Vaccine Breakthrough Research Articles

Transcriptomic study reveals lncRNA-mediated downregulation of innate immune and inflammatory response in the SARS-CoV-2 vaccination breakthrough infections.

The emergence of multiple variants of concerns (VOCs) with higher number of Spike mutations have led to enhanced immune escape by the SARS-CoV-2. With the increasing number of vaccination breakthrough (VBT) infections, it is important to understand the possible reason/s of the breakthrough infections. We performed transcriptome sequencing of 57 VBT and unvaccinated COVID-19 patients, followed by differential expression and co-expression analysis of the lncRNAs and the mRNAs. The regulatory mechanism was highlighted by analysis towards repeat element distribution within the co-expressed lncRNAs, followed by repeats driven homologous interaction between the lncRNAs and the promoter regions of genes from the same topologically associated domains (TAD). We identified 727 differentially expressed lncRNAs (153 upregulated and 574 downregulated) and 338 mRNAs (34 up- and 334 downregulated) in the VBT patients. This includes LUCAT1, MALAT1, ROR1-AS1, UGDH-AS1 and LINC00273 mediated modulation of immune response, whereas MALAT1, NEAT1 and GAS5 regulated inflammatory response in the VBT. LncRNA-mRNA co-expression analysis highlighted 34 lncRNAs interacting with 267 mRNAs. We also observed a higher abundance of Alu, LINE1 and LTRs within the interacting lncRNAs of the VBT patients. These interacting lncRNAs have higher interaction with the promoter region of the genes from the same TAD, compared to the non-interacting lncRNAs with the enrichment of Alu and LINE1 in the gene promoter. Significant downregulation and GSEA of the TAD gene suggest Alu and LINE1 driven homologous interaction between the lncRNAs and the TAD genes as a possible mechanism of lncRNA-mediated suppression of innate immune/inflammatory responses and activation of adaptive immune response. The lncRNA-mediated suppression of innate immune/inflammatory responses and activation of adaptive immune response might explain the SARS-CoV-2 breakthrough infections with milder symptoms in the VBT. Besides, the study also highlights repeat element mediated regulation of genes in 3D as another possible way of lncRNA-mediated immune-regulation modulating vaccination breakthroughs milder disease phenotype and shorter hospital stay.

A booster hepatitis B vaccine for children with maternal HBsAg positivity before 2 years of age could effectively prevent vaccine breakthrough infections

BackgroundThe long-term protective effect of hepatitis B vaccine (HepB), the incidence of hepatitis B virus (HBV) vaccine breakthrough infections (VBIs), and whether a booster HepB is necessary remain to be clarified in children born to mothers with chronic HBV infection.MethodsBased on a long-term follow-up prospective cohort of 1177 hepatitis B surface antigen (HBsAg)-positive mothers and their paired infants which was established from 2009 to 2011, total 454 children with immunoprophylaxis success as determined by postvaccination serologic testing (PVST) at 7 months old were included in this study. Among the 454 children, 246 never had a booster HepB, and 208 children received a booster HepB from 1 to 5 years of age. Multivariate logistic regression analysis was used to analyse the risk factors for HBV VBIs.ResultsThe hepatitis B surface antibody (anti-HBs) levels declined sharply from 7 months to 2 years old, and the anti-HBs seronegative rate in the children increased significantly from 2 years old. A total of 31 (6.83%) of the 454 children experienced VBIs, of which 7 had overt and 7 had occult HBV infections. Notably, 14 (45.16%) of the 31 children with VBIs were diagnosed at 2 years old, and all of them had anti-HBs positivity (> 10 mIU/mL) at 1 year old. Maternal hepatitis B e antigen (HBeAg) positivity, higher HBV DNA and HBsAg levels, lower initial infant anti-HBs levels and not receiving a booster HepB were independent risk factors for VBIs. The incidence of VBIs was significantly lower in children with a booster HepB than in nonboosted children (0.50 vs. 11.90%, P < 0.001), and none of the boosted children developed overt or occult HBV infection. The anti-HBs levels of 76.67% for the children with VBIs in the nonboosted group indicated positivity before VBIs was detected.ConclusionsAfter the primary full immunization with HepB, children born to mothers with chronic HBV infection, especially the children with maternal HBeAg positivity, high HBV DNA levels, high HBsAg levels and/or low initial infant anti-HBs levels, were at a high risk of VBIs, and a booster HepB for these children before 2 years old, instead of when their anti-HBs level is < 10 mIU/mL, could reduce the incidence of VBIs.

