Serological reactivity of inactivated SARS-CoV-2 vaccine based on an S-RBD neutralizing antibody assay.

OBJECTIVES: This study aimed to explore the regularity of S-RBD domain antibody reactivity after immunization with inactivated SARS-CoV-2 vaccine and evaluate the effect of this vaccine on the immune response. DESIGN OR METHODS: Venous blood samples were collected from 1156 healthcare workers who participated in the phase III clinical trial of the SARS-CoV-2 inactivated vaccine. The S-RBD domain antibody levels in the serum were detected by ELISA 14 days after the first and second active immunization, respectively. RESULTS: The positive rates after inoculation of the first and second vaccination of S-RBD domain antibody against SARS-CoV-2 were 28.03% and 86.76%, respectively. The mean inhibition rate of S-RBD domain antibody against positive samples was 57.18 ± 18.87% after the second vaccination at 14 days. Sex and age had no effects on the positive rate. The positive rate was decreased in the high BMI group. Single-factor logistic analysis showed that there was no significant correlation between age and positive rate. BMI was negatively correlated with the positive rate. CONCLUSIONS: After 2 immunizations, the positive rate of SARS-CoV-2 S-RBD domain antibody was high, and the vaccine had good immunogenicity. The improvement of the immune strategy should focus on the effects of BMI and other factors.

The Effect of Social Media Use on Depressive Symptoms in Older Adults with Self-Reported Hearing Impairment: An Empirical Study.

Older people with hearing impairment are more likely to develop depressive symptoms due to physical disability and loss of social communication. This study investigated the effects of social media on social relations, subjective aging, and depressive symptoms in these older adults based on the stimulus-organism-response (S-O-R) framework. It provides new empirical evidence to support improving the mental health and rebuilding the social relations of older people. A formal questionnaire was designed using the Wenjuanxing platform and distributed online through WeChat; 643 valid questionnaires were received from older people with self-reported hearing impairments, and SmartPLS 3.28 was used to analyze the data. The results show that (1) social media significantly impacts the social relations of older people with hearing impairment (social networks, ß = 0.132, T = 3.444; social support, ß = 0.129, T = 2.95; social isolation, ß = 0.107, T = 2.505). (2) For these older people, social isolation has the biggest impact on their psychosocial loss (ß = 0.456, T = 10.458), followed by the impact of social support (ß = 0.103, T = 2.014); a hypothesis about social network size was not confirmed (ß = 0.007, T = 0.182). Both social media (ß = 0.096, T = 2.249) and social support (ß = 0.174, T = 4.434) significantly affect the self-efficacy of hearing-impaired older people. (3) Both subjective aging (psychosocial loss, ß = 0.260, T = 6.036; self-efficacy, ß = 0.106, T = 3.15) and social isolation (ß = 0.268, T = 6.307) significantly affect depressive symptoms in older people with hearing impairment. This study expands the theories of social media aging cognition, social support, and social networks and can provide practical contributions to the social media use and mental health of special persons 60 years and older.