COVID-19

Background: Changes in the vaccine advisory process in the United States have disrupted immunization guidance, which reinforces the need for independent evidence review to inform decisions regarding immunization for respiratory viruses during the 2025-2026 season.

Methods: We conducted a systematic review of U.S.-licensed immunizations against coronavirus disease 2019 (Covid-19), respiratory syncytial virus (RSV), and influenza. We searched databases on PubMed/MEDLINE, Embase, and Web of Science for updates of the most recent review by the Advisory Committee on Immunization Practices (ACIP) Evidence-to-Recommendations for each disease, which was performed during the 2023-2024 period. Outcomes included vaccine efficacy and effectiveness against hospitalization, other clinical end points, and safety.

Results: Of 17,263 identified references, 511 studies met the inclusion criteria. Covid-19 mRNA vaccines against the XBB.1.5 subvariant had pooled vaccine effectiveness against hospitalization of 46% (95% confidence interval [CI], 34 to 55; from cohort studies) and 50% (95% CI, 43 to 57; from case-control studies) among adults and 37% (95% CI, 29 to 44) among immunocompromised adults. In a case-control study, vaccines against the KP.2 subvariant showed an effectiveness of 68% (95% CI, 42 to 82). Maternal RSV vaccination (for infant protection), nirsevimab for infants, and RSV vaccines in adults who were 60 years of age or older showed vaccine effectiveness of 68% or more against hospitalization. Influenza vaccination had a pooled vaccine effectiveness of 48% (95% CI, 39 to 55) in adults between the ages of 18 and 64 years and 67% (95% CI, 58 to 75) in children against hospitalization. Safety profiles were consistent with previous evaluations. The diagnosis of myocarditis associated with Covid-19 vaccines occurred at rates of 1.3 to 3.1 per 100,000 doses in male adolescents, with lower risk associated with longer dosing intervals. The RSVpreF vaccine was associated with 18.2 excess cases of Guillain-Barré syndrome per million doses in older adults; a significant association with preterm birth was not observed when the vaccine was administered at 32 to 36 weeks' gestation.

Conclusions: Ongoing peer-reviewed evidence supports the safety and effectiveness of immunizations against Covid-19, RSV, and influenza during the 2025-2026 season. (Funded by the Center for Infectious Disease Research and Policy and the Alumbra Innovations Foundation.).

This JAMA Pediatrics Patient Page describes the symptoms of long COVID in children.

Objective: To evaluate the personal protective effects of wearing versus not wearing surgical face masks in public spaces on self-reported respiratory symptoms over a 14 day period.

Design: Pragmatic randomised superiority trial.

Setting: Norway.

Participants: 4647 adults aged ≥18 years: 2371 were assigned to the intervention arm and 2276 to the control arm.

Interventions: Participants in the intervention arm were assigned to wear a surgical face mask in public spaces (eg, shopping centres, streets, public transport) over a 14 day period (mask wearing at home or work was not mentioned). Participants in the control arm were assigned to not wear a surgical face mask in public places.

Main outcome measures: The primary outcome was self-reported respiratory symptoms consistent with a respiratory infection. Secondary outcomes included self-reported and registered covid-19 infection.

Results: Between 10 February 2023 and 27 April 2023, 4647 participants were randomised of whom 4575 (2788 women (60.9%); mean age 51.0 (standard deviation 15.0) years) were included in the intention-to-treat analysis: 2313 (50.6%) in the intervention arm and 2262 (49.4%) in the control arm. 163 events (8.9%) of self-reported symptoms consistent with respiratory infection were reported in the intervention arm and 239 (12.2%) in the control arm. The marginal odds ratio was 0.71 (95% confidence interval (CI) 0.58 to 0.87; P=0.001) favouring the face mask intervention. The absolute risk difference was -3.2% (95% CI -5.2% to -1.3%; P<0.001). No statistically significant effect was found on self- reported (marginal odds ratio 1.07, 95% CI 0.58 to 1.98; P=0.82) or registered covid-19 infection (effect estimate and 95% CI not estimable owing to lack of events in the intervention arm).

Conclusion: Wearing a surgical face mask in public spaces over 14 days reduces the risk of self-reported symptoms consistent with a respiratory infection, compared with not wearing a surgical face mask.

Trial registration: ClinicalTrials.gov NCT05690516.

A 43-year-old woman presented with a 1-year history of recurring symptoms of sudden onset of fatigue, palpitations, dyspnea, chest pain, lightheadedness, and nausea that were associated with standing and resolved with sitting. These symptoms began 1 month after mild COVID-19 infection. At presentation, while supine, blood pressure (BP) was 123/70 mm Hg and heart rate (HR) was 90/min; while seated, BP was 120/80 and HR was 93/min; after standing for 1 minute, BP was 124/80 and HR was 119/min. Physical examination results were normal. Oxygen saturation was 98% at rest while breathing room air. She had no oxygen desaturation during a 6-minute walk test but walked only 282 m (45% predicted). Complete blood cell count, morning cortisol, and thyrotropin blood levels were normal. Electrocardiogram (ECG), chest computed tomography, pulmonary function testing, methacholine challenge, bronchoscopy, echocardiography, and cardiac catheterization findings were normal. During tilt table testing, the patient experienced lightheadedness and nausea when moved from horizontal to the upright position. Results of the tilt table test are shown in the Table and Figure.