Papua New Guinea's polio outbreak has claimed its first fatality, authorities confirmed this week, after a 9-month-old baby died in Enga Province.
The boy died in hospital after the virus paralysed the muscles around his lungs, Luo Dapeng, the World Health Organisation's representative in PNG said.
"This 9-month boy ... had initial symptoms in the beginning of August," said Dr Luo. "At the beginning of September he was confirmed to be polio cases. Unfortunately, a few days after confirmation, he passed away on 8 September."
PNG became one of the few countries in the world to see polio return in June, 18 years after it was first eradicated.
Since then, 14 children - ten of them under 5-years-old - have been confirmed to have the virus in five provinces, and all of them have some kind of paralysis.
Since the outbreak was confirmed, authorities have launched a massive effort to both contain the outbreak, and vaccinate more than three million children across the country.
The outbreak is vaccine-derived polio, where the weakened form of the virus used in vaccinations mutates and spreads.
It's able to spread in conditions of poor sanitation and where few children are immunised against polio, which is the case in PNG, where rates have fallen to as low as 30 percent in some areas.
Dr Luo said the campaign was a massive undertaking, with 9,000 WHO workers fanned out across the country and logistical hubs in every province.
But initial signs show it is working.
"Fortunately, all the cases we've confirmed so far are [from] before the vaccination campaign," said Dr Luo. "So that's good news."
However, Dr Luo was under no illusions as to how hard it would be to eradicate polio from Papua New Guinea - again.
Polio returned after vaccination campaigns were largely stopped as a result of budget cuts and a lackadaisical approach to immunisation after the country was first declared polio-free in 2000.
Dr Luo said the WHO was trying to work with the PNG government to make sure that, first, polio is again eradicated and, second, that it stays away through a routine vaccination programme.
"We want to set up a special immunisation programme to give specific priority to ensure there's routine immunisation in place," he said.
"Of course the WHO is here to support the government, to help the government, to have a routine immunisation programme in place to protect children from this kind of disaster which we see in the country now."