New Delhi, Nov. 22 -- The World Health Organization has declared Indonesia's polio outbreak officially over, following nearly three years of intensive response efforts, officials said Friday.

Indonesia has remained largely polio-free as the highly contagious disease was declared eliminated in the country in 2014. But eight years later, an outbreak emerged in the country's conservative Aceh province, prompted by a dangerous combination of consistently low routine immunization and unhealthy environmental conditions. In 2021, only 50.9% of infants born in Aceh received polio vaccination.

Officials say that polio immunization rates in Aceh are well behind the rest of the country, with efforts hampered by widespread disinformation that the v...