Effects of Second Dose of SARS-CoV-2 Vaccination on Household Transmission, England.

A single SARS-CoV-2 vaccine dose reduces onward transmission from case-patients. We assessed the potential effects of receiving 2 doses on household transmission for case-patients in England and their household contacts. We used stratified Cox regression models to calculate hazard ratios (HRs) for contacts becoming secondary case-patients, comparing contacts of 2-dose vaccinated and unvaccinated index case-patients. We controlled for age, sex, and vaccination status of case-patients and contacts, as well as region, household composition, and relative socioeconomic condition based on household location. During the Alpha-dominant period, HRs were 0.19 (0.13-0.28) for contacts of 2-dose BNT162b2-vaccinated case-patients and 0.54 (0.41-0.69) for contacts of 2-dose Ch4dOx1-vaccinated case-patients; during the Delta-dominant period, HRs were higher, 0.74 (0.72-0.76) for BNT162b2 and 1.06 (1.04-1.08) for Ch4dOx1. Reduction of onward transmission was lower for index case-patients who tested positive ≥2 months after the second dose of either vaccine.

Adverse Effects Following the First and Second Dose in Individuals Receiving the Pfizer/BioNTech COVID-19 Vaccine: A Cohort Study

The FDA-approved vaccine against the novel coronavirus developed by Pfizer and BioNTech became widely popular in Iraq. The study aims to evaluate the incidence of vaccine adverse reactions, and severity after first and second doses and to link some of the demographic criteria of recipients. This study included 850 adults (16 years and older), and the sample was collected from a randomly selected vaccination center in Baghdad, Iraq for the period January to March 2022. Study Participants were directly interviewed while taking the first dose. Later on, phone calls were used to monitor participants' self-reported local or systemic adverse reactions for one week after the first dose and second dose. The participants' age range was (19-76 years) with a mean of (46.2 ± 15.8) years. 59.9% were males. The mean body mass index (BMI) was (27.7 ±2.9). The incidence of vaccine adverse reactions after first and second doses were: first dose (local 17%, systemic 27%), second dose (local 27%, systemic 35%). Ordinal logistic regression analysis after adjusting for age, sex, and past medical history (PMHx) showed a higher incidence and severity in females and those with PMHx in nearly all the types of reactions except for chills (second dose) and PMHx (two doses), muscle or joint pain (two doses). Spearman's Rank test showed an insignificant correlation with any type of reaction. The vaccine is generally safe and adverse reactions are mild and tolerable in the majority of cases. ©2022 by authors, all rights reserved.

Recombinant zoster vaccine (RZV) second-dose series completion in adults aged 50-64 years in the United States.

In 2018, CDC recommended a highly efficacious adjuvanted recombinant zoster vaccine (RZV) as a 2-dose series for prevention of herpes zoster (HZ) for immunocompetent persons age ≥ 50 years, with the 2nd dose recommended 2-6 months after the 1st dose. We estimated second-dose RZV series completion in the U.S. among 50-64-year-olds using two administrative databases. Second-dose RZV series completion was ∼70% within 6-months and 80% within 12-months of first dose. Among those who received only 1 RZV dose with at least 12 months of follow-up time, 96% had a missed opportunity for a second-dose vaccination, defined as a provider or pharmacy visit, among whom 36% had a visit for influenza or pneumococcal vaccination within 2-12 months of their first-dose of RZV. We found that RZV series completion rates in 50-64-year-olds was high. Availability of RZV at pharmacies has potentially helped increase series completion, but missed opportunities remain.

