A Systematic Review on COVID-19 Vaccine Strategies, Their Effectiveness, and Issues

Immunogenicity and Protectivity of Sputnik V Vaccine in hACE2-Transgenic Mice against Homologous and Heterologous SARS-CoV-2 Lineages Including Far-Distanced Omicron BA.5

BACKGROUND

The SARS-CoV-2 virus continuously acquires mutations, leading to the emergence of new variants. Notably, the effectiveness of global vaccination efforts has significantly declined with the rise and spread of the B.1.1.529 (Omicron) variant.

METHODS

The study used virological, immunological and histological research methods, as well as methods of working with laboratory animals. In this study, we evaluated the Gam-COVID-Vac (Sputnik V), an adenoviral vaccine developed by the N.F. Gamaleya National Research Center for Epidemiology and Microbiology, and conducted experiments on hemizygous K18-ACE2-transgenic F1 mice. The variants studied included B.1.1.1, B.1.1.7, B.1.351, B.1.1.28/P.1, B.1.617.2, and B.1.1.529 BA.5.

RESULTS

Our findings demonstrate that the Sputnik V vaccine elicits a robust humoral and cellular immune response, effectively protecting vaccinated animals from challenges posed by various SARS-CoV-2 variants. However, we observed a notable reduction in vaccine efficacy against the B.1.1.529 (Omicron BA.5) variant.

CONCLUSIONS

Our results indicate that ongoing monitoring of emerging mutations is crucial to assess vaccine efficacy against new SARS-CoV-2 variants to identify those with pandemic potential. If protective efficacy declines, it will be imperative to develop new vaccines tailored to current variants of the virus.

Prevalence of nephropathy among diabetic patients in North American region: A systematic review and meta-analysis

BACKGROUND

Nephropathy is one of the most common microvascular impediments of diabetes mellitus. In this study, we aimed to estimate the prevalence of nephropathy in diabetic patients across the North American region.

METHODS

Eligible studies were screened out from 3 electronic databases, for example, PubMed, Google Scholar, and ScienceDirect using specific search keywords based on the eligibility criteria. Extracting the data from the included studies publication bias, quality assessment, outlier investigation, and meta-analysis was done followed by the subgroup analysis. A total of 11 studies met the study inclusion criteria. Meta-analysis was performed with the extracted data.

RESULTS

Pooled prevalence of 28.2% (95% confidence interval [CI]: 19.7-36.7) with a high rate of heterogeneity (I2 = 100%) was identified. The pooled prevalence of nephropathy among diabetic patients in the United States of America, Canada, and Mexico was 24.2% (95% CI: 13.8-34.5), 31.2% (95% CI: 25.8-36.5), and 31.1% (95% CI: 20.8-41.5), respectively.

CONCLUSION

The prevalence of nephropathy among diabetic patients was found lower in the United States of America as compared to Canada and Mexico. Besides, the pooled prevalence of the North American region was found to be lower as compared to the African, European, and Asian regions. Minimizing the pathogenic factors, sufficient diagnostic, healthcare facilities, and awareness are recommended to improve the situation.

Comparison of long-term anti-RBD SARS-CoV-2 antibody response following different vaccination schemes in Tunisia

AIM

The study aimed to compare long-term vaccine-induced humoral immunity following different vaccines regimens.

METHODS

Anti-S-RBD total antibody levels were measured in blood samples of 167 participants nearly 6 months post-vaccination. Participants had received one; two or four doses of Pfizer vaccine or who received a third dose of mRNA vaccine (Pfizer) and primed with mRNA (Pfizer/Moderna), adenoviral (AstraZeneca/Jonson & Jonson) or inactivated (CoronaVac/Sinopharm) vaccine.

RESULTS

Among all vaccination regimens, fourth dose of Pfizer achieved the highest S-RBD antibody titers. Nevertheless, the third dose of mRNA vaccine primed with adenoviral vaccine achieved the lowest titers of S-RBD antibody. Notably, the group that received a third dose of mRNA primed with two doses of mRNA vaccine exhibited higher S-RBD antibody compared to groups inoculated with a third dose of mRNA and primed with inactivated or adenovirus vaccine.

CONCLUSION

Our data showed the superiority of three mRNA vaccinations compared to third heterologous vaccine (inactivated of adenoviral) including mRNA as booster in terms of humoral immunogenicity. Our findings supporting the use of additional booster shot from a more potent vaccine type such as mRNA vaccines. Nevertheless, due to the limited number of subjects, it is difficult to extrapolate the results of our study to the whole of Tunisian population. Future studies should investigate a larger cohort and other potential correlates of protection, such as cellular immunity and how it is affected by different vaccination schemes after long-term post-vaccination.

Tailoring COVID-19 Vaccination Strategies in High-Seroprevalence Settings: Insights from Ethiopia

This study aimed to retrospectively assess the cost-effectiveness of various COVID-19 vaccination strategies in Ethiopia. It involved healthcare workers (HCWs) and community participants; and was conducted through interviews and serological tests. Local SARS-CoV-2 variants and seroprevalence rates, as well as national COVID-19 reports and vaccination status were also analyzed. A cost-effectiveness analysis was performed to determine the most economical vaccination strategies in settings with limited vaccine access and high SARS-CoV-2 seroprevalence. Before the arrival of the vaccines, 65% of HCWs had antibodies against SARS-CoV-2, indicating prior exposure to the virus. Individuals with prior infection exhibited a greater antibody response to COVID-19 vaccines and experienced fewer new infections compared to those without prior infection, regardless of vaccination status (5% vs. 24%, p < 0.001 for vaccinated; 3% vs. 48%, p < 0.001 for unvaccinated). The cost-effectiveness analysis indicated that a single-dose vaccination strategy is optimal in settings with high underlying seroprevalence and limited vaccine availability. This study underscores the need for pragmatic vaccination strategies tailored to local contexts, particularly in high-seroprevalence regions, to maximize vaccine impact and minimize the spread of COVID-19. Implementing a targeted approach based on local seroprevalence information could have helped Ethiopia achieve higher vaccination rates and prevent subsequent outbreaks.

Insight into COVID-19 associated liver injury: Mechanisms, evaluation, and clinical implications

COVID-19 has affected millions worldwide, causing significant morbidity and mortality. While predominantly involving the respiratory tract, SARS-CoV-2 has also caused systemic illnesses involving other sites. Liver injury due to COVID-19 has been variably reported in observational studies. It has been postulated that liver damage may be due to direct damage by the SARS-CoV-2 virus or multifactorial secondary to hepatotoxic therapeutic options, as well as cytokine release syndrome and sepsis-induced multiorgan dysfunction. The approach to a COVID-19 patient with liver injury requires a thorough evaluation of the pattern of hepatocellular injury, along with the presence of underlying chronic liver disease and concurrent medications which may cause drug-induced liver injury. While studies have shown uneventful recovery in the majority of mildly affected patients, severe COVID-19 associated liver injury has been associated with higher mortality, prolonged hospitalization, and greater morbidity in survivors. Furthermore, its impact on long-term outcomes remains to be ascertained as recent studies report an association with metabolic-fatty liver disease. This present review provides insight into the subject by describing the postulated mechanism of liver injury, its impact in the presence of pre-existing liver disease, and its short- and long-term clinical implications.

Safety monitoring of precautionary third dose of COVID-19 vaccines in a district in Northern India

Background

The World Health Organization (WHO) declared Coronavirus disease-19 (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) a pandemic on March 11, 2020. On 16th January 2021, India began its vaccination programme using two COVID-19 vaccines (Covishield and Covaxin). Precautionary dose (booster shots) was administered to health and front-line workers in the beginning and then to all eligible populations.

Material and Methods

This was a descriptive observational study conducted in the COVID-19 vaccination centres of Karnal district and the ADR monitoring centre, KCGMC, Karnal. During the visits to vaccination centres, all beneficiaries of the precautionary third dose of COVID-19 vaccines as well as healthcare workers were sensitized to report in case of any adverse event following vaccination as part of the policy of the vaccination programme run by the government and Pharmacovigilance Programme of India. The data were collected in suspected adverse drug reaction (ADR) reporting form version 1.4, and causality assessment was done as per the WHO-UMC scale. The data were analysed as simple proportions and percentages.

Results

The booster dose was administered to 72,853 individuals, while the 1st dose and 2nd dose were given to 13,30,042 and 10,73,050, respectively. Only three ADRs were reported with the booster dose in 34 vaccination centres in the Karnal district. These three ADRs were classified as unlikely on causality assessment and hence not included in the analysis.

