Director-general of the World Health Organization (WHO) Margaret Chan said Wednesday that she saw no signs of an early end to the Ebola outbreak in West Africa that has killed over 1,300 people since March.

"No one is talking about an early end to the outbreak," Chan wrote in a perspective article in the US journal New England Journal of Medicine. "The international community will need to gear up for many more months of massive, coordinated, and targeted assistance."

Chan said what makes the outbreak so large, so severe, and so difficult to contain is poverty.

"The hardest-hit countries, Guinea, Liberia, and Sierra Leone, are among the poorest in the world," she said. "They have only recently emerged from years of conflict and civil war that have left their health systems largely destroyed or severely disabled and, in some areas, left a generation of children without education."

According to the WHO chief, in these countries, only one or two doctors are available for every 100,000 people, and these doctors are heavily concentrated in urban areas. What's worse, nearly 160 health care workers have been infected, and more than 80 have died. In addition, isolation wards and hospital capacity for infection control are "virtually nonexistent."

The outbreak, the worst in the nearly four-decade history of this disease, was also fueled by high unemployment as people were forced to cross borders to find work. As a result, "the area where the borders of the three countries intersect is now the designated hot zone, where the transmission is intense," Chan wrote.

Chan said fear remains the most difficult barrier to overcome," with people who have had contact with infected persons escaping from the surveillance system, relatives hiding symptomatic family members or taking them to traditional healers, and patients fleeing treatment centers.

She called changing long-standing funeral practices that involve close contact with highly infectious corpses "one urgent priority." In Guinea, 60 percent of Ebola cases have been linked to traditional burials, Chan said.

There are also rumors about Ebola miracle cures. At least two Nigerians have died after drinking salt water, which was rumored to be protective, Chan wrote.

While the situation continues to deteriorate in the hardest-hit countries, the international response to the outbreak has improved over the past two weeks, she said, noting that the framework for a scaled-up response, including the deployment of more medical staff, logisticians, and event managers, is rapidly taking shape.

"The needs are enormous; the prospects for rapid containment are slim," Chan said. "(However,) experience tells us that Ebola outbreaks can be contained, even without a vaccine or cure."