ADVERSE EVENTS FOLLOWING IMMUNIZATION ASSOCIATED WITH COVID VACCINES AMONG HEALTHCARE WORKERS IN TERTIARY CARE CENTRE IN A DISTRICT

INTRODUCTION: Myths regarding AEFI associated with covid vaccines caused fear among general population to take up vaccination against covid. OBJECTIVES: 1. To study the socio-demographic factors associated with AEFI following COVID vaccination among healthcare workers. 2. To study the AEFI following covid vaccination. MATERIALS AND METHODS: The study is a cross-sectional study with minimum sample size of 178 and the study was done on 377 healthcare workers using simple random sampling method. Data was collected using pre-structured questionnaire and analyzed using proportions, bar charts & chi-square test of significance. RESULTS: AEFI after first dose and second dose was highest among 21-30 years age group and least among 61-70 yrs age group and below 20 years. AEFI reporting was highest in females compared to males both after first dose and second dose. AEFI after first dose was highest among nursing staff followed by doctors whereas after second dose it was vice-versa. Fever and body pains were the most common adverse events after first dose (within 1-5 days) whereas after second dose, pain at the site of injection and body pains were more common. CONCLUSION: Majority of the adverse events reported after covid vaccination in the study were only minor not needing any hospitalization. [ FROM AUTHOR]

Healthcare Worker Study Cohort to Determine the Level and Durability of Cellular and Humoral Immune Responses after Two Doses of SARS-CoV-2 Vaccination.

We prospectively studied immunological response against SARS-CoV-2 after vaccination among healthcare workers without (group A) and with previous infection (group B). The analyses were collected at T0 (before the BNT162b2), T1 (before the second dose), T2 and T6 (1 and 6 months after the second dose). For cellular immune response, the activation-induced cell marker assay was performed with CD4 and CD8 Spike peptide megapools expressed as Stimulation Index. For humoral immune response, we determined antibodies to Spike-1 and nucleocapsid protein. The linear mixed model compared specific times to T0. The CD4+ Spike response overall rate of change was significant at T1 (p = 0.038) and at T2 (p < 0.001), while decreasing at T6. For CD8+ Spike reactivity, the interaction between the time and group was significant (p = 0.0265), and the p value for group comparison was significant at the baseline (p = 0.0030) with higher SI in previously infected subjects. Overall, the anti-S Abs significantly increased from T1 to T6 compared to T0. The group B at T6 retained high anti-S titer (p < 0.001). At T6, in both groups we found a persistent humoral response and a high CD4+ T cell response able to cross recognize SARS-COV-2 variants including epsilon, even if not a circulating virus at that time.

A study on seroconversion following first & second doses of ChAdOx1 nCoV-19 vaccine in Central Kerala.

Background & objectives: Vaccination against COVID-19 induces spike protein-binding IgG antibodies, a robust correlate of protection against COVID-19. This study was undertaken to assess the humoral response after completion of both the doses of ChAdOx1 nCoV vaccine in healthcare workers (HCWs) at a tertiary care health centre in India. Methods: A cross-sectional COVID-19 vaccine-induced antibody study was conducted among HCWs. IgG antibodies against spike protein were measured at least 28 days after the first dose and the second dose of vaccination in both SARS CoV-2 naïve and recovered HCWs. Mean and median antibody titre following each dose of vaccine and its association with age, gender, co-morbidities and factors such as exercise, stress and sleep deprivation were also explored. Results: Among the 200 vaccine recipients, 91.5 per cent showed seroconversion after the first dose and 99.5 per cent after the second dose. The mean titre after the second dose was significantly higher when compared to the first dose (12.68±4.17 vs. 9.83±6.3, P=0.001). More than half (54%) had high antibody titre ≥12 S/Co (Signal/cut-off). Previous COVID-19 infection was the single most important factor influencing antibody production, where the mean titre just after a single dose [mean-17.81±5.94, median-20.5 (interquartile range [IQR]-3.7)] surpassed the titre after the second dose in SARS CoV-2 naïve individuals [mean-12.29±4.00, median-12.8 (IQR-3.7), P=0.001]. Furthermore, 28 per cent of vaccinees showed a reduction in titre after the second dose. The mean fall in titre was 2.25±1.40 and was more pronounced in males, the younger age group and those with previous COVID-19 infection. Interpretation & conclusions: ChAdOx1 nCov-19 vaccine after two doses elicited an excellent immune response. However, greater immunogenicity after the first dose was seen among those with previous COVID-19 infection, even surpassing the titre achieved by the second dose of vaccine in SARS CoV-2 naïve recipients. A fall in antibody titre after the second dose is a matter of concern and requires further studies.

