Real-time risk ranking of emerging epidemics based on optimized moving average prediction limit-taking the COVID-19 pandemic as an example.

BACKGROUND: Mathematical models to forecast the risk trend of the COVID-19 pandemic timely are of great significance to control the pandemic, but the requirement of manual operation and many parameters hinders their efficiency and value for application. This study aimed to establish a convenient and prompt one for monitoring emerging infectious diseases online and achieving risk assessment in real time. METHODS: The Optimized Moving Average Prediction Limit (Op-MAPL) algorithm model analysed real-time COVID-19 data online and was validated using the data of the Delta variant in India and the Omicron in the United States. Then, the model was utilized to determine the infection risk level of the Omicron in Shanghai and Beijing. RESULTS: The Op-MAPL model can predict the epidemic peak accurately. The daily risk ranking was stable and predictive, with an average accuracy of 87.85% within next 7 days. Early warning signals were issued for Shanghai and Beijing on February 28 and April 23, 2022, respectively. The two cities were rated as medium-high risk or above from March 27 to April 20 and from April 24 to May 5, indicating that the pandemic had entered a period of rapid increase. After April 21 and May 26, the risk level was downgraded to medium and became stable by the algorithm, indicating that the pandemic had been controlled well and mitigated gradually. CONCLUSIONS: The Op-MAPL relies on nothing but an indicator to assess the risk level of the COVID-19 pandemic with different data sources and granularities. This forward-looking method realizes real-time monitoring and early warning effectively to provide a valuable reference to prevent and control infectious diseases.

High positive rate after consecutive negative tests of SARS-CoV-2.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been a global public health event since 2019. Real-time reverse transcription polymerase chain reaction (RT-PCR) assays of upper respiratory tract specimens were used as the most common method for confirmation of SARS-CoV-2. Patients diagnosed with coronavirus disease 2019 and hospitalized in Cancer Center of Wuhan Union Hospital were retrospectively enrolled. Epidemiological, clinical, and laboratory records were analyzed with highlights on the pattern of results of repeated RT-PCR tests. Nine hundred eighty-four patients admitted to hospital between February 13, 2020 to March 10, 2020 were enrolled. The median age was 62.0 years (interquartile range 49.0-68.0) and 44.5% was male. Three thousand-three hundred eleven specimens were collected for RT-PCR tests with a median of 3 tests (interquartile range 2.0-4.0) per patient. Three hundred sixty-two (36.8%) patients showed positive records from repeated RT-PCR tests. For the 362 confirmed patients, 147 cases received further RT-PCR tests after 2 consecutive negative records of SARS-CoV-2 and 38 (26%) of them obtained a positive result. Ten (23%) of 43 patients showed positive results after 3 consecutive negative tests and 4 (24%) of 17 patients were positive after 4 negative tests. Consecutive negative RT-PCR tests with respiratory specimens could not guarantee a viral clearance.

Clinical Features of 69 Cases With Coronavirus Disease 2019 in Wuhan, China.

BACKGROUND: From December 2019 to February 2020, 2019 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a serious outbreak of coronavirus disease 2019 (COVID-19) in Wuhan, China. Related clinical features are needed. METHODS: We reviewed 69 patients who were hospitalized in Union hospital in Wuhan between 16 January and 29 January 2020. All patients were confirmed to be infected with SARS-CoV-2, and the final date of follow-up was 4 February 2020. RESULTS: The median age of 69 enrolled patients was 42.0 years (interquartile range 35.0-62.0), and 32 patients (46%) were men. The most common symptoms were fever (60 [87%]), cough (38 [55%]), and fatigue (29 [42%]). Most patients received antiviral therapy (66 [98.5%] of 67 patients) and antibiotic therapy (66 [98.5%] of 67 patients). As of 4 February 2020, 18 (26.9%) of 67 patients had been discharged, and 5 patients had died, with a mortality rate of 7.5%. According to the lowest SpO2 during admission, cases were divided into the SpO2 ≥ 90% group (n = 55) and the SpO2 < 90% group (n = 14). All 5 deaths occurred in the SpO2 < 90% group. Compared with SpO2 ≥ 90% group, patients of the SpO2 < 90% group were older and showed more comorbidities and higher plasma levels of interleukin (IL) 6, IL10, lactate dehydrogenase, and C reactive protein. Arbidol treatment showed tendency to improve the discharging rate and decrease the mortality rate. CONCLUSIONS: COVID-19 appears to show frequent fever, dry cough, and increase of inflammatory cytokines, and induced a mortality rate of 7.5%. Older patients or those with underlying comorbidities are at higher risk of death.

Calming the Cytokine Storm in Pneumonia by Biomimetic Nanoparticles.

Recently, the Wang group at Soochow University and the Gu group at the University of California, Los Angeles demonstrated the targeting ability of platelet-derived extracellular vesicles to deliver anti-inflammatory drug [5-(p-fluorophenyl)-2-ureido] thiophene-3-carboxamide (TPCA-1) to pneumonia for calming the local cytokine storm in acute lung injury.

Household transmission of SARS-CoV-2.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused an epidemic in China and many other countries. Many infected clusters have been found within familial households, but the data about secondary transmission among household contacts is limited. METHODS: In this retrospective case series, we enrolled 85 patients infected with SARS-CoV-2 and their household members in Wuhan. Patients were confirmed infected with SARS-CoV-2 by real-time reverse transcription polymerase chain reaction (RT-PCR) assays on throat swabs. Epidemiological, clinical and laboratory data of the household members were collected. RESULTS: There were 155 close contacts in total. 104 contacts received RT-PCR assays, with 47 (30%) positive cases and 57 (37%) negative cases. 51 (33%) cases did not received RT-PCR tests for they showed no symptoms of pneumonia during the 2 weeks of quarantine. The infection rate of close contacts was 38% for households with 1 contact, 50% for households with 2 contacts, and 31% for households with 3 contacts. CONCLUSIONS: The rate of secondary transmission among household contacts of patients with SARS-CoV-2 infection was 30%. Our data provide insight into the rate of secondary transmission of SARS-CoV-2 in home.