Related Experiment Video

Updated: Aug 15, 2026

Preparation of Pseudo-Typed H5 Avian Influenza Viruses with Calcium Phosphate Transfection Method and Measurement of Antibody Neutralizing Activity
07:15

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

Published on: November 22, 2021

Human infection with an avian H9N2 influenza A virus in Hong Kong in 2003

K M Butt1, Gavin J D Smith, Honglin Chen

  • 1Department of Microbiology, The University of Hong Kong, Faculty of Medicine Building, 21 Sassoon Road, Pokfulam, Hong Kong SAR, People's Republic of China.

Journal of Clinical Microbiology
|November 8, 2005
PubMed

Insights

Avian H9N2 influenza A virus, a cause of human infections since 1998, was detected in a Hong Kong child. Genetic analysis confirmed its avian origin, closely matching viruses found in local poultry markets.

Area of Science:

  • Virology
  • Epidemiology
  • Public Health

Background:

  • Avian influenza A H9N2 viruses have been associated with sporadic human infections in Asia since 1998.
  • Poultry markets are recognized as potential interfaces for avian-to-human virus transmission.

Observation:

  • A 5-year-old child in Hong Kong was infected with an H9N2 influenza virus in 2003.
  • The human isolate, A/Hong Kong/2108/03, was genetically and antigenically characterized alongside H9N2 viruses from local poultry markets.

Findings:

  • The human H9N2 isolate was determined to be of purely avian origin.
  • The virus showed close genetic and antigenic similarity to H9N2 strains circulating in Hong Kong poultry markets.

Implications:

  • The findings highlight the ongoing risk of avian-to-human transmission of H9N2 influenza.
  • Continued surveillance of H9N2 viruses in poultry populations is crucial for pandemic preparedness.

More Related Videos

Influenza A Virus Studies in a Mouse Model of Infection10:44

Influenza A Virus Studies in a Mouse Model of Infection

Published on: September 7, 2017

Rapid Diagnosis of Avian Influenza Virus in Wild Birds: Use of a Portable rRT-PCR and Freeze-dried Reagents in the Field08:46

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

Related Concept Videos

Viral Mutations00:36

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 for adaptive...
Viral Recombination00:57

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.
Influenza01:27

Influenza

Influenza is an acute, highly communicable viral disease that affects the respiratory tract and is responsible for seasonal epidemics worldwide. Influenza A is the most prevalent type associated with widespread outbreaks and is subtyped based on two surface glycoproteins: hemagglutinin (H) and neuraminidase (N), as in H1N1. These glycoproteins are essential for viral infectivity, transmission, and immune recognition. Transmission occurs primarily through respiratory droplets and contaminated...
Coronavirus01:29

Coronavirus

Coronaviruses, including the severe acute respiratory syndrome coronavirus (SARS-CoV), are enveloped viruses characterized by their single-stranded, positive-sense RNA genome and helical nucleocapsid structure. The hallmark of these viruses is their club-shaped spike (S) glycoproteins that protrude from the viral envelope, facilitating attachment to host cells. Typically, coronaviruses infect the upper respiratory tract, often causing mild or asymptomatic disease. However, certain strains like...
Rabies01:28

Rabies

Rabies is a lethal zoonotic disease caused by a single-stranded, negative-sense RNA virus of the Lyssavirus genus, within the family Rhabdoviridae. Its primary mode of transmission to humans is through bites or saliva-contaminated scratches from infected mammals such as dogs, bats, raccoons, or foxes. Transmission can also occur if infectious saliva contacts abraded skin or intact mucous membranes, including the conjunctiva.Viral Entry and Early ReplicationOnce introduced at the bite or scratch...
Yellow Fever01:18

Yellow Fever

Yellow fever is a viral hemorrhagic disease caused by the yellow fever virus (YFV), a member of the Flaviviridae family. It is transmitted primarily by Aedes and Haemagogus mosquitoes in tropical and subtropical regions of Africa and South America. After transmission through a mosquito bite, the virus initially replicates in skin-resident immune cells such as dendritic cells and macrophages. These cells then migrate to the lymph nodes, where viral replication increases, eventually leading to...