Review of Developments in Combating COVID-19 by Vaccines, Inhibitors, Radiations, and Nonthermal Plasma.

Global society has been highly pressured by the COVID-19 pandemic, which has exposed vulnerabilities in supply chains for disinfection products, personal protective equipment, and medical resources worldwide. It is critically necessary to find effective treatments and medications for these viral infections. This review summarizes and emphasizes critical features of recent breakthroughs in vaccines, inhibitors, radiations, and innovative nonthermal atmospheric plasma (NTAP) technologies to inactivate COVID-19. NTAP has emerged as an effective, efficient, and safe method of viral inactivation. NTAP can be used to inactivate viruses in an environmentally friendly manner, as well as activate animal and plant viruses in a variety of matrices. Researchers and engineers desire to help the medical world deal with the ongoing COVID-19 epidemic by establishing techniques that make use of widely available NTAP technologies. NTAP technology is not dependent on viral strain, and it does not necessitate months or years of research to develop specific vaccines for each novel or arising viral disease. We believe the NTAP is a highly promising technique for combating COVID-19 and other viruses. Thus, NTAP technology could be a significant breakthrough in the near future in assisting humans in combating COVID-19 infections. We hope that this review provides a platform for readers to examine the progress made in the fight against COVID-19 through the use of vaccines, inhibitors, radiation, and NTAP.

The Four Ws of the Fourth Dose COVID-19 Vaccines: Why, Who, When and What.

With the emergence of SARS-CoV-2 variants, vaccine breakthrough is a major public health concern. With evidence of reduced neutralizing antibody activity against Omicron variants and fading antibody level after the third-dose booster vaccine, there are suggestions of a fourth-dose booster vaccine. In this review, the benefits of a fourth-dose booster is evaluated from four perspectives, including the effectiveness of the booster dose against virus variants (Why), susceptible groups of individuals who may benefit from additional booster dose (Who), selection of vaccine platforms to better enhance immunity (What) and appropriate intervals between the third and fourth booster dose (When). In summary, a fourth dose can temporarily boost the immune response against SARS-CoV-2 variants and can be considered for specific groups of individuals. A heterologous vaccine strategy using mRNA vaccine in individuals primed with inactivated vaccine may boost immunity against variants. The timing of the fourth dose should be individualized but an interval of 4 months after the third-dose booster is appropriate. A universal fourth booster dose is not necessary.

Modelling COVID-19 vaccine breakthrough infections in highly vaccinated Israel-The effects of waning immunity and third vaccination dose.

