<s>[INST] I have a cold or the flu, how long will I be contagious? [/INST] If you catch the flu, you’re contagious for one to two days before you start to show symptoms and for five to seven days after becoming sick. That means you may be able to pass on the flu to someone before you know you are sick as well as while you are sick. As for a cold, you are most contagious for the first 2 or 3 days. A cold is usually not contagious after the first week. Source: Theraflu. Link: https://www.theraflu.com/faqs/  . Field: General Medicine. Disease: Cold </s>