Efficacy and Safety of COVID-19 Vaccines-An Update

Mutational dynamics of SARS-CoV-2: Impact on future COVID-19 vaccine strategies

The rapid emergence of multiple strains of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has sparked profound concerns regarding the ongoing evolution of the virus and its potential impact on global health. Classified by the World Health Organization (WHO) as variants of concern (VOC), these strains exhibit heightened transmissibility and pathogenicity, posing significant challenges to existing vaccine strategies. Despite widespread vaccination efforts, the continual evolution of SARS-CoV-2 variants presents a formidable obstacle to achieving herd immunity. Of particular concern is the coronavirus spike (S) protein, a pivotal viral surface protein crucial for host cell entry and infectivity. Mutations within the S protein have been shown to enhance transmissibility and confer resistance to antibody-mediated neutralization, undermining the efficacy of traditional vaccine platforms. Moreover, the S protein undergoes rapid molecular evolution under selective immune pressure, leading to the emergence of diverse variants with distinct mutation profiles. This review underscores the urgent need for vigilance and adaptation in vaccine development efforts to combat the evolving landscape of SARS-CoV-2 mutations and ensure the long-term effectiveness of global immunization campaigns.

Comparing Molnupiravir to Nirmatrelvir/Ritonavir (Paxlovid) in the Treatment of Mild-to-Moderate COVID-19 in Immunocompromised Cancer Patients

BACKGROUND

Nirmatrelvir/Ritonavir has been shown to reduce the risk of COVID-19 progression by 88% compared to placebo, while Molnupiravir reduced it by 31%. However, these two agents have not been compared head-to-head. We therefore compared the safety and efficacy of both agents for the treatment of mild-to-moderate COVID-19 in immunocompromised cancer patients.

METHODS

We identified 240 cancer patients diagnosed with COVID-19 and treated with Molnupiravir or Nirmatrelvir/Ritonavir. Patients were matched using a 1:2 ratio based on age group (18-64 years vs. ≥65) and type of cancer. The collected data included demographics, comorbidities, and treatment outcome.

RESULTS

Both groups had comparable characteristics and presenting symptoms. However, dyspnea was more prevalent in the Molnupiravir group, while sore throat was more prevalent in the Nirmatrelvir/Ritonavir group. The rate of disease progression was comparable in both groups by univariate and multivariable analysis. Treatment with Molnupiravir versus Nirmatrelvir/Ritonavir revealed no significant difference in disease progression by multivariable analysis (adjusted OR = 1.31, 95% CI: 0.56-3.14, p = 0.70). Patients who received Nirmatrelvir/Ritonavir, however, were significantly more prone to having drug-drug interactions/adverse events (30% vs. 0%, p < 0.0001).

CONCLUSIONS

In the treatment of mild-to-moderate COVID-19 in cancer patients, Molnupiravir was comparable to Nirmatrelvir/Ritonavir in preventing progression to severe disease/death and rebound events, and it had a superior safety profile.

Real-world Effectiveness of Molnupiravir and Nirmatrelvir/Ritonavir as Treatments for COVID-19 in Patients at High Risk

BACKGROUND

Using a retrospective cohort study design, we aimed to evaluate the effectiveness of molnupiravir and nirmatrelvir/ritonavir in patients with SARS-CoV-2 who were highly vulnerable.

METHODS

The impact of each drug was determined via comparisons with age-matched control groups of patients positive for SARS-CoV-2 who did not receive oral antiviral therapy.

RESULTS

Administration of molnupiravir significantly reduced the risk of hospitalization (odds ratio [OR], 0.40; P < .001) and death (OR, 0.31; P < .001) among these patients based on data adjusted for age, previous SARS-CoV-2 infection, vaccination status, and time elapsed since the most recent vaccination. The reductions in risk were most profound among elderly patients (≥75 years old) and among those with high levels of drug adherence. Administration of nirmatrelvir/ritonavir also resulted in significant reductions in the risk of hospitalization (OR, 0.31; P < .001) and death (OR, 0.28; P < .001). Similar to molnupiravir, the impact of nirmatrelvir/ritonavir was more substantial among elderly patients and in those with high levels of drug adherence.

CONCLUSIONS

Collectively, these real-world findings suggest that although the risks of hospitalization and death due to COVID-19 have been reduced, antivirals can provide additional benefits to members of highly vulnerable patient populations.

