Journal Article Recommendations
01
Immunogenicity and safety of live attenuated influenza vaccine in children aged 3–17 years in China
This article, published in Vaccine, provides the first study to evaluate of the immunogenicity and safety of live attenuated influenza vaccine (LAIV) in children aged 3 to 17 years in China. As an effective influenza prevention strategy, LAIV, compared to traditional inactivated influenza vaccines (IIV), induces humoral immunity and stimulates cellular immune responses. Although LAIV has been approved in China, studies on its immunogenicity in this specific age group remain scarce.
This is a substudy investigating the immunogenicity and safety of the LAIV under a Phase 3, multicentre, randomized, double-blind, placebo-controlled trial, enrolling a total of 3,000 children and adolescents aged 3–17 years, who were randomly assigned into vaccine and placebo groups (1,500 participants each). Immunogenicity was assessed through hemagglutination inhibition antibody titers (HI GMT), and safety was evaluated based on the incidence of adverse events (AEs). The vaccine group included 489, 488, and 481 participants analyzed for the immunogenicity of H1N1, H3N2, and influenza B viruses, respectively, while the placebo group included 491, 487, and 486 participants for the same analyses.
The results showed that, in terms of safety, 625 participants (41.7%) in the vaccine group and 591 participants (39.4%) in the placebo group experienced adverse events. The frequencies of nasal congestion (P = 0.032), headache (P = 0.045), and muscle pain (P = 0.047) were significantly higher in the vaccine group compared to the placebo group. Regarding immunogenicity, baseline HI GMT values for all influenza virus types were comparable between the vaccine and placebo groups. After vaccination, GMT values for all virus types were higher in the vaccine group than in the placebo group. The geometric mean fold increase (gMFI) values for vaccine-associated viral strains were also significantly higher in the vaccine group compared to the placebo group [H1N1: 1.450 (1.384–1.518) vs. 1.229 (1.186–1.916), P < 0.001; H3N2: 1.716 (1.602–1.840) vs. 1.391 (1.321–1.465), P < 0.001; B: 2.219 (2.065–2.384) vs. 1.225 (1.186–1.264), P < 0.001].
The study demonstrates that LAIV has good immunogenicity and safety in children and adolescents aged 3–17 years in China. These findings provide strong evidence supporting the use of LAIV as a key tool for influenza prevention in children and lay a scientific foundation for developing public health interventions targeting influenza.
https://doi.org/10.1016/j.vaccine.2024.126653
02
Preplanned Studies: Post-Marketing Surveillance of Adverse Events Following Meningococcal Vaccination — China, 2013–2021
This study, published in China CDC Weekly, analyzes data on adverse events following immunization (AEFI) for meningococcal vaccines (MenV) in China from 2013 to 2021. AEFIs were reported through the China National Immunization Information System (CNIIS).
Currently, meningococcal vaccines available in China include the Group A meningococcal polysaccharide vaccine (MPV-A), Group A and C meningococcal polysaccharide vaccine (MPV-AC), Group A and C meningococcal polysaccharide conjugate vaccine (MPCV-AC), Group A, C, Y, and W135 meningococcal polysaccharide vaccine (MPV-ACYW135), and the combined Group A and C meningococcal polysaccharide conjugate vaccine with Haemophilus influenzae type b vaccine (MPCV-AC/Hib).
From 2013 to 2021, a total of 65 million doses of these five meningococcal vaccine types were administered, with an overall AEFI reporting rate of 37.87 cases per 100,000 doses. Of these, 98.74% were classified as vaccine product-related reactions, with 94.85% being common reactions and 5.15% being rare reactions. The overall AEFI incidence was comparable to the period from 2010 to 2012. The AEFI reporting rates varied by vaccine type: MPV-A (45.82/100,000 doses), MPV-AC (22.98/100,000 doses), MPCV-AC (77.43/100,000 doses), MPV-ACYW135 (31.09/100,000 doses), and MPCV-AC/Hib (42.95/100,000 doses). The incidence of serious adverse events was extremely low.
The study also identified regional, age-related, and parental sensitivity differences in AEFI incidence. Specifically, eastern China had higher AEFI rates, while western regions had lower rates. Vaccines administered at younger ages, such as MPCV-AC given to infants as young as three months, were associated with higher AEFI rates. Overall, the AEFI rates for MPV-A and MPV-AC were below the World Health Organization’s (WHO) expected levels and lower than reports from related domestic and international studies.
The findings suggest that the AEFI incidence for meningococcal vaccines in China is very low, with severe adverse reactions being exceedingly rare. The study recommends continued technical training for vaccination personnel and the strengthening of on-site emergency response capabilities to ensure the safety of immunization programs.
https://doi.org/10.46234/ccdcw2024.263
03
Methods and Applications: Cost-Effectiveness Analysis of Vaccination Compliance Strategies Using a Novel Hybrid Model for Influenza Vaccination
This article, published in China CDC Weekly, aims to evaluate the cost-effectiveness of different influenza vaccination strategies, providing scientific evidence for public health systems to address influenza and other infectious diseases. The study uses a modeling approach to compare two vaccination strategies. The “Adherence Strategy” involves encouraging individuals who have previously been vaccinated to maintain their vaccination status through ongoing education, healthcare worker interventions, and financial incentives. The “Voluntary Vaccination Strategy” represents the current model implemented in most regions of China, where individuals voluntarily choose and pay for vaccination.
