The size of time you're transmittable for after having a famous infection relies on the form of virus involved.

You are watching: How long is the flu virus contagious

The infectious period often begins before you begin to feeling unwell or an alert a rash.

Bronchitis

The size of time that bronchitis is transmittable varies, depending on its cause.

In many cases, bronchitis is caused by the exact same viruses that reason the common cold or flu, and also you're most likely to be contagious as lengthy as you have actually cold or flu symptoms.

Chickenpox

Chickenpox is transmittable from 2 days prior to the spots appear to until they have actually crusted over, typically 5 work after they an initial appeared.

Common cold

The common cold is contagious from a couple of days prior to your symptoms appear until all of the symptoms are gone. Most human being will be contagious for roughly 2 weeks.

Symptoms are usually worse throughout the first 2 come 3 days, and this is when you're most most likely to spread out the virus.

Flu

Flu is normally most contagious from the day her symptoms start and also for a additional 3 come 7 days.

Children and people with lowered immune systems may be contagious for a couple of days longer.

Glandular fever

Glandular fever isn't specifically contagious and also can usually just be spread out through direct contact with saliva, which is why it's sometimes referred to as "the kissing disease".

There's no reason not to continue to go to college or work-related if you feeling well enough.

Measles

Symptoms of measles show up around 10 job after you become infected.

Measles is most infectious after the an initial symptoms appear and also before the rash develops.

First symptoms the measles include:

a high temperaturered eyescold-like symptom – such together a runny nose, watery eyes, puffy eyelids and sneezing

Around 2 come 4 job later, a red-brown spotty rash establishes that normally fades after about a week.

Mumps

Mumps causes your salivary glands come swell. This glands are just below and also in prior of her ears.

Mumps is most transmittable from a few days before your glands swell till a few days afterwards.

Rubella (german measles)

People through rubella should stay off school or work, and also avoid contact with pregnant women whereby possible, because that 6 days after the rash firsts develops.

Shingles

You can't spread shingles come others. However people that haven't had actually chickenpox before could catch chickenpox native you.

Shingles is transmittable while the rashes oozes fluid.

See more: How Many Times Does A Tattoo Peel Ing: Is It Normal For Ink To Flake Away?

Tonsillitis

Tonsillitis chin isn't contagious, however the viruses that cause it are. The length of time you're contagious will count on the virus.