Britain is stepping up checks for Ebola at UK borders amid an outbreak in central Africa.

Posters outlining Ebola symptoms and informing passengers on what to do if they become sick have gone up at Heathrow, Gatwick and Manchester airports, as well as St Pancras and Birmingham railway stations.

Produced by the UK Health Security Agency (UKHSA), they are aimed at people returning from Uganda and the Democratic Republic of Congo (DRC), the two countries that have so far reported cases of the rare Bundibounya species of Ebola.

Passengers have been urged to alert NHS 111 “immediately” if they develop symptoms of the disease, including a high temperature, extreme tiredness, blood in their poo, bruises over the body, or yellowing of the skin and eyes and alert authorities to their travel history.

Ebola can develop between two and 21 days after infection, the posters add.

If a person in the UK were to test positive for the virus, they would then be transferred to one of the UK’s High Level Isolation Units – specialist wards designed for the containment and treatment of dangerous infectious diseases.

Only a handful of hospitals operate such wards, including the Royal Free in North London, where Pauline Cafferkey, the Scottish nurse who contracted Ebola in 2014, was treated, and the Royal Victoria Infirmary in Newcastle.

According to the Foreign Office, announcements will also now be made on direct flights from the affected region, asking them to declare themselves to cabin crew if they feel unwell so that they can be assessed by specialist health teams when they land.

Four direct flights operate from Uganda to Britain every week, landing at Gatwick.

While there are no direct routes from the DRC to the UK, travellers from the Congo typically reach British airports through connecting flights, provided by several major carriers like Air France and Brussels Airlines.

Government officials said they had ruled out temperature checks at airports, a measure which was used in the 2014-2016 West Africa Ebola outbreak, because they are not always effective.

Nurse Cafferkey, who caught Ebola in Sierra Leone before travelling back to the UK, passed multiple airport temperature checks before being hospitalised with the virus days after her return.

The current outbreak, which is centred on the Ituri region in the eastern DRC, has so far infected 321 people with a further 116 suspected cases. At least 48 people have died.

The Bundibugyo species of Ebola has no vaccines or treatments, and containing the virus is proving notoriously difficult.

Mistrust of healthcare workers as well as a protracted conflict in the region is further complicating relief efforts, according to aid agencies on the ground.

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