In August 2021, a major wave of the SARS-CoV-2 Delta variant erupted in the highly vaccinated population of Israel. The transmission advantage of the Delta variant enabled it to replace the Alpha variant in approximately two months. The outbreak led to an unexpectedly large proportion of breakthrough infections (BTI)-a phenomenon that received worldwide attention. Most of the Israeli population, especially those aged 60+, received their second dose of the vaccination four months before the invasion of the Delta variant. Hence, either the vaccine induced immunity dropped significantly or the Delta variant possesses immunity escaping abilities, or both. In this work, we model data obtained from the Israeli Ministry of Health, to help understand the epidemiological factors involved in the outbreak. We propose a mathematical model that captures a multitude of factors, including age structure, the time varying vaccine efficacy, time varying transmission rate, BTIs, reduced susceptibility and infectivity of vaccinated individuals, protection duration of the vaccine induced immunity, and the vaccine distribution. We fitted our model to COVID-19 cases among the vaccinated and unvaccinated, for <60 and 60+ age groups, and quantified the transmission rate, the vaccine efficacy over time and the impact of the third dose booster vaccine. The peak transmission rate of the Delta variant was found to be 2.14 times higher than that of the Alpha variant. The two-dose vaccine efficacy against infection dropped significantly from >90% to ~40% over 6 months. We further performed model simulations and quantified counterfactual scenarios examining what would happen if the booster had not been rolled out. We estimated that approximately 4.03 million infective cases (95%CI 3.19, 4.86) were prevented by vaccination overall, and 1.22 million infective cases (95%CI 0.89, 1.62) averted by the booster.

Absence of antibody responses to SARS-CoV-2 N protein in COVID-19 vaccine breakthrough cases.

Understanding the risk factors for breakthrough coronavirus disease 2019 (COVID-19) (BC19) is critical to inform policy. Herein, we assessed Delta (Lineage B.1.617.2) variant-specific effectiveness of the BNT162b2 (Pfizer) vaccine and characterized Delta-driven BC19 cases (fully vaccinated individuals who get infected) with known-time-since-vaccination. In this longitudinal prospective study (January 21-October 30, 2021), 90 naïve and 15 convalescent individuals were enrolled at the initiation of vaccination. Samples from 27 unvaccinated individuals with previous laboratory-confirmed COVID-19 diagnosis were collected at a single time point. Longitudinal serology profile (antibodies against severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2] S and N proteins) and live-virus-based neutralization capacities were assessed while controlling for age. Sex, age, history of reactions to the COVID-19 vaccine, and viral neutralization capacities were identified as significant risk factors for breakthrough COVID-19. At 8 months postvaccination, male sex, individuals ⩾65 years of age, and individuals who experienced noticeable side effects with the COVID-19 vaccine were at 5.47 (p-value = 0.0102), 4.33 (p-value = 0.0236), and 4.95 (p-value = 0.0159) fold greater risk of BC19 as compared to their peers, respectively. Importantly, every five-fold increase in viral neutralization capacities (by live-virus-based assays) was significantly associated with ~4-fold reduction in the risk occurrence of breakthrough COVID-19 (p-value = 0.045). Vaccine boosting remarkably increased these viral neutralization capacities by 16.22-fold (p- value = 0.0005), supporting the importance of the BNT162b2 booster in efforts to control the incursion of future variants into the population at large. Strikingly, BC19 cases exhibited a delayed/absent antibody response to the N protein, suggesting limited exposure to the virus. Since antibodies against N protein are widely used to evaluate the extent of virus spread in communities, our finding has important implications on the utility of existing serological diagnostic and surveillance for COVID-19.

Dynamics of viral shedding during ancestral or Omicron BA.1 SARS-CoV-2 infection and enhancement of pre-existing immunity during breakthrough infections

ABSTRACT Omicron variant is circulating in the presence of a globally acquired immunity unlike the ancestral SARS-CoV-2 isolate. Herein, we investigated the normalized viral load dynamics and viral culture status in 44 fully vaccinated healthcare workers (HCWs) infected with the Omicron BA.1 variant. Viral load dynamics of 38 unvaccinated HCWs infected with the 20A variant during the first pandemic wave was also studied. We then explored the impact of Omicron infection on pre-existing immunity assessing anti-RBD IgG levels, neutralizing antibody titres against 19A, Delta and Omicron isolates, as well as IFN-γ release following cell stimulation with SARS-CoV-2 peptides. We reported that two weeks after diagnosis a greater proportion of HCWs infected with 20A (78.9%, 15/19) than with Omicron BA.1 (44.7%, 17/38; p = 0.02) were still positive by RT-qPCR. We found that Omicron breakthrough infections led to an overall enhancement of vaccine-induced humoral and cellular immunity as soon as a median [interquartile range] of 8 [7–9] days post symptom onset. Among samples with similar high viral loads, non-culturable samples exhibited higher neutralizing antibody titres and anti-RBD IgG levels than culturable samples. Additionally, Omicron infection led to an enhancement of antibodies neutralization capacity against other SARS-CoV-2 isolates. Taken together, the results suggest that Omicron BA.1 vaccine breakthrough infection is associated with a faster viral clearance than that of the ancestral SARS-CoV-2, in addition this new variant leads to a rapid enhancement of the humoral response against multiple SARS-CoV-2 variants, and of the cellular response.

