Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Viral Mutations

Viral Mutations

A mutation is a change in the sequence of bases of DNA or RNA in a genome. Some mutations occur during replication of the genome due to errors made by the polymerase enzymes that replicate DNA or RNA. Unlike DNA polymerase, RNA polymerase is prone to errors because it is not capable of “proofreading” its work. Viruses with RNA-based genomes, like HIV, therefore accrue mutations faster than viruses with DNA-based genomes. Because mutation and recombination provide the raw material...

Viral Recombination

Viral Recombination

Cells are sometimes infected by more than one virus at once. When two viruses disassemble to expose their genomes for replication in the same cell, similar regions of their genomes can pair together and exchange sequences in a process called recombination. Alternatively, viruses with segmented genomes can swap segments in a process called reassortment.

Horizontal Gene Transfer

Horizontal Gene Transfer

Horizontal gene transfer (HGT) is a process where genetic material moves between organisms within the same generation, unlike vertical gene transfer, which occurs from parent to offspring. HGT plays a crucial role in microbial evolution, adaptation, and survival, particularly in shared environments like the human gut.Mobile genetic elements such as plasmids, prophages, integrons, insertion sequences, and transposons facilitate this process. HGT occurs through three primary mechanisms:...

The Evidence for Evolution

The Evidence for Evolution

Genetic variations accumulating within populations over generations give rise to biological evolution. Evolutionary changes can result in the formation of novel varieties and entire new species. These changes are responsible for the diverse forms of life inhabiting the planet. The evidence for evolution suggests that all living organisms descended from common ancestors.

Gene Flow

Gene Flow

Gene flow is the transfer of genes among populations, resulting from either the dispersal of gametes or from the migration of individuals.

Infection

Infection

When a pathogen enters the body and reproduces, it can cause an infection, damage body cells, and cause illness symptoms that eventually lead to disease. Therefore, its prevention requires breaking the chain of infection.
The chain begins with pathogens: bacteria, viruses, fungi, prions, or parasites such as protozoa helminths. These can be present on the skin as transient or resident flora, or they can be acquired from the environment. Identifying and treating the type of infection and...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Development and characterization of mouse-adapted recombinant SARS-CoV-2 expressing reporter genes.

Microbiology spectrum·2026

Same author

Identification and characterization of a SARS-CoV-2 M<sup>pro</sup> G23 deletion ensitrelvir-resistant mutant.

mBio·2026

Same author

Developmental candidate GHP-88310/EIDD-3608 with high tolerability and oral efficacy in measles and respiratory paramyxovirus models.

Science advances·2026

Same author

Identification and characterization of novel chikungunya virus polymerase inhibitors.

Journal of virology·2026

Same author

Differential inhibition of Morbillivirus and Henipavirus polymerases by ERDRP-0519 and structure-guided inhibitor optimization.

Cell·2026

Same author

Efficacy of the nucleoside analog 4'-Fluorouridine against Nipah virus in the Syrian hamster model.

PLoS pathogens·2026

Search research articles

Related Experiment Video

Updated: Jan 16, 2026

Rapid Diagnosis of Avian Influenza Virus in Wild Birds: Use of a Portable rRT-PCR and Freeze-dried Reagents in the Field

Rapid Diagnosis of Avian Influenza Virus in Wild Birds: Use of a Portable rRT-PCR and Freeze-dried Reagents in the Field

Published on: August 2, 2011

H5N1 Clade 2.3.4.4b: Evolution, Global Spread, and Host Range Expansion.

Klaudia Chrzastek¹, Carolin M Lieber², Richard K Plemper²

¹Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA.

Pathogens (Basel, Switzerland)

|September 27, 2025

Summary

Highly pathogenic avian influenza viruses (H5 HPAIVs) are a global threat. The H5 clade 2.3.4.4b is expanding, causing mammalian infections and highlighting the need for surveillance.

Keywords:

AIV H5N1 HPAIV clade 2.3.4.4b epidemiology mammalian infection

More Related Videos

Preparation of Pseudo-Typed H5 Avian Influenza Viruses with Calcium Phosphate Transfection Method and Measurement of Antibody Neutralizing Activity

Preparation of Pseudo-Typed H5 Avian Influenza Viruses with Calcium Phosphate Transfection Method and Measurement of Antibody Neutralizing Activity

Published on: November 22, 2021

Avian Influenza Surveillance with FTA Cards: Field Methods, Biosafety, and Transportation Issues Solved

Avian Influenza Surveillance with FTA Cards: Field Methods, Biosafety, and Transportation Issues Solved

Published on: August 2, 2011

Related Experiment Videos

Last Updated: Jan 16, 2026

Rapid Diagnosis of Avian Influenza Virus in Wild Birds: Use of a Portable rRT-PCR and Freeze-dried Reagents in the Field

Rapid Diagnosis of Avian Influenza Virus in Wild Birds: Use of a Portable rRT-PCR and Freeze-dried Reagents in the Field

Published on: August 2, 2011

Preparation of Pseudo-Typed H5 Avian Influenza Viruses with Calcium Phosphate Transfection Method and Measurement of Antibody Neutralizing Activity

Preparation of Pseudo-Typed H5 Avian Influenza Viruses with Calcium Phosphate Transfection Method and Measurement of Antibody Neutralizing Activity

Published on: November 22, 2021

Avian Influenza Surveillance with FTA Cards: Field Methods, Biosafety, and Transportation Issues Solved

Avian Influenza Surveillance with FTA Cards: Field Methods, Biosafety, and Transportation Issues Solved

Published on: August 2, 2011

Area of Science:

Veterinary Virology
Zoonotic Disease Epidemiology
Molecular Evolution

Background:

Highly pathogenic avian influenza viruses (HPAIVs) of the H5 subtype are a significant global threat to animal and public health.
The A/goose/Guangdong/1/96 (GsGD) H5 lineage, emerging in 1996, has diversified into multiple clades, causing widespread outbreaks in poultry and wild birds.
Global spread has been primarily observed in three clades: 2.2, 2.3.2.1, and the more recent 2.3.4.4b.

Purpose of the Study:

To review the historical emergence and global spread of H5 HPAIVs.
To analyze the molecular evolution of H5 HPAIVs.
To focus on the recent expansion and mammalian spillover capacity of H5 clade 2.3.4.4b.

Main Methods:

Literature review of scientific publications and outbreak reports.
Analysis of epidemiological data on H5 HPAIV spread.
Examination of molecular data related to H5 HPAIV evolution.

Main Results:

H5 HPAIVs, particularly clade 2.3.4.4b, demonstrate continuous geographic expansion and adaptation to new environments, including Antarctica.
Clade 2.3.4.4b has shown increasing reports of infections in various mammalian species, including companion animals, marine mammals, and livestock.
Recent evidence of cow-to-cow and cow-to-human transmission signifies a critical shift in avian influenza epidemiology.

Conclusions:

The H5 HPAIV clade 2.3.4.4b represents a growing concern due to its global reach and demonstrated capacity for mammalian spillover.
The recent transmission events in cattle underscore the evolving zoonotic potential of H5 HPAIVs.
Continued global surveillance and research are essential to monitor the evolution and spread of H5 HPAIVs and mitigate their impact on animal and public health.