The World Health Organisation (WHO) has declared a polio outbreak in Papua New Guinea.
Samples of the highly infectious virus were found in two healthy children during a routine screening in Lae, a coastal city in the country's north east.
"We have to make maximum effort to get 100% [vaccination] coverage," Dr Sevil Huseynova, WHO's representative in Papua New Guinea, said at a media conference on Thursday, according to the BBC.
Papua New Guinea was said to be polio-free since 2000, until an outbreak in 2018, which was contained within the same year.
The latest cases were found to be carrying a virus strain genetically linked to one circulating in Indonesia. Papua New Guinea shares a border with Indonesia's easternmost Papua province.
Health Minister Elias Kapavore has vowed to achieve 100% polio immunisation in the country by the end of this year.
"There is no excuse... Polio is a serious disease," he said.
The WHO, UN's children agency Unicef and Australia's government are supporting Papua New Guinea in its rollout of vaccines.
The ongoing campaign will target children aged 10 and below and is expected to reach around 3.5 million people.
The WHO says wild poliovirus type 2 was eradicated in 1999 and type 3 was wiped out in 2020. As of 2022, there were just two countries still impacted by wild poliovirus type 1 — Pakistan and Afghanistan, according to Australian Broadcasting Corporation.