Objective:To analyze the epidemic characteristics of brucellosis in China from 2004 to 2018, in order to understand the development trend of brucellosis.Methods:The surveillance data of brucellosis in China from 2004 to 2018 were collected from National Public Health Science Data Center. Joinpoint regression was used to analyze the trend of brucellosis incidence in China and various provinces. Overall trends were estimated by the average annual percentage change (AAPC). Seasonal and trend decomposition using loess (STL) was used to analyze the seasonal characteristics of brucellosis in China and various provinces. The age-related thermodynamic diagram of incidence rate was used to analyze the characteristics of age-onset changes.Results:From 2004 to 2018, a total of 524 980 brucellosis cases and 16 deaths were reported nationwide, with a incidence rate of 2.61/100 000 and a case fatality rate of (3.05 × 10 -3)%. The incidence of brucellosis in China was on the rise (AAPC = 11.58%, 95% CI: 7.91% - 15.25%, P < 0.001). There was no significant trend of change in Inner Mongolia Autonomous Region, Shanxi and Shaanxi provinces ( P > 0.05). Tibet Autonomous Region showed a downward trend (AAPC = - 55.19%, P < 0.001). All other provinces were showing an upward trend (AAPC > 0, P < 0.05). The peak incidence in China occurred from April to June. In terms of provinces, the peak incidence in Hainan, Sichuan, Guizhou, Fujian and Anhui provinces occurred from April to August, the peak incidence in Chongqing and Shanghai cities occurred from June to August, and the peak incidence in other provinces was generally from April to June. There were reports of brucellosis cases in all age groups nationwide, and the age distribution showed an inverted "V" shape. The peak incidence occurred in the 50 - 54 years old (5.43/100 000), followed by the 60 - 64 years old (4.94/100 000). From 2004 to 2018, the top 3 age groups of incidence rate changed from 40 - 44, 50 - 54 and 35 - 39 years old in 2004 to 50 - 54, 60 - 64 and 55 - 59 years old in 2018. Conclusions:The incidence of brucellosis is on the rise nationwide and in most provinces from 2004 to 2018. The high incidence age is gradually changing to the elderly population.

Objective:To learn about the age, period, birth cohort characteristics, and incidence trends of hemorrhagic fever with renal syndrome (HFRS) nationwide.Methods:HFRS monitoring data from 2004 to 2018 were collected from the National Public Health Science Data Center (https://www.phsciencedata.cn/). The trend of incidence rate of HFRS was analyzed by joinpoint regression, and the linear trend was estimated by annual percentage change (APC) and average annual percentage change (AAPC). Bayesian Age-Period-Cohort (BAPC) analysis of the effects of age, period, and birth cohort on HFRS cases was conducted, with age, period, and birth cohort used as reference for the 40 - 44 age group, 2011, and 1968, respectively, the RR and 95% CI were calculated. Results:From 2004 to 2018, a total of 190 197 HFRS cases were reported nationwide, with an average annual incidence rate of 0.95/100 000. Among them, the highest incidence rate of HFRS was 1.93/100 000 in 2004. Since 2007, it had continued to fluctuate below 1.00/100 000, ranging from 0.66/100 000 to 0.99/100 000. Joinpoint regression fitting results showed that the overall incidence of HFRS in China was declining (AAPC = - 7.33%, 95% CI: - 8.07% - - 6.58%, P < 0.001); the APCs from 2004 to 2007, 2007 to 2009, and 2012 to 2016 were - 32.00%, - 8.74%, and - 9.02%, respectively, all showed a downward trend( P < 0.05); the APCs from 2009 to 2012 and from 2016 to 2018 were 14.69% and 11.38%, respectively, both showed an upward trend ( P < 0.05). HFRS cases were reported in all age groups, and the reported incidence rate showed a unimodal distribution with age. Among them, the highest incidence rate was in the 50 - 54 age group (1.75/100 000), and the lowest incidence rate was in the 0 - 4 age group (0.03/100 000); the proportion of cases in the age group of 60 years and above increased from 9.75% in 2004 to 25.90% in 2018, showed an increasing trend year by year (χ 2trend = 9 210.90, P<0.001). The analysis results of the BAPC model showed that in the age effect analysis, compared with the reference age group, there was no significant difference in the incidence risk among the age groups of 15 - 79 years old ( P > 0.05), while the incidence risk was lower in the age groups of 14 years old and below, and 80 years old and above ( RR < 1, P < 0.05). In the analysis of period effects, compared with the reference year, the incidence risk was higher from 2004 to 2006 and from 2012 to 2014 ( RR > 1 , P < 0.05), and lower from 2008 to 2010 and from 2017 to 2018 ( RR < 1, P < 0.05); the overall trend was consistent with the descriptive analysis of onset period. In the analysis of birth cohort effect, compared with the reference cohort, the population born between 1920 - 1935 and 1970 - 2018 had lower incidence risk ( RR < 1, P < 0.05); but the risk of disease in the population born after 2003 showed an upward trend. Conclusions:The HFRS epidemic in China has decreased from 2004 to 2018, but the downward trend in recent years is not significant. The incidence risk has increased among people born after 2003. The population aged 60 and above is a key group for further controlling the HFRS epidemic in China.

Objective To explore the applicability of the TBATS in predicting the incidence of mumps. Methods The incidence of mumps of Jiangxi Province from 2004 to 2017 was used as the demonstration data. The incidence of mumps in Jiangxi Province from July to December 2017 was used as test data. The training data from January 2004 to June 2017 were used to train the TBATS and the SARIMA, and predict the value from July to December 2017. The fitted and predicted values were compared with the test data. The MAPE, RMSE, MAE and MER were used to evaluate model fitting and prediction effects. Results SARIMA (1,0,0)(1,1,0)₁₂ with drift was the optimal SARIMA. The MAPE, MAE, RMSE and MER fitted by the TBATS and the SARIMA were 15.06%, 0.21, 0.29, 13.57% and 21.93%, 0.29, 0.41, 18.73%, respectively. The MAPE, MAE, RMSE and MER predicted by the TBATS and the SARIMA were 7.95%, 0.08, 0.11, 7.12% and 15.33%, 0.17, 0.18, 14.93%. Conclusion The TBATS has high accuracy in predicting the incidence of mumps and is worthy of popularization and application.