Days after returning from West Africa, Director of the Centers for Disease Control and Prevention Thomas Frieden opened a press conference with a sobering admonition about the effort to contain the Ebola epidemic to West Africa: “The window is closing.”

In an impassioned call to action, he urged American doctors, nurses, and health care professionals to join Africa in its fight. “This isn’t just the countries’ problem,” he said. “It’s a global problem.” With vivid detail, Frieden painted a gruesome picture of overcrowded isolation centers in Liberia, Sierra Leone, and Guinea, where health care workers are struggling to keep up with “basic care.” He mentioned deficiencies not only in the number of doctors, nurses, and health managers available, but the protective gear needed to keep them safe. Without an immediate change in the current landscape, he said, the worst is yet to come. “The level of outbreak is beyond anything we’ve seen—or even imagined,” Frieden said.

At one particular 35-bed facility, Frieden described the chilling sight of more than three-dozen Ebola patients without beds, left with no other place to fight their infections but the floor. The health care workers, too, face “distressing” conditions. “Roasting hot” personal protective gear including robes, masks, boots, and goggles, make simply drawing an IV a near impossible task. “It is very difficult to move…sweats pours into goggles, [the health workers] see the enormous need but the great risk, too,” he said.

But even more alarming than the disturbing images, was the lack of outside support. “The most upsetting thing I saw was what I didn’t see,” he said. “No data from countries where it’s spreading, no rapid response teams, no trucks, a lack of efficient management,” he said. “I could not possibly overstate the need for an urgent response.”

Outside of the isolation centers, the burial process poses its own unique challenges. With the bodies of Ebola victims even more contagious after death, those who handle them are put at great risk of infection. In his travels, Frieden recalled meeting with young men of a burial team working well past 10 p.m. in full protective gear to bury Ebola casualties. After close to 15-hours of grueling work wrapping the bodies, sanitizing them with bleach, and lowering them six feet into the ground, many return home to families who have ostracized them for fear they carry the infection, forcing them to sleep outside on the ground.

Not burying these bodies properly, Frieden says, poses even more of a threat to the community. When he asked how an Ebola intelligence officer was in the elevator one day in West Africa, he was saddened to watch her respond instantly: “Terrible.” Just days before, the officer told him, 19 bodies of Ebola victims were left lying outside with few men to bury them. The next day, over 35 new cases had developed.

In another harrowing scene, Frieden described meeting with a 22-year-old girl who had been infected with Ebola in Liberia. Fatima, as he called her, had been caring for a young family member suffering with diarrhea and vomiting, when she herself contracted the disease. Even more traumatizing than her own battle with the infection, from which she eventually recovered, was watching her older brother lose his battle. “When I asked her what was the hardest thing…she broke into tears and said she was next to her brother when he died,” said Frieden. “She was horrified by the symptoms he was having—and terrified that she was next. That’s the reality the people in this regions are dealing with every single day.”

In urging Americans and other global health workers to get involved, he stressed that if proper precautions are taken, the work is not dangerous. The CDC director used his own recent experience in West Africa as proof that medical professionals can remain safe. “Swaddled in protective gear” he was “sprayed down with bleach every step of the way” to ensure he was safe. “Turning this around will require lots of effort and highly specialized people. Doctors, nurses, health administers, emergency managers. People who can stay for three months or more,” Frieden said. “The longer you are there the more effective you can be.”

Frieden also called on companies in the private sector to step up their response, saying that that the U.S. Embassy has reached out to corporations who have facilities in the area. Firestone, whose West African rubber factory is the largest in the world, built its own isolation center for the 73 contacts in their company. Eleven ended up contracting the disease, all of which were treated at Firestone’s own facility. “I think it’s in their interest sooner rather than later to get involved,” he said of companies in the area.

When reporters probed Frieden about potential vaccines, he managed expectations of finding a viable treatment option in enough time. “Vaccines have begun clinical trials, but we don’t have large quantities, and even if they’re safe, we have to figure out if they are effective.” The supply of one treatment known as ZMapp, Frieden confirmed, has been completely exhausted. Making more is “extremely difficult,” and not a viable solution time-wise. “We can hope a vaccine works out, but we can’t count on it,” he said.

Despite the chilling report from his West Africa trip, Frieden “remains confident” the there’s still time to contain the epidemic. “I saw many signs of hope,” he said, praising health care workers working around the clock to contain the disease. “I held a 2-year-old kid who is a survivor. Her parents have died but she’s being raised by family…she’s a symbol of hope,” he said. “The survivors are living proof that you can beat this.”

Frieden ended his talk with a final plea to the international community. “There is nothing mysterious about we need to do,” he said. “The only real question is if we’ll do it fast enough.”

If we don’t, there is no telling how far it will go. “For every day that this continues to spread in West Africa, the likelihood of someone getting infected and transmitting it elsewhere increases,” he said. “As long as Ebola is spreading anywhere, all of us need to be concerned.”