Do conspiracy theories circulating in the media or their debunking affect people’s trust in the media?

The COVID-19 pandemic has fostered an unprecedented number of conspiracy theories about the virus and the vaccine against the disease. Current research has tried to make sense of the effects of conspiracy narratives and debunking them in both mainstream and social media. However, the effect of such narratives or their debunking on media trust has not been investigated to date. By means of a 2 × 2 experimental design (N = 945) in Romania, we investigate how mainstream and social media content containing conspiracy theories about vaccination against COVID-19 and debunking them influence people’s trust in both mainstream and social media. People’s own beliefs in such narratives are used as moderators of these effects. Findings show that only the debunking content circulating in mainstream media decreases people’s trust in both mainstream and social media, and only for people exhibiting high levels of belief in conspiracy theories, that is only when people are exposed to counter-attitudinal content. Implications for stakeholders are discussed.