Before revision:  We find that messages about COVID-19 are more likely to come from high quality sources , with clearer provenance, when compared to other health topics. Low-credibility sourceswere less likely to post about COVID-19, with the important exception of state-sponsored propaganda outlets on Twitter. Finally, a known conspiracy theory was more likely to be ``laundered'' through social media platforms than low-credibility news sources .
After revision:  We find that messages about COVID-19 are more likely to come from high quality sources , and to news with intermediate credibility, were shared more often, on average, than links to non-credible sources. These results suggest that more ambiguous forms of misinformation about COVID-19 may be more likely to be ``laundered'' through social media platforms than low-credibility news sources .