Vaccination Course Research Articles

The effectiveness of vaccination for preventing hospitalisation with COVID-19 in regional Queensland: a data linkage study.

To estimate the effectiveness of vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) for protecting people in a largely coronavirus disease 2019 (COVID-19)-naïve regional population from hospitalisation with symptomatic COVID-19. Retrospective cohort study; analysis of positive SARS-CoV-2 polymerase chain reaction (PCR) test results linked with Central Queensland hospitals admissions data and Australian Immunisation Register data. Adult residents of Central Queensland, 1 January - 31 March 2022. Vaccine effectiveness (1 - relative risk of hospitalisation for vaccinated and unvaccinated people) with respect to protecting against hospitalisation with symptomatic COVID-19 after primary vaccination course only (two doses of an approved SARS-CoV-2 vaccine) and after a booster vaccine dose. Positive SARS-CoV-2 test results were recorded during 1 January - 31 March 2022 for 9682 adults, 7244 of whom had been vaccinated (75%); 5929 people were aged 40 years or younger (62%), 5180 were women (52%). Forty-seven people were admitted to hospital with COVID-19 (0.48%), four required intensive care (0.04%); there were no in-hospital deaths. Vaccine effectiveness was 69.9% (95% confidence interval [CI], 44.3-83.8%) for people who had received only a primary vaccination course and 81.8% (95% CI, 39.5-94.5%) for people who had also received a booster. Of the 665 Aboriginal and Torres Strait Islander adults with positive SARS-CoV-2 test results, 401 had been vaccinated (60%). Six Indigenous people were hospitalised with symptomatic COVID-19 (0.9%); vaccine effectiveness was 69.4% (95% CI, -56.5% to 95.8%) for Indigenous people who had received a primary vaccination course only or the primary course and a booster. The hospitalisation rate for Central Queensland people with PCR-confirmed Omicron variant SARS-CoV-2 infections during the first quarter of 2022 was low, indicating the protection afforded by vaccination and the value of booster vaccine doses.

COVID-19 vaccine effectiveness against symptomatic infection and hospitalisation in Belgium, July 2021 to May 2022.

BackgroundThe Belgian COVID-19 vaccination campaign aimed to reduce disease spread and severity.AimWe estimated SARS-CoV-2 variant-specific vaccine effectiveness against symptomatic infection (VEi) and hospitalisation (VEh), given time since vaccination and prior infection.MethodsNationwide healthcare records from July 2021 to May 2022 on testing and vaccination were combined with a clinical hospital survey. We used a test-negative design and proportional hazard regression to estimate VEi and VEh, controlling for prior infection, time since vaccination, age, sex, residence and calendar week of sampling.ResultsWe included 1,932,546 symptomatic individuals, of whom 734,115 tested positive. VEi against Delta waned from an initial estimate of 80% (95% confidence interval (CI): 80-81) to 55% (95% CI: 54-55) 100-150 days after the primary vaccination course. Booster vaccination increased initial VEi to 85% (95% CI: 84-85). Against Omicron, an initial VEi of 33% (95% CI: 30-36) waned to 17% (95% CI: 15-18), while booster vaccination increased VEi to 50% (95% CI: 49-50), which waned to 20% (95% CI: 19-21) 100-150 days after vaccination. Initial VEh for booster vaccination decreased from 96% (95% CI: 95-96) against Delta to 87% (95% CI: 86-89) against Omicron. VEh against Omicron waned to 73% (95% CI: 71-75) 100-150 days after booster vaccination. While recent prior infections conferred higher protection, infections occurring before 2021 remained associated with significant risk reduction against symptomatic infection. Vaccination and prior infection outperformed vaccination or prior infection only.ConclusionWe report waning and a significant decrease in VEi and VEh from Delta to Omicron-dominant periods. Booster vaccination and prior infection attenuated these effects.

Older adults and non-response to rabies post-exposure prophylaxis: Challenges and approaches.

Rabies vaccines are highly effective and immunogenic in most populations, including when used as rabies post-exposure prophylaxis (RPEP); however, there is mounting evidence that the immune response to rabies vaccines, though predicted to be adequate, may be lower in older adults. Despite this, there are no specific recommendations in Canadian guidance to monitor the serological response of older adults following RPEP. Furthermore, while Canadian guidance recommends the intramuscular route for RPEP vaccination, there is good evidence supporting the immunogenicity, effectiveness and safety of RPEP vaccination using the intradermal route. We present a case of an 87-year-old male with rabies exposure who failed to respond to two series of RPEP with intramuscular rabies vaccination but responded to a third series using intradermal vaccine administration and provide reasoning for subsequent management. This case is brought forward to prompt discussion and research as to the utility of completing serology in older adults receiving RPEP as well as vaccination strategies, including route of administration, in those who do not respond to an initial course of RPEP vaccination.

