Epidemiological investigation and intergenerational clinical characteristics of 24 COVID-19 patients associated with supermarket cluster

Abstract

Objective: To analyze the epidemiological and intergenerational clinical characteristics of COVID-19 patients associated with cluster, so as to understand the rules of the patients associated with cluster of this outbreak and provide help for the prevention and control of COVID-19. Methods: All close contacts of the patient were screened since the first supermarket employee with COVID-19 was identified. A retrospective analysis was made on the epidemiological and clinical characteristics of the confirmed cases admitted to the designated hospitals for centralized treatment. The patients were divided into two groups according to the first generation (supermarket employees, group A) and the second or third generation (family members or friends of supermarket employees, group B), and the similarities and differences between the two groups were compared. Results: A total of 24 COVID-19 patients were diagnosed, with an average age of 48±1.73 years. The mean duration from onset to release form quarantine was 21.04±6.77 days, and the onset time was concentrated in 5-11 days after the first patient was diagnosed. Among all the patients, 23 patients were moderate, among which 7 patients (29.17%) were asymptomatic. Symptoms of symptomatic patients were cough (75.00%), low fever (62.50%), shortness of breath (41.67%), sore throat (25.00%), gastrointestinal symptoms (25.00%), fatigue (20.83%), etc. Biochemical examination on admission showed that the white blood cell count < 4.010×9/L (29.17%) and the lymphocyte count <1.1×109/L (58.33%). The lymphocyte count of 50.00% of the patients was ≤0.6×109/L. On admission, chest CT showed pneumonia (100%) with bilateral infiltration (75.00%). Treatment: antiviral drug (100%), Chinese medicine (100%), common oxygen therapy (45.83%). There were 11 cases in group A (first generation, 11 cases) and 13 cases in group B (second generation, 11 cases; third generation, 2 cases). In group B, there were more males, from onset to admission later, more patients had underlying diseases, and more patients were treated with albumin (P<0.05). However, there was no statistical difference between the two groups in other clinical indicators, including the duration from onset to release form quarantine(P>0.05). There was no improvement in granulocyte count in all patients, as well as in groups A and B, between admission and release from quarantine(P>0.05). Conclusion: The clinical characteristics of COVID-19 patients associated with cluster were similar to those of other COVID-19 patients, but there were some special features. The severity of the disease was similar and there was intergenerational spread. There was no difference in clinical characteristics between generations. Asymptomatic infections occurred in a proportion of patients and could cause spread.

Estimating the extent of asymptomatic COVID-19 and its potential for community transmission: Systematic review and meta-analysis

“…Diagnosis in all studies was confirmed via RT-PCR and in two cases supplemented with radiological evidence (17,21). Testing of individuals within the study sample varied across settings but was generally very high: all contacts regardless of symptoms (11,13,14,17,18,21); >97% of SNF residents (10,12,15,19,20) and 85.9% of an entire town (16). Length of This article has undergone peer review and been accepted for publication by JAMMI.…”

“…Thirteen articles, nine published and four preprints, from seven countries (China (4), United States of America (USA) (4), Taiwan (1), Brunei (1), Korea (1), France (1) and Italy (1)) that tested 21,708 close contacts of at least 849 confirmed COVID-19 cases, of which 663 were positive and 111 were asymptomatic, met eligibility criteria for the estimation of the primary outcome (10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22). Their sampling frames included residents of skilled nursing facilities (SNF) (10,12,15,19,20); high-risk close contacts of confirmed COVID-19 cases (11,13,14,17,18,21); and a whole district surveillance program in Italy (16). The demographic characteristics (Table 1) indicate that most of the tested individuals were adults, with mean age over 75 years in the five SNF studies and mean over 31 years in the non-aged care studies.…”

Asymptomatic SARS-CoV-2 infections: a living systematic review and meta-analysis

“…We included four studies that reported on outbreak investigations arising from a single symptomatic person with covid-19 in a chalet in France, 21 a flight from Singapore carrying passengers returning to China, 40 a nursing home in the United States of America, 23 and a supermarket employee in China. 35 The summary estimate of the proportion of asymptomatic SARS-CoV-2 infections was 16% (95% CI 7 to 34%).…”

Occurrence and transmission potential of asymptomatic and presymptomatic SARS-CoV-2 infections: A living systematic review and meta-analysis

“…In nine studies that reported on close contacts of infected individuals and aggregated data from clusters of both asymptomatic and symptomatic people with SARS-CoV-2 the summary estimate was 14% (95% CI 8%-23%, prediction interval 2%-53%) [36,47,60,62,66,72,105,108,111]. We included 12 studies (n = 675 people) that reported on outbreak investigations arising from a single symptomatic person or from the country's first imported cases of people with COVID-19 [32,43,48,58,61,68,71,90,94,95,97,100]. Four of the outbreaks involved nursing homes [58,68,71,94] and four involved occupational settings [43,61,90,95].…”

“…We included 12 studies (n = 675 people) that reported on outbreak investigations arising from a single symptomatic person or from the country's first imported cases of people with COVID-19 [32,43,48,58,61,68,71,90,94,95,97,100]. Four of the outbreaks involved nursing homes [58,68,71,94] and four involved occupational settings [43,61,90,95]. The summary estimate of…”