Because it is a virus
'Intractable' means difficult to manipulate, or hard to manage.
The Flu virus is so hard to combat because viruses can not be killed you just have to tough them out.
YES
it is hard to manage when my health is not good
to work hard and honest
Edwin D. Kilbourne has written: 'The Influenza viruses and influenza' -- subject(s): Influenza, Influenza viruses 'Influenza' -- subject(s): Influenza, Influenza viruses, Orthomyxoviridae
hard to manage, not easily treated, stubborn, obstinate, and hard to move forward
Fungi do not cause influenza. Viruses Cause influenza.
influenza, flue
To manage resources you have to work hard to own resources firstly. Having the right academic credentials will help you manage resources well.
There is none since "flu" is already an abbreviation for "influenza".
the batcteria moves quick and some times you dont find it until its late into the process