By Shelby Lin Erdman
(CNN) -- Liberian President Ellen Johnson Sirleaf said Monday that the situation over the massive Ebola outbreak in her country "remains grave."
"Our health delivery system is under stress. The international community couldn't respond quickly," Johnson Sirleaf told CNN's Nima Elbagir in an interview.
Liberia is one of three nations, including Guinea and Sierra Leone, at the center of the deadliest outbreak of Ebola in history. More than 1,500 people have died from the highly infectious virus since March.
The World Health Organization has confirmed more than 3,000 cases and says the outbreak is still accelerating across West Africa.
But Johnson Sirleaf sounded hopeful. She said conditions are slowly improving and that the world is responding to the epidemic, realizing the catastrophe that could unfold if the virus were to spread beyond Africa's borders.
She warned a bigger response is needed to prevent that.
"People now don't see this as a Liberia or West Africa crisis. It could easily become a global crisis."
Johnson Sirleaf said the solution is for the global community to work in partnership with the affected nations to help them fight Ebola.
"We need that hope, we need that assistance. We need for the Liberians to know that this war can be won," Johnson Sirleaf said.
The West African nation of Senegal confirmed its first Ebola case last week, one week after closing its border with Guinea.
Senegal is the fifth country in the region to report the Ebola virus.
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