COVID-19

Overview

Coronavirus Disease 2019 (COVID-19) is an infectious disease caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), a betacoronavirus first identified in late 2019 that rapidly evolved into a global pandemic. The virus primarily spreads through respiratory aerosols and droplets, with airborne transmission through indoor ventilation systems documented as an additional route of concern. SARS-CoV-2 gains cellular entry by binding its spike protein to the angiotensin-converting enzyme 2 (ACE2) receptor, triggering a cascade of host immune responses involving interferons, interleukin-6, C-reactive protein, and other inflammatory mediators. Severe disease is characterized by dysregulated immune activation, coagulopathy, and multi-organ involvement, with circulating SARS-CoV-2 viremia—reflected in detectable RNA levels—strongly associated with mortality. The pandemic caused unprecedented global morbidity and mortality, strained healthcare systems worldwide, and accelerated transformative advances in vaccine technology, antiviral therapeutics, and clinical trial methodology.

Beyond acute illness, COVID-19 has had far-reaching secondary effects on global health systems, infectious disease epidemiology, and healthcare delivery. These include disruptions to cancer care, antiretroviral therapy programs, surgical services, and mental health interventions, while simultaneously catalyzing rapid adoption of telemedicine and digital health platforms. The disease disproportionately affects immunocompromised individuals—including those with multiple myeloma, patients receiving chimeric antigen receptor T cell therapy, and solid organ transplant recipients—as well as older adults, pregnant women, and populations with chronic comorbidities such as chronic renal insufficiency.

Focus of Latest Publications

Recent research has concentrated on understanding the immunological responses to SARS-CoV-2 vaccination across diverse populations and vaccine formulations. Studies examined T-cell and B-cell responses following mRNA vaccination in children with Down syndrome, revealing age-dependent differences in cellular immunity alongside previously documented antibody responses, with younger children showing reduced CD4+ T-cell reactivation that may warrant adjusted dosing strategies. Mechanistic investigations identified critical roles for specific glycosylation sites—particularly N343—on the receptor-binding domain in modulating antibody titers and T-helper cell responses in preclinical models. Research on vaccine safety documented stable autoantibody profiles 26 weeks after heterologous vaccination (inactivated-primed, mRNA-boosted), with no evidence of sustained autoimmune or cancer-related autoantibodies. Novel vaccine platforms, including intranasal Ad5-vectored vectors producing self-assembling virus-like particles, demonstrated capacity to elicit mucosal secretory IgA and cross-neutralizing antibodies against multiple SARS-CoV-2 variants in addition to providing protection against influenza.

Therapeutic development efforts focused on both viral-targeted and host-directed strategies. Novel thiazole-based peptidomimetic compounds achieved potency comparable to nirmatrelvir against the SARS-CoV-2 main protease, with lead compounds showing strong antiviral activity in cell culture without cytotoxicity. Host-directed approaches targeting dihydroorotate dehydrogenase (DHODH) yielded optimized derivatives of vidofludimus with enhanced inhibition and broad-spectrum antiviral activity against multiple virus families at nanomolar potency. Monoclonal antibody therapeutics evolved with development of a humanized VHH-Fc construct (rimteravimab) targeting the spike receptor-binding domain for treatment of mild-to-moderate disease, and exploration of mRNA lipid nanoparticle platforms for in vivo antibody production, though anti-drug antibody responses reduced protective efficacy against Omicron BA.1 infection. Real-world evidence from Saudi Arabia characterized healthcare resource utilization patterns in patients receiving nirmatrelvir/ritonavir, while studies in chronic kidney disease populations assessed intervention efficacy in this vulnerable group.

Clinical and epidemiological studies identified key risk factors and protective factors in diverse populations. In the Omicron era, postacute sequelae risk was elevated with older age, female sex, higher BMI, and severe acute infection, while recent vaccination was associated with lower risk and severity—notably, antiviral therapy did not reduce postacute sequelae. Pediatric Long COVID investigations revealed dissociation between anti-SARS-CoV-2 antibody magnitude and post-viral airway hyperresponsiveness, suggesting distinct immunological mechanisms underlying chronic cough symptoms. Vaccination effectiveness studies demonstrated that JN.1-adapted vaccines provided protection against medically attended infection and hospitalization, while time-of-day vaccination (morning versus afternoon) enhanced antibody responses to mRNA vaccines in males but not females, and was ineffective for protein-based vaccines. In cancer patients, long-term survival outcomes following SARS-CoV-2 infection and vaccination remain incompletely characterized relative to interactions with systemic anticancer therapies.

