Epidemiological and clinical characteristics of COVID-19 patients in Nanjing (preprint)

Background: Since December 2019, the outbreak of COVID-19 has spread quickly and thumped many countries and regions. The epidemic of central China was under the spotlight and attracted much more attentions. However, there are few reports describing COVID-19 patients in the regions outside of Wuhan, which are undergoing the change from sporadic imported cases to community-acquired transmission.Methods: The electronic medical records of 74 laboratory-confirmed patients of COVID-19 were retrospectively reviewed and analyzed. Their epidemiological, demographic, clinical and radiological characteristics were systematically summarized. The difference between severe patients and non-severe patients were also analyzed statistically.Results: The 74 COVID-19 patients were composed of 4 (5.4%) mild patients, 56 (75.7%) common patients, 13 (17.6%) severe patients and 1 (1.4%) critical patient. 43 were male, and 31 were female, with the average age 48.1±17.5. No significant difference of susceptibility was observed between genders, and almost people with all age were susceptible to SARS-CoV-2 infection. Before Jan 26, only imported sporadic cases were observed. However, from that day onward, family cluster infection cases increased dramatically, up to 70.3% (52/74), which were mainly from 15 family. The incubation period spanned from 0 to 19 days, with the median 5, and 81.4% had symptom onset within 7 days. At admission, 31.1% of patients had underlying diseases and the most common underlying diseases were hypertension (13.5%) and diabetes (5.4%). The most common symptoms were fever (90.5%), cough (75.7%), fatigue (36.5%) and chest distress (32.4%). 36.5% and 16.2% of patients had leukopenia and lymphocytopenia. 43.2% of patients had increased C reactive protein (CRP), and 40.5% had higher erythrocyte sedimentation rate (ESR) and 21.6% had higher calcitonin. 74.3% of patients had obvious lesions in both lung lobes and 56.8% of lesions manifested as ground glass opacity. Compared with non-severe group, the severe/critical group were significantly older and had more underlying diseases. After treatment, all patients improved and were discharged. No medical professional infection and death case were reported.Conclusion: The epidemic of COVID-19 in Nanjing were mainly caused by family cluster infection. The entire prevalence and illness were much milder than those of Wuhan. The disease of COVID-19 could be controlled and cured.  

Early and critical care in severe patients with COVID-19 infection in Jiangsu Province, China: a descriptive study (preprint)

Background: Patients with coronavirus disease 2019 (COVID-19) infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which originated in Wuhan, China, and spreading over the country including Jiangsu Province. Our study aimed to study the epidemiological, clinical characteristics and therapies of these severe cases in Jiangsu Province.Methods: A multicenter retrospective cohort study was conducted to extract and analyze epidemiological, clinical, laboratory data and treatment of 60 severe cases with COVID-19 infection from 12 large hospitals in Jiangsu Province between Jan 24 and Feb 23, 2020. Cases were identified by real-time reverse transcription polymerase chain reaction (RT-PCR). The improvement and deterioration subgroups were compared to identify predictors of disease progression. Clinical outcomes were followed up until Feb 23, 2020.Results: A total of 631 infected cases with COVID-19 in Jiangsu Province, 60 of which were severe cases. Up until Feb 23, 2020, the mortality rate of these severe patients was 0%. The median age was 57 years (range, 26 to 97), and 58.3% were man. The body mass index (BMI) of these patients was higher, with an average of 25 kg/m². More than 90 percent of the patients had a history of contact with an infected patient or dined together, and two patients were infected while staying in the same train compartment with a confirmed patient. 51.7% of severe cases had at least one underlying disease, and low fever (80.0%) and dry cough (51.7%) were the most common symptoms. Mean acute physiology and chronic health evaluation (APACHE) II score on admission was 14±5. Acute respiratory distress syndrome (ARDS) appeared in 15% of the patients. White blood cell counts decreased in 45.0% of patients, lymphopenia in 63.3%, thrombocytopenia in 13.3%, and procalcitonin levels in 88.3% of the patients were less than 0.5 ng/mL. There were no statistically significant differences in immunoglobulin therapy and glucocorticoids therapy between the improvement and deterioration subgroups (P>0.05). Logistic regression analysis indentified higher levels of troponin T (odds ratio [OR]: 1.04; 95% confidence interval [CI]: 1.00-1.08; P=0.04), antiviral therapy with interferon (OR: 6.33; 95% CI: 1.18-33.98; P=0.03), and the application of non-invasive mechanical ventilation (OR: 1.99; 95%CI: 1.17-3.41; P=0.01) as predictors of disease progression, whereas higher lymphocyte count (OR: 0.11; 95% CI: 0.02-0.57; P=0.01) and early prone ventilation were associated with improvement (OR: 0.11; 95% CI: 0.01-0.98; P=0.04).Conclusions: The COVID-19 infection had a low mortality rate in Jiangsu Province, China. The higher levels of troponin T and lower lymphocyte count were predictors of disease progression. Antiviral therapy with interferon was not recommended. The early prone ventilation may be an effective treatment for severe cases.

