Changes in Incidence and Epidemiological Characteristics of Pulmonary Tuberculosis in Mainland China, 2005-2016

Abstract

Importance: The World Health Organization End TB (Tuberculosis) Strategy aims to decrease the global incidence and mortality of TB by 90% and 95%, respectively, as of 2035.

Objective: To characterize the recent epidemiological trend of pulmonary TB (PTB) in mainland China based on the national surveillance data.

Design, setting, and participants: This cross-sectional study collected demographic and clinical data of all patients reported in the national Tuberculosis Information Management System of China from January 1, 2005, to November 21, 2016. Data were analyzed from December 1, 2019, to July 31, 2020.

Exposures: Pulmonary TB was defined as bacteriologically confirmed or clinically diagnosed TB in the lung parenchyma or the tracheobronchial tree.

Main outcomes and measures: Temporal and spatial variation of annual incidence and demographic features of PTB in mainland China.

Results: In total, 10 582 903 patients with PTB were reported in mainland China from 2005 to 2016. The median age of patients with PTB was 46 (interquartile range [IQR], 30-61) years, and 28.53% were 60 years or older. Most patients with PTB were male (69.8%) and farmers or herders (70.0%). The mean (SD) incidence of PTB was 66.61 (8.09) per 100 000 population. The annual incidence decreased from 72.95 per 100 000 population in 2005 to 52.18 per 100 000 population in 2016, and the reduction was greater in the eastern and central regions (31.6%; from 69.43 to 47.48 per 100 000 population) than in the western region (21.0%; from 82.06 to 64.82 per 100 000 population). Xinjiang Uygur Autonomous Region (135.03 per 100 000 population), Guizhou Province (115.98 per 100 000 population), and the Tibet Autonomous Region (101.98 per 100 000 population) had the highest mean annual incidences. The median time from onset of illness to diagnosis decreased from 36 (IQR, 16-92) days from 2005 to 2007 to 31 (IQR, 15-63) days in 2008 and later (P < .001) and was longer in the western region than in the eastern and central regions (41 [IQR, 20-91] vs 30 [IQR, 13-61] days; P < .001).

Conclusions and relevance: Although this study found that the incidence of PTB in mainland China showed a downward trend from 2005 to 2016, to achieve the World Health Organization 2035 goal, innovative and more efficient prevention and control strategies are needed, particularly among the most susceptible population, that is, farmers and herders in western China.

Figure 1.. Temporal Pattern and Trends of Pulmonary Tuberculosis (PTB) in Mainland China, January 2005 to November 2016

A, Epidemic curve of PTB cases by year. B, Trends and joinpoints of PTB incidence. For the joinpoint model, PTB incidence = β₀ + β₁ (year) + β₂ (year + 2007) + E. C, Heat map of weekly proportion of PTB cases by province.

Figure 2.. Spatiotemporal Distribution of Patients With Pulmonary Tuberculosis (PTB) in Mainland China, January 2005 to November 2016

A, Annual and mean incidence of PTB per 100 000 population in the 31 Chinese provinces investigated. The 12 rings contain data for each year studied, starting from the innermost ring in 2005 to the outermost in 2016. B, Map of the mean annual incidence per 100 000 population of PTB by region before (2005-2007) the decrease in incidence based on the annual incidence per 100 000 population in mainland China. C, Map of the mean annual incidence of PTB by region after (2008-2016) the decrease in the incidence based on the annual incidence per 100 000 population in mainland China.

Figure 3.. Duration of Time From Illness Onset to Diagnosis of Pulmonary Tuberculosis (PTB) in Mainland China, January 2005 to November 2016

A, For all patients, median duration is 32 (interquartile range [IQR], 15-67) days. B, For patients before 2008, median duration is 36 (IQR, 16-92) days; patients in 2008 and later, 31 (IQR, 15-63) days. C, For patients in the eastern and central regions, median duration is 30 (IQR, 13-61) days; in the western region, 41 (IQR, 20-91) days. D, For male patients, median duration is 32 (IQR, 15-68) days; female, 33 (IQR, 15-69) days. E, For patients younger than 15 years, median duration is 31 (IQR, 14-62) days; aged 30 to 44 years, 32 (IQR, 15-68) days; aged 45 to 59 years, 33 (IQR, 16-70) days; and 60 years or older, 34 (IQR, 16-71) days. F, For patients among farmers and herders, median duration was 33 (IQR, 16-71) days; other occupations, 30 (IQR, 12-61) days.