The polio virus has not infected anyone in the two African countries during the last 12 months, leaving only Afghanistan, India, Nigeria and Pakistan as countries where the disease is still classified as endemic, the World Health Organisation said.
"Polio has been endemic in our country for all of recorded history. The best tools of our age finally defeated this enemy, who has been with us from pharaonic times" Egypt's Health Minister Dr Hatim Mustafa al-Gabaly said.
Geneva-based WHO failed to meet its long-standing target of eradicating polio globally by the end of last year after hard-line Islamic clerics in northern Nigeria led an immunisation boycott in 2003.
They claimed the polio vaccine was part of a US-led plot to render Nigeria's Muslims infertile or infect them with Aids.
The Nigerian vaccine boycott was blamed for causing an outbreak that spread the disease across Africa into the Middle East and as far as Indonesia.
But WHO said the disease could be eradicated everywhere but Nigeria in the first six months of this year.
WHO said the success in Egypt and Niger was the result of intense efforts to halt Africa's epidemic by speeding up the introduction of new vaccines into affected areas.
In the last three months of 2005, the number of cases in India and Pakistan also fell by more than half compared to the previous year.
Jonathan Majiyagbe, a former president of Rotary International, who has contributed more than $600 million to eradicate polio said: "To fully exploit these new tools, government commitment in Nigeria must remain high at all levels to ensure that all children are vaccinated."