Abstract:

Objective To explore the clinical characteristics of the B.1.617.2 (Delta) variant of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) of shipmates, and the protective effect of SARS-CoV-2 vaccines. Methods From August to November 2021, five imported cases of Delta variants of SARS-CoV-2 and 17 shipmates were enrolled, who all visited fixed point isolation endemic area of the First People's Hospital of Fangchenggang, and divided into the vaccinated group (n=10) and the unvaccinated group (n=12), the clinical data of the two groups were retrospectively analyzed. Results Among the 22 shipmates, there were 14 cases of SARS-CoV-2 infection, with the infection rate of 63.6%; the unvaccinated group was more common (P<0.05). Of 14 cases, 12 had clinical symptoms (fever, olfactory and taste loss, cough, chest tightness, expectoration, fatigue, and body aches) except for 2 asymptomatic SARS-CoV-2 infections. The difference was not statistically significant in fever duration between the vaccinated group and the unvaccinated group ([7.62±2.32] days vs [6.25±2.50] days, [P=0.368], respectively); the negative conversion time of SARS-CoV-2 nucleic acid in the unvaccinated group and the vaccinated group was (65.75±25.81) days and (44.00±28.32) days, respectively, and with no statistically significant difference (P=0.211). Conclusion The present data showed that domestic vaccine has a protective effect against the Delta variant of SARS-CoV-2. Both the prolonged time of negative conversion and whether or not vaccination have no correlation.

Key words: COVID-19, COVID-19 vaccines, clinical characteristics