Rare Case of Thygeson Superficial Punctate Keratitis After COVID-19 Vaccination

PURPOSE

The aim of this study was to elucidate a rare corneal association of the coronavirus disease 2019 (COVID-19) vaccine. Although cases of corneal involvement after vaccination have been reported, we present the first case of Thygeson superficial punctate keratitis (TSPK) linked to the COVID-19 vaccine.

METHODS

This study is a case report.

RESULTS

A 25-year-old woman was assessed in the ophthalmology clinic for recurrent ocular surface symptoms after receiving the COVID-19 vaccine. She was followed in clinic and was found to have a remitting and recurring pattern of bilateral intraepithelial corneal opacities with associated subepithelial haze primarily overlying the pupillary area. These corneal lesions responded well to topical corticosteroid ophthalmic drops. Based on the clinical appearance, the response to treatment, negative herpes simplex virus serology, and the temporal relationship between vaccination and ocular findings, a diagnosis of COVID-19 vaccine-induced TSPK was suspected.

CONCLUSIONS

Although the COVID-19 vaccine remains overwhelmingly safe, clinicians should be aware of possible corneal side effects, including TSPK. Prompt ophthalmic assessment in those presenting with ocular symptoms after vaccination is encouraged.

Evaluation of the Inhibition Potency of Nirmatrelvir against Main Protease Mutants of SARS-CoV-2 Variants

SARS-CoV-2 continues to pose a threat to public health. Main protease (Mpro) is one of the most lucrative drug targets for developing specific antivirals against SARS-CoV-2 infection. By targeting Mpro, peptidomimetic nirmatrelvir is able to inhibit viral replication of SARS-CoV-2 and reduce the risk for progression to severe COVID-19. However, multiple mutations in the gene encoding Mpro of emerging SARS-CoV-2 variants raise a concern of drug resistance. In the present study, we expressed 16 previously reported SARS-CoV-2 Mpro mutants (G15S, T25I, T45I, S46F, S46P, D48N, M49I, L50F, L89F, K90R, P132H, N142S, V186F, R188K, T190I, and A191V). We evaluated the inhibition potency of nirmatrelvir against these Mpro mutants and solved the crystal structures of representative Mpro mutants of SARS-CoV-2 bound to nirmatrelvir. Enzymatic inhibition assays revealed that these Mpro variants remain susceptible to nirmatrelvir as the wildtype. Detailed analysis and structural comparison provided the inhibition mechanism of Mpro mutants by nirmatrelvir. These results informed the ongoing genomic surveillance of drug resistance of emerging SARS-CoV-2 variants to nirmatrelvir and facilitate the development of next-generation anticoronavirus drugs.

COVID-19 Booster Dose Coverage and Hesitancy among Older Adults in an Urban Slum and Resettlement Colony in Delhi, India

BACKGROUND

The high prevalence of vaccine booster hesitancy, with the concomitant waning of humoral vaccine or hybrid immunity, and the emergence of SARS-CoV-2 variants of concern can accentuate COVID-19 morbidity and mortality. The study objective was to ascertain the COVID-19 vaccination coverage, including the administration of precaution (booster) dose vaccination, among the older population in an urban slum and resettlement colony population in Delhi, India.

METHODS

We conducted a cross-sectional survey in an urban resettlement colony, slum, and village cluster in the Northeast district of Delhi among residents aged ≥50 years.

RESULTS

A total of 2217 adults (58.28%) had obtained a COVID-19 booster (precaution) dose vaccine, 1404 (36.91%) had received two doses of a COVID-19 vaccine without booster dose, 121 (3.18%) were unvaccinated, while 62 (1.63%) participants received a single dose. Based on adjusted analysis, older adults (>65 years), higher education, and higher per-capita income were statistically significant predictors of booster dose vaccination.

CONCLUSIONS

More than four in ten adults in an urban slum and resettlement colony in Delhi lacked COVID-19 booster dose vaccination despite high rates of double-dose vaccination (~95%). Public health programming should provide an enhanced focus on reducing complacency with renewed prioritization for improving ease of access to COVID-19 vaccination services, particularly in underserved areas.

The Antiviral Effect of Nirmatrelvir/Ritonavir during COVID-19 Pandemic Real-World Data

INTRODUCTION

Vaccination against SARS-CoV-2 and the prevalence of Omicron variants have reduced the risk of the severe clinical progress of COVID-19. However, the risk of breakthrough infections has increased, and early administration of an effective antiviral treatment is significant in order to prevent the severe progression of COVID-19 in vulnerable patients with comorbidities.

