La gripe aviar afecta a la mayoría de las aves y produce epidemias en granjas. La enfermedad fatal se denomina “gripe aviar altamente patogénica” y se relaciona con el virus Influenza A de los subtipos H5 y H7. El reservorio natural son las aves migratorias que infectan accidentalmente a las aves domésticas. En 1997, en Hong Kong, 18 personas se infectaron por virus A(H5N1) y seis de ellas fallecieron. Al final de 2003 y principio de 2004, el mismo subtipo infectó numerosas granjas en países del sureste asiático. Este virus fue transmitido a 34 personas en contacto directo con aves infectadas y 23 personas fallecieron. La intensa investigación en curso sobre virus H5N1 se centra principalmente en su alta tasa de evolución, virulencia, probabilidad de producción de recombinantes con otros virus Influenza, variantes H5N1 capaces de infectar al ser humano o aproximaciones al desarrollo de vacunas eficaces.
Avian influenza affects most types of birds and occurs in epidemics on poultry farms. The fatal disease is named “highly pathogenic avian influenza” and is caused by influenza A virus subtypes H5 and H7. The natural reservoir is the migratory waterfowl that occasionally infects domestic poultry. In 1997 in Hong Kong, 18 persons were infected and 6 of them died. At the end of 2003 and the beginning of 2004, avian influenza H5N1 infected numerous farms in several South-Eastern Asian countries. The virus was transmitted to humans in close contact with infected birds. A total of 34 persons were infected and 23 of them died. There is currently a considerable concern about the H5N1 avian influenza that has infected humans: the high virulence, evolution rate, the possibility of recombination with other influenza viruses, how H5N1 variants that infect humans or different approaches to the development of influenza vaccines.
