WHEN Jenette Torres Odena's 3-year-old son fell ill days after receiving a jab as part of a Philippine vaccination drive, his photograph spread on Facebook alongside claims the inoculation had killed him.

Doctors found no link between the boy's condition and the measles-rubella vaccine, and he went on to fully recover, but by then his image had appeared in anti-vaccine videos viewed hundreds of thousands of times.

"I felt like crying," Odena said. "I kept praying for my son to recover, and suddenly, they were killing him on Facebook."

The videos were part of a wave of misinformation that accompanied a child vaccination campaign this year that saw more than seven million Filipinos inoculated. Some 230,000 declined the jab.