Australian tourists in southeast Asia take too many risks and don’t have a full understanding of travel insurance, the Insurance Council of Australia (ICA) has warned.

A survey by ICA and the Department of Foreign Affairs and Trade reveals two-thirds of respondents who recently visited southeast Asia took part in a risky activity, and one in five didn’t declare a pre-existing medical condition.

One in 10 didn’t have travel insurance, and more than half of respondents didn’t know if their insurance covered the activities on their trip.

Travel insurance can be voided if a claim involves risky behaviour such as being affected by alcohol or drugs, high-risk water sports, riding a motorbike or scooter, or riding a horse, camel or elephant.

ICA says it is “increasingly concerned” for Australian travellers.

“First, we are concerned that 215,000 Australians travelled last year to southeast Asia without insurance,” a spokeswoman said. “Second, too many travellers with insurance aren’t aware of their policy inclusions and exclusions and how easily they can invalidate a claim.

“Third, many travellers fail to declare a pre-existing medical condition to their insurer.”