Evidence map›Paper›PMID 42532224›Full record

ReviewThe Journal of infection2026

Pre-existing and cross-reactive immunity to avian influenza H5N1 in humans: Implications for pandemic risk and vaccine strategies.

Iván Sanz-Muñoz, Carlos J Ciria-Gil, Marta Hernandez, Cesar Santiago, Ahmed M Elsayed, Jose M Eiros, Luis Martinez-Sobrido, Aitor Nogales

Abstract readReview
In one paragraph

Review in The Journal of infection, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

8 authors.

Iván Sanz-MuñozNational Influenza Centre, Hospital Clinico Universitario de Valladolid, Valladolid, Spain; Instituto de Estudios de Ciencias de la Salud de Castilla y León, ICSCYL, Soria, Spain; CIBERINFEC, Centro de Investigacion Biomedica en Red de Enfermedades Infecciosas, Instituto de Salud Carlos III, Madrid, Spain.
Carlos J Ciria-GilCenter for Animal Health Research, CISA-INIA-CSIC, Madrid, Spain.
Marta HernandezNational Influenza Centre, Hospital Clinico Universitario de Valladolid, Valladolid, Spain; Department of Microbiology, Universidad de Valladolid, Valladolid, Spain.
Cesar SantiagoX-ray Crystallography Facility, Department of Macromolecules Structure at CNB, CSIC, C/Darwin 3, Campus Universidad Autónoma de Madrid, 28049 Madrid, Spain.
Ahmed M ElsayedTexas Biomedical Research Institute, San Antonio, TX, USA; Center of Scientific Excellence for Influenza Viruses, National Research Centre, Giza, Egypt.
Jose M EirosNational Influenza Centre, Hospital Clinico Universitario de Valladolid, Valladolid, Spain; Department of Microbiology, Universidad de Valladolid, Valladolid, Spain; Microbiology Unit, Hospital Clínico Universitario de Valladolid, Valladolid, Spain; Microbiology Unit, Hospital Universitario Rio Hortega, Valladolid, Spain.
Luis Martinez-SobridoTexas Biomedical Research Institute, San Antonio, TX, USA.
Aitor NogalesCenter for Animal Health Research, CISA-INIA-CSIC, Madrid, Spain; Center for Influenza Disease and Emergence Response (CIDER), Madrid, Spain. Electronic address: nogales.aitor@inia.csic.es.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Due to the continuous evolution of Influenza A viruses (IAVs), novel strains with efficient human-to-human transmission may emerge and cause future pandemics. Among these, highly pathogenic avian influenza (HPAI) H5N1 remains a major concern because of its impact on wildlife, livestock, and human health. The widespread circulation of H5N1 clade 2.3.4.4b, detected in hundreds of bird species and numerous mammals worldwide, highlights important changes in viral ecology and transmission, increasing its zoonotic and pandemic potential. This review summarizes current evidence on cross-reactive and cross-protective immunity to H5N1 in humans, focusing primarily on humoral immune responses. We examine the presence of pre-existing H5N1-reactive antibodies in individuals without known exposure and discuss how previous seasonal influenza infection or vaccination may contribute to their development. Particular attention is given to antibodies targeting conserved regions of hemagglutinin (HA), especially the stalk domain, as well as neuraminidase (NA), which may provide heterosubtypic protection. We also evaluate the ability of seasonal influenza vaccines and infections to induce cross-reactive responses against H5N1 and their potential role in partial protection or immune priming. Finally, we review current and emerging H5N1 vaccination strategies, including adjuvanted and mRNA-based platforms, and identify priorities for surveillance, population immunity assessment, and the development of broadly protective influenza vaccines.

Indexed as

Antibodies, ViralCross ProtectionInfluenza A Virus, H5N1 SubtypeInfluenza, HumanInfluenza VaccinesPandemicsAnimalsBirdsCross ReactionsHemagglutinin Glycoproteins, Influenza VirusHumansImmunity, HumoralInfluenza in BirdsAntibodies, ViralHemagglutinin Glycoproteins, Influenza VirusInfluenza VaccinesAntibodiesCross-reactivityH5N1 SubtypeHumoralImmunityInfluenza A VirusInfluenza vaccinesZoonoses

Identifiers

PMID42532224
PMCPMC13619460

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.