COVID-19 severity and vaccine breakthrough infections in idiopathic inflammatory myopathies, other systemic autoimmune and inflammatory diseases, and healthy controls: a multicenter cross-sectional study from the COVID-19 Vaccination in Autoimmune Diseases (COVAD) survey

ObjectivesWe aimed to compare the spectrum and severity of COVID-19 and vaccine breakthrough infections (BIs) among patients with IIMs, other systemic autoimmune and inflammatory diseases (SAIDs), and healthy controls (HCs).MethodsThis is a cross-sectional study with data from the COVAD study, a self-reported online global survey that collected demographics, COVID-19 history, and vaccination details from April to September 2021. Adult patients with at least one COVID-19 vaccine dose were included. BIs were defined as infections occurring > 2 weeks after any dose of vaccine. Characteristics associated with BI were analyzed with a multivariate regression analysis.ResultsAmong 10,900 respondents [42 (30–55) years, 74%-females, 45%-Caucasians] HCs were (47%), SAIDs (42%) and IIMs (11%). Patients with IIMs reported fewer COVID-19 cases before vaccination (6.2%-IIM vs 10.5%-SAIDs vs 14.6%-HC; OR = 0.6, 95% CI 0.4–0.8, and OR = 0.3, 95% CI 0.2–0.5, respectively). BIs were uncommon (1.4%-IIM; 1.9%-SAIDs; 3.2%-HC) and occurred in 17 IIM patients, 13 of whom were on immunosuppressants, and 3(18%) required hospitalization. All-cause hospitalization was higher in patients with IIM compared to HCs [23 (30%) vs 59 (8%), OR = 2.5, 95% CI 1.2–5.1 before vaccination, and 3 (18%) vs 9 (5%), OR = 2.6, 95% CI 1.3–5.3 in BI]. In a multivariate regression analysis, age 30–60 years was associated with a lower odds of BI (OR = 0.7, 95% CI 0.5–1.0), while the use of immunosuppressants had a higher odds of BI (OR = 1.6, 95% CI 1.1–2.7).ConclusionsPatients with IIMs reported fewer COVID-19 cases than HCs and other SAIDs, but had higher odds of all-cause hospitalization from COVID-19 than HCs. BIs were associated with the use of immunosuppressants and were uncommon in IIMs.

Longitudinal Severe Acute Respiratory Syndrome Coronavirus 2 Vaccine Antibody Responses and Identification of Vaccine Breakthrough Infections Among Healthcare Workers Using Nucleocapsid Immunoglobulin G.

Long-term studies of vaccine recipients are necessary to understand severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody durability and assess the impact of booster doses on antibody levels and protection from infection. The identification of vaccine breakthrough infections among fully vaccinated populations will be important in understanding vaccine efficacy and SARS-CoV-2 vaccine escape capacity. SARS-CoV-2 spike (S) receptor-binding domain and nucleocapsid (N) immunoglobulin (Ig) G levels were measured in a longitudinal study of 1000 Chicago healthcare workers who were infection naive or previously infected and then vaccinated. Changes in S and N IgG were followed up through 14 months, and vaccine breakthrough infections were identified by increasing levels of N IgG. SARS-CoV-2 S IgG antibody levels among previously infected and previously noninfected individuals decreased steadily for 11 months after vaccination. Administration of a booster 8-11 months after vaccination increased S IgG levels >2-fold beyond those observed after 2 doses, resulting in S IgG levels that were indistinguishable between previously infected and uninfected individuals. Increases in N IgG identified vaccine breakthrough infections and showed >15% breakthrough infection rates during the Omicron wave starting in December 2021. These results demonstrate SARS-CoV-2 antibody changes after vaccination and breakthrough infections and identify high levels of vaccine breakthrough infections during the Omicron wave, based on N IgG increases.