Safety of monovalent and bivalent BNT162b2 mRNA COVID-19 vaccine boosters in at-risk populations in Israel: a large-scale, retrospective, self-controlled case series study

COVID-19 continues to be a major health threat, particularly among at-risk groups, including individuals aged 60 years or older and people with particular medical conditions. Nevertheless, the absence of sufficient vaccine safety information is one of the key contributors to vaccine refusal. We aimed to assess the short-term safety profile of the BNT162b2 mRNA COVID-19 vaccine booster doses. In this self-controlled case series study, we used a database of members of the largest health-care organisation in Israel. We analysed the medical records of individuals at risk of COVID-19 complications who had received two doses of the monovalent BNT162b2 mRNA COVID-19 vaccine (tozinameran, Pfizer-BioNTech) as their primary course of vaccination and then also received BNT162b2 mRNA COVID-19 vaccine boosters between July 30, 2021, and Nov 28, 2022, as a monovalent first or second booster, or as a bivalent first, second, or third booster, or a combination of these. We included individuals who had active membership of the health-care organisation and who were alive (excluding COVID-19 deaths) throughout the entire study period. We excluded individuals who, during the study period, were either not active Clalit Health Services members or died of non-COVID-19 causes, and those who were infected with COVID-19 during the 7-day period after vaccination. Individuals' at-risk status was assessed on the day before the baseline period started. The primary outcome was non-COVID-19 hospitalisation for 29 adverse events that might be associated with vaccination. For each adverse event, we compared the risk difference of hospitalisation during a 28-day pre-vaccination baseline period versus during a 28-day post-vaccination period, using a non-parametric percentile bootstrap method. Of the 3 574 243 members of the health-care organisation, 1 073 110 received a first monovalent booster, 394 251 received a second monovalent booster, and 123 084 received a bivalent first, second, or third booster. Overall, we found no indication of an elevated risk of non-COVID-19 hospitalisation following administration of any of the booster vaccines (risk difference in events per 100 000 individuals: first monovalent booster -37·1 [95% CI -49·8 to -24·2]; second monovalent booster -37·8 [-62·2 to -13·2]; and bivalent booster -18·7 [-53·6 to 15·4]). Except for extremely rare elevated risks after the first monovalent booster-of myocarditis (risk difference 0·7 events per 100 000 individuals [95% CI 0·3-1·3]), seizures (2·2 [0·4-4·1]), and thrombocytopenia (2·6 [0·7-4·7])-we found no safety signals in other adverse events, including ischaemic stroke. This study provides the necessary vaccine safety assurances for at-risk populations to receive timed roll-out booster vaccinations. These assurances could reduce vaccine hesitancy and increase the number of at-risk individuals who opt to become vaccinated, and thereby prevent the severe outcomes associated with COVID-19. Israel Science Foundation and Israel Precision Medicine Partnership programme.

Some aspects of specific prevention of a new coronavirus infection caused by the SARS CoV-2 virus in the Samara region

The new coronavirus infection remains a significant medical and social event in the world, and only active immunization of the population with the achievement of the target level of vaccination coverage of at least 60% is able to stop its spread.Objective: to study the preliminary results of vaccination against a new coronavirus infection caused by the SARS CoV-2 virus in the Samara region.Materials and methods. The material of this study was the results of statistical monitoring of the incidence of a new coronavirus infection caused by the SARS CoV-2 virus in residents of the Samara region and data on the vaccination campaign. Statistical analysis included descriptive, comparative and interval estimation, as well as correlation analysis.Results. As of October 2022, 62.6% of the total population in the Samara region has been vaccinated against a new coronavirus infection caused by the SARS CoV-2 virus. Women predominated among those vaccinated – 60.51%. When analyzing the results of the vaccination campaign, statistically significant negative relationships were revealed between the proportion of vaccinated in a certain month and the incidence in the next three months, as well as between the accumulated percentage of vaccinated and the incidence in the next few months. At the same time, morbidity and vaccination in a normalized form for the population does not depend on the size of the population.Conclusions: Vaccination reduces the risk of a new coronavirus infection caused by the SARS CoV-2 virus in the Samara region by an average of 7.4 times. With the development of a manifest form of a new coronavirus infection caused by the SARS CoV-2 virus, in residents of the Samara region who have undergone a full course of vaccination, the risk of developing severe and extremely severe forms decreases by an average of 1.65 times, and deaths – by 1.71 times.

