Experts say pre-migration screening of immigrant children for TB needs be improved.

Children born overseas make up more than half of Australia's tuberculosis cases in youngsters, prompting experts to call for improved pre-migration screening.

Children under 15 accounted for just under five per cent of all TB patients in Australia from 2003-2012, says new research published in the Medical Journal of Australia.

But 56.1 per cent of the 538 children were born overseas, while their annual notification rate was 9.57 per 100,000 child population.

The notification rate for Australian-born children was 0.61 per 100,000, but the rate was three times higher for indigenous children than for non-indigenous children.

The data was collected from the National Notifiable Diseases Surveillance System.

"Despite the strong link with recent immigration that we found, only a minority of children with TB (8.7 per cent) were detected by specific onshore post-arrival immigration screening," wrote the researchers, led by Dr Stephen Teo from Western Sydney University.

"Passive case detection identified most cases, including the overseas-born children who were typically diagnosed within two years of their arrival."

This may indicate that the offshore screening process is inadequate, or that most overseas-born children with TB did not have active disease at the time of their initial screening.

"This suggests that there is potentially a role for preventive therapy in immigrant children with latent TB infection from high-incidence countries, which could be supported by introducing improved pre-migration screening of younger children."