ABSTRACT
BACKGROUND AND AIMS: Although vaccination against COVID-19 infection in dialysis patients is an urgent issue of worldwide concern, literature data regarding the antibody level and their kinetics over time and the efficacy towards complete COVID-19 vaccination and booster dose in these patients is inconclusive. METHOD: We retrospectively assessed the response to COVID-19 vaccination, after the completion of vaccine series and after a booster dose in haemodialysis (HD) patients. IgG antibodies to the spike protein S1 subunit of SARS-CoV-2 were measured using ELISA at least 15 days after completion of a vaccination series, 1 month and finally 15-30 days after the booster dose. RESULTS: Among the 28 vaccinated HD patients (mean age = 59.8 years, 100% male) with two doses of mRNA vaccine, a seroconversion was documented in all the patients (100%) with a median antibody titre of 3270.6 U/mL (IQR: 94-40.000). We recorded 9 out of 28 early responders (peak level at 2 weeks) and 19/28 late responders (peak level at 1 month). The early responders were younger (56.25 years versus 61.63;P = 0.07), without cardiovascular history (88% versus 44%;P = 0.042) or diabetes (100% versus 63%;P = 0.042), compared with late responders. On multivariate analysis, combined haemoperfusion and haemodialysis (HR = 0.167, 95% confidence interval: 0.034-0.826;P = 0.028) was an independent prognostic factor for early responders. After 6 months, all the patients received a booster mRNA dose. The patients presented median antibody levels of 33.939 U/mL (IQR: 1112-181.223), much higher titre than the first peak. Finally, four patients, all from the late responders group, presented COVID-19 infection during the vaccination period (two patients in the early period <1 month and two patients in the late period >5 months). CONCLUSION: HD patients develop a substantial humoral response against SARS-CoV2 and the booster dose much higher response. The early responders presented more rapidly and more efficacious antibody levels, while the combined haemoperfusion and haemodialysis emerged as a positive predictor factor.
ABSTRACT
BACKGROUND AND AIMS: Immunosuppressed patients are in general less likely to achieve a detectable antibody response to SARS-CoV-2 after the primary doses of vaccine administration. However, there are limited data for the effect of a third booster dose in this patient population, especially for those with vasculitides and renal involvement treated with rituximab (RTX). METHOD: We retrospectively assessed the antibody responses to SARS-CoV-2 vaccination, after completion of the primary vaccine series (two doses) and after the booster third dose, in patients with vasculitides and renal involvement. IgG antibodies to the spike protein S1 subunit of SARS-CoV-2 were measured using ELISA >1 month after completion of the primary vaccination series (two doses of Pfizer or AstraZeneca vaccines) and 15-30 days after the third booster dose (Pfizer, given 3-6 months after the second dose). RESULTS: We included 20 patients with vasculitis [AAV, n = 16 (80%), IgAV, n = 4 (20%)] and renal involvement. All patients received immunosuppressives, including RTX (80%), MMF/AZA (15%), cyclophosphamide (5%), while half of patients were on glucocorticoids. The seroconversion rate after the primary two doses (Pfizer n = 8/16, Astra-Zeneca n = 1/1) was 53%, which increased to 67% after the third booster dose (Pfizer, n = 12/18). Similarly, the median antibody titers increased from 451 U/mL [interquartile range (IQR) 81-10.845] after the second dose to 1016 U/mL (IQR: 64- 37.568) after the booster dose. Regarding patients treated with RTX, the respective response rates after the second and third dose were 58% and 62%. Seropositive patients after the third dose tended to have lower previous cumulative exposure to RTX compared with seronegative ones (4.55 versus 5.5 g, P = .62, respectively). No vaccine side effects or disease relapses were noted after the three vaccine doses. CONCLUSION: In our patient cohort with systemic vasculitis and renal involvement treated mainly with RTX, a third booster vaccine dose increased the seropositivity rate from 53% to 67%. Nevertheless, one-third of patients did not achieve seroconversion. Whether a fourth booster dose could benefit these patients is still unknown.
ABSTRACT
The outbreak of the COVID-19 pandemic in 2020 affected people mobility worldwide. As a result, both international and domestic tourists almost completely cancelled their bookings, airlines cancelled most of their flights, almost all in-person meetings and events were suspended and PCO’s faced vast economic losses, as their turnover was reduced by over 75% for 2020, with the visitors/attendees decreased by over 90%. The aim of this paper was to investigate the extent to which new technologies were used in organizing and conducting digital events during the pandemic period and their overall impact on the congress market. For this we conducted both a primary and a secondary research;primary data were collected by interviewing the administrative personnel of Hotels, PCO’s, DMC’s, and Audiovisual companies and secondary data were obtained by reviewing journals, historical records, relevant studies conducted by tourism associations and also UNWTO statistics. Our results confirmed that there was a transition of MICE tourism to a new digital environment, in terms of organization of meetings and events and the use of technology throughout their operation. We believe that our study will provide evidence that technology has an important role in conference organization and management in the post-COVID-19 era. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.