Diagnostic and surveillance methodologies advanced to enable rapid pathogen detection and environmental monitoring. A novel amplification-free platform utilizing streptavidin-functionalized quantum dot microspheres achieved limits of detection in the sub-picomolar range for SARS-CoV-2 nucleic acids, with 100% sensitivity and 80–100% specificity in clinical samples, and a microgel array digital PCR platform demonstrated high accuracy in absolute quantification with rapid turnaround (<1 hour). Environmental surveillance via targeted metatranscriptomic detection of floor swabs in an emergency department successfully tracked SARS-CoV-2 variant shifts matching concurrent provincial epidemiology, with modest correspondence between sequencing read depth and clinical burden. Investigation of an outbreak in a residential building identified bathroom ventilation ducts as a plausible airborne transmission route, with computational modeling and epidemiological data indicating vertical disease transmission facilitated by shared duct systems, and kitchen exhaust operation amplifying aerosol movement between occupied spaces.

Key Publications

• NEWJun Serological Profiling and Neuro-Immune Resilience: The Dissociation Between Anti-SARS-CoV-2 Antibodies and Post-Viral Airway Hyperresponsiveness in Pediatric Asthma. (Lung, 2026, PMID 42337098): "We investigated the neuro-immune axis in pediatric asthma to determine if the magnitude of post-SARS-CoV-2 humoral immunity correlates with objective airway afferent nerve hypersensitivity."
• Jun DHODH Inhibitors Based on the Vidofludimus Scaffold Containing Carboxylic Acid Bioisosteres Exert a Superior Broad-Spectrum Antiviral Activity. (Journal of medicinal chemistry, 2026, PMID 42233404): "Optimized compounds also showed broad-spectrum antiviral activity against enveloped and nonenveloped DNA and RNA viruses and a retrovirus, with single-digit nanomolar potency and no detectable cytotoxicity."
• Dec T-cell responses to primary SARS-CoV-2 vaccination in Down syndrome - From childhood to adulthood. (Human vaccines & immunotherapeutics, 2026, PMID 42223472): "We evaluated vaccine-induced T-cell responses in children with DS following primary mRNA SARS-CoV-2 vaccination."
• Jun Self-reported vaccine uptake across six infectious diseases among gay, bisexual, transgender, and non-binary individuals in Australia: findings from a 2024 national survey. (Sexual health, 2026, PMID 42219251): "Understanding differences in uptake between selective (e.g. hepatitis A; meningococcal; human papillomavirus; HPV; mpox) and universal (e.g. influenza, COVID-19) is important for informing future immunisation policy and strategies."
• May Characterization of the VHH-Fc construct rimteravimab in healthy adults and patients hospitalized for mild-to-moderate COVID-19: Two Phase 1 randomized clinical trials. (PLoS medicine, 2026, PMID 42213671): "Rimteravimab (referred to here as XVR011) is a humanized antibody developed for the treatment of mild-to-moderate coronavirus disease 2019 (COVID-19), consisting of two identical VHHs targeting the receptor binding domain (RBD) of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike, with a human immunoglobulin (Ig) G1 fragment constant of antibody (Fc), silenced for Fc effector functions."
• May Design, Synthesis, and Evaluation of Novel Thiazole-Based Peptidomimetic Compounds as Potent SARS-CoV-2 Main Protease Covalent Inhibitors. (ACS infectious diseases, 2026, PMID 42160697): "The main protease (Mpro) of SARS-CoV-2, essential for the replication of the virus, is a critical target for antiviral drug development."
• May Patient Characteristics and Healthcare Resource Use among Patients With COVID-19 Receiving Treatment with Nirmatrelvir/Ritonavir (PAXLOVID™) in the Kingdom of Saudi Arabia. (Pulmonary therapy, 2026, PMID 42156669): "This study aimed to describe the demographic and clinical characteristics, treatment patterns, and healthcare resource utilization (HCRU) of adult patients with coronavirus disease 2019 (COVID-19) prescribed nirmatrelvir/ritonavir in the KSA."
• May Interventions for treating COVID-19 in people with chronic kidney disease. (The Cochrane database of systematic reviews, 2026, PMID 42145268): "To assess the benefits and harms of interventions for treating coronavirus disease 2019 (COVID-19) in people with all chronic kidney disease (CKD) stages, including those undergoing dialysis and kidney transplant recipients."
• May Beyond seeking information: Lessons learned from a qualitative investigation of the information practices of parents about COVID-19 vaccination in Canada. (Human vaccines & immunotherapeutics, 2026, PMID 42133643): "...decide on COVID-19 vaccination for their children."
• May Modeling the potential public health and economic impact and cost-effectiveness of vaccination strategies using an adapted COVID-19 vaccine in Guatemala. (Expert review of vaccines, 2026, PMID 42133835): "Using adapted COVID-19 vaccines targeting current variants in circulation is necessary for addressing the dynamic evolution of the SARS-CoV-2 virus."