The Adverse Reactions of Pfizer BioNTech COVID-19 Vaccine Booster Dose are Mild and Similar to the Second Dose Responses: A Retrospective Cross-Sectional Study.

Background: Like other vaccines, Pfizer BioNTech's COVID-19 vaccine efficacy against SARS-CoV-2 virus infections begins to decline within a few months after the 2nd dose. On August 12, 2021, the FDA allowed additional Pfizer BioNTch's COVID-19 vaccine dose (3rd or booster dose) for individuals with weakened immunity. This study aimed to evaluate the short-term adverse reactions (ADRs) of the 2nd and the 3rd doses of the Pfizer BioNTech COVID-19 vaccine. Methods: Information for this study was collected by Google Form questionnaire (online survey). The results included responses from 442 people, the majority from Saudi Arabia. Results: The most common local ADRs following the 3rd dose were injection site pain, injection site hypersensitivity, and axillary lymph node swelling. The most common systemic ADRs were fatigue, muscle pain, bone pain, headache, and fever less than 38ºC. Less common systemic ADRs were shivering, fever more than 38ºC, nasal congestion and rhinorrhea, arrhythmia, cough, abdominal pain, chest tightness, nausea, diarrhea, vomiting, and tachypnea. Rare systemic ADRs were constipation, dizziness and vertigo, lack of concentration, sore throat, excessive hair loss, dysmenorrhea and heavy menstruation, and Bell's palsy. Severe allergic reactions were reported by 2.6% of participants after the 2nd dose, compared with none after the 3rd dose. Nasal congestion and runny nose are more frequent after the 3rd dose. The ADRs of the 2nd and 3rd doses were significantly more prevalent in females. 12% of participants reported ADRs lasting more than one week after the 3rd dose compared to 5% after the 2nd dose. People ≤ 60 years were more affected by the vaccine ADRs. Conclusion: Most of the ADRs reported after the 3rd vaccine dose were consistent with the Pfizer vaccine information sheet and similar to the 2nd dose ADRs.

Association between Adverse Reactions to the First and Second Doses of COVID-19 Vaccine.

This study investigated the frequency of adverse reactions to COVID-19 vaccines in Japan and the impact of first-dose adverse reactions on second-dose adverse reactions. Individuals who received an mRNA COVID-19 vaccine at our center in March or April 2021 were included. Data were collected using questionnaires. The main factors were age (<40, 40-59, and >60 years), sex, underlying disease, and first-dose adverse reaction. The primary outcomes were incidence of local and systemic adverse reactions (ARs) attributable to the vaccine. Logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Among 671 participants, 90% experienced local or systemic ARs. An AR to the first dose was associated with a significantly increased risk of an AR to the second dose (OR: 49.63, 95% CI: 21.96-112.16). ARs were less common among men than among women (OR: 0.36, 95% CI: 0.17-0.76). Local ARs were less common among those aged 60 years or older (OR: 0.35, 95% CI: 0.18-0.66), whereas systemic ARs were more common among those aged under 40 years. Information on ARs to the first dose is important for healthcare providers and recipients when making vaccination decisions.

Modeling waning and boosting of COVID-19 in Canada with vaccination.

SARS-CoV-2, the causative agent of COVID-19, has caused devastating health and economic impacts around the globe since its appearance in late 2019. The advent of effective vaccines leads to open questions on how best to vaccinate the population. To address such questions, we developed a model of COVID-19 infection by age that includes the waning and boosting of immunity against SARS-CoV-2 in the context of infection and vaccination. The model also accounts for changes to infectivity of the virus, such as public health mitigation protocols over time, increases in the transmissibility of variants of concern, changes in compliance to mask wearing and social distancing, and changes in testing rates. The model is employed to study public health mitigation and vaccination of the COVID-19 epidemic in Canada, including different vaccination programs (rollout by age), and delays between doses in a two-dose vaccine. We find that the decision to delay the second dose of vaccine is appropriate in the Canadian context. We also find that the benefits of a COVID-19 vaccination program in terms of reductions in infections is increased if vaccination of 15-19 year olds are included in the vaccine rollout.