Molecular epidemiology of SARS-CoV-2 in healthcare workers and identification of viral genomic correlates of transmissibility and vaccine break through infection: A retrospective observational study from a cancer hospital in eastern India

PurposeDespite COVID vaccination with ChAdOx1 ncov-19 (COVISHIELD®) (ChAdOx1 ncov-19) a large number of healthcare workers (HCWs) were getting infected in wave-2 of the pandemic in a cancer hospital of India. It was important therefore to determine the genotypes responsible for vaccine breakthrough infections. Methods & ObjectivesRetrospective observational study of HCWs. Whole genome sequencing of SARS CoV-2 using Illumina NovaSeq was done. Mutations from both waves were compared to identify genomic correlates of transmissibility and vaccine breakthrough infections. ResultsVaccine breakthrough infections were seen in 127 HCWs out of 1806 fully vaccinated staff (7.03%). Median number of HCWs infected per day in wave-1 was 0.92 versus 3.25 in wave-2. Majority of wave-1 samples belonged to B.1 and B.1.1 lineage. Variant of concern- Delta variant (90%), and variant of interest- Kappa variant (10%), was seen in only wave-2 samples. Total mutation observed in wave-2 samples (median ​= ​44) was 1.8 times than wave-1 sample (median ​= ​24). Spike protein in wave-2 samples had 13 non-synonymous mutation as compared to 8 seen in wave-1 samples. E484Q-vaccine escape mutant was detected in five samples of wave-2; T478K – highly infectious mutation was seen in 31 samples of wave-2. We identified a novelcoding disruptive in-frame deletion (c.467_472delAGTTCA, p. Glu156_Arg158delinsGly) in the Spike protein. This mutation was seen only in wave-2 (78%, n ​= ​39) samples. ConclusionThe circulating virus strains in wave-2 infections demonstrated a greater degree of infectivity. There was a significant change in the genotypes observed in wave-1 and wave-2 infections along with almost twice the number of mutations. We noted that vaccine breakthrough infections (although mostly mild).

A comparative study of spike protein of SARS-CoV-2 and its variant Omicron (B.1.1.529) on some immune characteristics

The emergence of Omicron variant raises great concerns because of its rapid transmissibility and its numerous mutations in spike protein (S-protein). S-protein can act as a pathogen-associated molecular pattern and complement activator as well as antigen. We compared some immune characteristics of trimer S-proteins for wild type (WT-S) and B.1.1.529 Omicron (Omicron-S) to investigate whether the mutations have affected its pathogenicity and antigenic shift. The results indicated that WT-S and Omicron-S directly activated nuclear factor-κB (NF-κB) and induced the release of pro-inflammatory cytokines in macrophages, but the actions of Omicron-S were weaker. These inflammatory reactions could be abrogated by a Toll-like receptor 4 antagonist TAK-242. Two S-proteins failed to induce the production of antiviral molecular interferon-β. In contrast to pro-inflammatory effects, the ability of two S-proteins to activate complement was comparable. We also compared the binding ability of two S-proteins to a high-titer anti-WT-receptor-binding domain antibody. The data showed that WT-S strongly bound to this antibody, while Omicron-S was completely off-target. Collectively, the mutations of Omicron have a great impact on the pro-inflammatory ability and epitopes of S-protein, but little effect on its ability to activate complement. Addressing these issues can be helpful for more adequate understanding of the pathogenicity of Omicron and the vaccine breakthrough infection.

