If the world doesn't get the Ebola outbreak in West Africa under control quickly, the disease could become a permanent fixture in the region, spreading as routinely as malaria or the flu, the World Health Organization warns Tuesday in a new report.

In the worst-case scenario – if nothing is done to effectively control the outbreak — there could be 1.4 million Ebola cases in Liberia and Sierra Leone by the end of January, according to a report released Tuesday by the Centers for Disease Control and Prevention.

CDC officials say it's still possible to avoid this worst-case. USA Today reports.

"It is still possible to reverse the epidemic, and we believe this can be done if a sufficient number of all patients are effectively isolated, either in Ebola Treatment Units or in other settings, such as community-based or home care," said Tom Frieden, director of the Centers for Disease Control and Prevention.

"Once a sufficient number of Ebola patients are isolated, cases will decline very rapidly – almost as rapidly as they rose. … A surge now can break the back of the epidemic."

The notion that Ebola could become endemic in West Africa —— spreading routinely, rather than in sporadic outbreaks — is "a prospect that has never before been contemplated," according to a report published online in the New England Journal of Medicine.

There could be 20,000 cases by Nov. 2, with thousands of new cases per week, the report said. About 70% of patients are dying from the illness.