Over 50% of the world's population is affected by gut virus, say scientists. This virus was serendipitously found by Robert A Edwards, a bioinformatics professor at San Diego State University.

One of the most common gut bacterial species, known as Bacteroides, is infected by crAssphage virus. Researchers say that this virus can cause obesity, diabetes and other gut-related diseases.

Researchers found the virus after using results from previous studies on gut-inhabiting viruses. When the researchers examined the DNA fecal samples of 12 different people, they observed a particular group of viral DNA. In all the samples, 97,000 base pair were found common.

When researchers screened for the virus in the database of the US National Institute of Health's Human Microbiome Project (HMP), and Argonne National Laboratory's MG-RAST database, they again found the virus in abundance in human feces-derived samples.

To prove that the viral DNA is really present in environment, researchers used the method called DNA amplification, which helped them to find the virus in the original samples.

This new virus is found in the body of more than 50 % of people, but they don't know about it.

"It's not unusual to go looking for a novel virus and find one. But it's very unusual to find one that so many people have in common. The fact that it's flown under the radar for so long is very strange", Edwards said.

Edwards added that he had found this virus in some quantity in every human body.

Now, researchers are trying to produce the virus in a laboratory and their next target is to know how the virus affects the gut bacteria of human.