When Colds Are Infectious

You're most contagious with the cold virus in the first three days of infection

Joanne Pearce
20 hours ago

No one enjoys being sick. You're tired, congested, and miserable. But the common cold is, well, common. In fact, every year Americans suffer 1 billion colds.

Adults catch two to three colds a year, whereas children tend to get them more frequently, catching as many as eight each year. It might help explain why colds cause more doctor's visits in the US than any other illness.

You're most contagious in the first three days.

It's hard to identify when exactly people stop being contagious, says Isaac Bogoch, MD, an infectious-disease consultant at the University of Toronto. But colds tend to be most contagious within the first three days the virus enters your body. That's when you'll start to feel symptoms including sneezing, a stuffy nose, scratchy throat, and mild fatigue.

Those first few days are also when you'll likely feel most miserable, so stay home in bed if you can and away from people who you might infect. After that, you still have at least five to seven days left of symptoms before you'll start to feel normal again, during which time you can still be contagious.

"There is variability as to how long people are contagious after a cold, but it can be up to five to seven days," Bogoch says.

A good rule of thumb is to assume that you're contagious for as long as you're experiencing symptoms. That may be for a week or, occasionally, in about 25% of cases, symptoms can last longer, but typically not more than 10 days.

When it's OK to return to work

Taking a week or more off work is hardly ideal, which is why Bogoch says it's OK to return to work once you've passed the peak of your symptoms and are on the mend.

You may still be contagious, which is why, according to Bogoch, if you feel well enough to return to work, you should practice impeccable hand hygiene to ensure they do not infect others.

That means keeping your hands clean by washing with soap and water or using alcohol rinse periodically. Bogoch also recommends that people seek medical attention if they experience more severe or unusual symptoms.

"If people are having shortness of breath, intractable nausea, vomiting, diarrhea, inability to keep fluids down, or if symptoms don't go away well after a week," Bogoch adds, "then you know it's time to seek medical care because it might not be a common cold."

Source:   https://www.insider.com/how-long-is-a-cold-contagious