The number of Australian military personnel deployed overseas since 1999 now exceeds that sent to fight in Vietnam, with experts warning many may face physical or mental trauma on their return.

More than 73,000 individuals have been deployed overseas since 1999, mainly to Afghanistan, East Timor and Iraq, compared with 60,000 sent to Vietnam, figures from the Australian Defence Force show. A separate submission by the Department of Veterans’ Affairs to a recent Senate inquiry shows 81 per cent of those who served in Vietnam have had at least one disability formally accepted by the government.

DVA data also shows that there are already 3500 Afghan­istan veterans who have an ­accepted disability. The number of those suffering post-traumatic stress disorder has more than ­tripled since 2012, to more than 1000, with that figure growing by 300 a year.

The incidence of suicide among veterans also appears on the rise. The ADF submission to the Senate inquiry says 108 personnel were “suspected or confirmed to have died by suicide” since 2000, with the 47 having previously deployed. A web-based register created by Iraq veteran Aaron Gray put the number over the same period at 180.

Melbourne University health economist Philip Clarke said the community needed to prepare for a significant and ongoing cost to look after veterans, many of whom were suffering from PTSD.

Overseas analysis had shown that governments faced a very high ongoing cost — estimates of the total cost of the US involvement in Iraq and Afghanistan, ­including caring for returned military personnel, were now running at up to $US6 trillion ($8.36 trillion), Professor Clarke said. “It is important to estimate comparable costs for Australia’s involvement, and there is need for the community to understand the resources that are required to care and compensate veterans for war-related disability over the rest of their lives,” he said.

Vietnam veteran Barry Heffernan, who runs a shed for veterans in Adelaide, said many of the professionals treating returned soldiers did not have a service background and lacked understanding. “The problem is the lack of people with service backgrounds within the psych areas. You can train a psych at univer­sity but unless they have done some service, you can’t sit there and say I understand,” he said.

A veteran of Iraq and Afghan­istan who suffers from PTSD said there was a culture of denial within Defence because sufferers thought they would be discrim­inated against or pushed out if they declared their condition. He said he and many others had refused to talk about their illness.

According to DVA figures, 58,000 of those veterans deployed overseas since 1999 were sent to conflict zones. “Between 1 January, 1999, and 31 July, 2015, 73,332 individual ADF members were deployed overseas. This includes all overseas deployments, not just deployments in support of conflict zone operations,” a statement from the department said.

A Senate inquiry into the mental health of ADF personnel commences in Canberra today.

This article first appeared on ‘The Australian’ on 31 August 2015.