Breakthrough SARS-CoV-2 infections after vaccination: A critical review (preprint)

At the beginning of the current pandemic, it was believed that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection would induce lifelong immunity and that reinfections would be unlikely. However, after several cases of reinfection were documented in previously infected patients, this was understood to be a false assumption, and this waning humoral immunity has raised significant concerns. Accordingly, long-term and durable vaccine-induced antibody protection against infection have also become a challenge, as several breakthroughs of COVID-19 infection have been identified in individuals who were fully vaccinated. This review discusses the current evidence on breakthrough COVID-19 infections occurring after vaccination.

Myocarditis and Pericarditis Following the SARS-CoV-2 Infection and COVID-19 Vaccination (preprint)

Cardiac complications of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection have been well-identified since the beginning of the current coronavirus disease 2019 (COVID-19) pandemic. Such conditions can occur of various etiologies, such as respiratory failure and hypoxemia, direct cardiac tissue damage due to viral replication, indirect myocarditis as systemic inflammation, and the interaction of different medications. Recently, with the start of the COVID-19 vaccination programs, COVID-19 vaccine-associated cardiac adverse events (AEs) have emerged and are increasingly being reported. Although these AEs are usually mild and self-limited, they can sometimes cause severe, catastrophic outcomes. This review compares the pathophysiology, diagnosis, and treatment of the de novo SARS-CoV-2 infection-related and COVID-19 vaccine-related myocarditis and pericarditis.

Capillary Leak Syndrome after SARS-CoV-2 Infection and COVID-19 Vaccines: A Comparative Review (preprint)

Systemic capillary leak syndrome (SCLS) is an uncommon, potentially life-threatening disorder defined as recurrent attacks of pseudo-shock. This syndrome occurs due to the disruption of endothelial cells, which leads to increased vascular permeability, causing intravascular fluid to leak into the extravascular space and albumin to be retained in the interstitial space. SCLS can lead to hypovolemia, peripheral hypoperfusion, and acute renal insufficiency. The syndrome is presented with fever, generalized edema, pleural effusions, dyspnea, hypovolemia, hemoconcentration, prerenal azotemia, shock, and syncope. After ruling out other causes of hypovolemic shock, the diagnosis of SCLS can be considered on the presence of the classical triad of hypotension, hemoconcentration, and hypoalbuminemia. Eliminating the precipitating factors is the cornerstone of SCLS management. It is advisable to be very cautious and weigh the risks and benefits of vaccination of people with a history of this condition. This review will discuss and compare different aspects of SLCS after SARS-CoV-2 infection and COVID-19 vaccination.

Clinical misdiagnosis of influenza infection with a confusing clinical course: A case report (preprint)

Influenza A infection can mimic coronavirus disease 2019 (COVID-19) in case of their signs and symptoms, making it almost impossible to distinguish them clinically, necessitating using high-precision assays in such patients. Clinicians should be careful in treating such patients merely based on their unspecific manifestations.

SARS-CoV-2 Omicron (B.1.1.529) Variant: A Challenge with Covid-19 (preprint)

Since the beginning of the coronavirus disease 2019 (Covid-19) pandemic, there have been multiple peaks of the SARS-CoV-2 (severe acute respiratory syndrome coronavirus virus 2) infection, mainly due to the emergence of new variants, each with a new set of mutations in the viral genome, which have led to changes in the pathogenicity, transmissibility, and morbidity. The Omicron variant is the most recent variant of concern (VOC) to emerge and was recognized by the World Health Organization (WHO) on November 26, 2021. The Omicron lineage is phylogenetically distinct from earlier variants, including the previously dominant Delta SARS-CoV-2 variant. Previous research has reported the most common clinical manifestations of the Omicron variant to be fever, runny nose, sore throat, severe headache, and fatigue. The reverse transcription-polymerase chain reaction (RT-PCR) test, rapid antigen assays, and chest computed tomography (CT) scans can help diagnose those with the Omicron variant. Furthermore, many agents are expected to have therapeutic benefits for those infected with the Omicron variant, including TriSb92, molnupiravir, nirmatrelvir, and their combination, corticosteroids, and interleukin-6 (IL-6) receptor blockers. Despite being milder than previous variants, the Omicron variant threatens many lives, particularly among the unvaccinated, due to its higher transmissibility, pathogenicity, and infectivity. This review summarizes the essential features of the Omicron variant, including its history, genome, transmissibility, clinical manifestations, diagnosis, management, and the effectiveness of existing vaccines against this VOC.

