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Influenza With and Without Oseltamivir Treatment and Neuropsychiatric Events Among Children and Adolescents
Results are from a retrospective cohort study conducted in a population-based ambulatory setting during the 2016 to 2017 and 2019 to 2020 influenza seasons. Children aged 5 to 17 years enrolled in Tennessee Medicaid were for eligible for inclusion. Data analysis was completed from July 2023 to March 2025. Among 692,975 eligible children, a total of 692,295 children (median [IQR] age, 11 [7-14] years; 50.3% female) experienced 1,230 serious neuropsychiatric events (898 neurologic and 332 psychiatric) during 19 688,320 person-weeks of follow-up. Among the 151,401 influenza episodes, 66.7% (95% CI, 66.5%-67.0%) were dispensed oseltamivir (60.1% [95% CI, 59.6%-60.6%] among those at high risk for influenza complications). The most common events overall were mood disorders (36.3%) and suicidal or self-harm behaviors (34.2%). Compared with untreated influenza, event rates were lower during oseltamivir-treated influenza periods (I RR, 0.53; 95% CI, 0.33-0.88) and posttreatment periods (IRR, 0.42; 95% CI, 0.24-0.74). Subanalyses suggest that this finding is driven more by a reduction in neurologic events (IRR, 0.45; 95% CI, 0.25-0.82) than psychiatric events (IRR, 0.80; 95% CI, 0.34-1.88).
Effectiveness of the BNT162b2 and mRNA-1273 JN.1-adapted Vaccines against COVID-19-associated Hospitalisation and Death: A Danish, Nationwide, Register-based, Cohort Study
Investigators estimated vaccine effectiveness against COVID-19 hospitalisation and death. Of nearly 6 million people resident in Denmark on Oct 1, 2024, 1,247,315 were older than 65 years and 894,560 met inclusion criteria and were included in the study. Median age was 76 years (IQR 70–81); 484,735 (54·2%) of 894,560 people were female and 409,825 (45·8%) were male. Among those without JN.1 vaccination, 278 COVID-19 hospitalisations and 84 deaths were observed during 25·6 million person-days compared with 197 COVID-19 hospitalisations and 56 deaths observed during 62·9 million person-days in those vaccinated with BNT162b2 JN.1 and ten COVID-19 hospitalisations and one death observed during 9·2 million person-days in those vaccinated with mRNA-1273 JN.1. Vaccine effectiveness for BNT162b2 JN.1 was 70·2% (95% CI 62·0–76·6) against hospitalisation and 76·2% (63·4–84·5) against death.
Hospitalization for COVID-19 and Risk Factors for Severe Disease Among Children: 2022–2024
Using data from COVID-19-Associated Hospitalization Surveillance Network (COVID-NET) during October 1, 2022, to April 30, 2024, authors described demographic characteristics, underlying medical conditions, COVID-19 vaccination status, and clinical outcomes, including severe disease (intensive care unit admission, mechanical ventilation, extracorporeal membrane oxygenation, in-hospital death), of hospitalized children aged 6 months to 17 years residing in the COVID-NET catchment area with laboratory-confirmed SARS-CoV-2 infection. Of 2,490 children hospitalized for COVID-19, 1,114 (44.7%) were aged 6 to 23 months; 1,358 (54.1%) were male. 58.9% had at least one underlying condition while 41.1% or just under half had no underlying medical conditions. Only 3.8% were up to date with recommended COVID-19 vaccination. Among children aged 6 to 23 months, severe disease was associated with underlying chronic lung (adjusted risk ratio [aRR], 1.5; 95% CI, 1.2–1.8) and cardiovascular disease (aRR, 1.4; 95% CI, 1.1–1.7). Among children aged 2 years and older, severity was associated with chronic lung disease (aRR, 1.9; 95% CI, 1.5–2.3), diabetes (aRR, 1.5; 95% CI, 1.2–1.8), and neurologic disorders (aRR, 1.4; 95% CI, 1.2–1.6).
