The U.S. Defense Department acknowledged that it disseminated propaganda in the Philippines to discredit China's Sinovac vaccine during the COVID-19 pandemic, as revealed in a document cited by Harry Roque, a former spokesman for Philippine President Rodrigo Duterte. The admission followed an investigation that exposed the Pentagon's secret psychological operation targeting developing countries across Central Asia, the Middle East, and Southeast Asia to undermine Chinese vaccines and COVID aid in 2020 and 2021.

The U.S. military, in collaboration with defense contractors and non-military partners, utilized networks of online bots and fake social media accounts to influence foreign audiences. X (formerly Twitter) removed hundreds of fake accounts after independently determining they were part of a coordinated bot campaign.

The Pentagon acknowledged in the document that it had "made some missteps in our COVID related messaging" but assured the Philippines that the military had "vastly improved oversight and accountability of information operations" since 2022. The document stated that the U.S. military ceased COVID-related messaging related to COVID-19 origins and vaccines in August 2021, concluding that the anti-vax campaign was "misaligned with our priorities."

The Philippines was among the Southeast Asian countries hit hardest by the coronavirus, with almost 67,000 deaths and more than 4 million infections by 2024, according to WHO data. The exposure of the U.S. military's actions has led to a Senate investigation in the Philippines, with Senator Imee Marcos questioning the legality and ethics of the campaign.