ABSTRACT
Children and adolescents generally experience mild COVID-19. However, those with underlying physical health conditions are at a significantly increased risk of severe disease. Here, we present a comprehensive analysis of antibody and cellular responses in adolescents with severe neuro-disabilities who received COVID-19 vaccination with either ChAdOx1 (n=6) or an mRNA vaccine (mRNA-1273, n=8, BNT162b2, n=1). Strong immune responses were observed after vaccination and antibody levels and neutralisation titres were both higher after two doses. Both measures were also higher after mRNA vaccination and were further enhanced by prior natural infection where one vaccine dose was sufficient to generate peak antibody response. Robust T-cell responses were generated after dual vaccination and were also higher following mRNA vaccination. Early T-cells were characterised by a dominant effector-memory CD4+ T-cell population with a type-1 cytokine signature with additional production of IL-10. Antibody levels were well-maintained for at least 3 months after vaccination and 3 of 4 donors showed measurable neutralisation titres against the Omicron variant. T-cell responses also remained robust, with generation of a central/stem cell memory pool and showed strong reactivity against Omicron spike. These data demonstrate that COVID-19 vaccines display strong immunogenicity in adolescents and that dual vaccination, or single vaccination following prior infection, generate higher immune responses than seen after natural infection and develop activity against Omicron. Initial evidence suggests that mRNA vaccination elicits stronger immune responses than adenoviral delivery, although the latter is also higher than seen in adult populations. COVID-19 vaccines are therefore highly immunogenic in high-risk adolescents and dual vaccination might be able to provide relative protection against the Omicron variant that is currently globally dominant.
Subject(s)
COVID-19 Vaccines , COVID-19 , 2019-nCoV Vaccine mRNA-1273 , Adolescent , Adult , Antibodies, Viral , BNT162 Vaccine , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , Child , Humans , RNA, Messenger , SARS-CoV-2 , Vaccination , Vaccines, Synthetic , mRNA VaccinesSubject(s)
COVID-19/epidemiology , COVID-19/prevention & control , Communicable Disease Control/organization & administration , Education, Medical/organization & administration , Otolaryngology/organization & administration , COVID-19/transmission , Education, Distance/organization & administration , Humans , Otolaryngology/education , Singapore/epidemiology , Telemedicine/organization & administrationABSTRACT
The COVID-19 pandemic has had a major impact in healthcare systems across the world, with many hospitals having to come up with protocols and measures to contain the spread of the virus. This affects various specialties' clinical practices in many ways. Since early 2020 in Singapore, the Department of Otorhinolaryngology at Tan Tock Seng Hospital had to rapidly adapt to this pandemic as we provided services to the main healthcare facility combating the virus in our country. We had to design new workflows and also remain flexible in view of the ever-changing situation. There are 6 important domains for an otolaryngology department or any clinical department in general to consider when making adjustments to their practices in an outbreak: (1) clinical work, (2) education, (3) research, (4) safety of patients and staff, (5) morale of medical staff and (6) pandemic frontline work. We hope that the sharing of our experiences and the lessons learnt will be useful for both our local and international colleagues.