Though the Ebola epidemic that has killed more than 8,000 individuals in West Africa is finally slowing down, reports that the disease has mutated have left many ion the continent worried about future outbreaks.

Researchers at the Institut Pasteur in France, who have been tracking the outbreak in Guinea, are now analysing blood samples of patients to find out whether the mutation could result in the disease becoming more contagious in future.

“We know the virus is changing quite a lot. That is important for diagnosing new cases and for treatment. We need to know how the virus is changing to keep up with our enemy,” human geneticist Dr Anavaj Sakuntabhai told the BBC.

“A virus can change itself to less deadly but more contagious and that’s something we are afraid of,” he added.

Ebola, like HIV, has a high rate of mutation, raising the chances of becoming more infectious once it has adapted to conditions. The only consolation from the study is that the possibility of the virus changing from being transmitted through body fluids to being airborne, which would make it even deadlier, is almost nil.

Given the devastation that the disease has visited upon the continent, Africa will be waiting with bated breath as scientists try to establish the level of mutation.

Last year, the World Bank said the deadly Ebola epidemic could inflict a financial blow of up to $359 million on the fragile economies of the worst affected countries in West Africa by the end of 2014.

READ: West African economies to lose $359m over Ebola

The analysis showed the loss could rise to $809 million in the worst case scenario by the end of this year if the rate of infection accelerates.

If, on the other hand, the ongoing international efforts succeed in containing the disease, the economic loss could shrink to $97 million by year end. However, the cost could be even more if the mutation creates a more virulent strain.

The three countries hope to achieve the zero cases target before the end of the year. According to the World Health Organisation, new cases in the worst hit countries have reduced compared with last year, a proof that the response to the deadly disease is finally bearing fruit.

The UN body said Sierra Leone and Guinea have recorded the lowest total of confirmed Ebola cases since August. Liberia, on the other hand, has been recording some of the lowest figures since June.

A survey done by the UN shows that case incidence has continued to fall in Guinea, Liberia, and Sierra Leone with a halving time of 1.4 weeks in Guinea, two weeks in Liberia, and 2.7 weeks in Sierra Leone.

Data on deaths, compiled by the UN, since the outbreak up to January 18 this year, shows that Liberia has lost the highest number of people (3,605), followed by Sierra Leone (3,145) and Guinea (1,876). A total of 8,641 people have died, while 21,724 have been infected.

It is not only  West African states that have suffered, East African countries, mainly Kenya and Tanzania, are continuing to incur losses in revenue as tourists shun the region for fear of contracting the disease.

According to investors in the tourism sector, many visitors stayed away from East Africa last year, since in the mind of many, the whole of the continent is a single country. Directly and indirectly, tourism accounts for almost 10 per cent of sub-Saharan Africa’s gross domestic product. The industry is worth about $170 billion a year.

According to the United Nations World Tourism Organisation, in 2013, for example, more than 55 million people visited Africa.

However, due to the Ebola threat and insecurity in parts of East Africa, some hotels and lodges were forced to lay off staff due to lack of business. The Kenya government has already conceded that the yet-to-be-released official tourism revenue figures for last year are lowerthan the ones earned the previous year.

Following the positive signs, the UN Secretary General’s Special Envoy on Ebola, David Nabarro, said the 2015 phase of the response will focus on finding and tracing all chains of transmission, treating all those who are infected and achieving zero cases throughout the region.

“It also focuses on the safe resumption of services essential for living, on strong national capacities for health security, and on ensuring that societies can respond to future outbreaks,” Mr Nabarro added.

The responses are already being adjusted in the three countries according to the different stages of the outbreak. The UN official said the organisation will use more real time and information data to facilitate an understanding of on-the-ground requirements.

“Affected communities need to be able to access public health services staffed by experts, supportive treatment, contact tracing and surveillance,” Mr Nabarro added.

Despite the positives, experts are warning that the continent is not out of the woods yet, saying that Ebola outbreaks can flare up again just as quickly as they die down.

Mr Nabarro said the UN was seeking additional funding on top of the $1 billion that has so far been donated by governments, non-governmental organisations and philanthropists.

“We need an additional focus on establishing a very strong network of virus detectives, skilled experts to search out people who have illness, to check to see if they have got Ebola, to help them isolate themselves while being treated and then to follow up their contacts. It is called case finding, surveillance and contact tracing. It’s the extra piece of work that is needed now,” he said.

According to the UN, there is no licensed vaccine to protect against Ebola yet. However, the organisation is optimistic that the goal will finally be a reality, saying some vaccine candidates are being evaluated.

The two vaccine candidates currently being tested on humans are the cAd3-ZEBOV vaccine, being developed by GlaxoSmithKline, in collaboration with the US National Institute of Allergy and Infectious Diseases, and the rVSV-ZEBOV vaccine, being developed by NewLink Genetics and Merck Vaccines USA, in collaboration with the Public Health Agency of Canada. Both vaccines have been shown to be safe and efficacious in animals.

Phase I clinical trials (to test for safety and for dose selection) are underway for both vaccines. The trials were first done in countries with no or very few cases of Ebola. The cAd3-ZEBOV vaccine trials, for example, began in the United Kingdom and the US in September and in Mali and Switzerland in October, last year. 

The rVSV-ZEBOV vaccine trials, on the other hand, began in the USA in October and in Gabon, Germany, and Switzerland in November, last year. Trials in Canada and Kenya are also due to begin this year.

The Phase II trials will test for safety and capacity to induce an immune response in larger numbers and in broader populations, including the elderly, children and persons living with HIV.

“Wide-scale introduction of the candidate vaccines in affected countries will depend on the results of the clinical trials and review by regulatory authorities of vaccine safety and efficacy,” the UN said.

Other treatments and therapies available or being evaluated include transfusion of convalescent whole blood and plasma donated by patients who have recovered.

The UN said convalescent whole blood is currently being administered in some Ebola treatment centres, while trials in Guinea and Liberia are anticipated to begin shortly.