In the HongKong outbreak in 1997, patients had symptoms of fever, sore throat, cough and, in some fatal cases, severe respiratory distress secondary to viral pneumonia. Were affected previously healthy adults and children, and some people with chronic medical conditions.

Since then, the tests for all strains of flu virus that affects animals and humans are rapid and reliable. Many laboratories worldwide network of WHO flu have high security facilities and reagents as well as considerable experience, to carry out these tests.

It also offers Rapid bedside tests for the diagnosis of human influenza, although such tests lack the precision of the most comprehensive analysis currently required to understand the most recent cases and determine whether human infection is spreading, either directly from birds or from humans.

Antiviral drugs, some of which can be used both for the treatment and prevention, are clinically effective against virus strains in adults and children, otherwise healthy, but have some limitations. Some of these drugs are also expensive and supplies are limited.

The experience in the production of influenza vaccines is also considerable, especially considering that every year changes its composition to suit the changes in circulating virus due to antigenic drift. However, it takes at least four months to produce significant quantities of a new vaccine that protects against a new virus subtype.