The first person to be diagnosed with the Ebola virus in the US is now in a critical condition, according to the hospital where he is being treated.
Thomas Eric Duncan, who arrived in the US having travelled from his native Liberia via three countries, has been held in isolation at Texas Health Presbyterian Hospital in Dallas having being diagnosed with the virus which has killed more than 3,000 people in West Africa.
Doctors at the hospital have now confirmed via a short statement that Duncan is in critical condition having previously being described as serious but stable.
Health officials at the US Centers for Disease Control and Prevention (CDC) have identified 10 people who have come into contact with Duncan who may have contracted the disease through him. A further 40 people are also been monitored for symptoms of Ebola.
So far none are showing symptoms of the virus.
Duncan's diagnosis has caused fears the deadly disease could spread in the US. Health officials said they are confident they will be able to control the virus, which cannot spread through the air and can only be contracted with direct contact with bodily fluids of an infected person
A father and daughter were recently removed from a United Airlines flight from Brussels after showing symptoms of the Ebola virus. The Liberian man was escorted off the flight after the plane landed in New Jersey after vomiting on board.
All the other passengers were eventually cleared to leave the plane, but airport officials the CDC they do not believe the man was infected.
The World Health Organisation (WHO) assured people that the deadly disease is not airborne following recent speculation. A spokesperson said: "Following recent media reports, the UN Mission for Ebola Emergency Response (UNMEER) seeks to clarify that Ebola is not an airborne disease.
"At this point in time we have no evidence and do not anticipate that the Ebola virus is mutating to become airborne.
"However, there are real risks and concerns with this outbreak: every day more people are becoming infected and more are dying because they cannot get the care they need. Energy needs to be focused on swiftly addressing the real needs and gaps in communities affected by this disease."
The WHO has now recorded a death toll of 3,439 out of 7,492 suspected, probable and confirmed cases in the worst Ebola outbreak in history.