Scientists claim people can catch a bug which makes them obese, the Sun has reported.

The virus can be spread like a cold, and picked up from a sneeze, a cough or dirty hands.

Professor Nikhil Dhurandhar said the virus, known as AD-36, goes to the lungs then whisks around the body, forcing fat cells to multiply and also causes sore throats.

“When this virus goes to fat tissue it replicates … which may explain why people get fat when infected,” said Dhurandhar .

In one test, a third of obese people had the rare and highly contagious virus compared to just 11 percent of thinner people. Weight gain can last three months until the body has built up resistance to the bug.

New research supports earlier theories from studies on weight gain; evidence in tests on mice and chickens shows the bug could cause overweight people to gain weight.

“People could be fat for reasons other than viral infections, so it’s pointless for fat people to try to avoid infection,” said Dhurandhar.

The study also reveals research claiming dieters always feel hungry because humans have a “natural body weight” and they will always suffer hunger pangs.