Conclusion

The booster dose administered for the prevention of COVID-19 has been found to be reasonably safe. The population who received COVID-19 booster doses was significantly less than the populations who received the first and second doses, which suggests a low acceptance rate.

Antibody Response after Homologous and Heterologous Prime-Boost COVID-19 Vaccination in a Bangladeshi Residential University Cohort

COVID-19 vaccination strategies, including heterologous prime-boost regimens and additional booster doses, aim to optimize immune responses. However, seroepidemiological studies on immune responses to different COVID-19 vaccine types and schedules remain limited. This study investigated antibody levels following homologous and heterologous prime-and-boost COVID-19 vaccination in Bangladesh. In a cohort of 606 participants who received first/second/booster doses of vaccines (AstraZeneca, Moderna, Pfizer-BioNTech, and Sinopharm), anti-spike IgG and anti-nucleocapsid IgG levels were measured. Antibody titer variations with respect to age, gender, intervals between doses, and prior infection status were analyzed. mRNA vaccines elicited the highest antibody levels after homologous and heterologous boosting. The AstraZeneca booster resulted in a sharp titer decline rate of ~0.04 units per day. Second or booster vaccine doses significantly increased antibody levels, especially in males (p < 0.05). Older age correlated with higher titers, likely reflecting previous infection, which was further confirmed by the elevation of anti-nucleocapsid IgG levels. About 95.5% of non-Sinopharm recipients were anti-nucleocapsid IgG positive, suggesting prior exposure exceeding self-reported infections (12.5%). mRNA and heterologous COVID-19 boosting enhances humoral immunity over homologous prime-boost vector/inactivated vaccination. However, waning immunity merits further investigation across vaccine platforms.

Effect of inactivated vaccine boosters against severe and critical COVID-19 during the Omicron BA.5 wave: A retrospective analysis of hospitalized patients in China

Few real-world analyses of the ability of vaccines to protect against severe COVID-19 have been published. In this real-world study, we compared the prevalence of severe or critical COVID-19 between patients at our hospital who were not vaccinated against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or who had been vaccinated partial, full, or booster course with the CoronaVac, containing inactivated virus propagated in Vero cells. Data from electronic health records were retrospectively analyzed for 4090 inpatients with COVID-19 who were treated at West China Hospital, Chengdu between December 6, 2022 and February 14, 2023. Clinicodemographic characteristics and COVID-19 severity were compared among patients who had been vaccinated 0, 1, 2 or more times with inactivated vaccine CoronaVac. To evaluate vaccine effectiveness over time, we plotted Kaplan-Meier curves with the percentage of patients with the outcome of severe or critical COVID-19 from the time of their last vaccine dose according to vaccination status. Ordinal logistic regression was used to assess associations between vaccination status and COVID-19 severity. Cox regression was used to identify risk factors for severe or critical COVID-19. Among the 4090 patients, 171 had been vaccinated partial and 423 twice with the full CoronaVac regimens, while 905 had been vaccinated three times (boosted). The prevalence of severe or critical COVID-19 among patients was 11 percentage points lower among those vaccinated (40%) at least twice than among those unvaccinated (51%) (p＜0.001), while it was 10% points lower among those who had received a booster (41%) than among those unvaccinated (51%) (p＜0.001). Protection against severe or critical COVID-19 due to vaccination was significantly weakened by being older than 65 years, being male, or having diabetes, chronic heart disease, autoimmune disease, or chronic lung disease. Completing a full course of immunization with inactivated vaccine CoronaVac against SARS-CoV-2 can reduce the risk of severe or critical COVID-19 due to the Omicron BA.5 subvariant.

Discovery and development of COVID-19 vaccine from laboratory to clinic

The world has recently experienced one of the biggest and most severe public health disasters with severe acute respiratory syndrome coronavirus (SARS-CoV-2). SARS-CoV-2 is responsible for the coronavirus disease of 2019 (COVID-19) which is one of the most widespread and powerful infections affecting human lungs. Current figures show that the epidemic had reached 216 nations, where it had killed about 6,438,926 individuals and infected 590,405,710. WHO proclaimed the outbreak of the Ebola virus disease (EVD), in 2014 that killed hundreds of people in West Africa. The development of vaccines for SARS-CoV-2 becomes more difficult due to the viral mutation in its non-structural proteins (NSPs) especially NSP2 and NSP3, S protein, and RNA-dependent RNA polymerase (RdRp). Continuous monitoring of SARS-CoV-2, dynamics of the genomic sequence, and spike protein mutations are very important for the successful development of vaccines with good efficacy. Hence, the vaccine development for SARS-CoV-2 faces specific challenges starting from viral mutation. The requirement of long-term immunity development, safety, efficacy, stability, vaccine allocation, distribution, and finally, its cost is discussed in detail. Currently, 169 vaccines are in the clinical development stage, while 198 vaccines are in the preclinical development stage. The majority of these vaccines belong to the Ps-Protein subunit type which has 54, and the minor BacAg-SPV (Bacterial antigen-spore expression vector) type, at least 1 vaccination. The use of computational methods and models for vaccine development has revolutionized the traditional methods of vaccine development. Further, this updated review highlights the upcoming vaccine development strategies in response to the current pandemic and post-pandemic era, in the field of vaccine development.

Effects of COVID-19 vaccine type on Guillain-Barré syndrome: Two cases and a literature review

Guillain-Barré syndrome (GBS) is a rare but severe complication of COVID-19 vaccination. We report two cases of GBS following vaccination with the adenovirus vector vaccine ChAdOx1 nCoV-19 (Vaxzevria, AstraZeneca) and review the relevant literature. Relevant studies published between December 2020 and May 2022 including 881 patients with GBS were reviewed. GBS incidence and the need for mechanical ventilation were reported at a higher level among patients receiving Vaxzevria (n = 400). However, incidence cannot be accurately estimated from case reports. Thus, the true GBS rates following COVID-19 vaccination should be determined by population-based data.

Emerging heterologous mRNA-based booster strategies within the COVID-19 vaccine landscape

Messenger RNA (mRNA)-based vaccine platforms used for the development of mRNA-1273 and BNT162b2 have provided a robust adaptable approach to offer protection against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, as variants of concern (VoCs), such as omicron and associated sub-variants, emerge, boosting strategies must also adapt to keep pace with the changing landscape. Heterologous vaccination regimens involving the administration of booster vaccines different than the primary vaccination series offer a practical, effective, and safe approach to continue to reduce the global burden of coronavirus disease 2019 (COVID-19). To understand the immunogenicity, effectiveness, and safety of heterologous mRNA-based vaccination strategies, relevant clinical and real-world observational studies were identified and summarized. Overall, heterologous boosting strategies with mRNA-based vaccines that are currently available and those in development will play an important global role in protecting individuals from COVID-19 caused by emerging VoCs.

Immune Profile Determines Response to Vaccination against COVID-19 in Kidney Transplant Recipients

BACKGROUND AND AIM

Immune status profile can predict response to vaccination, while lymphocyte phenotypic alterations represent its effectiveness. We prospectively evaluated these parameters in kidney transplant recipients (KTRs) regarding Tozinameran (BNT162b2) vaccination.

METHOD

In this prospective monocenter observational study, 39 adult KTRs, on stable immunosuppression, naïve to COVID-19, with no protective humoral response after two Tozinameran doses, received the third vaccination dose, and, based on their immunity activation, they were classified as responders or non-responders. Humoral and cellular immunities were assessed at predefined time points (T0: 48 h before the first, T1: 48 h prior to the third and T2: three weeks after the third dose).

RESULTS

Responders, compared to non-responders, had a higher total and transitional B-lymphocyte count at baseline (96.5 (93) vs. 51 (52)cells/μL, p: 0.045 and 9 (17) vs. 1 (2)cells/μL, p: 0.031, respectively). In the responder group, there was a significant increase, from T0 to T1, in the concentrations of activated CD4+ (from 6.5 (4) to 10.08 (11)cells/μL, p: 0.001) and CD8+ (from 8 (19) to 14.76 (16)cells/μL, p: 0.004) and a drop in CD3+PD1+ T-cells (from 130 (121) to 30.44 (25)cells/μL, p: 0.001), while naïve and transitional B-cells increased from T1 to T2 (from 57.55 (66) to 1149.3 (680)cells/μL, p < 0.001 and from 1.4 (3) to 17.5 (21)cells/μL, p: 0.003). The percentages of memory and marginal zone B-lymphocytes, and activated CD4+, CD8+ and natural killer (NK) T-cells significantly increased, while those of naïve B-cells and CD3+PD1+ T-cells reduced from T0 to T1.

