Illustrative examples of correct usage

In technical contexts, correct usage of terms is necessary because precise distinctions are the essence of the communication.

* "Avian influenza strains are those well adapted to birds"[1]
* "An outbreak of influenza A (H5N1), also known as 'avian flu' or 'bird flu,' has been reported in several countries throughout Asia."[10]
* "Avian influenza virus usually refers to influenza A viruses found chiefly in birds, but infections can occur in humans."[11]
* "Of the few avian influenza viruses that have crossed the species barrier to infect humans, H5N1 has caused the largest number of cases of severe disease and death in humans. Unlike normal seasonal influenza, where infection causes only mild respiratory symptoms in most people, the disease caused by H5N1 follows an unusually aggressive clinical course, with rapid deterioration and high fatality." Seasonal influenza is human flu.[12]
* "avian influenza HA bind alpha 2-3 sialic acid receptors while human influenza HA bind alpha 2-6 sialic acid receptors. Swine influenza viruses have the ability to bind both types of sialic acid receptors."[13]
* Sometimes a virus contains both avian adapted genes and human adapted genes. Both the H2N2 and H3N2 pandemic strains contained avian flu virus RNA segments. "While the pandemic human influenza viruses of 1957 (H2N2) and 1968 (H3N2) clearly arose through reassortment between human and avian viruses, the influenza virus causing the 'Spanish flu' in 1918 appears to be entirely derived from an avian source (Belshe 2005)."[2]

[edit] Illustrative examples of imprecise usage

In nontechnical contexts, imprecise usage of terms is typical when discussing complex things.

* "A 1,000 square mile quarantine zone to combat an outbreak of bird flu was lifted in Scotland today - despite the spread of a similar disease south of the border." Here "bird flu" is used to mean "Asian lineage HPAI A(H5N1) flu" (which is a bird flu) and contrasted with flu from an avian adapted strain of H7N3 (which is also a bird flu).[14]