Vaccine breakthrough infection leads to distinct profiles of neutralizing antibody responses by SARS-CoV-2 variant.

Protective immunity against SARS-CoV-2 infection after COVID-19 vaccination may differ by variant. We enrolled vaccinated (n = 39) and unvaccinated (n = 11) individuals with acute, symptomatic SARS-CoV-2 Delta or Omicron infection and performed SARS-CoV-2 viral load quantification, whole-genome sequencing, and variant-specific antibody characterization at the time of acute illness and convalescence. Viral load at the time of infection was inversely correlated with antibody binding and neutralizing antibody responses. Across all variants tested, convalescent neutralization titers in unvaccinated individuals were markedly lower than in vaccinated individuals. Increases in antibody titers and neutralizing activity occurred at convalescence in a variant-specific manner. For example, among individuals infected with the Delta variant, neutralizing antibody responses were weakest against BA.2, whereas infection with Omicron BA.1 variant generated a broader response against all tested variants, including BA.2.

SEMI-QUANTITATIVE ANALYSIS OF SARS-COV-2 IGG ANTIBODIES FOLLOWING CHADOX1-NCOV (COVISHIELD™) VACCINATION

Objectives: The objectives of this study were semi-quantitatively analyze SARS-COV-2 IgG antibodies following covishield vaccination in healthcare workers and to follow-up them for 6 months for persistence of antibodies and for getting infected with SARS-COV-2. Methods: This was a prospective cohort study which was conducted at tertiary care hospital, South India. The blood samples were collected after second dose of vaccine at 28 days, 60 days, and 120 days. The serum was subjected for detection of IgG antibodies against S1 RBD (Receptor binding domain) of the spike protein antigen by Euroimmun kit (PerkinElmer company, Germany) using ELISA. Results: Out of 30 healthcare workers, 28 (93.3%) were seropositive and 2 (6.7%) were seronegative. Out of two seronegative, one participant acquired SARS-COV-2 infection with severe symptoms. There was approximately 50% reduction in antibody levels in almost all seropositive individuals after 3 months of second dose. Even after 6 months, 25 (83.3%) were seropositive, 2 (6.7%) were seronegative, and 3 (10%) were borderline. When the IgG antibody ratio levels of 28 days following second dose of vaccination were compared with levels after 6 months, which showed, p value of 0.024 which is &lt;0.05 implies statistically significant. Conclusion: Covishield vaccine induced good immune response in majority of the participants, the levels were sustainably positive until 6 months but decreasing pattern. The vaccine-induced antibodies prevented the severe symptoms among vaccine breakthrough infections.

SARS-CoV-2 Vaccine Breakthrough by Omicron and Delta Variants, New York, USA.

Recently emerged SARS-CoV-2 variants have greater potential than earlier variants to cause vaccine breakthrough infections. During emergence of the Delta and Omicron variants, a matched case–control analysis used a viral genomic sequence dataset linked with demographic and vaccination information from New York, USA, to examine associations between virus lineage and patient vaccination status, patient age, vaccine type, and time since vaccination. Case-patients were persons infected with the emerging virus lineage, and controls were persons infected with any other virus lineage. Infections in fully vaccinated and boosted persons were significantly associated with the Omicron lineage. Odds of infection with Omicron relative to Delta generally decreased with increasing patient age. A similar pattern was observed with vaccination status during Delta emergence but was not significant. Vaccines offered less protection against Omicron, thereby increasing the number of potential hosts for emerging variants.

S1232 COVID-19 Infection Post Liver Transplantation: A Closer Look at Vaccination Efficacy and Breakthrough Infection

S1232 COVID-19 Infection Post Liver Transplantation: A Closer Look at Vaccination Efficacy and Breakthrough Infection

Neutralizing Immunity Induced Against the Omicron BA.1 and BA.2 Variants in Vaccine Breakthrough Infections.

