The Institut Pasteur in France is now trying to find out whether these mutations have increased the virus' ability to spread and infect more people (Representational Image)Reuters

French scientists investigating the current Ebola outbreak warn that the virus has mutated and changed since the beginning of the outbreak in early 2014.

The Institut Pasteur in France is now trying to find out whether these mutations have increased the virus' ability to spread and infect more people, the BBC reported.

For this purpose, they have already collected nearly 600 blood samples from people who tested positive for Ebola in Guinea.

"We know the virus is changing quite a lot," human geneticist at the Institut Pasteur, Dr Anavaj Sakuntabhai, told BBC. "That's important for diagnosing (new cases) and for treatment. We need to know how the virus (is changing) to keep up with our enemy."

The deadly disease spreads when a person comes into direct contact with blood or bodily fluids of an infected person. Symptoms include body ache, high fever, vomiting, diarrhoea, haemorrhaging and joint pain.

The current outbreak looked different from previous ones, basically in terms of symptoms. Researchers said many Ebola patients in the current outbreak did not develop any symptoms. This is really concerning as it can help spreading of the virus. 

"We've now seen several cases that don't have any symptoms at all, asymptomatic cases," Sakuntabhai added. "These people may be the people who can spread the virus better, but we still don't know that yet. A virus can change itself to less deadly, but more contagious and that's something we are afraid of."

Meanwhile, another concern is that, these mutations can eventually make the virus airborne. The chances, according to the experts, are very less as no blood-borne virus has shown this tendency until now.

However, an online investigation shows that Ebola virus hasn't changed much since it first appeared on the earth, ie in 1976. A CDC data shows only a mere 3% change in the virus now compared to the 1976 virus.

However, the experts did not completely rule out the possibility of the virus becoming airborne in the future.

"Over the course of millions of years, viruses do sometimes mutate to change how they spread infection. For Ebola, this would require multiple mutations in the virus over a very long period of time," read a report released by the CDC.

A recent study conducted by the US Army Medical Research Institute of Infectious Diseases (USAMRIID) in Frederick, Maryland, earlier this month showed that the Ebola strain was mutating rapidly.

Jeffrey Kugelman, a viral geneticist at USAMRIID, and colleagues have identified nearly 600 genetic mutations called single nucleotide polymorphisms (SNPs) in EBOV/Mak, the strain involved in the current Ebola outbreak.

Considered to be the biggest outbreak of Ebola in the human history, the deadly virus has, until now, infected 22,057 people and killed 8,795 of them across the world.