How exactly does the flu assassinate someone?

Yes, the regular flu that kills thousands per year. Not the swine flu, which is a mutated strain of virus.
Answers:
It is not the flu itself which kills it is the opportunistic infections which may arise for example an elderly person contracts the flu (influenza) this weaken their immune system severely allowing other organisms for example pneumocystitis which can cause pneumonia to attack the body basically unchallenged.
1. immune response to the flu increasing fever, inflammation, and eventually either your lungs fill next to fluid and you can't breathe or you go into shock because all of your blood vessels dialate and you loose fluid and blood pressure
2. you gain a superimposing bacterial pneumonea which increases fever, inflammation, and your lungs fill with fluid and you can't breathe or you turn into shock because all of your blood vessels dialate and you loose fluid and blood pressure

both lead to drop off blood pressure and decreased oxygen in the blood, if you can't oxygenate your brain for 5 minutes you are brain dead, if you capture too much hypoxia in your heart you kick off a life-threatening arrhythmea where you heart doesn't beat properly and does not send blood to your brain so 5 minutes of that vehicle you are brain dead

other possibilities exist, because flu usually ends up being the straw that broke the camel's back, so alot of the patients are any old or very young or own some chronic disease that can't handle the burden of another infection
it is normally due to underlying medical conditions such as respiratory tract problems or cough

You may notice that the flu push is given to the elderly and small children or people with asthma - they are more prone to catch the flu

Also general public on immunosuppressive drugs ( weaken the immune system) due to organ transplants or other conditions are extremely prone to catching it so they have to be very reliable.

The people usually die due to the flu causing complications with their underlying complaint or other things such as fever, vomiting ( dehydration ) - possibilities are endless

Hope this helps
Paul
Some times it is the fever associated near the flu. Sometimes it is a combo of things. not getting the proper nutrition. Especially if that persons body has trouble fighting a cold, flu, etc. Weak immune system.

It really merely depends.

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