Comparative characteristics of the cellular immune response to SARS-CoV-2 during infection and post-vaccination

An important area of research concerns monitoring of immune response features in patients with SARS-CoV-2 infection as well as their analysis, as compared with characteristics of vaccine-mediated protection, in order to specify the determinants of cellular immune response. The aim of our work was to compare the state of cellular immune response in patients who underwent COVID-19, and in persons vaccinated with a peptide vaccine preparation. The study involved volunteers who suffered with COVID-19 of varying severity (n = 30), as well as persons who completed the full course of vaccination with the peptide vaccine (n = 27). For comparison, we took blood specimens from the volunteers before vaccination. Immunophenotyping of leukocytes was performed by the Lyse/No-Wash procedure (BD Bioscience, USA), and Cyto-Stat monoclonal antibodies (CD45-FITC, CD4-PE, CD8-ECD, CD3-PC5), CD45RA-PC7, CD45RO-PE (Beckman Coulter, USA), and analyzed with a DakoCytomation flow cytometer (Denmark). Determination of intracellular IFNγ (CD4+IFNγ+) was performed with the standard technique. Cytokine production was determined using reagent kits for detection of IFNγ, TNFα, IL-4, IL-8, IL-10 (Vector-Best JSC, Russia) with automatic enzyme immunoassay analyzer LAZURIT (Dynex Technologies, USA). As based on the results obtained, we have shown that cellular immunity was developed after vaccination and infection with COVID-19. However, the most pronounced immune response was recorded in the COVID-19 reconvalescents, i.e., more than 60% of these patients showed an increased number of CD4+T-memory helper cells (8.7 (0.5-12.1) % versus 0.3 (0.1-0.5) % in the comparison group, p < 0.05) as well as proportion of CD4+IFNγ+T lymphocytes (4.2 (1.8-4.3) % versus 0.4 (0-0.8) % in the comparison group, p < 0.05). Moreover, we revealed an increased functional reserve of cells in terms of TNFα, IL-8, IL-10 production. One month after vaccination of volunteers with the peptide-based preparation, the total pool of memory T lymphocytes was apparently dominated by CD8+T memory cells (CD45+CD8+CD45RA-CD45RO+). A significant increase was found in the average levels of CD4+IFNγ+ activated cells (8.2-fold), as well as in values of ConA-induced IL-4 production (3.3 (1.1-4.5) pg/mL, and 2.8 (1.7-3.9) pg/mL, respectively versus 1.3 (0.1-2.4) pg/mL in the control group, p < 0.05). The data obtained are in accordance with information available in the literature concerning development of cellular immune responses to SARS-CoV-2, which results from a past illness, or measures for the specific prevention of COVID-19. Further search for cellular correlates of protection against a new coronavirus infection will allow us to revise the current vaccination strategy and develop an optimal approach to COVID-19 prevention.

Relationship between anthropometric and body composition parameters and anti-SARS-CoV-2 specific IgG titers in females vaccinated against COVID-19 according to the heterologous vaccination course: A cohort study.

The aim of this cohort study was to evaluate the relationship between anthropometric and body composition parameters and anti-SARS-CoV-2 IgG titers in a group of females who were vaccinated against COVID-19 with two doses of ChAdOx1 vaccine and then boosted with the BNT162b2 vaccine. The study group consisted of 63 women. Basic demographic and clinical data were collected. To assess the anti-SARS-CoV-2 immunoglobulin G titers following the vaccination, five blood draws were performed: 1) before the first dose, 2) before the second dose, 3) 14-21 days after the primary vaccination, 4) before the booster, and 5) 21 days after the booster. Blood samples were analyzed using a two-step enzymatic chemiluminescent assay. Body mass index and body composition were evaluated using bioelectrical impedance analysis. To select the most distinguishing parameters and correlations between anthropometric and body composition parameters and anti-SARS-CoV-2 IgG titers, factor analysis using the Principal Component Analysis was conducted. Sixty-three females (mean age: 46.52 years) who met the inclusion criteria were enrolled. 40 of them (63.50%) participated in the post-booster follow-up. After receiving two doses of the ChAdOx1 vaccine, the study group's anti-SARS-CoV-2 IgG titers were 67.19 ± 77.44 AU/mL (mean ± SD), whereas after receiving a heterologous mRNA booster, the level of anti-SARS-CoV-2 IgG titers was about three-times higher and amounted to 212.64 ± 146.40 AU/mL (mean ± SD). Our data shows that seropositivity, obesity, non-fat-related, and fat-related body composition parameters all had a significant effect on the level of IgG titer after a two-dose vaccination of ChAdOx1. However, only non-fat-related and fat-related body composition parameters had a significant effect on the IgG titer after booster vaccination. COVID-19 infection before the first dose of vaccination is not related to IgG titer after booster administration. Body composition has a significant effect on the production of anti-SARS-CoV-2 IgG after booster vaccination in females.

