Trajectories of public psycho-behavioural responses relating to influenza A(H7N9) over the winter of 2014-15 in Hong Kong

Objective: To explore trajectories of public psycho-behavioural responses over one influenza A(H7N9) epidemic wave, and examine the interplays among social norm influence, disease worry and protective behaviours. Methods: Participants were 464 adults who completed the baseline and at least two follow-up assessments on their H7N9-related Perceived Susceptibility, Perceived Severity, Perceived Efficacy, Worry, Social Norms influence and Protective Behaviours in a five-phase longitudinal survey over one H7N9 epidemic wave. Latent growth modelling (LGM) identified trajectories of these psycho-behavioural responses while multi-process LGM examined the inter-relationships among trajectories of Social Norms influence, Worry and Protective Behaviours. Results: Trajectories of Perceived Susceptibility, Worry, Social Norms and Protective Behaviours increased initially but declined as the epidemic decayed, while Perceived Severity increased linearly and Perceived Efficacy remained stable across the epidemic. Change in Social Norms influence was significantly associated with change in Worry (beta = 0.65) which was significantly associated with change in Protective Behaviours (beta = 0.62). Conclusion: The public's threat appraisal but not efficacy appraisal may have been well-informed by epidemic-related information. Social Norms may be important contributors of public emotional response to an epidemic. Communication via social networks during an epidemic could be important for regulating public emotional response and guiding their behavioural change.