Severe acute respiratory syndrome coronavirus-2 antibody response after Moderna vaccine booster on healthcare providers.

INTRODUCTION: As an endeavor to control SARS-CoV-2 infection, the Moderna vaccine booster was given to healthcare workers to prevent reinfection and reduce the risk of complications from COVID-19. A heterologous booster vaccine is also thought to provide better protection against the current SARS-CoV-2 variants of concern. However, research that evaluates the effectiveness of the Moderna vaccine booster and the resulting SARS-CoV-2 antibody concentration is needed. OBJECTIVE: To evaluate the concentration of SARS-CoV-2 antibodies after the Moderna vaccine booster and the severity of SARS-CoV-2 infection before and after the Moderna vaccine booster. RESULTS: A total of 93 healthcare providers who received Moderna vaccine booster were included in the study. Examination of antibody concentration 3 months after the booster showed an average concentration of 10081.65 U/mL. There was an increase in antibody concentration before the booster and 3 months after, from a median of 1.7 U/mL to 9540 U/mL. Every subject showed a statistically significant increment of antibody concentration 3 months after the booster (p < 0.01). Thirty-seven (39.8%) subjects received two doses of the Sinovac vaccine and were confirmed to have COVID-19 with the Delta variant. After the booster, 26 (28%) subjects were infected with the Omicron Variant. Among the subjects who received two doses of the Sinovac vaccine and were confirmed with COVID-19, 36 (30.1%) had mild symptoms, and 1 (1.1%) was asymptomatic. CONCLUSIONS: Heterologous Moderna vaccine booster effectively increases antibody response against SARS-CoV-2 variants and shows mild symptoms of COVID-19 infection.

N-Acetylcysteine for COVID-19: A Potential Adjuvant Therapy

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV2) infection or known as coronavirus disease 2019 (COVID-19) is a highly infectious disease that has been declared as a world pandemic by WHO. Although the majority of patients only experience mild symptoms, older patients and those with comorbidities are in the risk of falling into critically ill and even death. This is thought to correlate with systemic inflammatory response and oxidative stress imbalance. N-acetylcysteine (NAC) is recognized as a potent mucolytic, yet its lesser-known function as an antioxidant is a precursor of glutathione. Basic aspects and either in vivo or in vitro studies showed various mechanisms of NAC acting as a counterbalance in viral infections and its role in decreasing inflammation and oxidative stress. High-dose NAC is reported to be effective as an antioxidant in pneumonia, influenza, sepsis, and acute respiratory distress syndrome. Early evidence in COVID-19 patients showed that NAC could be beneficial. This review gives the scientific background in considering NAC as an adjuvant treatment for COVID-19.