Only four of the 111 refugees and asylum seekers transferred to Australia under controversial medical transfer laws have been admitted to hospital for treatment.

"When these patients arrive, we see very low instances of hospitalisations - and in fact there are very few outpatients," Australian Department of Immigration and Border Protection secretary Mike Pezzullo told a Senate committee hearing on Monday.

Mike Pezzullo says none of the refugees transferred under medevac laws are in hospital. Credit:Alex Ellinghausen

The Coalition, which wants to repeal the so-called "medevac" laws, is expected to seize on the numbers to back its argument that the legislation is being used by activist doctors to bring refugees to Australia permanently.

Mr Pezzullo told the Senate committee hearing that one of the 111 transferred asylum seekers was refusing treatment. None of those transferred remained in hospital as of Thursday and almost two-thirds were "not even outpatients", he said.