CONCLUSIONS

Responders and non-responders to the third BNT162b2 dose demonstrated distinct initial immune cell profiles and changes in cellular subpopulation composition following vaccination.

Optimizing SARS-CoV-2 Immunoassays for Specificity in Dengue-Co-Endemic Areas

Introduction The overlap in clinical presentation between COVID-19 and dengue poses challenges for diagnosis in co-endemic regions. Furthermore, there have been reports of antibody cross-reactivity between SARS-CoV-2 and dengue. Our research aims to evaluate SARS-CoV-2 antigens for serological testing while reducing the possibility of cross-reactivity with anti-dengue antibodies. Method Two hundred and ten serum samples were collected from 179 patients and divided into four panels. Panels 1 and 2 consisted of COVID-19-negative healthy donors (n=81) and pre-pandemic dengue patients (n=50), respectively. Alternatively, Panel 3 (n=19) was composed of reverse transcription-quantitative polymerase chain reaction (RT-qPCR)-positive samples collected within two weeks of COVID-19 symptom onset, while Panel 4 (n=60) was composed of positive samples collected after two weeks of symptom onset. Previously developed and characterized in-house SARS-CoV-2 spike-1 (S1), receptor binding domain (RBD), and nucleocapsid (N) immunoglobin G (IgG)-enzyme-linked immunosorbent assay (ELISA) assays were used for the study. Results Six dengue-positive sera cross-reacted with the RBD of SARS-CoV-2. However, only one dengue-positive sera cross-reacted with the S1 and N proteins of SARS-CoV-2. Co-immobilization of S1 and RBD in different ratios revealed an 80:20 (S1:RBD) ratio as optimal for achieving an overall 96.2% sensitivity with the least cross-reaction to anti-dengue antibodies. Conclusion Our findings indicated that SARS-CoV-2 RBD-based immunoassays present more cross-reactivity with anti-dengue antibodies than S1 and N proteins. Furthermore, co-immobilization of S1 and RBD reduces the cross-reactivity with anti-dengue antibodies compared to RBD, thereby increasing the immunoassay specificity without affecting overall sensitivity for the dengue-endemic areas.

Immunogenicity of Mix-and-Match CoronaVac/BNT162b2 Regimen versus Homologous CoronaVac/CoronaVac Vaccination: A Single-Blinded, Randomized, Parallel Group Superiority Trial

(1) Background: This study aimed to compare the immunogenicity of the mix-and-match CoronaVac/BNT162b2 vaccination to the homologous CoronaVac/CoronaVac regimen. (2) Methods: We conducted a simple-blinded randomized superiority trial to measure SARS-CoV-2 neutralization antibodies and anti-spike receptor binding domain (RBD) IgG concentrations in blood samples of participants who had received the first dose of CoronaVac vaccine followed by a dose of BNT162b2 or CoronaVac vaccine. The primary endpoint for immunogenicity was the serum-neutralizing antibody level with a percentage of inhibition at 90% at 21-35 days after the boost. A difference of 25% between groups was considered clinically relevant. (3) Results: Among the 240 eligible participants, the primary endpoint data were available for 100 participants randomly allocated to the mix-and-match group versus 99 participants randomly allocated to the homologous dose group. The mix-and-match regimen elicited significantly higher levels of neutralizing antibodies (median level of 96%, interquartile range (IQR) (95-97) versus median level of 94%, IQR (81-96) and anti-spike IgG antibodies (median level of 13,460, IQR (2557-29,930) versus median level of 1190, IQR (347-4964) compared to the homologous group. Accordingly, the percentage of subjects with a percentage of neutralizing antibodies > 90% was significantly higher in the mix-and-match group (90.0%) versus the homologous (60.6%). Interestingly, no severe events were reported within 30 days after the second dose of vaccination in both groups. (4) Conclusions: Our data showed the superiority of the mix-and-match CoronaVac/BNT162b2 vaccination compared to the CoronaVac/CoronaVac regimen in terms of immunogenicity, thus constituting a proof-of-concept study supporting the use of inactivated vaccines in a mix-and-match strategy while ensuring good immunogenicity and safety.

Short-term adverse effects of COVID-19 vaccines after the first, second, and booster doses: a cross-sectional survey from Punjab, Pakistan, and the implications

BACKGROUND

Safety and efficacy concerns regarding coronavirus disease 2019 (COVID-19) vaccines are common among the public and have a negative impact on their uptake. We aimed to report the adverse effects currently associated with the vaccine in Pakistan to build confidence among the population for its adoption.

METHODS

A cross-sectional study was conducted in five districts of the Punjab province of Pakistan between January and March 2022. The participants were recruited using convenience sampling. All data were analyzed using SPSS 22.

RESULTS

We recruited 1622 people with the majority aged between 25-45 years. Of these, 51% were female, including 27 pregnant women and 42 lactating mothers. Most participants had received the Sinopharm (62.6%) or Sinovac (17.8%) vaccines. The incidences of at least one side effect after the first (N = 1622), second (N = 1484), and booster doses (N = 219) of the COVID-19 vaccine were 16.5%, 20.1%, and 32%, respectively. Inflammation/erythema at the injection site, pain at the injection site, fever, and bone/muscle pain were common side effects of vaccination. No significant differences were observed in the adverse effect scores between all demographic variables except for pregnancy (P = 0.012) after the initial dose. No significant association was observed between any variable and the side effect scores of the second and booster doses of the vaccine.

CONCLUSIONS

Our study showed a 16-32% prevalence of self-reported side effects after the first, second, and booster COVID-19 vaccinations. Most adverse effects were mild and transient, indicating the safety of different COVID-19 vaccines.

COVID-19 Vaccines Status, Acceptance and Hesitancy among Maintenance Hemodialysis Patients: A Cross-Sectional Study and the Implications for Pakistan and Beyond

COVID-19 vaccine hesitancy continues to be a widespread problem in Pakistan due to various conspiracy beliefs, myths and misconceptions. Since the hemodialysis population is at a higher risk of contracting infections, we sought to investigate the current COVID-19 immunization status and reasons for any vaccine hesitancy among these patients in Pakistan. This cross-sectional study was conducted among maintenance hemodialysis patients at six hospitals in the Punjab Province of Pakistan. Data were collected anonymously using a questionnaire. A total of 399 hemodialysis patients took part in the survey, the majority of them were male (56%) and aged 45-64 years. A calculated 62.4% of the patients reported receiving at least one dose of the COVID-19 vaccine. Of those vaccinated (249), 73.5% had received two doses and 16.9% had received a booster dose. The most common reasons for vaccination were "being aware they were at high risk" (89.6%), "fear of getting infected" (89.2%) and "willingness to fight against COVID-19-pandemic" (83.9%). Of the 150 patients who had not yet been vaccinated, only 10 showed a willingness to take the COVID-19 vaccine. The major reasons for refusal included "COVID-19 is not a real problem" (75%), the "corona vaccine is a conspiracy (72.1%)" and "I don't need the vaccine" (60.7%). Our study revealed that only 62% patients receiving hemodialysis were partially or completely vaccinated against COVID-19. Consequently, there is a need to initiate aggressive approaches to educate this high-risk population in order to address their concerns with vaccine safety and efficacy as well as correct current myths and misconceptions to improve the COVID-19 immunization status in this population.

Compartmental mathematical modelling of dynamic transmission of COVID-19 in Rwanda

OBJECTIVES

Mathematical modelling is of interest to study the dynamics of coronavirus disease 2019 (COVID-19), and models such as SEIR (Susceptible-Exposed-Infected-Recovered) have been considered. This article describes the development of a compartmental transmission network model - Susceptible-Exposed-Quarantine-Infectious-Infectious, undetected-Infectious, home-based care-Hospitalized-Vaccinated-Recovered-Dead - to simulate the dynamics of COVID-19 in order to account for specific measures put into place by the Government of Rwanda to prevent further spread of the disease.

METHODS

The compartments of this model are connected by parameters, some of which are known from the literature, and others are estimated from available data using the least squares method. For the stability of the model, equilibrium points were determined and the basic reproduction number R 0 was studied; R ₀ is an indicator for contagiousness.

RESULTS

The model showed that secondary infections are generated from the exposed group, the asymptomatic group, the infected (symptomatic) group, the infected (undetected) group, the infected (home-based care) group and the hospitalized group. The formulated model was reliable and fit the data. Furthermore, the estimated R 0 of 2.16 shows that COVID-19 will persist without the application of control measures.

CONCLUSIONS

This article presents results regarding predicted spread of COVID-19 in Rwanda.

