If strep bacteria causes the infection, it can remain contagious for up to 2 weeks without treatment. However, antibiotics can shorten the contagious period and limits to about 24 to 48 hours once the therapy starts. http://health.top54u.com/post/How-Long-is-Tonsillitis-Contagious.aspx
An upper respiratory infection is contagious for as long as the active virus is in your system. Taking an antibiotic will help rid the body of the live virus. You will remain contagious for 24 hours following the first treatment of the antibiotic.
Septic tonsillitis, also known as streptococcal tonsillitis, is contagious until the person has been on antibiotics for at least 24-48 hours. It is important to finish the full course of prescribed antibiotics to prevent spreading the infection to others. Close contacts may also need to be evaluated and treated if necessary.
3 days
Approximately 48 hours.
The mono virus is contagious before the person even knows they have the illness; this is called the incubation period. It is contagious the whole time the person has mono.
The germs that caused the virus are still in you and reproducing for most of the time you are on antibiotics. The anitbiotics kill them. As they die, they're numbers dwindle, but are still there, so you are still contagious until all the antibiotic is gone and the doctor confirms the virus is gone. It is important to use all the prescribed antibiotic--to be sure to kill off all the germs. If not, some may be left and start reproducing again, thus you'd have to start all over with the antibiotics.
Every virus is different. Some are infectious for only a couple of days; some are infectious until after your body has been buried. Some may be infectious for longer than that; bodies of the victims of the 1917 influenza strain have recently been exhumed, and were discovered to STILL be dangerous.
How long is the 24 stomach flu contagious for
Very contagious if you haven't been immunized.
Up to 24 hours after it has been treated with antibiotics. You should stay home from work or school at least 24 hour after receiving an antibiotic shot or starting an oral antibiotic treatment even if you feel better. You should also finish all your antibiotic pills, for the full ten days, even after you feel better to prevent further infection or relapse.
About a week or something like that
The child is considered as contagious for ten days on azithromycin. ( Now that, contributor got the point, as to why strep throat is uncommon in developed countries.)