A cross-sectional study conducted in China during the early stages of the COVID-19 outbreak found high prevalence of mental health problems, particularly depression and anxiety, among the general population. The study involved 4872 participants aged 18 and older from 31 provinces. Mental health was assessed using the Chinese version of the WHO-5 Well-Being Index for depression and the GAD-7 for anxiety. Results showed that 48.3% of participants had depression, 22.6% had anxiety, and 19.4% had both. Over 80% of participants frequently exposed themselves to social media during the outbreak. After controlling for various factors, frequent social media exposure was positively associated with higher odds of anxiety and combined depression and anxiety (CDA). The study highlights the need for increased attention to mental health issues during public health emergencies, especially in combating "infodemics" caused by misinformation. The findings suggest that frequent social media use may contribute to mental health problems, possibly due to information overload and the spread of negative emotions through social networks. The study also notes that individuals from Hubei province, the epicenter of the outbreak, faced higher odds of anxiety, indicating the impact of direct exposure to the public health emergency. The study acknowledges limitations, including the cross-sectional design and potential response bias. Overall, the study underscores the importance of addressing mental health during public health crises and the need for effective communication strategies to manage misinformation.A cross-sectional study conducted in China during the early stages of the COVID-19 outbreak found high prevalence of mental health problems, particularly depression and anxiety, among the general population. The study involved 4872 participants aged 18 and older from 31 provinces. Mental health was assessed using the Chinese version of the WHO-5 Well-Being Index for depression and the GAD-7 for anxiety. Results showed that 48.3% of participants had depression, 22.6% had anxiety, and 19.4% had both. Over 80% of participants frequently exposed themselves to social media during the outbreak. After controlling for various factors, frequent social media exposure was positively associated with higher odds of anxiety and combined depression and anxiety (CDA). The study highlights the need for increased attention to mental health issues during public health emergencies, especially in combating "infodemics" caused by misinformation. The findings suggest that frequent social media use may contribute to mental health problems, possibly due to information overload and the spread of negative emotions through social networks. The study also notes that individuals from Hubei province, the epicenter of the outbreak, faced higher odds of anxiety, indicating the impact of direct exposure to the public health emergency. The study acknowledges limitations, including the cross-sectional design and potential response bias. Overall, the study underscores the importance of addressing mental health during public health crises and the need for effective communication strategies to manage misinformation.