Parental COVID-19 Vaccine Hesitancy for Children and Its Influencing Factors: A Riyadh-Based Cross-Sectional Study

It is well known that vaccination is the best clinical approach for successfully controlling COVID-19 infection. Understanding the disparities in COVID-19 vaccination apprehension among parents in different societies is crucial for effectively implementing COVID-19 vaccination programs. This observational cross-sectional study was carried out in the Riyadh region of Saudi Arabia between February and April 2022. The validated questionnaire was shared with parents who had children between the ages of five and eleven years. The collected data were analyzed using descriptive and inferential statistical methods. Multinomial regression analysis was conducted to determine the factors significantly affecting vaccine-use decisions. Of the 699 participants, 83% of the mothers were between the ages of 35 and 44 years, 67% were university educated, and only 14% were healthcare workers. A large proportion of parents, with an age range of 18–34 years (p = 0.001), and those with a higher income group (p = 0.014), demonstrated significant vaccine hesitancy. Further, parents who received one or two vaccination doses were significantly (p = 0.02) more hesitant than those who received more than two doses of the vaccine. Furthermore, a significantly (p = 0.002) high percentage of parents who follow the Ministry of Health (MOH) guidelines for personal preventive measures were hesitant about their children’s vaccination. Concerns about side effects (31.4%) and a lack of safety data (31.2%) on the COVID-19 vaccines were the two most significant reasons for parents to develop vaccine hesitancy. Social media (24.3%), poor perceived immunity (16.3 %), and news articles (15.5%) were the top three contributors to this hesitancy. Vaccinated parents were 8.21 times more likely to be vaccination-hesitant than non-vaccinated parents. Additionally, parents with less education and a COVID-19-positive child at home increased the odds of vaccine hesitancy by 1.66 and 1.48 times, respectively. Overall, one-third of the parents were not prepared to vaccinate their children, and one-quarter of the respondents had not decided about vaccination. This study shows that parents in Riyadh are generally reluctant to vaccinate their children against COVID-19. As social media is a primary source of information for parents, public health professionals should utilize the platform to encourage parents to support vaccine acceptance.

Breast Cancer Management in the Era of Covid-19; Key Issues, Contemporary Strategies, and Future Implications

During the COVID-19 pandemic, several priority diseases were not getting sufficient attention. Whilst breast cancer is a fatal disease affecting millions worldwide, identification and management of these patients did not initially attract critical attention to minimize the impact of lockdown, post-lockdown, and other measures. Breast cancer patients' conditions may not remain stable without proper care, worsening their prognosis. Proper care includes the timely instigation of surgery, systemic therapy, and psychological support. This includes low-and middle-income countries where there are already concerns with available personnel and medicines to adequately identify and treat these patients. Consequently, there was a need to summarize the current scenario regarding managing breast cancer care during COVID-19 across all countries, including any guidelines developed. We systematically searched three scientific databases and found 76 eligible articles covering the medical strategies of high-income countries versus LMICs. Typically, diagnostic facilities in hospitals were affected at the beginning of the pandemic following the lockdown and other measures. This resulted in more advanced-stage cancers being detected at initial presentation across countries, negatively impacting patient outcomes. Other than increased telemedicine, instigating neo-adjuvant endocrine therapy more often, reducing non-essential visits, and increasing the application of neo-adjuvant chemotherapy to meet the challenges, encouragingly, there was no other significant difference among patients in high-income versus LMICs. Numerous guidelines regarding patient management evolved during the pandemic to address the challenges posed by lockdowns and other measures, which were subsequently adopted by various high-income countries and LMICs to improve patient care. The psychological impact of COVID-19 and associated lockdown measures, especially during the peak of COVID-19 waves, and the subsequent effect on the patient's mental health must also be considered in this high-priority group. We will continue to monitor the situation to provide direction in future pandemics.

Intensive Care during the COVID-19 Pandemic

The novel coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in a sudden sharp rise in hospitalizations for pneumonia with multiorgan disease [...].

Differences in BNT126b2 and ChAdOx1 Homologous Vaccination Antibody Response among Teachers in Poznan, Poland

Children are among the best vectors to spread respiratory viruses, including emerging variants of SARS-CoV-2 due to the asymptomatic or relatively mild course of infection and simultaneously high titres of pathogens in the respiratory tract. Therefore, individuals who have constant contact with children, e.g., teachers should be vaccinated against COVID-19 as essential workers within the first phases of a vaccination campaign. In Poland, primary and secondary school teachers were vaccinated with ChAdOx1 from February 2021 with a three month interval between the two doses, while lecturers at medical universities, who are simultaneously healthcare workers, received the BNT126b2 vaccine from December 2020 with three weeks between the first and second doses. The aim of this study was to compare the antibody responses at two weeks and three months after vaccination and to estimate the vaccine effectiveness against COVID-19 among infection-naïve teachers vaccinated with mRNA and a vector vaccine. We found that the anti-SARS-CoV-2 spike protein antibodies were significantly higher among the lecturers but antibody waning was slower among the schoolteachers. However, those vaccinated with ChAdOx1 complained significantly more often of vaccine side effects. In addition, during the three months after the second vaccine dose no study participants were infected with SARS-CoV-2. The BNT126b2 vaccine gave higher antibody titres in comparison with ChAdOx1 but protection against COVID-19 in both cases was similar. Moreover, we did not find any anti-SARS-CoV-2 nucleoprotein antibodies at two weeks as well as at three months after vaccination among the study participants, which shows a very high vaccine effectiveness in the occupational group with a high SARS-CoV-2-infection risk.

A statistical analysis of tweets on covid-19 vaccine hesitancy utilizing opinion mining: an Indian perspective

The world witnessed the emergence of a deadly virus in December 2019, later named COVID-19. The virus was found to be highly contagious, and so people across the world were highly prone to be affected by the virus. Being a virus-borne disease, developing a vaccine was one of the most promising remedies. Thus, research organizations across the globe started working on developing the vaccine. However, it was later found by many researchers that a large number of people were hesitant to receive the vaccine. This paper aims to study the acceptance and hesitancy levels of people in India and compares them with the acceptance and hesitancy levels of people from the UK, the USA, and the rest of the world by analyzing their tweets on Twitter. For this study, 2,98,452 tweets were fetched from January 2020 to March 2022 from Twitter, and 1,84,720 tweets from 1,22,960 unique users were selected based on their country of origin. Machine learning based Sentiment analysis is then used to evaluate and analyze the tweets. The paper also proposes an NLP-based algorithm to perform opinion mining on Twitter data. The study found the public sentiment of the Indian population to be 63% positive, 28% neutral, and 9% negative. While the worldwide sentiment distribution is 45% positive, 34% neutral, and 21% negative, the USA has 42% positive, 34% neutral, and 23% negative and the UK has 50% positive, 29% neutral, and 21% negative. Also, sentiment analysis for individual vaccines in Indian context resulted in "Covaxin" with the highest positive sentiment at 43% followed by "Covishield" at 36%. The outcome of this work yields an insight into the public perception of the COVID-19 vaccine and thus can be used to formulate policies for existing and future vaccine campaigns. This study becomes more relevant as it is the consolidated opinion of Indian people, which is versatile in nature.

COVID-19 vaccination and liver disease

Various vaccines against severe acute respiratory syndrome coronavirus 2 have been developed in response to the coronavirus disease 2019 (COVID-19) global pandemic, several of which are highly effective in preventing COVID-19 in the general population. Patients with chronic liver diseases (CLDs), particularly those with liver cirrhosis, are considered to be at a high risk for severe COVID-19 and death. Given the increased rates of disease severity and mortality in patients with liver disease, there is an urgent need to understand the efficacy of vaccination in this population. However, the data regarding efficacy and safety of COVID-19 vaccination in patients with CLDs is limited. Indeed, several organ-specific or systemic immune-mediated side effects following COVID-19 vaccination, including liver injury similar to autoimmune hepatitis, have been recently reported. Although the number of cases of vaccine-related liver injury is increasing, its frequency, clinical course, and mechanism remain unclear. Here, we review the current findings on COVID-19 vaccination and liver disease, focusing on: (1) The impact of COVID-19 in patients with CLD; (2) The efficacy, safety, and risk-benefit profiles of COVID-19 vaccines in patients with CLD; and (3) Liver injury following COVID-19 vaccination.

Association between γ-Glutamyl Transpeptidase and SARS-CoV-2 Spike Antibody Titers among BNT162b2 Vaccine Recipients

BACKGROUND

Increased γ-glutamyl transpeptidase (GGT) levels can deplete plasma glutathione, which in turn impairs immune regulation; however, evidence on GGT levels and post-vaccine immunogenicity is lacking.

OBJECTIVE

To examine the association between GGT and SARS-CoV-2 spike IgG antibodies.

