Clinical characteristics of patients infected with 2019 novel coronavirus Omicron variant in Zhuhai City / 中华传染病杂志

ABSTRACT

Objective:To explore the clinical characteristics of patients infected with 2019 novel coronavirus (2019-nCoV) Omicron variant in Zhuhai City.Methods:A retrospective study was conducted to compare the clinical characteristics of patients infected with 2019-nCoV Omicron variant (Omicron variant group, 39 cases) from January 13 to January 25, 2022, and those infected with 2019-nCoV non-Omicron variant (non-Omicron variant group, 98 cases) from January 17 to February 17, 2020, in the Fifth Affiliated Hospital of Sun Yat-sen University. Statistic methods were used by Mann-Whitney U test, chi-square test and Fisher exact probability test. Results:Among adults, the age of 21 patients in Omicron variant group was younger than that of 93 patients in non-Omicron variant group (34.0(26.0, 40.5) years vs 50.0(36.0, 62.0) years, Z=-3.81, P<0.001). Patients with underlying diseases in Omicron variant group were fewer than those in non-Omicron variant group (4.8%(1/21) vs 31.2%(29/93), χ2=6.17, P=0.013). The clinical classification of the Omicron variant group was mainly mild (71.4%(15/21)) or common type (28.6%(6/21)), while the non-Omicron variant group was dominated with common type (57.0%(53/93)) and severe type (23.7%(22/93)), and the clinical classification of the two groups had statistically difference ( χ2=31.79, P<0.001). The time of positive nucleic acid in Omicron variant group was longer than that in non-Omicron variant group (14.0(10.5, 16.5) d vs 8.5(4.0, 12.0) d, Z=-3.56, P<0.001). The proportion of pneumonia in Omicron variant group was less than that in non-Omicron variant group (28.6%(6/21) vs 86.0%(80/93), χ2=30.52, P<0.001). Differences were all statistically significant. There was no significant difference of the clinical characteristics in pediatric patients, but the proportion of children infected with 2019-nCoV Omicron variant was significantly higher than that infected with 2019-nCoV non-Omicron variant (46.2%(18/39) vs 5.1%(5/98), χ2=33.65, P<0.001). Conclusions:Adults infected with 2019-nCoV Omicron variant in Zhuhai City present with milder clinical symptoms, less proportion of pneumonia, but the time of positive nucleic acid is longer. The clinical characteristics of children infected with 2019-nCoV Omicron variant are not specific, while the proportion of children infected with 2019-nCoV Omicron variant is significantly higher.