This study investigates the emotional dynamics and social connections of Chinese and American populations during the COVID-19 pandemic using social media data from Weibo (China) and Reddit/X (U.S.). It analyzes the temporal evolution of anxiety, anger, sadness, and positive emotions across four phases: baseline, warning, isolation, and normalization. The study also examines the role of family, collective, and country social connections in moderating the relationship between COVID-19 cases and emotional expression. Findings reveal significant cross-cultural differences in emotional responses and the types of social connections emphasized, shaped by cultural values (collectivism vs. individualism) and time orientations (future-focused vs. present-focused).

L. Lu, J. Xu, J. Wei, F.L. Shi, X.L. Fang