Comment 1 www.thelancet.com/infection Published online April 17, 2026 https://doi.org/10.1016/S1473-3099(26)00192-1 Does BA.3.2 epidemiology imply a change in SARS-CoV-2 evolution? The international public health emergency associated with the COVID-19 pandemic was declared over by WHO on May 5, 2023. However, SARS-CoV-2 continued to circulate at high levels after 2023, and the constant emergence of new variants has been driving new COVID-19 waves every year since then. In the second half of 2025, the variants XFG and NB.1.8.1 attained high global frequencies. 1 BA.3.2, an emerging saltation variant evolving several subvariants (appendix pp 6–8) started to spread widely in Europe and Australia in the second half of 2025, suggesting that this variant will rapidly replace XFG and NB.1.8.1 at the global level. 2 BA.3.2 was first detected in South Africa in November, 2024, and although this variant has continued to spread in Africa throughout 2025 and into 2026, so far, it has not attained dominance (appendix p 2). From October, 2025, onwards, BA.3.2 started to spread efficiently in Australia and Europe. High frequencies were attained, for example, in Australia (New South Wales, specifically), Scotland, Northern Ireland, England, and Ireland, whereas only small numbers of infections have so far been detected in the USA (appendix p 2). The spread of BA.3.2 has been characterised by several unusual features. First, almost universally, an increase in BA.3.2 frequency has resulted in a corresponding decrease in the frequency of XFG but not of NB.1.8.1 at the national level (appendix p 2). Second, there has been marked variation in the spread of BA.3.2 in different regions. For instance, an increase in BA.3.2 frequency in Germany in December, 2025, was followed by a decline in January, 2026, and subsequent low-level circulation (appendix p 2). In contrast, BA.3.2 frequencies repeatedly exceeding 50% were detected in January, February, and March, 2026, in England, Northern Ireland, Scotland, and other European countries (appendix p 2). Analysis of the age distribution of infected individuals showed that compared with NB.1.8.1 or XFG, BA.3.2 targeted young individuals with markedly higher efficiency (appendix pp 2, 9). This tendency was seen in most countries with donor age available in the Global Initiative on Sharing All Influenza Data database 3 and was particularly pronounced for Luxembourg, Slovenia, France, and Ireland (appendix p 2). In most countries analysed, BA.3.2 spread was not associated with a new wave of COVID-19. However, notably, Public Health Scotland noted a marked increase in COVID-19 incidence in children aged 1–4 years and 5–14 years but not in other age groups in February, 2026, paralleled by increased hospital admissions due to COVID-19 in children aged 1–4 years. 4 At the same time, a marked uptick of positivity for SARS-CoV-2 was reported in children aged 0–4 years and 5–14 years in England, whereas this trend was not seen in other age groups. 5 The epidemiological characteristics of BA.3.2 are unusual in several respects. First, the observation that BA.3.2 displaces XFG but not NB.1.8.1 could indicate that BA.3.2 and XFG target the same immunological niche—ie, patients with similar antibody profiles. Second, despite this apparent limitation in the competitive fitness of BA.3.2, no alternative lineage has consistently displaced XFG or NB.1.8.1 at the global level. Third, in very young individuals, BA.3.2 is detected with higher relative frequency than either NB.1.8.1 or XFG. We hypothesise that this characteristic might reflect either BA.3.2’s adaptation to the age-dependent availability of host factors or enhanced immune evasion in children relative to adults. Fourth, although BA.3.2 reached high frequencies in several countries, its spread was generally not associated with epidemic COVID-19 waves across all age groups, suggesting that BA.3.2 might lack the transmissibility and/or immune escape capacity that characterised previously dominant variants. Collectively, these findings support the notion that increasingly complex population immunity could constitute a substantial barrier to the emergence of new globally dominant variants. What might be the consequences of such a development? Prolonged co-circulation of multiple lineages might signal a transition towards endemicity, with large, synchronised global waves giving way to more localised and intermittent outbreaks, potentially resulting in a long-term decline in annual cases of COVID-19 and long COVID. However, new challenges for public health could also arise. The preference of See Online for appendix Lancet Infect Dis 2026 Published Online April 17, 2026 https://doi.org/10.1016/ S1473-3099(26)00192-1 Comment 2 www.thelancet.com/infection Published online April 17, 2026 https://doi.org/10.1016/S1473-3099(26)00192-1 assist with grammar and style corrections. After using this tool, the authors reviewed and edited the content as needed and take full responsibility for the content of the publication. Lu Zhang, Markus Hoffmann, *Stefan Pöhlmann spoehlmann@dpz.eu Infection Biology Unit, German Primate Center, 37077 Göttingen, Germany (LZ, MH, SP); Faculty of Biology and Psychology, Georg-August-University Göttingen, Göttingen, Germany (LZ, SP), German Center for Infection Research (DZIF), associated partner site Göttingen, Göttingen, Germany (SP) 1 Guo C, Yu Y, Liu J, et al. Antigenic and virological characteristics of SARS-CoV-2 variants BA.3.2, XFG, and NB.1.8.1. Lancet Infect Dis 2025; 25: e374–77. 2 Zhang L, Chen N, Eichmann A, et al. Epidemiological and virological update on the emerging SARS-CoV-2 variant BA.3.2. Lancet Infect Dis 2026; 26: e1–2. 3 Khare S, Gurry C, Freitas L, et al. GISAID’s role in pandemic response. China CDC Wkly 2021; 3: 1049–51. 4 Public Health Scotland. Viral respiratory diseases in Scotland surveillance report (ISO week 7). 2026. https://publichealthscotland.scot/media/37433/ week-07-19-02-26-viral-respiratory-diseases-in-scotland-surveillance- report.pdf (accessed March 23, 2026). 5 UK Health Security Agency. Influenza and COVID-19 surveillance graphs. 2026. https://assets.publishing.service.gov.uk/media/ 6995d36cbfdab2546272bf5e/weekly-flu-and-COVID-19-surveillance- graphs-week-8-2026.pdf accessed March 23, 2026). 6 White EB, O’Halloran A, Sundaresan D, et al. High influenza incidence and disease severity among children and adolescents aged <18 Years— United States, 2022–23 Season. MMWR Morb Mortal Wkly Rep 2023; 72: 1108–14. BA.3.2 and potentially future derivatives for children and young adolescents suggests that temporarily augmented protection of this age group might need to be considered. This situation is somewhat reminiscent of the 2022–23 influenza season, when particularly high disease incidence and severity was observed in individuals younger than 18 years in the USA, potentially due to insufficient vaccine coverage. 6 Furthermore, in the context of co-circulation of several SARS-CoV-2 variants, timely adaptation of vaccines might become increasingly challenging, and multivalent vaccines could be needed. Continued surveillance for SARS-CoV-2 variants, with a particular focus on variant-specific infection frequencies and disease severity in distinct age groups, will be essential to monitor this development and challenge our hypotheses regarding the reasons underlying the unexpected epidemiology of BA3.2. SP, and MH conducted contract research (testing of vaccine sera for neutralising activity against SARS-CoV-2) for Valneva, unrelated to this work. During the preparation of this work the authors used ChatGPT-5.3 (OpenAI) in order to