As of early 2022, the Omicron variants are the predominant circulating lineages globally. Understanding neutralizing antibody responses against Omicron BA.1 and BA.2 after vaccine breakthrough infections will provide insights into BA.2 infectivity and susceptibility to subsequent reinfection. Live virus neutralization assays were used to study immunity against Delta and Omicron BA.1 and BA.2 variants in samples from 86 individuals, 24 unvaccinated (27.9%) and 62 vaccinated (72.1%), who were infected with Delta (n = 42, 48.8%) or BA.1 (n = 44, 51.2%). Among the 62 vaccinated individuals, 39 were unboosted (62.9%), whereas 23 were boosted (37.1%). In unvaccinated infections, neutralizing antibodies (nAbs) against the three variants were weak or undetectable, except against Delta for Delta-infected individuals. Both Delta and BA.1 breakthrough infections resulted in strong nAb responses against ancestral wild-type and Delta lineages, but moderate nAb responses against BA.1 and BA.2, with similar titers between unboosted and boosted individuals. Antibody titers against BA.2 were generally higher than those against BA.1 in breakthrough infections. These results underscore the decreased immunogenicity of BA.1 compared to BA.2, insufficient neutralizing immunity against BA.2 in unvaccinated individuals, and moderate to strong neutralizing immunity induced against BA.2 in Delta and BA.1 breakthrough infections.

COVID 19 breakthrough infections in vaccinated dental student community of North Kerala- A survey based analysis

The ongoing global COVID-19 pandemic has infected hundreds of millions of people over the world, imposing a tremendous burden on the global healthcare system including the dental community. COVID-19 vaccines are currently the best defense against the rapidly evolving severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, there are emerging concerns about vaccine breakthrough infections. This study has been done to assess the COVID- 19 breakthrough infection among the vaccinated Dental student community of North Kerala and also evaluate and compare the severity of COVID-19 infection among vaccinated and non-vaccinated individuals. A survey was performed within the Dental student community which included BDS students, House surgeons and Post graduates by means of a questionnaire administered online via Google forms that consisted of demographic information and questions to assess severity of the COVID-19 breakthrough infection. The data were analyzed using the SPSS version 26 software. Result was presented in frequencies, percentages and charts showing the interrelatedness of the variables examined. Among the 714 respondents there were 11.9% males and 88.1% females. Majority of the study subjects reported to have completed two doses of Covid vaccine, while 11.5% had taken only a single dose and 1% had not been vaccinated at all. Around 13% of subjects gave history of being Covid positive before vaccination and (14.7%) got infected even after vaccination.New Covid variants are being evolved continuously, thereby increasing the chance for transmissibility and evasion of the host immune response. This could be the reason for the 14.7% breakthrough infections reported in our study. Therefore, the need for future studies to recognize factors leading to inadequate vaccine response in those with breakthrough infections and ways to mitigate them is highlighted.

Vaccine breakthrough infections with SARS-CoV-2: Why older adults need booster vaccinations

ObjectivesCOVID-19 vaccinations are highly efficacious in preventing severe illness that can lead to hospitalizations and death, but incidents of vaccine breakthrough (VBT) infections persist. We examined VBT infections within a congregate setting to help guide public health practices. Study designThis is a retrospective cohort study of VBT infections identified via polymerase chain reaction (PCR) testing between 2/1/2021-11/1/2021. MethodsA VBT infection was defined as the detection of SARS-CoV-2 collected from a person ≥14 days after all recommended doses of a COVID-19 vaccine. VBT infections were examined in five California psychiatric inpatient hospitals with a workforce of more than 10,000 hospital staff and approximately 5500 patients. Results415 VBT infections out of 14,101 fully vaccinated individuals within our system (2.9%) were identified. Days since final vaccine date ranged from 16 to 291 days. Kruskal-Wallis nonparametric test revealed a statistically significant difference in age between individuals with VBT infections versus all other vaccinated individuals [U = 6.47, p = .01]. A chi-square test of independence revealed no significant sex differences between individuals with VBT infections (58.8% male and 41.2% female) versus all other vaccinated individuals (59.6% male and 40.4% female; X2 (3, N = 14101) = 5.059, p = .167). Out of 415 VBT cases, 65.1% received the Moderna vaccine, 33.2% received Pfizer, and 1.7% received J&J; and 38.1% were asymptomatic at time of VBT infection, 24.1% were symptomatic, while 37.8% were missing symptom data. ConclusionsVaccination campaigns, including boosters and continued surveillance, are important complimentary strategies for reducing the proliferation of COVID-19 VBT cases and severity of symptoms associated with COVID-19.