COVID-19 vaccination-related myocarditis: a Korean nationwide study.

A comprehensive nationwide study on the incidence and outcomes of COVID-19 vaccination-related myocarditis (VRM) is in need. Among 44 276 704 individuals with at least 1 dose of COVID-19 vaccination, the incidence and clinical courses of VRM cases confirmed by the Expert Adjudication Committee of the Korea Disease Control and Prevention Agency were analyzed. COVID-19 VRM was confirmed in 480 cases (1.08 cases per 100 000 persons). Vaccination-related myocarditis incidence was significantly higher in men than in women (1.35 vs. 0.82 per 100 000 persons, P < 0.001) and in mRNA vaccines than in other vaccines (1.46 vs. 0.14 per 100 000 persons, P < 0.001). Vaccination-related myocarditis incidence was highest in males between the ages of 12 and 17 years (5.29 cases per 100 000 persons) and lowest in females over 70 years (0.16 cases per 100 000 persons). Severe VRM was identified in 95 cases (19.8% of total VRM, 0.22 per 100 000 vaccinated persons), 85 intensive care unit admission (17.7%), 36 fulminant myocarditis (7.5%), 21 extracorporeal membrane oxygenation therapy (4.4%), 21 deaths (4.4%), and 1 heart transplantation (0.2%). Eight out of 21 deaths were sudden cardiac death (SCD) attributable to VRM proved by an autopsy, and all cases of SCD attributable to VRM were aged under 45 years and received mRNA vaccines. Although COVID-19 VRM was rare and showed relatively favorable clinical courses, severe VRM was found in 19.8% of all VRM cases. Moreover, SCD should be closely monitored as a potentially fatal complication of COVID-19 vaccination.

A Three-Dose mRNA COVID-19 Vaccine Regime Produces Both Suitable Immunogenicity and Satisfactory Efficacy in Patients with Solid Cancers.

The recommended booster third dose of vaccination against COVID-19 in cancer patients seems reasonable to protect them against a severe disease course. A prospective study was designed to assess the immunogenicity, efficacy, and safety of COVID-19 vaccination in this cohort. Patients with solid malignancies on active treatment were followed up after the primary course and booster third dose of vaccination to assess their anti-SARS-CoV-2 S1 IgG levels, efficacy in the case of SARS-CoV-2 infection, and safety. Out of 125 patients receiving the primary course of vaccination, 66 patients received a booster third dose of mRNA vaccine, with a 20-fold increase in median anti-SARS-CoV-2 S1 IgG levels compared to Ab levels six months post-primary course of vaccination (p < 0.0001). After the booster third dose, anti-SARS-CoV-2 S1 IgG levels were comparable to healthy controls (p = 0.113). There was a decline in Ab levels 3 (p = 0.0003) and 6 months (p < 0.0001) post-third booster dose. No patients had either a severe disease course or a lethal outcome in the case of SARS-CoV-2 infection after the third booster dose. The third booster vaccination dose against COVID-19 in solid cancer patients triggers substantial immunogenicity and is safe and effective for preventing a severe COVID-19 disease course.

