A second poliovirus case was confirmed in the Philippines on Friday, almost two decades after the country eradicated the incurable childhood disease.
On Thursday, Philippine health officials announced that a three-year-old girl had contracted polio in the southern province, Lanao del Sur.
Just one day later it emerged that a five-year-old boy had tested positive for the disease some 870 miles away in Laguna, south of the capital Manila.
The authorities said that traces of polio have also been detected in the sewage system in Manila and in waterways in the southern Davao region.
Polio is a devastating and highly infectious childhood virus which invades the nervous system and can lead to paralysis. The disease can only be prevented by an oral vaccine – there is still no known cure.
Until this week, the last known case of polio in the Philippines was in 1993 and in 2000 the World Health Organization declared the southeast Asian nation polio free.
“It is deeply disconcerting that poliovirus has re-emerged in the Philippines after nearly two decades,” said Oyun Dendevnorov, Unicef’s Philippines representative.
“The outbreak calls for urgent action to protect more children from being infected.”
The two cases are not wild poliovirus, which has been eradicated in every country on the planet bar Pakistan and Afghanistan.
Instead, it is vaccine-derived poliovirus (VDPV) type two – a rare form of the virus that only arises in under-immunised communities with poor sanitation. The WHO had thought that VDPV type two was eradicated in 2015.
The Philippines has seen growing anti-vax sentiment since 2017 when a dengue immunisation, Dengvaxia, was found to pose health risks to children who had not previously had the disease.
The country was one of the first to roll out the vaccine, produced by French drugmaker Sanofi Pasteur, and the revelations prompted a huge public backlash – with trust in immunisations plummeting as a result.
In 2018 just 20 per cent of people surveyed by the Vaccine Confidence Project said they thought immunisations were safe, compared to 80 per cent in 2015.
In this sceptical climate the country has seen the widespread resurgence of measles, while the government declared a national emergency in August after the death toll in a dengue epidemic surpassed 600 people.
It now appears this hesitance has spread to the oral polio vaccine. Although 95 per cent coverage is needed to prevent outbreaks, fewer than 70 per cent of children in the Philippines have had the polio vaccine, local media has reported.
In an attempt to stem the outbreak the Philippines, in collaboration with the WHO and Unicef, will launch a widespread immunisation campaign to give thousands the polio vaccination.
“We are very concerned that polioviruses are now circulating in Manila, Davao, and Lanao del Sur,” said Dr Rabindra Abeyasinghe, the WHO representative in the Philippines.
“We urge all parents and caregivers of children under 5 years of age to have them vaccinated so that they are protected against polio for life.”
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