METHODS

Participants were 1479 medical staff (aged 21 to 75 years) who received a SARS-CoV-2 antibody test after their second vaccine and whose GGT levels were measured before the vaccine rollout. Elevated and highly elevated GGT levels were defined as 51-80 and ≥81 U/L, respectively. Multivariable linear regression was used to calculate the means of SARS-CoV-2 spike IgG.

RESULTS

In a basic model, both elevated and highly elevated GGT levels were associated with significantly lower antibody titers. The ratio of mean (95% CI) was 0.83 (0.72-0.97) and 0.69 (0.57-0.84) for elevated and highly elevated GGT levels, respectively. However, these associations were largely attenuated after additional adjustment for potential confounders. An inverse association between GGT levels and antibody titers was found in women [0.70 (0.51-0.97)], normal-weight adults [0.71 (0.51-0.98)], and non-drinkers [0.73 (0.46-1.14)] but not in men, overweight adults, and alcohol drinkers.

CONCLUSIONS

Circulating GGT concentrations were associated with the humoral immune response after COVID-19 vaccination, but this relationship could be ascribed to confounders such as sex, BMI, and alcohol drinking rather than GGT per se.

Maintaining immunological memory to the SARS-CoV-2 virus during a pandemic

The question of the duration and effectiveness of post-infection immunity to SARS-CoV-2 and its comparison with post-vaccination remains at the center of study by many researchers. The aim of the work was to study the duration of maintaining post-infection and post-vaccination immunity to the SARS-CoV-2 virus, as well as the formation of hybrid (vaccination after infection) and breakthrough (repeated disease or disease after vaccination) immunity in the context of an ongoing pandemic. 107 adults who had mild or moderate COVID-19 3-18 months after the disease and 30 people vaccinated twice with the Sputnik V vaccine were examined 1-6 times. Antibodies to the SARS-CoV-2 virus were determined by ELISA on the SARS-CoV-2-IgG quantitative-ELISA-BEST test systems. The avidity of antibodies was determined by additional incubation with and without denaturing solution. Mononuclear cells were isolated from blood by gradient centrifugation, incubated with and without coronavirus S-protein for 20 hours, stained with fluorescently labeled antibodies, and the percentage of CD8highCD107a+ was counted on a FACSCanto II cytometer. It was shown that in the group of reconvalescent and vaccinated, the level of antibodies specific to the virus decreased more pronounced in individuals with an initially high humoral response, but after 9 months the decrease slowed down and reached a plateau. The avidity of antibodies rose to 50% and persisted for 18 months. Cellular immunity in recovered patients did not change for 1.5 years, while in vaccinated patients it gradually decreased after 6 months, but remained at a detectable level. After revaccination of the vaccinated, a significant increase in the level of antibodies, avidity to 67.6% and cellular immunity to the initial level was noted. Hybrid immunity turned out to be significantly higher than post-infection and post-vaccination immunity. The level of antibodies increased to 1218.2 BAU/ml, avidity to 69.85%, and cellular immunity to 9.94%. Breakthrough immunity was significantly higher than after the first disease. The level of antibodies rose to 1601 BAU/ml, avidity - up to 81.6%, cellular immunity - up to 13.71%. Using the example of dynamic observation of four COVID-19 reconvalescents, it has been shown that in the context of the ongoing pandemic and active mutation of the coronavirus, natural boosting occurs both asymptomatically and as a result of a mild re-infection, which prevents the disappearance of humoral and cellular immunity specific to SARS-CoV -2.

Awareness and acceptance of COVID-19 vaccines and associated factors among pharmacy students in Zambia

Aim

This study aimed to assess the awareness and acceptance of COVID-19 vaccines and associated factors among pharmacy students in Zambia.

Materials and Methods

We conducted a cross-sectional study among 326 undergraduate pharmacy students in Lusaka, Zambia, from February to April 2021. Data were analysed using Stata version 16.1. Multivariable logistic regression was used to determine key factors influencing vaccine acceptance.

Results

Of the 326 participants, 98.8% were aware of the COVID-19 vaccines, but only 24.5% would accept vaccination. Compared to other religions, being of Christian faith was associated with reduced odds of awareness of the COVID-19 vaccine (aOR=0.01, 95% CI: 0.01-0.20). Conversely, factors associated with vaccine acceptance were being male, single and unemployed. Compared to females, male respondents were 86% more likely to accept the vaccine if it was made available (aOR=1.86, 95% CI: 1.10-3.14). In addition, unmarried respondents were 2.65 times as likely to accept vaccination than married respondents (aOR=2.65, 95% CI: 1.06-6.63). Conversely, unemployed respondents were less likely to accept vaccination than their employed counterparts (aOR=0.32, 95% CI: 0.16-0.46). Barriers to the acceptability of the vaccine were possible side effects (78.5%) and scepticism about its effectiveness (10.2%).

Conclusion

There was significant vaccine hesitancy toward COVID-19 vaccines among Zambian pharmacy students despite their awareness of the vaccines. Health authorities must work collaboratively with training institutions to mitigate vaccine hesitancy, especially with healthcare students being a key part of the future healthcare workforce overseeing disease prevention strategies.

Liver injury after SARS-CoV-2 vaccination: Features of immune-mediated hepatitis, role of corticosteroid therapy and outcome

BACKGROUND AND AIMS

A few case reports of autoimmune hepatitis-like liver injury have been reported after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. We evaluated clinical features, treatment response and outcomes of liver injury following SARS-CoV-2 vaccination in a large case series.

APPROACH AND RESULTS

We collected data from cases in 18 countries. The type of liver injury was assessed with the R-value. The study population was categorized according to features of immune-mediated hepatitis (positive autoantibodies and elevated immunoglobulin G levels) and corticosteroid therapy for the liver injury. We identified 87 patients (63%, female), median age 48 (range: 18-79) years at presentation. Liver injury was diagnosed a median 15 (range: 3-65) days after vaccination. Fifty-one cases (59%) were attributed to the Pfizer-BioNTech (BNT162b2) vaccine, 20 (23%) cases to the Oxford-AstraZeneca (ChAdOX1 nCoV-19) vaccine and 16 (18%) cases to the Moderna (mRNA-1273) vaccine. The liver injury was predominantly hepatocellular (84%) and 57% of patients showed features of immune-mediated hepatitis. Corticosteroids were given to 46 (53%) patients, more often for grade 3-4 liver injury than for grade 1-2 liver injury (88.9% vs. 43.5%, p = 0.001) and more often for patients with than without immune-mediated hepatitis (71.1% vs. 38.2%, p = 0.003). All patients showed resolution of liver injury except for one man (1.1%) who developed liver failure and underwent liver transplantation. Steroid therapy was withdrawn during the observation period in 12 (26%) patients after complete biochemical resolution. None had a relapse during follow-up.

CONCLUSIONS

SARS-CoV-2 vaccination can be associated with liver injury. Corticosteroid therapy may be beneficial in those with immune-mediated features or severe hepatitis. Outcome was generally favorable, but vaccine-associated liver injury led to fulminant liver failure in one patient.

High Anti-CoV2S Antibody Levels at Hospitalization Are Associated with Improved Survival in Patients with COVID-19 Vaccine Breakthrough Infection

BACKGROUND

Although vaccination against COVID-19 is highly effective, breakthrough infections occur, often leading to severe courses and death. The extent of protection provided by individual antibody levels in breakthrough infections is still unknown and cut-off levels have yet to be determined.

METHODS

In 80 consecutive fully vaccinated patients hospitalized between August and December 2021 with COVID-19 breakthrough infection (Delta variant), anti-CoV2S antibody levels were analyzed for the endpoint of death.

RESULTS

Ten out of the 12 patients who died (83.3%) had antibody levels < 600 U/mL; 5 (41.7%) of these had antibody levels < 200 U/mL. Only 2 patients with a level of >600 U/mL died from vaccine breakthrough infection. Correction for the number of comorbidities and age revealed that anti-CoV2S antibody levels at the time of hospitalization were a significant predictor for reduced risk of death (OR = 0.402 for every 1000 U/mL, p = 0.018).

CONCLUSIONS

In this retrospective data analysis, we show that almost all patients who died from COVID-19 vaccine breakthrough infection had antibody levels < 600 U/mL, most of them below 200 U/mL. In logistic regression corrected for the number of comorbidities and age, anti-CoV2S antibody levels at the time of hospitalization proved to be a significantly protective predictor against death.

