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Influenza Vaccine Effectiveness Among Children With and Without Underlying Conditions
Researchers enrolled U.S. children aged 6 months to 17 years at seven pediatric medical centers within the New Vaccine Surveillance Network during five influenza seasons (2015–2020). Influenza status was confirmed by molecular testing and vaccination status was verified using state immunization registries or from health care clinicians. Of the 15,875 children included, 2,821 (18%) tested positive for influenza. Overall, VE against influenza-associated emergency department visits or hospitalizations was 43% (95% CI: 35%-50%) for children with underlying conditions and 53% (95% CI: 47%-59%) for those without, and there was significant effect measure modification by the presence of underlying conditions (P = .04). VE was lowest among children with respiratory conditions (31%, 95% CI: 19%-42%).
Influenza Antiviral Use in Hospitalized Children Before and During the COVID-19 Pandemic
These results come from active surveillance among U.S. children with acute respiratory illness at seven sites in the New Vaccine Surveillance Network before the COVID-19 pandemic (December 1, 2016 to March 31, 2020) and during the late pandemic period (July 1, 2021 to June 30, 2023). They reported that among 1,560 children hospitalized with influenza, antiviral use ranged between 48.3% and 56.8% prepandemic but declined to 38.1% in 2021 to 2022. They saw this increase to 46.1% in 2022 to 2023.
Effectiveness and Durability of the BNT162b2 KP.2 Vaccine against COVID-19 Hospitalization and Emergency Department or Urgent Care Encounters in U.S. Adults
Vaccine effectiveness (VE) of BNT162b2 KP.2 vaccine against COVID-19 hospital admissions was 49% [95%CI:30–63]) and 45% (95%CI:35–54) against ED/UC encounters (versus no KP.2 vaccine at <3 months). Protection persisted >90 days from vaccination with some waning.
Association of Nirmatrelvir-ritonavir with Intubation or Mortality Risks in Severe COVID-19 Patients: A Comparative Study
These are the results of analysis of a retrospective cohort from the First Affiliated Hospital of Xiamen University, ranging from December 15, 2022 to February 15, 2023. They examined the association between the use of nirmatrelvir-ritonavir (NMVr) and the risk of intubation or in-hospital mortality among severe COVID-19 patients using real-world data. A total of 1,436 consecutive patients with COVID-19 were included. 265 patients were included in the final analysis, of whom 169 received the treatment of NMVr and 96 did not. The application of NMVr was significantly associated with a reduced risk of the composite endpoint after adjustment (HR, 0.58; 95% CI, 0.35 to 0.97; P = 0.0374). The results were robust to various sensitivity analyses. Study suggests a 42% reduction in risk of ending up on a ventilator or dying.
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