"We need gradual eradication," said Mr. Tunubalá.
chief of polio eradication, said he was still "very optimistic" that eradication could be achieved.
But in the end, "it's all about poverty eradication," said Ms. Hibbard.
It was the beginning of six decades of sustained eradication, said Luis Escoto, the WHO representative in Paraguay.
"Defra is continuing to fund ongoing work this year of £200,000 to enable the food and environment research agency to carry out eradication," said a spokeswoman in an email.
"The whole project is carrot and stick: they see the spray planes and sign up for manual eradication," says Anne Patterson, the United States' ambassador in Bogota.
Advocates of eradication say that it is a worthy goal to root out forever even one source of human misery, and that an unpredictable world offers brief opportunities to do so.
Now "may be the last chance to finish the job" of polio eradication, said Dr. Bruce Aylward, a polio expert, because many donors and countries are tired of investing in the effort.
In Pointe Noire, the port city where most of the cases are concentrated, "We've got two hospitals with hundreds of paralyzed people and many dead," Dr. Bruce Aylward, the W.H.O.'s director of global polio eradication, said in an interview from Geneva.
