[Clinical features of children and their family members with family clusters of SARS-CoV-2 Omicron variant infection in Shanghai, China: an analysis of 380 cases]. / 上海380例家庭聚集性感染Omicronå˜å¼‚æ ªçš„å„¿ç«¥åŠå ¶å®¶å±žä¸´åºŠç‰¹å¾åˆ†æž.

OBJECTIVES: To study the clinical features and prognosis of children and their family members with family clusters of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant infection under the admission mode of parent-child ward. METHODS: A retrospective analysis was performed on the medical data of 190 children and 190 family members with SARS-CoV-2 Omicron variant infection who were admitted to Shanghai Sixth People's Hospital, the designated hospital for coronavirus disease 2019 (COVID-19), April 8 to May 10, 2022. RESULTS: Both the child and adult groups were mainly mild COVID-19, and the proportion of mild cases in the child group was higher than that in the adult group (P<0.05). Respiratory symptoms were the main clinical manifestations in both groups. Compared with the adult group, the child group had higher incidence rates of fever, abdominal pain, diarrhea, and wheezing (P<0.05) and lower incidence rates of nasal obstruction, runny nose, cough, dry throat, throat itching, and throat pain (P<0.05). Compared with the child group, the adult group had higher rates of use of Chinese patent drugs, traditional Chinese medicine decoction, recombinant interferon spray, cough-relieving and phlegm-eliminating drugs, and nirmatrelvir/ritonavir tablets (P<0.05). Compared with the adult group, the child group had a lower vaccination rate of SARS-CoV-2 vaccine (30.5% vs 71.1%, P<0.001) and a shorter duration of positive SARS-CoV-2 nucleic acid (P<0.05). The patients with mild COVID-19 had a shorter duration of positive SARS-CoV-2 nucleic acid than those with common COVID-19 in both groups (P<0.05). The patients with underlying diseases had a longer duration of positive SARS-CoV-2 nucleic acid than those without such diseases in both groups (P<0.05). CONCLUSIONS: Both children and adults with family clusters of SARS-CoV-2 Omicron variant infection manifest mainly mild COVID-19. Despite lower vaccination rate of SARS-CoV-2 vaccine in children, they have rapid disease recovery, with a shorter duration of positive SARS-CoV-2 nucleic acid than adults, under the admission mode of parent-child ward.

Clinical and psychological status analysis of children and parents infected with familial aggregation omicron variant in Shanghai in parent-child ward.

Aims: To analyze the clinical characteristics, treatment outcomes and sleep psychological problems of children and parents infected with familial aggregation Omicron variants under a parent-child ward treatment mode to provide a theoretical reference for the diagnosis and comprehensive treatment of Omicron variant strains. Methods: The clinical data of 225 children and 230 adult family members admitted were retrospectively collected and analyzed to investigate their clinical characteristics and response to treatments. Results: The proportion of infected adults and children was the same, and the proportion of children with mild disease was higher than that of adults, but the clinical symptoms were milder. The clinical symptoms of fever, nausea, vomiting and wheezing in children were significantly higher than in adults (P < 0.05). In addition, dry pharynx, pharynx itching and pharyngeal pain were lower than in adults (P < 0.05). The time of turning negative in the moderate group was longer than in the mild group, and the time of turning negative in the unvaccinated group was higher than in the vaccinated group (P < 0.05). The Cycle Threshold Value (Ct value) of Open Reading Frame 1ab (ORF1ab) and Nucleocapsid protein (N) gene of children were higher adults. The increase in the rate of Ct value of ORF1ab and N gene in adults treated with Traditional Chinese Medicine (TCM) was significantly higher than in those who underwent symptomatic treatment (P < 0.01). Based on the Children's Sleep Habits Questionnaire (CSHQ)score, we found varying levels of sleep problems in sleeping habits, latency and anxiety, night awakenings and abnormal sleep at all ages (P < 0.05). In the adult group, those with Self-Rating Scale of Sleep (SRSS) scores ≥3 accounted for more than 50% of adults with insomnia, sleep deprivation, sleep instability and early awakening. The proportion of adults with anxiety and depression was 21.3% and 16.4%. Conclusion: Infections in children and adults during this pandemic were mainly associated with familial aggregation infections, and their clinical symptoms were mainly located in the upper respiratory tract. With comprehensive treatment, children became negative faster, vaccination led to faster recovery, and although some patients experienced sleeping and psychological issues, all patients had good prognoses following comprehensive diagnosis under a parent-child ward treatment mode.

Characteristics of transmission routes of COVID-19 cluster infections in Gangwon Province, Korea.

This study investigated the characteristics of transmission routes of COVID-19 cluster infections (⩾10 linked cases within a short period) in Gangwon Province between 22 February 2020 and 31 May 2021. Transmission routes were divided into five major categories and 35 sub-categories according to the relationship between the infector and the infectee and the location of transmission. A total of 61 clusters occurred during the study period, including 1741 confirmed cases (55.7% of all confirmed cases (n = 3125)). The the five major routes of transmission were as follows: 'using (staying in) the same facility (50.7%), 'cohabiting family members' (23.3%), 'social gatherings with acquaintances' (10.8%), 'other transmission routes' (7.0%), and 'social gatherings with non-cohabiting family members/relatives' (5.5%). For transmission caused by using (staying in) the same facility, the highest number of confirmed cases was associated with churches, followed by medical institutions (inpatient), sports facilities, military bases, offices, nightlife businesses, schools, restaurants, day-care centres and kindergarten, and service businesses. Our analysis highlights specific locations with frequent transmission of infections, and transmission routes that should be targeted in situations where adherence to disease control rules is difficult.

