No. You may develop immunity to one or more types of influenza virus by having been infected or immunized, but this virus undergoes regular changes in its make-up and the new strain present in the community can infect you even if you are immune to other strains. On the other hand, if you are asking about recovery from infection, when you recover you will rid of that strain of flu virus.
Yes. This is one of the reasons influenza vaccine has to be reformulated each year.
About a week. A person sheds the virus for about seven days.
May be difficult. Rapid influenza testing by nasal swab, viral cultures, or retrospectively by serologic testing. There are many viral infections which can mimic influenza, inclluding parainfluenza, some adenoviruses, and so on and so on. Generally influenza will be active in the community and doctors, having been informed of this by the health departments, will have high indices of suspicion.
Immunity & exposure. Once infected the flu runs its course until treated early on by an antiviral medication. It is just the nature of the beast. Hope you feel better soon.
Sick. Drink lots of fluid, rest and otc meds all help. If its the flu you can ask your doctor about Tamiflu (oseltamivir). Hang in there.
Not long. As you recover from influenza the body is building antibodies which attack and kill the virus.
About 24 hours in. The environment. Flu virus is present and shed from an infected person for about a week. On inanimate objects it usually does not last longer than 24 hours, mostly about 4 hours.
Rest, fluids, soup. The "flu" is a bad bug. We recommend getting vaccinated to prevent this illness. To treat for "free" try increasing fluids, resting (important to prevent spread) and chicken noodle soup. Why? Because if mom, wife, partner makes it for you there is someone trying to make you better and this helps recovery. By the way-where are you seeing flu now? Our surveillance isn't showing this anywhere now.
Good question. Because a virus is DNA or RNA, I used to think that a virus could not survive at all outside a cell. In reviewing the literature a while ago, I found to my surprise that some viruses can remain for days or weeks on inanimate objects and in water or sewage for very long periods of time. So it depends on the virus but they can survive outside the body for days to months.