A GROWING number of patients travelling overseas for surgery are putting themselves and the Australian health system at risk from deadly superbugs, infectious disease experts say.

Medical tourism companies say more people are choosing to have serious surgery overseas in a shift from the cheap, cosmetic procedures the industry has traditionally performed.

Global Health Travel managing director Cassandra Italia said her company flew about 40 Australian patients a month to countries such as India, Thailand and South Korea for treatments including spinal, orthopedic and bariatric surgery.

''In the last year and half, we've seen about a 70 per cent increase in people coming to us just because they don't want to sit on waiting lists,'' she said. ''Some people are accessing their superannuation or re-mortgaging their houses to get their surgery done.''

But the trend has alarmed experts, including the Austin Hospital's director of infectious diseases, Lindsay Grayson, who said many Australians had returned from overseas surgery extremely ill because they received poor care and picked up foreign superbugs - organisms resistant to antibiotics.