Australia needs to “look closely” at whether the threshold age for receiving the AstraZeneca COVID-19 vaccine should be raised to 60 in the wake of severe cases of thrombosis with thrombocytopenia syndrome, a leading expert on the rare disorder says.

The Australian Technical Advisory Group on Immunisation’s (ATAGI) advice is that the Pfizer vaccine is preferred for people under 50 because of a higher incidence of thrombosis with thrombocytopenia syndrome (TTS).

But in the wake of a second death linked to the viral-vector vaccine, haematologist Professor Huyen Tran told the ABC’s 7.30 program that the severity of the syndrome in younger people, not just the incidence, should be taken into account.

“It appears from the data coming out of Europe and in the UK, the more severe cases certainly involve younger people under the age of 60,” he said on Monday.