P19 INCIDENTAL DIAGNOSIS OF MASSIVE MOBILE LEFT VENTRICLE THROMBI FOLLOWING COVID–19 INFECTION IN A HEART FAILURE PATIENT

Abstract Background Intracardiac thrombus can be a complication of ischemic heart disease and cardiomyopathies. The advancements in imaging modalities have increased the capacity to diagnose this condition helping to reduce the associated complications (i.e. embolization). Previous reports suggest a possible link between intracardiac thrombosis and COVID–19 infection, especially in patients with severe “endotheliitis”, pneumonia, or myocarditis. COVID–19 effects on the cardiovascular system are partly evaluated. Venous and arterial thrombosis is commonly associated with COVID–19 but detection of intracardiac thrombus has not been frequently reported. Case Description: A 71–year–old woman, known to have a non–ischemic dilated cardiomyopathy with reduced ejection fraction (EF) and a previous transcatheter edge–to–edge mitral valve repair (MitraClip), was admitted after a routine echocardiogram showing new onset multiple, highly mobile, left ventricle (LV) masses. The patient, fully vaccinated against Sars–Cov–2, experienced a paucisymptomatic COVID–19 infection 1 month before, followed by a full recovery. A transthoracic echocardiogram performed 3 months showed no LV masses. On admission she was completely asymptomatic with no clinical signs of heart failure or systemic embolization. A multimodality imaging evaluation (contrast echocardiography, cardiac computed tomography, cardiac magnetic resonance) confirmed a severe dilation of the LV with severe EF reduction, and 3 mobile LV masses. The largest mass was adhered to the middle portion of the anterolateral wall (maximum diameter 49x15 mm). A diagnostic endomyocardial biopsy and cardiac surgery were excluded due to prohibitive embolic/procedural risk and an anticoagulant treatment with warfarin was started with a progressive reduction of the masses’ dimension at transthoracic echocardiography. Thus, a diagnosis of exclusion of LV thrombosis was made. After 2–week a complete resolution of the masses was documented with no clinical or embolic events. Conclusion The pro–thrombotic nature of COVID–19 infection is well known. This case demonstrates how vulnerable patients, i.e. those with heart failure, may experience thrombotic complications following non–severe COVID–19 infection and despite having completed the vaccine course. Although currently unconfirmed by dedicated clinical trials, more assiduous echocardiographic monitoring and/or the use of anticoagulant therapies could yield a benefit in selected patients.

The Impact of the Covid-19 Pandemic on Muslim Konkani Community of Thane District and Their Resilience

This welt of Covid-19 is likely to be felt for years to come. This paper focuses on the devastating effect of COVID-19 on the Muslim Konkani community of Thane Dist. and their grief and struggle. Social life eventually restarts and communal activities resume but the scar remains. This paper focuses on the human sufferings the pandemic and lockdown brought with it. Despite the fact that the crisis was world-wide, the impacts were territorially diverse. Detailed case studies and sufferings of people during pandemic and lockdown situation with many cumulative effects on economy and society. The mental health impacts such as anxiety and depression. How these people coped up to the increasing medical expenses and hospitalization. The struggle of people and their recovery from such situation, their survival and endurance. This study is important to understand about the healthcare facilities and community participation. It is based on in-depth case studies of people who have lost their family members/earning members to the deadly disease, few community workers and healthcare workers using snowball sampling method. The primary objective of this ethnographic study is to identify the impact of the crisis on households who lost a family member, and the vulnerable and precarious situation. However, when the recovery from COVID-19 aroused the resilience of a place is often determined by the existing strength of the local community. The living situations, financial conditions, religious obligations, and social distancing of Muslims during the COVID-19 pandemic and while vaccination course

Comparison of vaccination schedules for foot-and-mouth disease among cattle and sheep in Mongolia.

Vaccines are a critical tool for the control strategy for foot-and-mouth disease (FMD) in Mongolia where sporadic outbreaks regularly occur. A two-dose primary vaccination course is recommended for most commercial vaccines though this can be logistically challenging to deliver among nomadic pastoralist systems which predominate in the country. Although there is evidence that very high potency vaccines can provide prolonged duration of immunity, this has not been demonstrated under field conditions using commercially available vaccines. This study compared neutralizing titres to a O/ME-SA/Panasia strain over a 6-month period following either a two-dose primary course or a single double-dose vaccination among Mongolian sheep and cattle using a 6.0 PD50 vaccine. Titers were not significantly different between groups except in sheep at six-months post vaccination when the single double-dose group had significantly lower titers. These results indicate the single double-dose regimen may be a cost-effective approach for vaccination campaigns supporting FMD control in Mongolia.

Real-World Effectiveness of Nirmatrelvir/Ritonavir on Covid-19-Associated Hospitalization Prevention: A Population-Based Cohort Study in the Province of Québec, Canada.