A cohort analysis of SARS-CoV-2 anti-spike protein receptor binding domain (RBD) IgG levels and neutralizing antibodies in fully vaccinated healthcare workers.

OBJECTIVES: The waning of humoral immunity after COVID-19 vaccine booster (third dose) has not yet been fully evaluated. This study updates data on anti-SARS-CoV-2 spike protein receptor binding domain (S-RBD) binding antibodies (bAb) and neutralizing antibodies (NAb) levels in individuals with homologous vaccination 3-4 months after receiving the booster dose. METHODS: Fifty-five healthcare workers (HCW) from Padova University-Hospital were asked to collect serum samples for determining antibodies (Ab) at 12 (t12) and 28 (t28) days, at 6 months (t6m) after their first Comirnaty/BNT162b2 inoculation, and 3-4 months after receiving the 3rd homologous booster dose. HCW were monitored weekly for SARS-CoV-2 infection. Ab titers were measured by two chemiluminescent immunoassays, one targeting the S-RBD immunoglobulin G (IgG), and one surrogate viral neutralization test (sVNT), measuring NAb. RESULTS: Twenty of the HCW had natural COVID-19 infection (COVID+) at different times, before either the first or the second vaccination. Median S-RBD IgG and NAb levels and their interquartile ranges 3-4 months after the 3rd dose were 1,076 (529-3,409) kBAU/L and 15.8 (11.3-38.3) mg/L, respectively, for COVID-, and 1,373 (700-1,373) kBAU/L and 21 (12.8-53.9) mg/L, respectively, for COVID+. At multivariate regression analyses, with age and gender included as covariates, S-RBD IgG bAb and sVNT NAb levels were closely associated with the time interval between serological determination and the 3rd vaccine dose (log10 ßcoeff=-0.013, p=0.012 and log10 ßcoeff=-0.010, p=0.025) for COVID+, whereas no such association was found in COVID- individuals. CONCLUSIONS: The third booster dose increases anti-SARS-CoV-2 Ab levels, elevated levels persisting for up to 3-4 months. Waning of Ab levels appears to be less pronounced for COVID+ individuals.

Post-vaccination side effects following the second dose of COVID-19 vaccine among health care workers

The coronavirus disease 2019 (COVID-19) vaccines were launched after granting them ‘emergency use authorization’ approval. Beyond the clinical trial, there was very limited data on the side effects following vaccination This is a longitudinal study among health care workers (HCWs) in a tertiary care hospital. Information was also collected using a pre-tested semi-structured questionnaire which included their demographic details, first dose and second dose. Post-vaccination follow-up was done at the centre which was then followed up by telephonic monitoring after 48 hours. In the present study 1,034 (65.6%) health care workers (HCWs) did not report any serious reactions/symptoms. Pain and tenderness were the most commonly reported side-effects in more than half. The severity of the symptoms following the second dose of vaccine was compared with the first dose and it was found that the majority 653 (41.4%) had reported no symptoms/reactions following both doses of vaccine. Every vaccine will have some side effects but it is important to understand that in the ongoing pandemic, vaccines are our “best shot” to fight against this virus. © 2022, Intelektual Pustaka Media Utama. All rights reserved.

Immune Responses to the ChAdOx1 nCoV-19 and BNT162b2 Vaccines and to Natural Coronavirus Disease 2019 Infections Over a 3-Month Period.

