Are COVID-19 conspiracies a threat to public health? Psychological characteristics and health protective behaviours of believers

We tested the link between COVID-19 conspiracy theories and health protective behaviours in three studies: one at the onset of the pandemic in the United Kingdom (UK), a second just before the first national lockdown, and a third during that lockdown (N = 302, 404 and 399). We focused on conspiracy theories that did not deny the existence of COVID-19 and evaluated the extent to which they predicted a range of health protective behaviours, before and after controlling for psychological and sociodemographic characteristics associated with conspiracy theory belief. COVID-19 conspiracy beliefs were positively correlated with beliefs in other unrelated conspiracies and a general conspiracy mind-set, and negatively correlated with trust in government and a tendency towards analytical thinking (vs. intuitive thinking). Unexpectedly, COVID-19 conspiracy believers adhered to basic health guidelines and advanced health protective measures as strictly as non-believers. Conspiracy believers were, however, less willing to install the contact-tracing app, get tested for and vaccinated against COVID-19, and were more likely to share COVID-19 misinformation—all of which might undermine public health initiatives. Study 3 showed conspiracy theory believers were less willing to undertake health protective behaviours that were outside of their personal control, perceiving these as having a negative balance of risks and benefits. We discuss models explaining conspiracy beliefs and health protective behaviours, and suggest practical recommendations for public health initiatives.