Nearly half of Swedes aged between 16 and 20 think cancer is a contagious disease, according to a study by a Swedish charity supporting young patients published Wednesday.

Ung Cancer found that 44 percent of young people thought that leukaemia could be transmitted via contact with someone's blood.

"We didn't think their knowledge would be great but certain figures shocked us," said Ung Cancer's secretary general Julia Mjoernstedt.

"For example, only one percent knew that a vaccine is available against the humnan which can cause . It's terrifying."

Only a fraction of people (0.07 percent) knew that drinking alochol is a risk factor in getting cancer, although 70 percent did know about the dangers of smoking.

The charity said it would "work to increase the level of knowledge."

A total of 945 people across 13 high schools were interviewed for the study.