The Ebola outbreak in West Africa continues to rage out of control. The deadly hemorrhagic fever has infected over 5,700 in the region and has killed nearly 2,800. With thousands of American defense officials poised to head to the hot zone in the coming days, the American Center for Disease Control is set to warn that disease is spreading exponentially and may infect up to 500,000 by the end of January.

A report due to be released this week projects that a half a million could be infected by mid-winter, but the model presumes no additional assistance from the international community to curtail the epidemic’s rapid expansion.

“CDC is working on a dynamic modeling tool that allows for recalculations of projected Ebola cases over time,” a CDC spokeswoman told reporters with The Washington Post. “CDC expects to release this interactive tool and a description of its use soon.”

The World Health Organization said last month that the outbreak could reach 20,000 cases before it is brought under control. But infectious disease experts, aid officials and global health advocates said cases are increasing so rapidly that the total number is almost certain to be much higher, especially in the worst-affected countries of Liberia, Guinea and Sierra Leone.

The CDC further issued a series of new guidelines to American air carriers on Monday aimed at preventing the spread of the virus via air travel. The CDC recommended that US airlines prevent passengers who appear sick from boarding and to treat all bodily fluids “as though they are infectious.”

• A U.S. Department of Transportation rule permits airlines to deny boarding to air travelers with serious contagious diseases that could spread during flight, including travelers with possible Ebola symptoms. This rule applies to all flights of U.S. airlines, and to direct flights (no change of planes) to or from the United States by foreign airlines.
• Cabin crew should follow routine infection control precautions for onboard sick travelers. If in-flight cleaning is needed, cabin crew should follow routine airline procedures using personal protective equipment available in the Universal Precautions Kit. If a traveler is confirmed to have had infectious Ebola on a flight, CDC will conduct an investigation to assess risk and inform passengers and crew of possible exposure.
• Hand hygiene and other routine infection control measures should be followed.
• Treat all body fluids as though they are infectious.

The CDC’s alarming warnings come as some West African leaders contemplate the complete collapse of their countries. Speaking to The Independent on Sunday, Liberian Information Minister Lewis Brown warned that the West has failed to properly appreciate the scope of the epidemic and the repercussions for the region.

“People need to understand, what we are dealing with has the potential to collapse our three countries,” he said of the nations of Liberia, Guinea, and Sierra Leone.

In Sierra Leone, where nearly 600 have died since the start of the outbreak, a national three-day lockdown has just been lifted. Authorities, who forced the public to remain indoors for days, found only 92 bodies and just over 50 new cases of the disease over the course of the lockdown. Officials said they considered the lockdown a success.