COVID-19 vaccines breakthrough infection and adverse reactions in medical students: A nationwide survey in Iran (preprint)

Purpose This study aimed to investigate the rate of COVID-19 breakthrough infection and adverse events in medical students.Methods Iranian medical students receiving two doses of COVID-19 vaccines were included in this retrospective cohort study. The medical team gathered the demographic characteristics, comorbidities, type of vaccine, adverse events following vaccination, and history of COVID-19 infection data through a phone interview. The frequency of adverse events and breakthrough infection was stratified by vaccine type (ChAdOx1-S, Gam-COVID-Vac, and BIBP-CorV).Results A total of 3591 medical students enrolled in this study, of which 57.02% were females, with a mean age of 23.31 + 4.87. A PCR-confirmed and suspicious-for-COVID-19 breakthrough infection rate of 4.51% and 7.02% was detected, respectively. There was no significant relation between breakthrough infection and gender, BMI, blood groups, and comorbidities. However, there was a significant difference in breakthrough infection rate among different types of vaccines (P = 0.001) and history of COVID-19 infection (P = 0.001). A total of 16 participants were hospitalized for COVID-19 infection, and no severe infection or death was observed in the studied population.Conclusion Vaccination prevented severe COVID-19 infection, although a high breakthrough infection rate was evident among Iran medical students during the Delta variant’s peak. Vaccine effectiveness may be fragile during emerging new variants and in high-exposure settings. Moreover, adverse events are rare, and the benefits of vaccination outweigh the side effects. However, many limitations challenged this study, and the results should be cautious.

Rare adverse events following Covid-19 vaccination: A review (preprint)

Although severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has caused many complications, the invention of coronavirus disease 2019 (Covid-19) vaccines has also brought about several adverse events, from common side effects to unexpected and rare ones. Common vaccine-related adverse reactions manifest locally or systematically following any vaccine, including Covid-19 vaccines. Certain side effects, known as adverse events of special interest (AESI), are unusual and need more evaluation. Here, we discuss some of the most important rare adverse events of Covid-19 vaccines.

Fulminant Hepatitis following COVID-19 Vaccination: A case report (preprint)

The side effects of COVID-19 vaccination were mostly self-restricted local reactions that quickly resolved. Nevertheless, rare autoimmune hepatitis cases have been reported in some vaccinated individuals. This article presents a young man who developed fulminant hepatitis a few days after vaccination with the first dose of the AstraZeneca COVID-19 vaccine.

COVID-19 vaccine-related new-onset lichen planus (preprint)

Coronavirus disease 2019 (COVID-19) vaccines had a great impact on world health and well-being. However, various adverse events have been observed following COVID-19 vaccination. Cutaneous reactions have been prevalent following many vaccines, including COVID-19 vaccines. Here, we present a case of new-onset lichen planus in a COVID-19 patient.

Hydroxychloroquine and azithromycin: As a double edge sword for COVID-19? (preprint)

BackgroundHydroxychloroquine with or without azithromycin was one of the common therapies at the beginning of the COVID-19 pandemic. They can prolong QT interval, cause Torsade de pointes, and lead to sudden cardiac death. We aimed to assess QT interval prolongation and its risk factors in patients who received hydroxychloroquine with or without azithromycin. MethodsThis was a retrospective cohort study. 172 patients with COVID-19 included, hospitalized at hospitals of Babol University of Medical Sciences between March 5, 2020, and April 3, 2020. Patients were divided into two groups: hydroxychloroquine alone and hydroxychloroquine with azithromycin. Electrocardiograms were used for outcome assessment. Results83.1% of patients received hydroxychloroquine plus azithromycin vs 16.9% of patients who received only hydroxychloroquine. The mean age of patients was 59.2 {+/-} 15.4. The mean of post-treatment QTc interval in the monotherapy group was shorter than the mean of post-treatment QTc interval in the combination therapy group but it had no significant statistical difference (462.5 {+/-} 43.1 milliseconds vs 464.3 {+/-} 59.1 milliseconds; P = 0.488). Generally, 22.1% of patients had a prolonged QTc interval after treatment. Male gender, or baseline QTc [≥] 450 milliseconds, or high-risk Tisdale score increased the likelihood of prolonged QTc interval. Due to QTc prolongation, 14 patients did not continue therapy after 4 days. ConclusionHospitalized patients treated with hydroxychloroquine with or without azithromycin, had no significant difference in prolongation of QT interval and outcome. But the number of patients with prolonged QT intervals in this study emphasizes careful cardiac monitoring during therapy; especially in high-risk patients.