Prime Minister David Cameron will for the first time chair a meeting of the government's emergency response committee on Wednesday to discuss the threat of Ebola, seeking to assuage growing public concern about the spread of the deadly virus to Europe, according to Reuters. The meeting comes amid fears that the worst Ebola outbreak on record could spread beyond West Africa after a nurse in Spain became the first person known to have caught the virus outside Africa and the World Health Organisation warned that Europe was almost certain to see further cases. Senior ministers and officials will examine the country's preparedness for an Ebola outbreak, with one government minister calling for a review of border precautions. Ebola has killed more than 3,400 people in Guinea, Sierra Leone and Liberia, and its spread has become a global concern - even hurting the value of Britain's top share index over fears it could affect the airline and tourism trade. The chairman of government body Public Health England, David Heymann, said that authorities had worked for many years to make sure it was prepared to handle the virus if it arrived in Britain and that there was no crisis in the country. However junior Home Office minister, Norman Baker, told the Independent that precautions may need to be stepped up. "We need to consider whether existing controls are adequate," he said. Public Health England said in a statement on Tuesday that there was a low, but real, risk of importing the disease from West Africa, but that there were no plans to introduce screening at airports. "It's very difficult to monitor and to stop infections at borders because many people who are infected cross borders in the asymptomatic phase when they have no signs and symptoms," Heymann told BBC radio on Wednesday. U.S. authorities are preparing tougher Ebola screening at American airports. Any cases discovered in Britain would be directed to London's Royal Free Hospital which has a specialist unit capable of treating two patients and could expand its capacity if necessary, a health service spokeswoman said. A British aid worker who contracted the virus in Sierra Leone was successfully treated at the Royal Free and discharged in September. Cameron's office said that although it was the first time he had personally chaired a meeting on Ebola it was not a specific reaction to events in Spain and elsewhere, and had long been scheduled to take place. The committee has been discussing Ebola since July, a spokesman said.