More people have died from measles in the Philippines so far this year than the entire 2018, with experts warning about 2.6 million children remain at risk in the country.

The International Federation of Red Cross and Red Crescent Societies (IFRC) says the outbreak has killed 261 people this year alone and most of the victims were children aged under five.

This compares with 202 total deaths in 2018 which translates to a 547 percent increase on the previous year.

“It is completely unacceptable that children are still dying from measles in 2019,” said Richard Gordon, chairman and CEO of the Philippines Red Cross.

The IFRC, with the Philippines’ Department of Health, is now aiming to immunise all unvaccinated children across seven of the “hardest-hit regions” over the next 12 months.

“We are drawing on the skills and dedication of our two million Red Cross volunteers to go door-to-door and neighbourhood-to-neighbourhood,” Gordon added.

Filipinos’ confidence in vaccines fell dramatically after a 2014 scandal involving a new dengue fever vaccine, Dengvaxia.

Those with no history of dengue were at a greater risk of developing a more severe form of the disease after having the vaccination.

World Health Organisation representative to the Philippines, Gundo Weiler, said the country was now suffering from a measles outbreak “every three to four years,” pointing to large-scale outbreaks in 2011 and 2014.

As many as 20 000 cases were recorded in the last major outbreak, which Weiler said was comparable in magnitude to the latest episode, which has infected more than 1 500 people in recent weeks.

The IFRC is now working to restore confidence in vaccines.