It might sound contradictory, but the common cold or a bad case of the flu isn’t the only thing that’s going around. Loneliness can actually be spread from one person to another, researchers have found. Yes, that’s right… loneliness is believed to be contagious.

How can this be true? A federally funded study analyzed data from more than four-thousand people over a period of ten years. The researchers found that people who know lonely people are themselves more likely to feel isolated. These feelings can even spread by a degree of separation, causing a friend of a friend or a sibling to feel blue.

It seems unlikely… how can an emotion be contagious? But researchers say it makes sense. If a person is lonely, he or she is more likely to act in negative ways around other people. This perpetuates the behavior.

Other studies have shown that many behaviors are easily spread among social groups, in some cases leading to obesity, or influencing the likelihood of quitting smoking and happiness. For this particular study, researchers interviewed more than forty-seven hundred people every two years between 1991 and 2001. They found that the friend of a lonely person was fifty-two percent more likely to develop feelings of loneliness by the time of the next interview. The connection was most powerful between friends and neighbors and was weaker between siblings and spouses.

So if you’ve been feeling lonely, take a look at the company you keep. Maybe the key to breaking out of a funk is to surround yourself with happy, lively people.