Comparative study of the lymphocyte change between COVID-19 and non-COVID-19 pneumonia cases suggesting uncontrolled inflammation might not be the main reason of tissue injury (preprint)

Background: The corona virus disease 2019 (COVID-19) shows unusually high transmission rate and unique clinical characteristics, with key pathological mechanism remaining unclear. Here, we analysed the laboratory data based on clinical samples from COVID-19 patients, in parallel comparison with non-COVID-19 pneumonia cases, in an attempt to elucidate the key pathological features of COVID-19 during its infection of the human body. Methods: We analysed biochemical indices and lymphocyte subpopulation in COVID-19 patients, and compare these data from non-COVID-19 pneumonia cases. Correlation analysis was performed between leukocyte subgroups count and biochemical indexes in COVID-19 patients. Results: The study enrolled 110 patients, comprising 88 COVID-19 patients and 22 non-COVID-19 pneumonia cases. We observed significant differences, including abnormal biochemical indices (CRP, LDH, AST, eGFR, and sodium ion concentration) and reduced lymphocyte subsets count, between the COVID-19 patients and non-COVID-19-caused pneumonia cases. Correlation analysis indicates that the count for lymphocyte subsets-but not that for neutrophils and monocytes-exhibits a significant negative correlation with biochemical indices relating to organ injury, in the COVID-19 infected patients. Conclusions: The study indicates significantly different clinical features between 2019 novel coronavirus (2019-nCoV)-caused and non-2019-nCoV-caused pneumonia, especially in terms of lymphocytopenia and organ injury. Notably, correlation analysis demonstrates that tissue damage in COVID-19 patients is attributed to virus infection itself rather than uncontrolled inflammatory responses ("cytokine storm"). These findings provide new insights for developing efficient therapeutic strategies against COVID-19 infection.

Clinical Characteristics of 24 Asymptomatic Infections with COVID-19 Screened among Close Contacts in Nanjing, China (preprint)

Background: Previous studies have showed clinical characteristics of patients with the 2019 novel coronavirus disease (COVID-19) and the evidence of person-to-person transmission. Limited data are available for asymptomatic infections. This study aims to present the clinical characteristics of 24 cases with asymptomatic infection screened from close contacts and to show the transmission potential of asymptomatic COVID-19 virus carriers. Methods: Epidemiological investigations were conducted among all close contacts of COVID-19 patients (or suspected patients) in Nanjing, Jiangsu Province, China, from Jan 28 to Feb 9, 2020, both in clinic and in community. Asymptomatic carriers were laboratory-confirmed positive for the COVID-19 virus by testing the nucleic acid of the pharyngeal swab samples. Their clinical records, laboratory assessments, and chest CT scans were reviewed. Findings: None of the 24 asymptomatic cases presented any obvious symptoms before nucleic acid screening. Five cases (20.8%) developed symptoms (fever, cough, fatigue and etc.) during hospitalization. Twelve (50.0%) cases showed typical CT images of ground-glass chest and five (20.8%) presented stripe shadowing in the lungs. The remaining seven (29.2%) cases showed normal CT image and had no symptoms during hospitalization. These seven cases were younger (median age: 14.0 years; P = 0.012) than the rest. None of the 24 cases developed severe COVID-19 pneumonia or died. The median communicable period, defined as the interval from the first day of positive nucleic acid tests to the first day of continuous negative tests, was 9.5 days (up to 21 days among the 24 asymptomatic cases). Through epidemiological investigation, we observed a typical asymptomatic transmission to the cohabiting family members, which even caused severe COVID-19 pneumonia. Interpretation: The asymptomatic carriers identified from close contacts were prone to be mildly ill during hospitalization. However, the communicable period could be up to three weeks and the communicated patients could develop severe illness. These results highlighted the importance of close contact tracing and longitudinally surveillance via virus nucleic acid tests. Further isolation recommendation and continuous nucleic acid tests may also be recommended to the patients discharged.