Border, immigration and customs staff feel unprepared to deal with people coming to the UK with possible cases of the Ebola virus, a union leader says.
Immigration Service Union (ISU) general secretary Lucy Moreton said her members needed more information on the threat.
But the Border Force has insisted staff have been given guidance on how to identify and deal with suspected cases.
Almost 700 people have died in West Africa since the first case of Ebola was detected in February.
Foreign Secretary Philip Hammond said the government was taking the current outbreak - the world's deadliest to date - and the threat to the UK "very seriously".
Ebola is a viral illness - initial symptoms can include a sudden fever, intense weakness, muscle pain and a sore throat - that can cause internal and external bleeding.
It kills up to 90% of those infected but patients have a better chance of survival if they receive early treatment.
Comment: See: Ebola - What you're not being told