Metformin and Time to Sustained Recovery in Adults With COVID-19. The ACTIV-6 Randomized Clinical Trial
These are the results of a randomized clinical trial of 2,991 participants enrolled primarily during the JN-1 subvariant of COVID-19. The median time to sustained recovery was nine days (95% CI, 9-10) for metformin and 10 days (95% CI, 9-10) for placebo. No deaths were reported; 103 participants reported clinic visits, ED visits, or hospitalization: 54 in the metformin group and 49 in the placebo group (hazard ratio, 1.25; 95% CrI, 0.82-1.78; P for efficacy = .13). Seven participants who received metformin and three who received placebo experienced a serious adverse event over 180 days.
SARS-CoV-2 Rebound and Post-acute Mortality and Hospitalization among Patients Admitted with COVID-19: Cohort Study
Investigators examined the association of early virologic rebound with post-acute mortality and hospitalization due to post-acute sequelae among hospitalized patients with COVID-19 in Hong Kong. This study included 13,859 patients in total with 3,959 nirmatrelvir/ritonavir treated, and 4,502 molnupiravir treated. SARS-CoV-2 virologic rebound was defined as a decline in Ct value of at least three units between two consecutive Ct measurements, with such reduction persisting in at least one subsequent measurement. They report that patients who experienced virologic rebound exhibited a significantly higher risk of post-acute mortality (hazard ratio [HR], 1.52; 95% confidence interval [CI], 1.36–1.70) with a risk difference [RD] of 7.19%, compared with patients without virologic rebound.
When they looked at nirmatrelvir/ritonavir-treated treated patients they saw a similar increase in the risk of post-acute mortality (HR, 1.78; 95% CI, 1.41–2.25; RD, 12.55%) and in the molnupiravir-treated patients (HR, 1.47; 95% CI, 1.18–1.82; RD, 4.90%).
Effectiveness of COVID-19 vaccines against post COVID-19 condition/long COVID: systematic review and meta-analysis
Investigators performed a systematic review to evaluate vaccine efficacy/effectiveness (VE) of COVID-19 vaccines given prior to SARS-CoV-2-infection in preventing PCC or LC. Studies were identified in Embase, MEDLINE, PreView, COVID-19 L.OVE repository and Cochrane Library up to August 1, 2024. 6,423 records were screened and 65 non-randomized studies of interventions (NRSI) reporting adjusted estimates were included VE for ≥one vaccine dose against PCC was 41.0% (95% confidence interval (CI) 27.8%; 51.7%; 22 NRSI, certainty of evidence: low). VE after one, two or three doses versus unvaccinated was 19.1% (-119.4%; 70.2%, three NRSI). 43.2% (4.5%; 66.2%; four NRSI) and 70.0% (30.0%; 87.0%; one NRSI) Based on this data they concluded that COVID-19 vaccines may be moderately effective in preventing PCC/LC. VE may increase with number of vaccine doses administered.
Precision Symptom Phenotyping Identifies Early Clinical and Proteomic Predictors of Distinct COVID-19 Sequelae
This analysis included 1,988 SARS-CoV-2 positive U.S. Military Health System beneficiaries who had quantitative post–COVID symptom scores. Three symptom-based clusters were identified: a sensory cluster (loss of smell and/or taste), a fatigue/difficulty thinking cluster, and a difficulty breathing/exercise intolerance cluster. Individuals within the sensory cluster were all outpatients during their initial COVID-19 presentation. The difficulty breathing cluster had a higher likelihood of obesity and COVID-19 hospitalization than those with no/mild symptoms at 6 months post-infection. Multinomial regression linked early post-infection D-dimer and IL-1RA elevation to fatigue/difficulty thinking and elevated ICAM-1 concentrations to sensory symptoms.
Systemic and SARS-CoV-2-specific Immune Disturbances in Individuals with Post–COVID Syndrome
Investigators conducted detailed immunological analyses in 47 individuals with PCS, assessed >12 weeks after acute SARS-CoV-2 infection, and compared them with 25 convalescent controls without symptoms. They performed immune phenotyping of T- and B-cell subsets, assessed SARS-CoV-2–specific responses using activation-induced marker (AIM) flow cytometry for T cells, and tetramer staining of spike-specific B cells. Cytokine levels in peptide-stimulated cell supernatants and plasma were quantified using a Luminex platform. They found persistent immune disturbances in individuals with PCS are characterized by reduced SARS-CoV-2–specific T-cell responses, increased B-cell activation, and altered inflammatory and vascular biomarkers.
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