second vaccination were significantly higher in the HD group (p = 0.039 and p = 0.020). Antibody titers in those with fever were significantly higher than those without fever in both groups (HD: p = 0.0383, Control: p = 0.0096). Conclusion HD patients had significantly lower antibody titers than age- and sex-matched non-dialysis individuals over 3 months after vaccination. Dialysis time was identified as a factor affecting SARS-CoV-2 IgG titers in HD group, with longer dialysis time resulting in higher maximum SARS-CoV-2 IgG titers.

Risk factors associated with hospitalization in patients with asymptomatic or mild COVID-19 in public accommodation facilities in Tokyo.

INTRODUCTION: In Japan, patients with coronavirus disease 2019 (COVID-19) who do not require medical intervention are provided care in recovery accommodation facilities (RAFs). However, some patients may require hospitalization if their symptoms become more severe during their stay. We conducted an observational study using epidemiological data of patients with COVID-19 admitted to RAFs in Tokyo. METHODS: This was an observational cohort study using data from COVID-19 patients admitted to one of the RAFs in Tokyo from December 2020 to November 2021. Admissions to the facilities were limited to patients with asymptomatic or mild COVID-19 with no underlying disease or at least stable underlying disease at the time of admission. Patients were hospitalized when they required oxygen administration or when they had, or persistent fever, or severe respiratory symptoms. We evaluated the association between hospitalization and the risk factors for hospitalization using a Cox regression model. RESULTS: The number of patients with COVID-19 admitted to the RAF was 6176. The number of hospitalized patients was 393 (6.4%), and the median length of stay was 5.50 days (IQR: 4.50, 6.50). In the Cox regression analysis, the hazard ratio increased with age and was significantly higher among patients aged >60 years (HR = 10.23, 95% CI: 6.72-15.57) than those in other age groups. This trend is similar to that observed in the sensitivity analysis. CONCLUSION: Patients with diabetes, the elderly, obesity, and medications for gout and psychiatric diseases may be at a high risk of hospitalization. In particular, an age over 60 years was strongly associated with hospitalization.

Committee report: Questionnaire survey on the treatment of COVID-19 in patients receiving dialysis therapy.

Background: Patients with coronavirus disease 2019 (COVID-19) who receive dialysis therapy develop more severe disease and have a poorer prognosis than patients who do not. Although various data on the treatment of patients not receiving dialysis therapy have been reported, clinical practice for patients on dialysis is challenging as data is limited. The Infection Control Committee of the Japanese Society for Dialysis Therapy decided to clarify the status of treatment in COVID-19 patients on dialysis. Methods: A questionnaire survey of 105 centers that had treated at least five COVID-19 patients on dialysis was conducted in August 2021. Results: Sixty-six centers (62.9%) responded to the questionnaire. Antivirals were administered in 27.7% of facilities treating mild disease (most patients received favipiravir) and 66.7% of facilities treating moderate disease (most patients with moderate or more severe conditions received remdesivir). Whether and how remdesivir is administered varies between centers. Steroids were initiated most frequently in moderate II disease (50.8%), while 43.1% of the facilities initiated steroids in mild or moderate I disease. The type of steroid, dose, and the duration of administration were generally consistent, with most facilities administering dexamethasone 6 mg orally or 6.6 mg intravenously for 10 days. Steroid pulse therapy was administered in 48.5% of the facilities, and tocilizumab was administered in 25.8% of the facilities, mainly to patients on ventilators or equivalent medications, or to the cases of exacerbations. Furthermore, some facilities used a polymethylmethacrylate membrane during dialysis, nafamostat as an anticoagulant, and continuous hemodiafiltration in severe cases. There was limited experience of polymyxin B-immobilized fiber column-direct hemoperfusion and extracorporeal membrane oxygenation. The discharge criteria for patients receiving dialysis therapy were longer than those set by the Ministry of Health, Labor and Welfare in 22.7% of the facilities. Conclusions: Our survey revealed a variety of treatment practices in each facility. Further evidence and innovations are required to improve the prognosis of patients with COVID-19 receiving dialysis therapy.