Eurosurveillance - Volume 29, Issue 50, 12 December 2024

During the 2023/24 influenza season in the European Union/European Economic Area (EU/EEA), influenza viruses A(H1N1)pdm09, A(H3N2) and B/Victoria viruses were co-circulating.

We aimed to describe the circulating influenza viruses by (sub)type, genetic clade, antigenic group and antiviral susceptibility in that season in the EU/EEA.

We collected surveillance data from EU/EEA countries through weekly submissions to The European Surveillance System (TESSy). Data were submitted in strain-based format for weeks 40/2023 to 9/2024.

Twenty-nine EU/EEA countries reported 154,718 influenza virus detections (primary care sentinel and non-sentinel combined), of which 97% (150,692) were type A and 3% (4,026) were type B. Of the subtyped influenza A viruses, 30,463 (75%) were influenza A(H1)pdm09 and 10,174 (25%) were influenza A(H3). For 809 (20%) of the type B viruses, the lineage was determined; all were B/Victoria/2/87 lineage, and none were B/Yamagata/16/88 lineage. Genetic diversification of seasonal influenza viruses continued, and clade 5a.2a of A(H1N1)pdm09, 2a.3a.1 of A(H3N2) and V1A.3a.2 of B/Victoria-lineage viruses dominated. Of the A(H3N2) 2a.3a.1 viruses, 23% were antigenically distinct from the 2023/24 vaccine virus.

The 2023/24 influenza season was characterised by co-circulation of different influenza (sub)types, antigenically similar to the components recommended for the 2023/24 northern hemisphere vaccine, A/Victoria/4897/2022 (egg-based) and A/Wisconsin/67/2022 (cell culture- or recombinant-based). However, genetic diversification of the viruses continued. The World Health Organization’s vaccine recommendations for the northern hemisphere 2024/25 season were updated to include a new A(H3N2) component, while maintaining the current A(H1N1)pdm09 and B/Victoria components.

Nuvaxovid became available in Australia from February 2022, a year after the first COVID-19 vaccines. This protein-based vaccine was an alternative for people who had had an adverse event to and/or were hesitant to receive an mRNA or adenovirus-based COVID-19 vaccine. Although safety from clinical trials was reassuring, small trial populations, low administration rates and limited post-licensure intelligence meant potential rare adverse events were underinformed.

We aimed to describe Nuvaxovid’s safety profile in a real-world setting.

We conducted a retrospective observational analysis of adverse events following immunisation (AEFI) spontaneously reported to SAFEVAC, the integrated vaccine safety surveillance system in Victoria and Western Australia. Reports from 14 February 2022 to 30 June 2023 were analysed by vaccinee demographics, reported reactions and COVID-19 vaccine dose, and compared as reporting rates (RR) per 100,000 doses administered.

We received 356 AEFI reports, following 102,946 Nuvaxovid doses administered. Rates were higher after dose 1 than dose 2 (rate ratio: 1.5, p = 0.0008), primary series than booster (rate ratio: 2.4, p < 0.0001), and in females vs males (rate ratio: 1.4, p = 0.004). Clinically confirmed serious AEFI included 94 cases of chest pain (RR = 91.3), two myocarditis (RR = 1.9) and 20 pericarditis (RR = 19.4). Guillain–Barré syndrome or thrombosis with thrombocytopaenia syndromes were not reported, nor deaths attributable to vaccination.

SAFEVAC’s collaborative data model enabled pooling of clinically reviewed data across jurisdictions, increasing the safety profile evidence for Nuvaxovid and improving the odds for identification and description of rare events. This analysis affirmed the safety profile of Nuvaxovid.

Within the International Health Regulations framework, the French High Council for Public Health was mandated in 2022 by health authorities to establish a list of priority infectious diseases for public health, surveillance and research in mainland and overseas France.

Our objective was to establish this list.

A multi-criteria decision analysis was used, as recommended by the European Centre for Disease Prevention and Control. A list of 95 entities (infectious diseases or groups of these, including the World Health Organization (WHO)-labelled ‘Disease X’) was established by 17 infectious disease experts. Ten criteria were defined to score entities: incidence rate, case fatality rate, potential for emergence and spread, impact on the individual, on society, on socially vulnerable groups, on the healthcare system, and need for new preventive tools, new curative therapies, and surveillance. Each criterion was assigned a relative weight by 77 multidisciplinary experts. For each entity, 98 physicians from various specialties rated each criterion against the entity, using a four-class Likert-type scale; the ratings were converted into numeric values with a nonlinear scale and respectively weighted to calculate the entity score.

Fifteen entities were ranked as high-priorities, including Disease X and 14 known pathologies (e.g. haemorrhagic fevers, various respiratory viral infections, arboviral infections, multidrug-resistant bacterial infections, invasive meningococcal and pneumococcal diseases, prion diseases, rabies, and tuberculosis).

The priority entities agreed with those of the WHO in 2023; almost all were currently covered by the French surveillance and alert system. Repeating this analysis periodically would keep the list updated.

The COVID-19 pandemic resulted in increased mortality directly and indirectly associated with COVID-19.

To assess the impact of the COVID-19 pandemic on all-cause and disease-specific mortality and explore potential health inequalities associated with area-level deprivation in Wales.

Two population-based cohort studies were derived from multi-sourced, linked demographic, administrative and electronic health record data from 2016 to 2019 (n = 3,113,319) and 2020 to 2022 (n = 3,571,471). Data were analysed using generalised linear models adjusting for age, sex, area-level deprivation and time at risk.

COVID-19 deaths peaked in January 2021 (54.9/100,000 person-months, 95% confidence interval (CI): 52.4–57.5). The pandemic indirectly affected deaths, with higher than expected maximum relative mortality rates (RR) related to cancer (RR: 1.24, 95% CI: 1.13–1.36), infectious diseases (excluding respiratory infections) (RR: 2.09, 95% CI: 1.27– 3.43), circulatory system (RR: 1.41, 95% CI: 1.28–1.56), trauma (RR: 2.04, 95% CI: 1.57– 2.65), digestive system (RR: 1.54, 95% CI: 1.25–1.91), nervous system (RR: 1.63; 95% CI: 1.34–2.00) and mental and behavioural disorders (RR: 1.85, 95% CI: 1.58–2.16). Mortality associated with respiratory diseases (unrelated to COVID-19) were lower than expected (minimum RR: 0.52, 95% CI: 0.45–0.60). All-cause mortality was lower in least deprived communities compared with most deprived (RR: 0.61, 95% CI: 0.60–0.62), and the magnitude of this effect increased during the pandemic.

All-cause and disease-specific mortality directly and indirectly associated with COVID-19 increased during the COVID-19 pandemic. Socioeconomic disparities were exacerbated during this time.