This study retrospectively analyzed the spatio-temporal distribution and spatial clustering of scarlet fever in mainland China from 2004 to 2017. In recent years, the incidence of scarlet fever is increasing. Previous studies on the spatial distribution of scarlet fever in China are mainly focused at the provincial and municipal levels, and there is few systematic report on the spatial and temporal distribution characteristics of scarlet fever on the national level. Based on the incidence information of scarlet fever in mainland China between 2004 and 2017 collected from the China Center for Disease Control, this paper systematically explored the Spatio-temporal distribution of scarlet fever by three methods, contains spatial autocorrelation analysis, Spatio-temporal scanning analysis, and trend surface analysis. The results demonstrate that the incidence of scarlet fever varies by seasons, which is in line with double-peak distribution.The first peak generally occurs from May to June and the second one from November to December, while February and August is the lowest period of incidence. Trend surface analysis indicates that the incidence of scarlet fever in northern China is higher than the south, slightly higher in western compared to the east, and lower in the central part. Additionally, the results show that the clustering regions of scarlet fever centrally distributed in the northeast, northwest, north china and some provinces in the east, such as Zhejiang, Shanghai, Shandong, and Jiangsu.

23 Background: A new human coronavirus named SARS-CoV-2 emerged during 24 December 2019 in Wuhan, China. Cases have been exported to other Chinese cities and 25 abroad, which may cause the global outbreak. Chang Sha is the nearest provincial 26 capital city to Wuhan, the first case of COVID-19 in Changsha was diagnosed on 27 January 21, 2020. Estimating the transmissibility and forecasting the trend of the 28 outbreak of SARS-CoV-2 under the prevention and control measures in Changsha could 29 inform evidence based decisions to policy makers.30 Methods : Data were collected from the Health Commission of Changsha and Hunan 31 Center for Disease Control and Prevention. A Susceptible-exposed-infections/ 32 asymptomatic-removed (SEIAR) model was established to simulate the transmission of 33 SARS-CoV-2 in Changsha. Berkeley Madonna 8.3.18 were employed for the model 34 simulation and prediction, while the curve fitting problem was solved by the 35Runge-Kutta fourth-order method, with a tolerance of 0.001. 36Results: In this study, we found that Rt was 2.05 from January 21 to 27 and reduced to 37 0.2 after January 27, 2020 in Changsha. The prediction results showed that when no 38 obvious prevention and control measures were applied, the total number of patients in 39 Changsha would reach the maximum (2.27 million) on the 79th day after the outbreak, 40 and end in about 240 days; When measures have not been fully launched, the total 41 number of patients would reach the maximum (1.60 million) on the 28th day after the 42 outbreak, and end in about 110 days; When measures have been fully launched, the total 43 number of patients would reach the maximum (234) on the 23rd day after the outbreak, 44 3 and end in about 60 days. 45 Conclusions: Outbreak of SARS-CoV-2 in Changsha is in a controllable stage under 46 current prevention and control measures, it is predicted that the cumulative patients 47 would reach the maximum of 234 on February 12, and the outbreak would be over on 20 48 March in Changsha. With the fully implementation of prevention and control measures, 49 it could effectively reduce the peak value, short the time to peak and duration of the 50 outbreak.51 52

Objective To investigate the epidemiological characteristics, clinical features, treatment and short-term prognosis of SARS-CoV-2 infection in children.Methods A retrospective analysis was conducted in children with SARS-CoV-2 admitted to twelve hospitals in eight cities in Hunan province, China, from January 26, 2020 to June 30, 2020.Results A total of 48 children were enrolled in this study. 11 cases (23%) were asymptomatic, 15 cases (31%) were mild, 20 cases (42%) were moderate, and 2 cases (4%) were severe. No children were critical requiring intensive care. The most common symptom was fever (42%), cough (40%), fatigue (17%) and diarrhea (10%). The total peripheral blood leukocytes count decreased in two case (4%), Lymphocytopenia was present in 5 cases (10%). There were abnormal chest CT changes in 22 children (46%), including 15 (68%) with patchy ground glass opacity. In addition to supportive treatment, 41 children (85%) received antiviral therapy, 11 patients and (23%) were treated with antibiotics, 2 children (4%) were treated with methylprednisolone and IVIG. There was no death occurred.Conclusions Most children with SARS CoV-2 infection in Hunan province were asymptomatic, mild or moderate. Severe cases are rare. Close family contact was the main route of infection. The younger the age, the less obvious symptoms for children might be. Epidemiological history, nucleic acid test and chest imaging were important tools for the diagnosis in children.

Background: Influenza is a worldwide public health problem which causes a serious economic and health burden. In order to provide a scientific basis for improving the prevention and control level of influenza, using dynamic model to evaluate the infection rates of influenza different subtypes from 2010 to 2019 in China. Methods: This article established SEIABR model and calculated the infection rates of different influenza subtypes by using the Berkeley Madonna software. Results: The average infection rate of influenza was (7.95±1.27)×10-10 , and influenza A was (7.25±0.82) ×10-10, influenza B was (5.88±0.97)×10-10. In addition, the infection rates of A /H1N1, A/H3N2, B/Yamagata and B/Victoria were (7.25±0.82) ×10-10, (6.13±0.35) ×10-10, (6.01±0.52) ×10-10, (6.37±0.79) ×10-10. Conclusion: Between each year, flu transmission capacity had fluctuation. Influenza A was more transmissible than influenza B, and during the major subtypes, influenza A/H1N1 was the most transmissible.

Background A new infectious disease, Coronavirus disease 2019 (COVID-19) has been first reported during December 2019 in Wuhan, China, cases have been exported to other cities and abroad rapidly. Hunan is the neighboring province of Wuhan, a series of preventive and control measures were taken to control the outbreak of COVID-19. It is critical to assess these measures on the epidemic progression for the benefit of global expectation.Method: A Susceptible-exposed-infections/asymptomatic-removed (SEIAR) model was established to evaluate the effect of preventive measures. Berkeley Madonna 8.3.18 was employed for the model simulation and prediction, and the curve-fitting problem was solved by Runge-Kutta fourth-order method.Results In this study, we found that Rt was 2.71 from January 21 to 27 and reduced to 0.21 after January 27, 2020. If measures have not been fully launched, patients in Hunan would reach the maximum (8.96 million) on March 25, 2020, and end in about 208 days; when measures have been fully launched, patients in Hunan would just reach the maximum (699) on February 9, 2020, and end in about 56 days, which was very closed to the actual situation.Conclusion The outbreak of COVID-19 in Hunan, China has been well controlled under current measures, full implementation of measures could reduce the peak value, short the time to peak and duration of the outbreak effectively, which could provide a reference for controlling of COVID-19 for other countries.