Watch the full interview with Dr. Peter Piot on “Fareed Zakaria GPS,” this Sunday at 10 a.m. and 1 p.m. ET on CNN

(CNN) — The current Ebola outbreak is “running much faster” than the international response to it, the co-discoverer of the virus said Thursday.

“This is the first Ebola epidemic where entire nations are involved, where big cities are affected,” Peter Piot, a microbiologist and a former undersecretary general of the United Nations, told Global Public Square host Fareed Zakaria. “And I continue to be worried that the response to the epidemic is really running behind the virus.”Aid workers train to

According to the World Health Organization’s latest update, there have been almost 9,000 confirmed and suspected cases, with almost 4,500 deaths. However, the WHO warned there could be as many as 10,000 new cases per week in Guinea, Liberia and Sierra Leone by the end of this year.

Piot, a member of the team that discovered the virus in 1976 in what is now the Democratic Republic of Congo, made headlines earlier this month when he told The Guardian newspaper he feared an “unimaginable catastrophe” if the virus became lodged in a mega-city such as Lagos.

“The three countries that are affected are being totally destabilized, not only in terms of people who are killed by Ebola — their families, the orphans that now are coming up because the parents died — but the economy has come to a standstill,” Piot said Thursday, speaking from Oxford.

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