Data archive
NIDRIS monitors 41 NIDs, categorized by China CDC into five groups by transmission routes: intestinal infectious diseases, respiratory infectious diseases, natural focal and vector-borne diseases, sexually transmitted and blood-borne infections, and diseases with other transmission routes [9]. Among these, diseases with other transmission routes includes multiple neglected tropical diseases, which have been analysed in previous studies [10]. Specifically, this study focuses on three major categories (intestinal infectious diseases, respiratory infectious diseases, and sexually transmitted and blood-borne infections), encompassing 21 diseases. Diseases lacking data in the GBD 2021 database (e.g., poliomyelitis, dysentery, scarlet fever) or with incomplete data in the NIDRIS (e.g., influenza A (H1N1) and hepatitis D) were excluded from the analysis. Additionally, due to the extremely low incidence of cholera and the absence of reported cases of severe acute respiratory syndrome (SARS) in recent years, along with the absence of data for both in the GBD 2021 database, they were excluded. Ultimately, this study included data from 14 NIDs reported between 2010 and 2020 across 31 provincial-level administrative divisions in China (not included Taiwan, Hong Kong, and Macau), comprising 4 intestinal infectious diseases (hepatitis A, hepatitis E, paratyphoid fever, typhoid fever), 5 respiratory infectious diseases [diphtheria, measles, meningitis, pertussis, tuberculosis (TB)], and 5 sexually transmitted and blood-borne infections [gonorrhoea, hepatitis B, hepatitis C, human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), syphilis].
As a globally recognized disease classification and diagnostic standard, the International Classification of Diseases (ICD) codes are used to systematically classify, identify, and record diseases, health conditions, injuries, and causes of death worldwide [11]. The GBD 2021 study mapped ICD codes, for both ICD-9 (1975) [12] and ICD-10 (1994) [13], to the GBD 2021 causes of death and nonfatal causes [14]. Additionally, the coding systems adopted by the China CDC from 2010 to 2020 (GB/T 14396–2001 [15] and GB/T 14396–2016 [16]) align with the ICD-10 standard of the World Health Organization (WHO). Therefore, we reviewed the coding for 14 NIDs across the coding standards published by China and ICD-10 to ensure consistency and comparability. The list of ICD codes mapped to 14 NIDs in the GBD 2021, along with the Classification and Codes of Diseases mapped to the 14 diseases in China, is provided in supplementary table S1.
Data on incident cases and deaths (by age and region) for 14 NIDs (2010–2020) were obtained from the Data-center of China Public Health Science (https://www.phsciencedata.cn/Share/index.jsp). Life expectancy in China during the same period were sourced from the China Statistical Yearbook [17]. Disease durations were determined through expert consultation and literature (see supplementary table S2). Disability weights (DWs) were based on related literature and the Global Health Data Exchange (https://ghdx.healthdata.org/record/ihme-data/gbd-2019-disability-weights), which is an online platform that publishes GBD results. Based on the DWs estimated from the GBD, this study recalculated the DWs according to the proportion of various symptoms of the 14 diseases in China (S2 Table). Estimated DALYs for the 14 NIDs in the same period were extracted from the GBD 2021 database (https://vizhub.healthdata.org/gbd-results/) for comparative analysis.
Data analysis
DALY calculation
To ensure consistency with the methodologies employed in the GBD study, this research utilizes a simplified DALY formula provided by the WHO [18, 19], to calculate the disease burden of NIDs in China (2010–2020). The number of incident cases and deaths were collected to calculate years of life lost (YLLs) and years lived with disability (YLDs), which were then summed to obtain DALYs. The formula is as follows:
$$YLL, = ,N times L;$$
(1)
$$YLD, = ,I times d times DW;$$
(2)
$$DALY, = ,YLL + YLD;$$
(3)
where N represents the number of deaths; and L is standard life expectancy at age of death in China (in years); I is the number of incident cases; d is the average duration of disease (in years); DW is the disability weight. DALYs for hepatitis A, hepatitis E, paratyphoid fever, typhoid fever, diphtheria, measles, meningitis, pertussis, TB, gonorrhoea, hepatitis B, and hepatitis C are calculated directly using the above formula. For HIV/AIDS and syphilis, the DALY values for each disease stage are calculated separately, and then summed to obtain the total DALYs for each disease. Except for the DW for pertussis, which is referenced from GBD 2019, the DWs for the remaining 13 diseases are sourced from GBD 2021.
The 95% uncertainty intervals for the DALYs associated with each disease were estimated using the Monte Carlo Simulation method, with 10,000 iterations [20]. In the simulation process, triangular distributions were applied to the relevant parameters to account for the inherent uncertainty in the data.
Visualization of DALY trends
DALYs for 14 NIDs in China (2010–2020) were calculated based on reported data and visualized using various graphical methods. Line charts were used to illustrate temporal changes in the overall disease burden, while bubble charts highlighted the relative contributions of each disease within the three major categories. Pie charts were employed to depict the proportional burden of each disease category, and a heatmap was created to illustrate the annual trends for each disease over the 11 year period.
Disease burden ranking
The 14 NIDs were ranked based on their 11 year average DALYs calculated from national surveillance data to identify the diseases contributing most significantly to the overall burden. These rankings were then compared with those derived from the GBD 2021 estimates to highlight potential discrepancies in disease prioritization between national surveillance data and modeled estimates.
Comparison of national surveillance data and GBD 2021 estimates
Discrepancies between the national surveillance data and GBD 2021 estimates were quantified by calculating the ratios of the 11-year average DALYs from the two sources.
Prevention and control policies for NIDs in China
Relevant prevention and control policies, guidelines, and achievements for NIDs in China were identified through searches using keywords such as “notifiable infectious diseases,” “immunize,” “prevention and control,” “diagnostic criteria,” “surveillance,” “expert consensus,” and “eliminate.” The search covered official websites of various governmental departments, including the China CDC, the National Health Commission of the People’s Republic of China (http://www.nhc.gov.cn/), the National Development and Reform Commission (https://www.ndrc.gov.cn/), and the State Council Policy Document Library (https://www.gov.cn/zhengce/zhengcewenjianku/index.htm). These platforms provided officially published policies, guidelines, and documents related to infectious disease control (in Chinese). Additionally, milestone achievements in infectious disease control were retrieved from CNKI and WHO-certified reports. Based on this information, a comprehensive historical timeline map was constructed, integrating key policies, guidelines, and certified disease elimination events.
Data extraction and integration were executed using Microsoft Excel 2021 (Microsoft, Redmond, USA), with all analyzes and visualizations conducted using R version 4.4.0 (Lucent Technologies, Jasmine Mountain, USA).