LONDON (AP) — Former U.S. President Jimmy Carter will make a rare address to Britain's House of Lords on Wednesday to discuss his work to eradicate Guinea worm disease.

The 91-year-old ex-president has helped lead the successful campaign against the disease since 1986.

His office says the eradication of the painful disease spread by contaminated water is now within reach, with just 22 cases reported last year. There were an estimated 3.5 million cases each year when the Carter Center started its work to curtail the disease.

The former president's office said Saturday he will take questions after the talk and encouraged people to submit questions via Twitter to #askJimmyCarter.

Carter said in December that he is cancer free after receiving treatment for liver cancer that had spread to his brain.