Analyses of Confirmed COVID-19 Cases Among Korean Military Personnel After Mass Vaccination.

BACKGROUND: The military was one of the first groups in Korea to complete mass vaccination against the coronavirus disease 2019 (COVID-19) due to their high vulnerability to COVID-19. To confirm the effect of mass vaccination, this study analyzed the patterns of confirmed cases within Korean military units. METHODS: From August 1 to September 15, 2021, all epidemiological data regarding confirmed COVID-19 cases in military units were reviewed. The number of confirmed cases in the units that were believed to have achieved herd immunity (i.e., ≥ 70% vaccination) was compared with the number of cases in the units that were not believed to have reached herd immunity (< 70% vaccination). Additionally, trends in the incidence rates of COVID-19 in the military and the entire Korean population were compared. RESULTS: By August 2021, 85.60% of military personnel were fully vaccinated. During the study period, a total of 174 COVID-19 cases were confirmed in the 39 units. More local transmission (herd immunity group vs. non-herd immunity group [%], 1 [0.91] vs. 39 [60.94]) and hospitalizations (12 [11.01] vs. 13 [27.08]) occurred in the units that were not believed to have achieved herd immunity. The percentage of fully vaccinated individuals among the confirmed COVID-19 cases increased over time, possibly due to the prevalence of the delta variant. Nevertheless, the incidence rate remained lower in military units than in the general Korean population. CONCLUSION: After completing mass vaccination, the incidence rates of COVID-19 infection in the military were lower than those in the national population. New cluster infections did not occur in vaccinated units, thereby suggesting that herd immunity has been achieved in these military units. Further research is needed to determine the extent to which levels of non-pharmacological intervention can be reduced in the future.

Epidemiological and clinical features of SARS-CoV-2 cluster infection in Anhui Province, Eastern China.

BACKGROUND: COVID-19 has spread worldwide and become a pandemic. We report the epidemiological and clinical characteristics of cluster infections. METHODS: Data of clustered cases were retrieved from the public health emergency monitoring information system of China. We analyzed the incubation period, generation gap, secondary attack rate, and viral load in various grouped cases. RESULTS: A total of 60 COVID-19 infection clusters including 226 patients and 19 asymptomatic cases involving four generations were analyzed. With the increase of transmission generations, secondary attack rate decreased (P＜0.001) and severity alleviated (P = 0.008). The median incubation period and intergenerational interval were 9 and 6 days, respectively. The secondary attack rate was 7.1% in the index cases, 5.0% in the first generation, 1.0% in the second generation, and 4.7% overall. Severe cases were seen more in the index (13, 65%) and first generation (7, 35%) ones, who had a significantly higher viral load than the mild and moderate ones. CONCLUSIONS: With the increase of transmission generation, secondary infection rate and severity decreased. Severe patients had a higher virus load. Patients in the incubation period and asymptomatic carriers were potential infection sources who might play an important role in transmission.

Epidemiologic characteristics and influencing factors of cluster infection of COVID-19 in Jiangsu Province.

To understand the characteristics and influencing factors related to cluster infections in Jiangsu Province, China, we investigated case reports to explore transmission dynamics and influencing factors of scales of cluster infection. The effectiveness of interventions was assessed by changes in the time-dependent reproductive number (Rt). From 25th January to 29th February, Jiangsu Province reported a total of 134 clusters involving 617 cases. Household clusters accounted for 79.85% of the total. The time interval from onset to report of index cases was 8 days, which was longer than that of secondary cases (4 days) (χ2 = 22.763, P < 0.001) and had a relationship with the number of secondary cases (the correlation coefficient (r) = 0.193, P = 0.040). The average interval from onset to report was different between family cluster cases (4 days) and community cluster cases (7 days) (χ2 = 28.072, P < 0.001). The average time interval from onset to isolation of patients with secondary infection (5 days) was longer than that of patients without secondary infection (3 days) (F = 9.761, P = 0.002). Asymptomatic patients and non-familial clusters had impacts on the size of the clusters. The average reduction in the Rt value in family clusters (26.00%, 0.26 ± 0.22) was lower than that in other clusters (37.00%, 0.37 ± 0.26) (F = 4.400, P = 0.039). Early detection of asymptomatic patients and early reports of non-family clusters can effectively weaken cluster infections.

Cluster infections play important roles in the rapid evolution of COVID-19 transmission: A systematic review.

OBJECTIVES: To summarise the major types of SARS-CoV-2 cluster infections worldwide through a comprehensive systematic review. METHODS: All studies published between 01 January-15 June 2020 on COVID-19 cluster infections in English electronic databases were searched, including PubMed, Embase, Web of Knowledge, and Scopus. All included studies were independently screened and evaluated by two authors, and information from each study was extracted using a standard form. RESULTS: Sixty-five studies were included, which involved 108 cluster infections from 13 countries, areas or territories. Seventy-two (66.7%) of the cluster infections were reported in China. The major types of cluster infections were families, community transmission, nosocomial infection, gatherings, transportation, shopping malls, conferences, tourists, religious organisations, workers, prisons, offices, and nursing homes. CONCLUSIONS: The SARS-CoV-2 can be transmitted in various circumstances, and cluster infections play an important role in the rapid evolution of COVID-19 transmission. Prevention and control measures such as social distancing must be strictly implemented to contain these cluster infections.