THE Ebola crisis in West Africa has developed at an unprecedented level, experts have warned.

The current rate of ­infection stands at 1.7, meaning that for every 10 people who contract the virus, a further 17 will also be infected.

The aim is to reduce the rate to one, and eventually below one, in the fight to stop the spread of the deadly disease.

Experts believe they have a 90-day window to halt the spread of Ebola, which could otherwise infect 1.5 million people by January. The death toll from the infection, which has spread across Guinea, Liberia and Sierra Leone, has reportedly risen to more than 3,000.

More than 40 British ­military personnel and aid experts are now working in Sierra Leone following a direct request for assistance from the World Health Organisation and the country's government.

A spokesman for the Department for International Development (DfID) said: "This is on an unprecedented level and to a scale that we have not seen with previous Ebola outbreaks.

"Without further ­immediate action it could have serious far-reaching consequences beyond the effects to health, including the availability of basic services, security implications and economic stability."

More than 160 NHS staff are also due to travel to Sierra Leone after answering a call for volunteers to help fight the disease earlier this month.

Britain is also to provide 700 extra beds to treat people affected by the highly contagious virus as part of a £100 million aid package.