So far, these messages have yet to break through to a wider audience, mostly staying within Russian- and Chinese-friendly audiences online, particularly in countries like Italy, Spain and Greece.

But as the global crisis grows at pace, such efforts — both from state-backed groups and domestic EU actors — are linking the coronavirus pandemic with existing misinformation themes, including the targeting of migrants, minority groups and the long-term credibility of the EU, according to the authors of the update.

"In the EU and elsewhere, coordinated disinformation messaging seeks to frame vulnerable minorities as the cause of the pandemic and to fuel distrust in the ability of democratic institutions to deliver effective responses," the officials wrote in their analysis. "Some state and state-backed actors seek to exploit the public health crisis to advance geopolitical interests, often by directly challenging the credibility of the European Union and its partners."

Both Russia and China have rejected accusations that they have spread false reports and disinformation online.

In response to the public health crisis, EU officials and executives from Google, Facebook and Twitter have tried to clamp down on the worst offenders, with Ursula von der Leyen, the European Commission president, urging both tech companies and the public to do more to stop the spread of disinformation online.

Confronted with demands for action, social media giants have beefed up their response to the crisis, including promoting official advice, removing harmful material and using artificial intelligence tools to track false reports. Still, many policymakers remain unsatisfied, and misinformation remains rife on these digital platforms.

"Those spreading disinformation harm you," von der Leyen said in an online video statement on Tuesday. "Disinformation can cost lives."

In recent weeks, China and Russian had attempted to undermine Europe's response to the crisis, according to the analysis. That included promoting messages, both within the 27-country bloc, as well as the Western Balkans, North America and elsewhere, that the EU was not tackling the pandemic, that it was betraying its core values in the region's response and that Moscow and Beijing were the only ones providing a robust strategy to combat COVID-19.

Yet despite these state-backed initiatives, most online falsehoods about the coronavirus still originate from average EU citizens looking for advice, guidance and support from others on social media, according to several independent disinformation experts who were not connected to the EU's latest analysis.