BACKGROUND: There are limited data directly comparing immune responses to vaccines and to natural infections with coronavirus disease 2019 (COVID-19). This study assessed the immunogenicity of the BNT162b2 and ChAdOx1 nCoV-19 vaccines over a 3-month period and compared the immune responses with those to natural infections. METHOD: We enrolled healthcare workers who received BNT162b2 or ChAdOx1 nCoV-19 vaccines and patients with confirmed COVID-19 and then measured S1 immunoglobulin (Ig) G and neutralizing antibodies and T-cell responses. RESULTS: A total of 121 vaccinees and 26 patients with confirmed COVID-19 were analyzed. After the second dose, the BNT162b2 vaccine yielded S1 IgG antibody responses similar to those achieved with natural infections (mean IgG titer [standard deviation], 2241 [899] vs 2601 [5039]; P = .68) but significantly stronger than responses to the ChAdOx1 vaccine (174 [96]; P < .001). The neutralizing antibody titer generated by BNT162b2 was 6-fold higher than that generated by ChAdOx1 but lower than that by natural infection. T-cell responses persisted for 3 months with BNT162b2 and natural infection but decreased with ChAdOx1. CONCLUSIONS: Antibody responses after the second dose of BNT162b2 are higher than after the second dose of ChAdOx1 and like those occurring after natural infection. T-cell responses are maintained longer in BNT162b2 vaccinees than in ChAdOx1 vaccinees.

Knowledge and attitude toward the second round of COVID-19 vaccines among teachers working at southern public universities in Ethiopia.

About 1.9 million people in Ethiopia have received a first dose of COVID-19 vaccine, which are given to frontline health care workers and university instructors through a campaign. After healthcare workers, teachers at all levels in Ethiopia are assumed to be at a higher risk of exposure to COVID-19. An institution-based cross-sectional study design was used. Simple random sampling was used to select participants. Data were collected using a structured, self-administered questionnaire. Logistic regression analysis was conducted for all variables, and a p-value < 0.05 at 95% CI was considered statistically significant. Overall, 60.8% and 79.7% of participants had good knowledge of and positive attitudes toward a second round of COVID-19 vaccines, respectively. Age (AOR = 1.51 [95% CI = 1.003-3.63]), profession (AOR = 1.402 [95% CI = 1.107-3.003]), work experience (AOR = 1.509 [95% CI = 1.151-2.283]), and chronic diseases (AOR = 2.142 [95% CI = 1.337-3.092]) were predictor variables for knowledge about the second round of COVID-19 vaccines. Sex (AOR = 1.386 [95% CI = 1.018-2.763]), marital status (AOR = 4.180 [95% CI = 2.397-6.989]), profession (AOR = 1.102 [95% CI = 1.008-3.123]), work experience (AOR = 1.211 [95% CI = 1.029-2.877]), and chronic diseases (AOR = 6.110 [95% CI = 4.892-10.661]) were predictor variables for attitudes toward a second round of COVID-19 vaccines. Generally, knowledge and attitudes toward the second round of COVID-19 vaccines among instructors were low. Thus, health education and communication are very crucial.

Active Surveillance of Adverse Events in Healthcare Workers Recipients After Vaccination with COVID-19 BNT162b2 Vaccine (Pfizer-BioNTech, Comirnaty): A Cross-Sectional Study.

In this cross-sectional study, adverse events after the first and second dose of BNT162b2 mRNA (Pfizer-BioNTech, Comirnaty) vaccine against coronavirus disease 2019 were investigated among employees of clinics in central Italy. A 42-items questionnaire was administrated to vaccine recipients. Adverse events were classified based on severity and occurrence as reported in the literature. A descriptive/univariate analysis using Chi-square or Fisher's Exact tests was performed. Odds ratio (OR) and 95% confidence intervals were calculated to assess risk factors. 340 individuals (61.5% females; median age 49 years) participated. Adverse events were reported by 279 (82%) and 281 (82.6%) individuals as induced by the first and second dose, respectively. Mild reactions were mainly reported (80.9% and 80.3%), followed by moderate (11.8% and 37.1%) and severe (3.8% and 4.7%). Adverse events were identical to those already described as very common (81.8% and 80.6%), although vaccine-coincidental events not cited in the literature were reported by 6% and 15.6% following each dose. Age ≤ 55 years was a risk factor for any adverse event after each injection (ORs: 2.942 and 2.818), as well as female sex for those mild (ORs: 1.856 and 2.818) and common (ORs: 3.452 and 2.145). Findings were consistent with national reports as most of the adverse events were mild and associated with female sex and young age, while investigations are needed for reactions not described elsewhere. Data are useful to support the vaccine safety profile, also because largely targeted healthcare personnel more skilled than general population in self-diagnosis of health-related issues.