Detainees on Manus Island have to wait five to seven days to see a doctor unless it is deemed an "absolute emergency", a Manus Island whistleblower has told Crikey.

Martin Appleby, a former guard at the Manus Island detention centre, says it would also be impossible for doctors to test for the septicaemia that has left Hamid Kehazaei brain-dead in Brisbane's Mater Hospital. "There's no way you can take blood and get it tested. There was no ice to pack the blood in to get it Port Moresby for testing."