Safety after BBIBP-CorV (Sinopharm) COVID-19 Vaccine in Adolescents Aged 10-17 Years in Thailand

Coronavirus disease 2019 affected child health and impacted learning because of the resulting onsite school closures. This prospective cohort study included children aged 10-17 who received two 4 µg doses of BBIBP-CorV administered intramuscularly 21-28 days apart. To assess vaccine safety, 36,808 participants were then followed with paper- and web-based online questionnaire surveys that captured local and systemic reactogenicities following vaccine administration on days 1, 7, and 30. Among participants, 76% (27,880) reported reactogenicity within the first 24 h and 7 days following the first dose. Half (51.41%) of participants experienced pain at the injection site; the majority of cases were mild in severity. Injection site tenderness (37.93%) was another common local reaction. Fatigue (37.89%), myalgia (33.56%), and headache (26.76%) were the most common systemic reactions. On days 2-7 after the first dose, 25.85% of participants experienced adverse reactions. Following the second dose, reactogenicity was 7.6% and 1.09% within 24 h and between days 2-7. The majority of reactions were of mild to moderate severity. We report that two doses of the BBIBP-CorV caused mild to moderate side effects in adolescents in Thailand. The findings confirm the vaccine's safety profile in this age group.

Prerequisite for COVID-19 Prediction: A Review on Factors Affecting the Infection Rate

Since the year 2020, coronavirus disease 2019 (COVID-19) has emerged as the dominant topic of discussion in the public and research domains. Intensive research has been carried out on several aspects of COVID-19, including vaccines, its transmission mechanism, detection of COVID-19 infection, and its infection rate and factors. The awareness of the public related to the COVID-19 infection factors enables the public to adhere to the standard operating procedures, while a full elucidation on the correlation of different factors to the infection rate facilitates effective measures to minimize the risk of COVID-19 infection by policy makers and enforcers. Hence, this paper aims to provide a comprehensive and analytical review of different factors affecting the COVID-19 infection rate. Furthermore, this review analyses factors which directly and indirectly affect the COVID-19 infection risk, such as physical distance, ventilation, face masks, meteorological factor, socioeconomic factor, vaccination, host factor, SARS-CoV-2 variants, and the availability of COVID-19 testing. Critical analysis was performed for the different factors by providing quantitative and qualitative studies. Lastly, the challenges of correlating each infection risk factor to the predicted risk of COVID-19 infection are discussed, and recommendations for further research works and interventions are outlined.

SARS-CoV-2 vaccination and risk of severe COVID-19 outcomes in patients with autoimmune hepatitis

BACKGROUND

Data regarding outcome of Coronavirus disease 2019 (COVID-19) in vaccinated patients with autoimmune hepatitis (AIH) are lacking. We evaluated the outcome of COVID-19 in AIH patients who received at least one dose of Pfizer- BioNTech (BNT162b2), Moderna (mRNA-1273) or AstraZeneca (ChAdOx1-S) vaccine.

PATIENTS AND METHODS

We performed a retrospective study on AIH patients with COVID-19. The outcomes of AIH patients who had acute respiratory syndrome coronavirus 2 (SARS-CoV-2) breakthrough infection after at least one dose of COVID-19 vaccine were compared to unvaccinated patients with AIH. COVID-19 outcome was classified according to clinical state during the disease course as: (i) no hospitalization, (ii) hospitalization without oxygen supplementation, (iii) hospitalization with oxygen supplementation by nasal cannula or mask, (iv) intensive care unit (ICU) admission with non-invasive mechanical ventilation, (v) ICU admission with invasive mechanical ventilation or (vi) death, and data was analyzed using ordinal logistic regression.

RESULTS

We included 413 (258 unvaccinated and 155 vaccinated) patients (81%, female) with a median age of 52 (range: 17-85) years at COVID-19 diagnosis. The rates of hospitalization were (36.4% vs. 14.2%), need for any supplemental oxygen (29.5% vs. 9%) and mortality (7% vs. 0.6%) in unvaccinated and vaccinated AIH patients with COVID-19. Having received at least one dose of SARS-CoV-2 vaccine was associated with a significantly lower risk of worse COVID-19 severity, after adjusting for age, sex, comorbidities and presence of cirrhosis (adjusted odds ratio [aOR] 0.18, 95% confidence interval [CI], 0.10-0.31). Overall, vaccination against SARS-CoV-2 was associated with a significantly lower risk of mortality from COVID-19 (aOR 0.20, 95% CI 0.11-0.35).

CONCLUSIONS

SARS-CoV-2 vaccination significantly reduced the risk of COVID-19 severity and mortality in patients with AIH.

COVID-19 Infection and Response to Vaccination in Chronic Kidney Disease and Renal Transplantation: A Brief Presentation

Chronic kidney disease (CKD) is associated with phenotypic and functional changes in the immune system, followed by detrimental clinical consequences, such as severe infections and defective response to vaccination. Two years of the pandemic, due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), have undoubtedly changed the world; however, all efforts to confront infection and provide new generation vaccines tremendously improved our understanding of the mechanisms of the immune response against infections and after vaccination. Humoral and cellular responses to vaccines, including mRNA vaccines, are apparently affected in CKD patients, as elimination of recent thymic emigrant and naïve lymphocytes and regulatory T-cells, together with contraction of T-cell repertoire and homeostatic proliferation rate, which characterized CKD patients are responsible for impaired immune activation. Successful renal transplantation will restore some of these changes, although several epigenetic changes are irreversible and even accelerated by the induction of immunosuppression. Response to vaccination is definitely impaired among both CKD and RT patients. In the present review, we analyzed the differences in immune response after vaccination between these patients and healthy individuals and depicted specific parameters, such as alterations in the immune system, predisposing to this deficient response.

A prospective multicenter study on cutaneous reactions reported after Sinopharm COVID-19 vaccination

BACKGROUND

The new coronavirus COVID-19 pandemic has had an unprecedented impact on global health and economic growth. A widely used vaccine is the weakened inactivated severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) virus (Sinopharm). Following major SARS-CoV-2 vaccination campaigns, cutaneous symptoms are on the rise.

METHODS

This study is a prospective observational study evaluating cutaneous reactions and time of recovery after Sinopharm vaccination. The cases involved were over the age of 18. The data were anonymized. On the registry's vaccine section, we tracked vaccination dates, skin reactions, and recovery times. All respondents who reported only a cutaneous reaction to the first vaccination dose received a follow-up contact asking about a second vaccination dose cutaneous reaction.

RESULTS

The study included 4560 cases. The mean age of all studied cases was 41.2 ± 6.1 years. There were dermatologic complications in 1190 patients (26.1%). There was induration at the injection site in 495 patients (10.9%), urticaria in 210 patients (4.6%), morbilliform eruption in 375 patients (8.2%), flare of skin site in 105 patients (2.3%), and angioedema in 105 patients (2.3%). The mean recovery days in all studied patients were 2.92 ± 0.94 days with a minimum recovery period of 2 days and a maximum of 7 days.

CONCLUSIONS

Because Sinopharm's cutaneous reactions are frequently mild and self-limiting, vaccination should not be discouraged based on these findings. If the first vaccine dose creates a cutaneous reaction, there is no need to skip the second dose.

Effectiveness and Cost-Effectiveness of Inactivated Vaccine to Address COVID-19 Pandemic in China: Evidence From Randomized Control Trials and Real-World Studies

Objective

This study aimed to determine the efficacy, effectiveness, and cost-effectiveness of inactivated COVID-19 vaccines (CoronaVac and BBIBP-CorV) in China using existing international clinical trials and real-world evidence.

Methods

Through a search of PubMed, Embase, Web of Science, and CNKI, studies investigating the effectiveness of inactivated COVID-19 vaccines were identified, and a meta-analysis was undertaken to synthesize the vaccine efficacy and effectiveness data. Moreover, a decision-analytic model was developed to estimate the cost-effectiveness of inactivated vaccines for combating the COVID-19 pandemic in the Chinese context from a societal perspective. Results of the meta-analysis, along with cost data from official websites and works of literature were used to populate the model. Sensitivity analysis was performed to test the robustness of the model results.

Results

A total of 24 studies were included in the meta-analysis. In comparison to no immunization, the effectiveness of inactivated vaccine against COVID-19 infection, hospitalization, ICU admission and death were 65.18% (95% CI 62.62, 67.75), 79.10% (95% CI 71.69, 86.51), 90.46% (95% CI 89.42, 91.50), and 86.69% (95% CI 85.68, 87.70); and the efficacy against COVID-19 infection and hospitalization were 70.56% (95% CI 57.87, 83.24) and 100% (95% CI 61.72, 100). Inactivated vaccine vaccination prevented more infections, hospitalizations, ICU admissions, and deaths with lower total costs, thus was cost-saving from a societal perspective in China. Base-case analysis results were robust in the one-way sensitivity analysis, and the percentage of ICU admission or death and direct medical cost ranked the top influential factors in our models. In the probabilistic sensitivity analysis, vaccination had a 100% probability of being cost-effective.

