Immunogenicity and reactogenicity of heterologous prime-boost vaccination with inactivated COVID-19 and ChAdOx1 nCoV-19 (AZD1222) vaccines, a quasi-experimental study.

The global supply of COVID-19 vaccines has been limited, and concerns have arisen about vaccine supply chain disruptions in developing countries. Heterologous prime-boost vaccination, which involves using different vaccines for the first and second doses, has been proposed to enhance the immune response. We aimed to compare the immunogenicity and safety of a heterologous prime-boost vaccination using an inactivated COVID-19 vaccine and AZD1222 vaccine with that of a homologous vaccination using AZD1222. This pilot involved 164 healthy volunteers without prior SARS-CoV-2 infection aged 18 years or older assigned to receive either the heterologous or homologous vaccination. The results showed that the heterologous approach was safe and well-tolerated, although the reactogenicity of the heterologous approach was higher. At 4 weeks after receiving the booster dose, the heterologous approach elicited a non-inferior immune response compared to the homologous approach in neutralizing antibody and cell-mediated immune response. The percentage of inhibition was 83.88 (79.72-88.03) in the heterologous and 79.88 (75.50-84.25) in the homologous group, a mean difference of 4.60 (-1.67-10.88). The geometric mean of interferon-gamma was 1072.53 mIU/mL (799.29-1439.18) in the heterologous group and 867.67 mIU/mL (671.94-1120.40) in the homologous group, a GMR of 1.24 (0.82-1.85). However, the binding antibody test of the heterologous group was inferior to the homologous group. Our findings suggest that the use of heterologous prime-boost vaccination with different types of COVID-19 vaccines is a viable strategy, especially in settings where vaccine supply is limited or where vaccine distribution is challenging.

Prevalence and associated factors influencing depression in older adults living in rural Thailand: A cross-sectional study.

AIM: Depression is a major disease burden in Thailand. In rural areas, young adults will leave home to work in cities, and older adults are left behind. Loneliness and comorbidities can lead to depression in older adults. The present study aimed to evaluate the prevalence and associated factors for geriatric depression. METHODS: A cross-sectional study was carried out. Questionnaires including the Thai Geriatric Depression Scale and family relationship were obtained by healthcare professions by face-to-face interviews of 584 older people aged ≥60 years in Ban Nayao community, Chachoengsao Province, Thailand. Geriatric depression can be defined as depressive syndromes that arise in adults aged ≥60 years. We excluded those who had visual or auditory disabilities or did not pass the Thai Mini-Mental Status Examination. The prevalence and associated factors for geriatric depression were obtained. Associated factors were analyzed by multivariate logistic regression. RESULTS: A total of 433 older people were eligible. The prevalence of geriatric depression was 18.5%. Of the participants, 54.1% lived in an imbalanced family type. Multivariate analysis showed the significance for female sex (adjusted OR 2.78, 95% CI 1.54-7.49, P = 0.01), illiteracy (adjusted OR 2.86, 95% CI 1.19-6.17, P-value 0.04), current smoker (adjusted OR 4.25, 95% CI 2.12-10.18, P = 0.009) and imbalanced family type (low attachment, low cooperation and poor alignment between each member; adjusted OR 4.52, 95% CI 2.14-7.86, P < 0.001) as risk factors for depression. CONCLUSIONS: The prevalence of geriatric depression in rural Thailand is high. Imbalanced family type is an important risk factor for geriatric depression in the rural community. Geriatr Gerontol Int 2019; 19: 1248-1253.