The nirmatrelvir/ritonavir has shown to reduce COVID-19 hospitalization and death before Omicron but updated real-world evidence studies are needed. This study aimed to assess whether nirmatrelvir/ritonavir reduces the risk of COVID-19-associated hospitalization among high-risk outpatients. This was a retrospective cohort study of SARS-CoV-2-infected outpatients between March 15 and October 15, 2022, using data from the Québec clinico-administrative databases. Outpatients treated with nirmatrelvir/ritonavir were compared to infected ones not receiving nirmatrelvir/ritonavir using propensity-score matching. Relative risk of COVID-19-associated hospitalization occurring within 30 days following the index date was assessed using a Poisson regression. A total of 8,402 treated outpatients were matched to controls. Regardless of vaccination status, nirmatrelvir/ritonavir treatment was associated with a 69% reduced relative risk of hospitalization (RR: 0.31 [95%CI: 0.28; 0.36], NNT=13). The effect was more pronounced in outpatients with incomplete primary vaccination course (RR: 0.04 [95%CI: 0.03; 0.06], NNT=8), while no benefit was found in those with a complete primary vaccination course (RR: 0.93 [95%CI: 0.78; 1.08]). Subgroups analysis among high-risk outpatients with a primary vaccination course showed that nirmatrelvir/ritonavir treatment was associated with a significant decrease in relative risk of hospitalization in severely immunocompromised outpatients (RR: 0.66 [95%CI: 0.50; 0.89], NNT=16) and in high-risk outpatients aged 70 years and older (RR: 0.50 [95%CI: 0.34; 0.74], NNT=10) when the last dose of the vaccine was received at least six months ago. Nirmatrelvir/ritonavir reduces the risk of COVID-19-associated hospitalization among incompletely vaccinated high-risk outpatients and among some subgroups of completely vaccinated high-risk outpatients.

Relatively preserved functional capacity with standard COVID-19 vaccine regimen in People Living with HIV asymptomatic or with mild immunodeficiency

Abstract People living with HIV (PLWH) are at a higher risk of sever disease with SARS-CoV-2 virus infection. COVID-19 vaccines are effective in most PLWH, with significant reduction in the risk of severe disease or death when the standard 2-shot regimen is taken. However, suboptimal immune response to the standard course of vaccination is a concern for PLWH, especially for those with moderate to severe immunodeficiency. An additional dose is recommended as part of the extended primary series. In Taiwan, this additional dose is endorsed even for asymptomatic or mild immunodeficiency with CD4 counts &amp;gt;200/mm 3and suppressed virology. We aimed to investigate the immune responses with the additional dose in PLWH asymptomatic or with mild immunodeficiency. We collected peripheral blood mononuclear cells (PBMC) from 72 PLWH asymptomatic or with mild immunodeficiency and from 362 non-HIV subjects, after two and three shots respectively. Two shots elicited lower responses in PLWH, although the difference was statistically insignificant. They have comparable levels of neutralizing and anti-S antibodies and comparable effector CD4+ and CD8+ T cell responses. The 3 rdshot boosted the SARS-CoV-2 immunity significantly more in PLWH compared to the non-HIV people. Upon in vitro stimulation with extracted Wuhan strain SARS-CoV-2 proteins, CD8+ T cells from PLWH after 3 shots has more durable effector responses than the non-HIV controls with extended time of stimulation. This subtle difference between PLWH and non-HIV people implied immune exhaustion with two shots in non-HIV people. Slightly compromised immunity in PLWH indeed preserved the functional capacity for further response to the 3 rdshot or natural infection. The Research Center for Emerging Viral Infections receives support from The Featured Areas Research Center Program within the framework of the Higher Education Sprout Project by the Ministry of Education (MOE), Taiwan and NSTC 111-2634-F-182-001 from the National Science and Technology Council, Taiwan. This work was supported by Projects CMRPG3M1811 (CTH) from the Medical Research Project Fund, Chang Gung Memorial Hospital, Taiwan.