Conclusion

Inactivated vaccine is effective in preventing COVID-19 infection, hospitalization, ICU admission and avoiding COVID-19 related death, and COVID-19 vaccination program is cost-saving from societal perspective in China.

Protocol of an Exploratory Single-Arm Study to Evaluate the Safety and Immunogenicity of KD-414 as a Booster Vaccine for SARS-CoV-2 in Healthy Adults (KAPIVARA)

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic is currently ongoing, and there have been significant efforts in the development of COVID-19 vaccines. However, the neutralizing antibody titers in vaccinated individuals are reported to progressively decrease over time. Japanese pharmaceutical companies have published the results of Phase I and II studies on the safety and efficacy of different vaccines. Final clinical trials will be conducted with the aim of practical application by March 2023. To effectively utilize vaccines developed by Japanese companies, the efficacy and safety of a booster dose (i.e., third vaccination) must be evaluated among individuals who have received three doses of different vaccines.

METHODS

This protocol describes a study that aims to examine the effect of a booster dose of "KD-414", a novel Japanese inactivated vaccine, on antibody titers among participants involved in a previous study. Volunteers in this protocol will be recruited from participants in the previous study and immunized with KD-414 after obtaining consent. The antibody titers, before and after immunization with KD-414, among participants who previously received two doses of the BNT162b2 mRNA vaccine, will be comparatively analyzed.

DISCUSSION

The reactogenicity and immunogenicity of seven different COVID-19 vaccines including an inactivated vaccine as a third dose after two doses of ChAdOx1 nCov-19 or BNT162b2, has been tested previously, and found to be superior to control (quadrivalent meningococcal conjugate vaccine) regardless of which vaccine had been received during the initial course. This suggests that many types of third booster doses are efficacious. It is anticipated that this study will provide evidence of the safety and immunogenicity of KD-414 as a booster vaccine, which will have profound public health implications.

Willingness to accept COVID-19 vaccination among people living with HIV in a high HIV prevalence community

BACKGROUND

People living with HIV (PLWH) may have a poorer prognosis with COVID-19 infection and are an important population for COVID-19 vaccination. We assessed the willingness and reasons for COVID-19 vaccine acceptance or hesitancy among PLWH in South Africa.

METHODS

We conducted a cross-sectional study consisting of telephone interviews with a randomly selected subset of participants enrolled in a prospective observational cohort study evaluating a decentralized antiretroviral therapy (ART) delivery program in South Africa. Questions assessed willingness to accept a future COVID-19 vaccine, concerns regarding COVID-19 vaccination, and overall vaccine confidence. Interviews were conducted between September 2020 and January 2021. We evaluated participant demographics, sources of COVID-19 information, stigma and medical mistrust, uptake of non-pharmaceutical interventions, and socioeconomic impacts of the COVID-19 pandemic as potential covariates of willingness to accept vaccination.

RESULTS

We completed interviews with 213 participants; 153 (72%) were female, median age 35y, and 100 (47%) had completed secondary school. Among the participants, 121 (57%) were willing to accept future vaccination, 46 (22%) were unsure, and 45 (21%) stated they did not intend to be vaccinated. Fear of side effects, reported by 42 (20%), was the most common concern about COVID-19 vaccination. Older age was associated with willingness to accept vaccination (aOR 1.75 for every 10-year increase in age, 95% CI 1.10-2.78, p = 0.02), while higher medical mistrust related to COVID-19 (aOR 0.21, 95% CI 0.093-0.45, p < 0.001) and use of social media for COVID-19 information (aOR 0.30, 95% CI 0.11-0.84, p = 0.02) were associated with lower willingness to accept vaccination.

CONCLUSIONS

In this cohort of PLWH in South Africa, over half were willing to accept COVID-19 vaccination, although a substantial proportion remained unsure or were not willing to be vaccinated. Public health messaging should emphasize the safety and efficacy of COVID-19 vaccination and address misinformation and medical mistrust among PLWH. Ongoing efforts to ensure access to COVID-19 vaccines for vulnerable populations are crucial.

Booster Doses of Anti COVID-19 Vaccines: An Overview of Implementation Policies among OECD and EU Countries

The need for an anti-COVID-19 booster dose posed an organizational challenge for health policy makers worldwide. Therefore, this study aimed to explore the health policies regarding the booster dose through an overview of recommendations issued in high-income countries. Between 10 November and 16 December 2021, the authors searched for state-level official documents about the offer of the booster dose, considering the 43 countries belonging to the European Union (EU) or the Organisation for Economic Co-operation and Development (OECD). Mainly due to the lack of English translation, 15 countries were excluded. A total of 135 documents were selected. Almost all the countries started administering the booster dose between September and November 2021. The most used products were mRNA vaccines, followed by Vaxzevria-AstraZeneca and Jcovden-Janssen/Johnson & Johnson. All countries established criteria to define categories of individuals to be vaccinated as a priority. A six/five-months interval was the main choice for general population vaccinated with mRNA vaccines, while shorter intervals were chosen for vulnerable individuals or other vaccines. Despite diversities related to the differences in health systems, economical resources, and population numbers, and the need to adapt all these factors to a massive vaccination campaign, a progressive convergence towards the same vaccination policies was highlighted.

Co-Infections, Secondary Infections, and Antimicrobial Use in Patients Hospitalized with COVID-19 during the First Five Waves of the Pandemic in Pakistan; Findings and Implications

Background: COVID-19 patients are typically prescribed antibiotics empirically despite concerns. There is a need to evaluate antibiotic use among hospitalized COVID-19 patients during successive pandemic waves in Pakistan alongside co-infection rates. Methods: A retrospective review of patient records among five tertiary care hospitals during successive waves was conducted. Data were collected from confirmed COVID-19 patients during the first five waves. Results: 3221 patients were included. The majority were male (51.53%), residents from urban areas (56.35%) and aged >50 years (52.06%). Cough, fever and a sore throat were the clinical symptoms in 20.39%, 12.97% and 9.50% of patients, respectively. A total of 23.62% of COVID-19 patients presented with typically mild disease and 45.48% presented with moderate disease. A high prevalence of antibiotic prescribing (89.69%), averaging 1.66 antibiotics per patient despite there only being 1.14% bacterial co-infections and 3.14% secondary infections, was found. Antibiotic use significantly increased with increasing severity, elevated WBCs and CRP levels, a need for oxygen and admittance to the ICU; however, this decreased significantly after the second wave (p < 0.001). Commonly prescribed antibiotics were piperacillin plus an enzyme inhibitor (20.66%), azithromycin (17.37%) and meropenem (15.45%). Common pathogens were Staphylococcus aureus (24.19%) and Streptococcus pneumoniae (20.96%). The majority of the prescribed antibiotics (93.35%) were from the WHO’s “Watch” category. Conclusions: Excessive prescribing of antibiotics is still occurring among COVID-19 patients in Pakistan; however, rates are reducing. Urgent measures are needed for further reductions.

SARS-CoV-2 reinfections: Overview of efficacy and duration of natural and hybrid immunity

Seroprevalence surveys suggest that more than a third and possibly more than half of the global population has been infected with SARS-CoV-2 by early 2022. As large numbers of people continue to be infected, the efficacy and duration of natural immunity in terms of protection against SARS-CoV-2 reinfections and severe disease is of crucial significance for the future. This narrative review provides an overview on epidemiological studies addressing this issue. National surveys covering 2020-2021 documented that a previous SARS-CoV-2 infection is associated with a significantly reduced risk of reinfections with efficacy lasting for at least one year and only relatively moderate waning immunity. Importantly, natural immunity showed roughly similar effect sizes regarding protection against reinfection across different SARS-CoV-2 variants, with the exception of the Omicron variant for which data are just emerging before final conclusions can be drawn. Risk of hospitalizations and deaths was also reduced in SARS-CoV-2 reinfections versus primary infections. Observational studies indicate that natural immunity may offer equal or greater protection against SARS-CoV-2 infections compared to individuals receiving two doses of an mRNA vaccine, but data are not fully consistent. The combination of a previous SARS-CoV-2 infection and a respective vaccination, termed hybrid immunity, seems to confer the greatest protection against SARS-CoV-2 infections, but several knowledge gaps remain regarding this issue. Natural immunity should be considered for public health policy regarding SARS-CoV-2.