PATIENTS AND METHODS

Adults with confirmed SARS-CoV-2 infection were included in a matched-pair retrospective study based on age, gender, comorbidities and vaccination status. They were divided into two groups: group A (n = 200) consisted of outpatients at increased risk of severe clinical progress who were treated with nirmatrelvir/ritonavir and group B (n = 200) consisted of non-hospitalized patients who did not receive antiviral treatment. Demographic data, clinical outcome (death, intubation), days of hospitalization, time for recovery, adverse events and treatment compliance were reported.

RESULTS

The median age (75.24 ± 13.12 years in the study group and 76.91 ± 14.02 years in the comparison group) and the proportion of males (59% vs. 60.5%, respectively) were similar between the two groups. A total of 6.5% of patients in group A and 10.5% in group B were unvaccinated against SARS-CoV-2. Three patients from group A (1.5%) and one hundred eleven (55.5%) from group B required hospitalization. The duration of hospitalization (3 days vs. 10 days in group B, p < 0.001) and the total time needed for recovery (5 days vs. 9 days, p < 0.001) was shorter in the study group. A rebound of SARS-CoV-2 infection within 8-12 days after diagnosis was documented in 6.5% of patients in group A and 8% of patients in group B.

CONCLUSION

Oral treatment with nirmatrelvir/ritonavir in high-risk non-hospitalized patients was safe and effective in preventing the severe clinical progress of COVID-19 pneumonia. Early administration of antiviral agents in vulnerable outpatients combined with a full vaccination scheme is significant in order to avoid hospitalization and severe clinical outcomes.

Effectiveness of Nutritional Supplements for Attenuating the Side Effects of SARS-CoV-2 Vaccines

Supplementation is known to enhance the immune response and reduce infection. Therefore, the association between immune nutrients and vaccine side effects needs to be investigated. Our aim was to analyze the relationship between vaccination side effects and supplement intake among the Italian population. The study included a questionnaire asking for personal data, anthropometric information, COVID-19 infection and immunity response, and COVID-19 vaccination and supplementation. The survey was conducted from 8 February to 15 June 2022. In the study, 776 respondents were included, aged between 18 and 86 (71.3% females). We observed a statistically significant correlation between supplement consumption and side effects at the end of the vaccination cycle (p = 0.000), which was also confirmed by logistic regression (p = 0.02). Significant associations were observed between supplement intake and side effects of diarrhea and nausea at the end of the vaccination cycle (p = 0.001; p = 0.04, respectively). Significant associations were observed between side effects and omega-3 and mineral supplementation at the start of the vaccination cycle (p = 0.02; p = 0.001, respectively), and between side effects and vitamin supplementation at the end of the vaccination cycle (p = 0.005). In conclusion, our study shows a positive impact of supplementation on vaccination response, increasing host immune defenses, and reducing side effects.

COVID-19: Where We Are and Where We Are Going

The impact of COVID-19 on global health has been colossal [...]

Health and Well-Being through COVID-19 Vaccination: Physical, Oral, and Psychological Effects

The Coronavirus Disease 2019 (COVID-19) pandemic and its evolving variants have spurred a worldwide effort to control its transmission and reduce its impact [...].

The Role of Conspiracy Theories, Perceived Risk, and Trust in Science on COVID-19 Vaccination Decisiveness: Evidence from Cyprus

COVID-19 reminded us of the importance of vaccinating for successfully overcoming health-related crises. Yet, vaccine hesitancy is still present. This study examined the impacts of conspiracy theories, perceived risk, and trust in science on COVID-19 vaccination decisiveness. The study was conducted at the end of the third wave of the pandemic, in July 2021, in Cyprus. Data were collected via an online self-administered anonymous survey using convenience and snowball sampling methods. Participants were 363 adults who completed a set of questionnaires that examined their believability in ten vaccine-related conspiracy theories, their perceived dangerousness of COVID-19, and their level of trust in science and scientists. The results suggest that (a) participants with a high conspiracy theory belief are less likely to be vaccinated, (b) participants who perceive COVID-19 as a dangerous disease are more likely to be vaccinated, and (c) participants with high trust in science are more likely to be vaccinated. The implications of the findings are discussed and can be used by public health officials in their campaigns.