Serological Response and Clinical Protection of Anti-SARS-CoV-2 Vaccination and the Role of Immunosuppressive Drugs in a Cohort of Kidney Transplant Patients.

Vaccination against SARS-CoV2 represents a key weapon to prevent COVID-19, but lower response rates to vaccination have frequently been reported in solid organ transplant recipients. The aim of our study was to evaluate the rate of seroconversion to SARS-CoV-2 mRNA vaccines in a cohort of kidney transplant recipients and the potential role of the different immunosuppressive regimens. We conducted an observational retrospective cohort study in kidney transplant patients vaccinated for COVID-19. For each patient, we evaluated IgG anti-S-RBD SARS-CoV-2 titers immediately before the administration of first COVID-19 vaccination dose, 20 days after the first dose and 40 days after the second dose. Moreover, we evaluated the type of immunosuppressive treatment and the incidence of vaccine breakthrough SARS-CoV-2 infection. We enrolled 121 kidney transplant patients vaccinated for COVID-19. At the time of administration of the first vaccine dose, all patients had a negative antibody titer; only 4.1% had positive antibody titers 20 days after the first dose. More than half patients 62 (51%) had protective antibody titers 40 days after the second dose. A total of 18 Solid Organ Transplant Recipients (SOTRs) (14.9%) got a SARS-CoV-2 breakthrough infection during the study period. With regard to immunosuppressive regimen, patients on mycophenolate-based regimen (48.7%) showed the lowest antibody response rates (27.5%) compared to other regimens. Our study confirms that kidney transplant patients show a poor response to two doses of COVID-19 vaccination. Moreover, in our study the use of mycophenolate is significantly associated with a non-response to COVID-19 m-RNA vaccines.

A comparison between SARS-CoV-1 and SARS-CoV2: an update on current COVID-19 vaccines.

Since the outbreak of the novel coronavirus disease 2019 (COVID-19) in Wuhan, China, many health care systems have been heavily engaged in treating and preventing the disease, and the year 2020 may be called as “historic COVID-19 vaccine breakthrough”. Due to the COVID-19 pandemic, many companies have initiated investigations on developing an efficient and safe vaccine against the virus. From Moderna and Pfizer in the United States to PastocoVac in Pasteur Institute of Iran and the University of Oxford in the United Kingdom, different candidates have been introduced to the market. COVID-19 vaccine research has been facilitated based on genome and structural information, bioinformatics predictions, epitope mapping, and data obtained from the previous developments of severe acute respiratory syndrome coronavirus (SARS-CoV or SARS-CoV-1) and middle east respiratory syndrome coronavirus (MERS-CoV) vaccine candidates. SARS-CoV genome sequence is highly homologous to the one in COVID-19 and both viruses use the same receptor, angiotensin-converting enzyme 2 (ACE2). Moreover, the immune system responds to these viruses, partially in the same way. Considering the on-going COVID-19 pandemic and previous attempts to manufacture SARS-CoV vaccines, this paper is going to discuss clinical cases as well as vaccine challenges, including those related to infrastructures, transportation, possible adverse reactions, utilized delivery systems (e.g., nanotechnology and electroporation) and probable vaccine-induced mutations.Graphical abstract