Kinetics of the Neutralizing and Spike SARS-CoV-2 Antibodies following the Sinovac Inactivated Virus Vaccine Compared to the Pfizer mRNA Vaccine in Singapore

Introduction: We compared the early total spike antibody (S-Ab) and neutralizing antibody (N-Ab) responses to two vaccines. Methods: We studied 96 Pfizer and 34 Sinovac vaccinees over a 14-month period from January 2021 to February 2022. All vaccinees received three doses of one type of vaccine. Antibody levels (Roche Elecsys total S-Ab and the Snibe N-Ab) were tested 10 days after the first dose, 20 days after the second dose, and 20 days after the booster dose. Results: At all time points, the mRNA vaccine generated higher S-Ab and N-Ab responses than the inactivated virus vaccine (S-Ab: first dose 2.48 vs. 0.4 BAU/mL, second dose 2174 vs. 98 BAU/mL, third dose 15,004 vs. 525 BAU/mL; N-Ab: first dose 0.05 vs. 0.02 µg/mL, second dose 3.48 vs. 0.38 µg/mL, third dose 19.8 vs. 0.89 µg/mL). mRNA vaccine recipients had a 6.2/22.2/28.6-fold higher S-Ab and 2.5/9.2/22.2-fold higher N-Ab response than inactivated virus vaccine recipients after the first/second/third inoculations, respectively. Mann–Whitney U analysis confirmed the significant difference in S-Ab and N-Ab titers between vaccination groups at each time point. Conclusions: The mRNA vaccines generated a more robust S-Ab and N-Ab response than the inactivated virus vaccine at all time points after the first, second, and third vaccinations.

Microfluidics Technology in SARS-CoV-2 Diagnosis and Beyond: A Systematic Review

With the progression of the COVID-19 pandemic, new technologies are being implemented for more rapid, scalable, and sensitive diagnostics. The implementation of microfluidic techniques and their amalgamation with different detection techniques has led to innovative diagnostics kits to detect SARS-CoV-2 antibodies, antigens, and nucleic acids. In this review, we explore the different microfluidic-based diagnostics kits and how their amalgamation with the various detection techniques has spearheaded their availability throughout the world. Three other online databases, PubMed, ScienceDirect, and Google Scholar, were referred for articles. One thousand one hundred sixty-four articles were determined with the search algorithm of microfluidics followed by diagnostics and SARS-CoV-2. We found that most of the materials used to produce microfluidics devices were the polymer materials such as PDMS, PMMA, and others. Centrifugal force is the most commonly used fluid manipulation technique, followed by electrochemical pumping, capillary action, and isotachophoresis. The implementation of the detection technique varied. In the case of antibody detection, spectrometer-based detection was most common, followed by fluorescence-based as well as colorimetry-based. In contrast, antigen detection implemented electrochemical-based detection followed by fluorescence-based detection, and spectrometer-based detection were most common. Finally, nucleic acid detection exclusively implements fluorescence-based detection with a few colorimetry-based detections. It has been further observed that the sensitivity and specificity of most devices varied with implementing the detection-based technique alongside the fluid manipulation technique. Most microfluidics devices are simple and incorporate the detection-based system within the device. This simplifies the deployment of such devices in a wide range of environments. They can play a significant role in increasing the rate of infection detection and facilitating better health services.

Willingness to accept COVID-19 vaccination among people living with HIV in a high HIV prevalence community

Background People living with HIV (PLWH) may have a poorer prognosis with COVID-19 infection and are an important population for COVID-19 vaccination. We assessed the willingness and reasons for COVID-19 vaccine acceptance or hesitancy among PLWH in South Africa. Methods We conducted a cross-sectional study consisting of telephone interviews with a randomly selected subset of participants enrolled in a prospective observational cohort study evaluating a decentralized antiretroviral therapy (ART) delivery program in South Africa. Questions assessed willingness to accept a future COVID-19 vaccine, concerns regarding COVID-19 vaccination, and overall vaccine confidence. Interviews were conducted between September 2020 and January 2021. We evaluated participant demographics, sources of COVID-19 information, stigma and medical mistrust, uptake of non-pharmaceutical interventions, and socioeconomic impacts of the COVID-19 pandemic as potential covariates of willingness to accept vaccination. Results We completed interviews with 213 participants; 153 (72%) were female, median age 35y, and 100 (47%) had completed secondary school. Among the participants, 121 (57%) were willing to accept future vaccination, 46 (22%) were unsure, and 45 (21%) stated they did not intend to be vaccinated. Fear of side effects, reported by 42 (20%), was the most common concern about COVID-19 vaccination. Older age was associated with willingness to accept vaccination (aOR 1.75 for every 10-year increase in age, 95% CI 1.10-2.78, p=0.02), while higher medical mistrust related to COVID-19 (aOR 0.21, 95% CI 0.093-0.45, p<0.001) and use of social media for COVID-19 information (aOR 0.30, 95% CI 0.11-0.84, p=0.02) were associated with lower willingness to accept vaccination. Conclusions In this cohort of PLWH in South Africa, over half were willing to accept COVID-19 vaccination, although a substantial proportion remained unsure or were not willing to be vaccinated. Public health messaging should emphasize the safety and efficacy of COVID-19 vaccination and address misinformation and medical mistrust among PLWH. Ongoing efforts to ensure access to COVID-19 vaccines for vulnerable populations are crucial.

No increased incidence of venous thrombosis or pulmonary embolism after SARS-CoV-2 vaccination in Germany

Objectives

Vaccination is one of the most effective measures to combat the COVID-19 pandemic. The main reason for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination hesitancy is the potential side-effects. This study aimed to investigate the incidence of venous thrombosis and pulmonary embolism in patients who received SARS-CoV-2 vaccination.

Study design

This was a retrospective cohort study.

Methods

Individuals aged ≥18 years who received an initial vaccination for COVID-19 in one of 1134 general practices in Germany between April and June 2021 were included in the study. Vaccinated patients were matched to unvaccinated individuals by age, sex, index month (April to June 2020 [unvaccinated cohort] or April to June 2021 [vaccinated cohort]) and diagnoses that may be associated with an increased incidence of thrombosis documented within 12 months before the index date. The incidences of thrombosis and non-fatal pulmonary embolism as a function of COVID-19 vaccination were analysed.

Results

The present study included 326,833 individuals who were vaccinated against COVID-19 and 326,833 matched unvaccinated individuals. During the follow-up period, 406 vaccinated patients and 342 individuals in the control group received a diagnosis of thrombosis or non-fatal pulmonary embolism. This resulted in an incidence rate of 11.9 vs 11.3 cases per 1000 patient-years for vaccinated vs unvaccinated individuals, respectively, and a non-significant overall incidence rate ratio (IRR: 1.06; 95% confidence interval [CI]: 0.93–1.22). The highest IRR was observed in the 41–60 years age group (IRR: 1.30; 95% CI: 0.98–1.73), and the lowest IRR was seen in the 18–40 years age group (IRR: 0.6; 95% CI: 0.0–1.05); however, none of the individual age group incidence rates was significant.

Conclusions

The results indicate that the occurrence of thrombosis or pulmonary embolism after COVID-19 vaccination is a coincidental finding rather than a consequence of vaccination.

The Effectiveness of a Diverse COVID-19 Vaccine Portfolio and Its Impact on the Persistence of Positivity and Length of Hospital Stays: The Veneto Region's Experience

The vaccination campaign for the Veneto region (northeastern Italy) started on 27 December 2020. As of early December 2021, 75.1% of the whole Veneto population has been fully vaccinated. Vaccine efficacy has been demonstrated in many clinical trials, but reports on real-world contexts are still necessary. We conducted a retrospective cohort study on 2,233,399 residents in the Veneto region to assess the reduction in the COVID-19 burden, taking different outcomes into consideration. First, we adopted a non-brand-specific approach borrowed from survival analysis to estimate the effectiveness of vaccination against SARS-CoV-2 in preventing infections, hospitalizations, and deaths. We used t-tests and multivariate regressions to examine vaccine impact on breakthrough infections, in terms of the persistence of positivity and the length of hospital stays. Evidence emerging from this study suggests that unvaccinated individuals are significantly more likely to become infected, need hospitalization, and are at a higher risk of death from COVID-19 than those given at least one dose of vaccine. Cox models indicate that the effectiveness of full vaccination is 88% against infection, 94% against hospitalization, and 95% against death. Multivariate regressions suggest that vaccination is significantly correlated with a shorter period of positivity and shorter hospital stays, with each step toward completion of the vaccination cycle coinciding with a reduction of 3.3 days in the persistence of positivity and 2.3 days in the length of hospital stay.