Timely course of SARS-CoV-2 infections and vaccinations in patients with hemato-oncological diseases: analysis of a real-life cohort

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has particularly impacted patients with hemato-oncological malignancies, as they showed not only a higher propensity for severe courses but also weaker immune responses after vaccination. Still, data on the influence of pandemic waves and vaccinations on outcomes are rare. This study aimed to analyze the timely course of infections and vaccinations in a real-life cohort of patients with hemato-oncological diseases. In this cohort study, 1817 patients with hemato-oncological diseases from 1 February 2020 to 15 December 2022 at the 'Franz Tappeiner' Hospital in Merano/Meran, Italy, were followed for SARS-CoV-2 infections and vaccinations. Of 1817 patients with hemato-oncological malignancies, 735 (40.5%) were infected at least once with SARS-CoV-2, and 1614 (88.8%) received one or more doses of the approved vaccinations. Patients receiving antineoplastic treatment had a lower SARS-CoV-2 infection rate [35.1% versus 41.0%; odds ratio (OR) 0.78, 95% confidence interval (CI) 0.64-0.95], but higher risk of hospitalization (13.4% versus 6.9%; OR 2.11, 95% CI 1.25-3.69) compared with untreated patients. Overall, the case fatality rate (CFR) was 3.4%. Unvaccinated patients were more prone to severe coronavirus disease 2019 (COVID-19) courses requiring hospitalization (OR 2.34, 95% CI 1.25-4.36) and had a higher CFR (7.3% versus 1.6%; OR 4.98, 95% CI 2.16-12.98) than their vaccinated counterparts. In the Delta wave, patients with two vaccinations had a lower infection risk (OR 0.18, 95% CI 0.10-0.35) and tendentially lower hospitalization rates (OR 0.25, 95% CI 0.05-1.29) than unvaccinated patients. In the Omicron wave, 345/1198 (28.8%) patients with three or more vaccinations had breakthrough infections, resulting in a similar risk for infection (OR 0.88, 95% CI 0.60-1.30) but numerically lower risk for hospitalization (24/345, 7.0%) than unvaccinated individuals (4/40, 10.0%). Scheduled visits were postponed in 128/335 (38.2%) patients due to COVID-19, and deferrals correlated with pandemic wave (P= 0.002) and vaccination status (P < 0.001). SARS-CoV-2 infections and outcomes differ between distinct phases of the pandemic. Vaccination with variant-specific vaccines should be prioritized as general protective measures are increasingly lifted.

The Omicron Variant of SARS-CoV-2 Virus: the Ability to Cause Disease in Persons with Immunity against COVID-19

During the COVID-19 pandemic the experts noted the emergence and periodic change of the dominant variants of the coronavirus (SARS-CoV-2) that caused the disease. The line B.1.1529, the omicron variant according to the WHO classification, became dominant in the fifth wave of the COVID-19 pandemic. The aim of the work is to analyze the properties of B.1.1529 (omicron) viruses that ensure its ability to cause disease in vaccinated or previously recovered from COVID-19. The fifth wave is characterized by the parallel distribution of the delta and omicron variants, with the domination of the latter. The omicron variant arose as a result of multiple passages of SARS-CoV-2 through the organisms of immunocompromised patients. If the delta variant is the most virulent for humans, the omicron variant is certainly the most infectious - the value of the basic reproductive number (R0) for it is ≈ 10.0, for the delta variant ≈ 6, 0. A person infected with the omicron variant is capable of transmitting the SARS-CoV-2 virus within a day. This is caused by a combination of N501Y and Q498R mutations in the omicron variant, which increase the affinity of the receptor-binding domain of the S1 subunit of the viral S protein for the ACE-2 receptor in the human lung. Mutations H655Y and N679K are located near the furin cleavage site, which in turn promotes accelerated cleavage of the S-protein and increases the level of infectiousness of the pathogen. The omicron variant is significantly superior to the delta variant in terms of ability to overcome the immunity caused by vaccination. The spread of the disease was not stopped by the fact that the number of people who completed the full course of vaccination at the beginning of the fifth wave in Russia reached 64%.Therefore, the achieved level of vaccination cannot be considered sufficient to stop the spread of this variant of the virus. It is shown in the article, that this indicator should be at least 80% to prevent the spread of the disease, and only if vaccination is carried out in a short time. However, it is possible that the mutational potential of the SARS-CoV-2 virus has not yet been exhausted, and the pandemic on the omicron variant will not end.

A third vaccine dose equalises the levels of effectiveness and immunogenicity of heterologous or homologous COVID-19 vaccine regimens, Lyon, France, December 2021 to March 2022.

