The high-dose vaccine was associated with a lower likelihood of elderly individuals exhibiting limited or absent immune responses (Odds Ratio: 0.59). Higher pre-vaccination titers were linked to better responses, while being male was associated with a higher likelihood of poor response.
The study found that repeat vaccinees were more likely to test positive for A(H3N2) despite vaccination, indicating a potential waning of vaccine effectiveness over time. However, it also suggests that prior vaccination may protect against clinical infection of the same subtype.
The vaccine conferred a 65% risk reduction in medically attended influenza, with an effectiveness of 65.1% against influenza overall, 58.2% for influenza A, and 77.6% for influenza B.
The study found that the integrated genetic distance of hemagglutinin (HA) and neuraminidase (NA) can explain up to 87.1% of variations in vaccine effectiveness for H3N2, leading to improved predictions of vaccine effectiveness before deployment.
20.6% of healthcare workers showed seroconversion, indicating a response to Influenza A infection, with a vaccine effectiveness of 22.6% on seroconversion.
Vaccine effectiveness against all influenza strains was reported to be 63% to 65% in children aged 2-17, 36% to 55% in adults aged 18-64, and 40% to 55% in adults aged 65 and over, indicating a significant protective effect across different age groups.
The vaccine showed an overall effectiveness of 36% against A(H3N2) for all ages, with higher effectiveness of 40% for individuals aged 6 months to 49 years, indicating some level of protection against outpatient visits due to influenza A(H3N2).
Individuals with lower pre-vaccination antibody levels experienced larger boosts in antibody levels post-vaccination, and this boost lasted longer. The study also validated the heuristic of a four-fold rise in titre for detecting seroconversion in specific populations.
Increased understanding of how personal and social network experiences affect vaccination decisions, leading to potential interventions that could enhance vaccination uptake.
Vaccination was associated with an increase in serum neutralizing antibodies to recent H1N1 strains in Taipei, indicating a positive immune response, while Baltimore showed higher preexisting immunity to circulating strains.
The study found that acceptance of the flu vaccine increased from 79.6% to 91.2% among previously eligible individuals, with 68.6% of newly eligible individuals also intending to receive the vaccine. This indicates a significant rise in vaccination rates, which is crucial for public health during the pandemic.
Increased acceptance of the seasonal influenza vaccine, with 56.3% of adults offered the vaccine in the 2021-22 season, particularly among those aged 50 and over, despite a slight decline in future intent to vaccinate.
The pilot study achieved a vaccination rate of 31.2% among enrolled children, with 59% of vaccinated children being non-Italian citizens. The saliva samples collected for ILI surveillance were adequate for viral testing, indicating the feasibility of the self-sampling method.
The SLIV program was associated with lower Oseltamivir prescriptions among school-aged children and reduced medically attended acute respiratory illness (MAARI) among adults aged 65 and older, indicating potential indirect benefits for older adults.
Positive outcomes include reduced severity of influenza symptoms, shorter recovery times, and decreased hospitalization rates among high-risk populations when antiviral treatments are administered early. Effective wastewater management can also reduce the risk of influenza transmission in communities.
Residents in the nudge group showed a higher likelihood of being vaccinated compared to the control group. The nudge was found to be very acceptable among residents, with no perceived reduction in their sense of control over vaccination decisions.
The study identified a range of enablers, including feeling protected from flu, receiving reminders to vaccinate, and encouragement from others, which could enhance vaccination compliance.
The study concluded that recipients of a COVID-19 vaccine were more likely to receive the seasonal influenza vaccine during the 2021-2022 season, indicating a potential positive correlation between the two vaccinations.
The study highlights the need for sex- and gender-inclusive policies in vaccination strategies, emphasizing that women reported more interruptions in daily routines and were more likely to seek self-treatment after vaccination.
The simulation model indicated that updating the H3N2 component of the vaccine could have averted 5,000-65,000 flu hospitalizations in certain seasons, demonstrating significant potential benefits from improved vaccine strain matching.