The research team developed an innovative hybrid model that combines continuous-time Agent-Based Models (ABMs) with Markov models to simulate individual-level vaccination behavior and disease transmission dynamics. The model considers variables such as socioeconomic factors, vaccine efficacy, and population interactions to assess the long-term health outcomes and associated costs of the two vaccination strategies. With the willingness-to-pay (WTP) threshold set at 85,698 CNY (equivalent to the national per capita GDP), the net monetary benefit (NMB) was estimated at 4,699 CNY, and the incremental cost-effectiveness ratio (ICER) per QALY was 33,847 CNY.
The study showed that the “Adherence Strategy” increased vaccination coverage by 133.8% compared to the “Voluntary Vaccination Strategy” and significantly reduced healthcare utilization, total infection rates, hospitalizations, and outpatient cases. Economic analysis revealed an incremental cost of 3,067 CNY per thousand people over five years and an incremental quality-adjusted life year (QALY) of 0.091. Long-term comparative analysis demonstrated that the “Adherence Strategy” was more cost-effective than the “Voluntary Vaccination Strategy.” When the WTP value exceeded the ICER (33,847 CNY), the “Adherence Strategy” exhibited a higher probability of cost-effectiveness.
The study concludes that implementing targeted influenza vaccination adherence strategies is supported and provides an innovative approach to enhancing public health interventions and improving the effectiveness of vaccination programs.
https://doi.org/10.46234/ccdcw2024.265
04
Estimated Vaccine Effectiveness for Respiratory Syncytial Virus–Related Lower Respiratory Tract Disease
This article, published in JAMA Network Open, evaluates the protective effectiveness of the respiratory syncytial virus pre-fusion F protein vaccine (RSVpreF) in preventing RSV-related hospitalizations and emergency department (ED) visits among older adults in the United States. The study addresses gaps in previous clinical trial data by providing real-world evidence, particularly for individuals aged 75 and older with comorbidities.
This was a retrospective case-control study with a test negative design. Cases were adults aged 60 years or older with hospitalizations or ED visits at Kaiser Permanente of Southern California for LRTD from November 24, 2023, to April 9, 2024, who had respiratory swabs collected and tested for RSV. Two control definitions were prespecified: (1) strict controls included RSV-negative LRTD events that were negative for human metapneumovirus, SARS-CoV-2, and influenza, and positive for a nonvaccine preventable cause (primary) and (2) broad controls included all RSV-negative LRTD events (sensitivity analysis). Enhanced specimen collection was conducted to salvage clinical respiratory swabs not tested for RSV during routine care. Data were analyzed from May to September 2024.
The study included 7,047 LRTD-related hospitalizations or ED visits, with an average patient age of 76.8 years. Of these, 54.2% were female, 93.3% had at least one chronic condition, and 14.2% were immunocompromised. In the analysis comparing cases to the strict control group (623 cases and 804 controls), the adjusted vaccine effectiveness (VE) of RSVpreF was 91% (95% CI: 59%-98%). When comparing cases to the broad control group (623 cases and 6,424 controls), the adjusted VE was 90% (95% CI: 59%-97%). Participants received RSVpreF a median of 58 days (range: 39-78 days) before the onset of LRTD. The estimated VE against severe LRTD-related hospitalizations and ED events was 89% (95% CI: 13%-99%).
The study demonstrates that RSVpreF provides significant protection among older adults in the United States, particularly those aged 75 and older with comorbidities, with no notable safety concerns identified.
https://doi.org/10.1001/jamanetworkopen.2024.50832
05
Cost-effectiveness analysis of 9-valent human papillomavirus vaccine combined with screening for cervical cancer in Japan
This article was published by International Journal of Gynecology & Obstetrics, and aims to investigate the cost-effectiveness of promoting the 9-valent HPV vaccine and cervical cancer screening in Japan.
The study utilized a yearly-cycle Markov model with 15 health states and evaluated four hypothetical scenarios. The first scenario involved a vaccination coverage of 30% and biennial screening coverage of 40%, representing the current situation in Japan. The second scenario assumed a vaccination coverage of 70% (reflecting the peak coverage rate in 2013) and biennial screening coverage of 40%. The third scenario considered a vaccination coverage of 90% and screening coverage of 40%, while the fourth scenario combined a vaccination coverage of 90% with a screening coverage of 70%. The incremental cost-effectiveness ratio (ICER) was calculated from the payer’s perspective in terms of cost per quality-adjusted life year (QALY) and compared against Japan’s willingness-to-pay threshold of 41,700 USD per QALY.
The study found that, compared to the first scenario, the ICERs for the second, third, and fourth scenarios were 5,382 USD, 5,321 USD, and 8,524 USD per QALY, respectively, all below the willingness-to-pay threshold. Higher vaccination and screening coverage rates were associated with reductions in the cumulative incidence and mortality rates of cervical cancer. Among the scenarios, the fourth, which involved 90% full vaccination of 12-year-old girls with the 9-valent HPV vaccine and 70% cervical cancer screening coverage for women aged 20-69, achieved the greatest health benefits. Although this scenario incurred the highest total costs, it significantly reduced the economic burden associated with late-stage cervical cancer treatment. A one-way deterministic sensitivity analysis indicated that HPV infection rates, the duration of vaccine efficacy, and the discount rate were the most influential factors affecting the ICER.
The study concludes that in Japan, achieving high coverage of 9-valent HPV vaccination combined with cervical cancer screening is cost-effective. Increasing cervical cancer screening coverage can effectively mitigate the diminishing returns associated with higher vaccination coverage.
https://doi.org/10.1002/ijgo.16125
Content editor: Xiaotong Yang
Page Editor: Ziqi Liu