BackgroundTo cope with the persistence of the COVID-19 epidemic and the decrease in antibody levels following vaccination, a third dose of vaccine has been recommended in the general population. However, several vaccine regimens had been used initially for the primary vaccination course, and the heterologous Vaxzevria/Comirnaty regimen had shown better efficacy and immunogenicity than the homologous Comirnaty/Comirnaty regimen.AimWe wanted to determine if this benefit was retained after a third dose of an mRNA vaccine.MethodsWe combined an observational epidemiological study of SARS-CoV-2 infections among vaccinated healthcare workers at the University Hospital of Lyon, France, with a prospective cohort study to analyse immunological parameters before and after the third mRNA vaccine dose.ResultsFollowing the second vaccine dose, heterologous vaccination regimens were more protective against infection than homologous regimens (adjusted hazard ratio (HR) = 1.88; 95% confidence interval (CI): 1.18-3.00; p = 0.008), but this was no longer the case after the third dose (adjusted HR = 0.86; 95% CI: 0.72-1.02; p = 0.082). Receptor-binding domain-specific IgG levels and serum neutralisation capacity against different SARS-CoV-2 variants were higher after the third dose than after the second dose in the homologous regimen group, but not in the heterologous group.ConclusionThe advantage conferred by heterologous vaccination was lost after the third dose in terms of both protection and immunogenicity. Immunological measurements 1 month after vaccination suggest that heterologous vaccination induces maximal immunity after the second dose, whereas the third dose is required to reach the same level in individuals with a homologous regimen.

Correlation between CD4 T-Cell Counts and Seroconversion among COVID-19 Vaccinated Patients with HIV: A Meta-Analysis.

To evaluate the potential factors for predicting seroconversion due to the coronavirus disease 2019 (COVID-19) vaccine in people living with HIV (PLWH). We searched the PubMed, Embase and Cochrane databases for eligible studies published from inception to 13th September 2022 on the predictors of serologic response to the COVID-19 vaccine among PLWH. This meta-analysis was registered with PROSPERO (CRD42022359603). A total of 23 studies comprising 4428 PLWH were included in the meta-analysis. Pooled data demonstrated that seroconversion was about 4.6 times in patients with high CD4 T-cell counts (odds ratio (OR) = 4.64, 95% CI 2.63 to 8.19) compared with those with low CD4 T-cell counts. Seroconversion was about 17.5 times in patients receiving mRNA COVID-19 vaccines (OR = 17.48, 95% CI 6.16 to 49.55) compared with those receiving other types of COVID-19 vaccines. There were no differences in seroconversion among patients with different ages, gender, HIV viral load, comorbidities, days after complete vaccination, and mRNA type. Subgroup analyses further validated our findings about the predictive value of CD4 T-cell counts for seroconversion due to COVID-19 vaccines in PLWH (OR range, 2.30 to 9.59). The CD4 T-cell counts were associated with seroconversion in COVID-19 vaccinated PLWH. Precautions should be emphasized in these patients with low CD4 T-cell counts, even after a complete course of vaccination.

Effectiveness of COVID-19 primary and booster vaccination in HIV-infected individuals

Effectiveness of COVID-19 primary and booster vaccination in HIV-infected individuals

Patients under medical conditions, immunogenicity and safety of covid-19 vaccines: a systematic review and meta-analysis

A comprehensive search was carried out in mainstream bibliographic databases or Medical Subject Headings, including ScienDirect, PubMed, Scopus, and ISI Web of Science. The search was applied to the articles that were published between January 2020 and early 2023 with strict literature search and screening processes, it yielded 14 articles from 373 articles of initial literature database. Among 14 study results, there was acceptable for immunogenicity (both humoral and cellular immune responses (a key response for the development of a vaccination-induced immunogenicity and safety in 11 studies (78.57 %), whereas acceptable potent immunogenicity was found in patients aged more than 40 years with chronic diseases, particularly, chronic respiratory diseases and coronary artery diseases. Only potent T-cell response was identified in one study. No significant difference in vaccine safety compared with healthy subjects and effective neutralizing antibodies (two doses completion) against SARS-CoV-2 (COVID-19) in patients older than 60 years with diabetes and/or hypertension were demonstrated after completion of COVID-19 vaccination. Immunogenicity (both humoral and cellular) and safety in aged people and individuals living with various chronic diseases (both infectious and non-infectious) is highlighted in this study. In conclusion, specified local and systemic AEs and unsolicited AEs, AESI, and SAEs after each vaccination and after the second dose should be monitored. Recording the adverse events of special interest (AESI) and serious adverse events (SAEs) throughout the patients’ vaccination course should be performed and can decrease COVID-19 vaccination hesitancy in these persons.