Coordinated multi-sectoral efforts needed to address the COVID-19 pandemic: lessons from China and the United States.

The COVID-19 pandemic has caused staggering human and economic costs. We outline four key lessons learned from efforts to address the pandemic in China and the US. First, effective surveillance, reporting, and contact tracing are needed to contain an epidemic at its emergence and to mitigate its impact at a later stage. Second, multi-sectoral efforts to offer incentives for those with no or minor symptoms to seek care and to quarantine themselves are critical, which would need concerted efforts from payers, providers, and public health. Third, sustained and routine prevention efforts involving both the public and the health systems will prove to be useful in times of a pandemic. Fourth, a strong public health system is essential and will be appreciated at times of urgency. Concerted multi-sectoral efforts are required to address COVID-19 pandemic with strong leadership from the public health sector.

Impact of Qingdao's smoke-free legislation on hospitalizations and mortality from acute myocardial infarction and stroke: an interrupted time-series analysis.

BACKGROUND AND AIMS: More than 20 cities in China have enacted local smoke-free laws that prohibit smoking in public places. Only two of these cities have examined the health impact of the law. Enacted in 2013, Qingdao's smoke free-law was stricter than most other municipal smoke-free laws because it did not allow designated smoking rooms. This study aimed to estimate the impact of Qingdao's smoke-free legislation on acute myocardial infarction (AMI) and stroke. DESIGN, SETTING AND PARTICIPANTS: We used an interrupted time-series design adjusting for underlying secular trends, seasonal patterns and meteorological factors to estimate the impact of the smoke-free law on AMI and stroke events among permanent residents aged 35 years or older in Qingdao, China. The study period was from 1 January 2010 to 31 December 2015, with a post-ban follow-up of approximately 2.5 years. MEASUREMENT: Outcome measures were weekly numbers of hospitalizations and deaths due to AMI/stroke. FINDINGS: A total of 10 371 and 56 101 patients were hospitalized, with a principal discharge diagnosis of AMI and stroke, respectively; 32 196 AMI and 49 711 stroke deaths occurred during the study period. Following the smoke-free legislation, an incremental 20% [95% confidence interval (CI) = 14-26%] and 8% (95% CI = 3-13%) decrease per year was observed in AMI and stroke hospitalization rates, respectively. Neither the immediate nor gradual change in AMI nor stroke mortality rates associated with the law was statistically significant (P > 0.05). Post-hoc subgroup analyses indicated that statistically significant reductions in AMI hospitalizations were evident among both the 35-64 (18% per year, 95% CI = 12-27%) and 65-84 (20% per year, 95% CI = 12-27%) age groups. Statistically significant reductions in stroke hospitalization were only in the older subgroup (13% per year, 95% CI = 8-18%). CONCLUSIONS: The 2013 smoke-free legislation in Qingdao, China was associated with reduction in hospitalization from acute myocardial infarction and stroke among permanent residents aged 35 years or older. There was no statistically significant reduction in mortality from acute myocardial infarctions or stroke.

Impact of smoke-free legislation on acute myocardial infarction and stroke mortality: Tianjin, China, 2007-2015.

BACKGROUND: Smoke-free legislation is an effective way to protect the population from the harms of secondhand smoke and has been implemented in many countries. On 31 May 2012, Tianjin became one of the few cities in China to implement smoke-free legislation. We investigated the impact of smoke-free legislation on mortality due to acute myocardial infarction (AMI) and stroke in Tianjin. METHODS: An interrupted time series design adjusting for underlying secular trends, seasonal patterns, population size changes and meteorological factors was conducted to analyse the impact of the smoke-free law on the weekly mortality due to AMI and stroke. The study period was from 1 January 2007 to 31 December 2015, with a 3.5-year postlegislation follow-up. RESULTS: Following the implementation of the smoke-free law, there was a decline in the annual trends of AMI and stroke mortality. An incremental 16% (rate ratio (RR): 0.84; 95% CI: 0.83 to 0.85) decrease per year in AMI mortality and a 2% (RR: 0.98; 95% CI: 0.97 to 0.99) annual decrease in stroke mortality among the population aged ≥35 years in Tianjin was observed. Immediate postlegislation reductions in mortality were not statistically significant. An estimated 10 000 (22%) AMI deaths were prevented within 3.5 years of the implementation of the law. CONCLUSION: The smoke-free law in Tianjin was associated with reductions in AMI mortality. This study reinforces the need for large-scale, effective and comprehensive smoke-free laws at the national level in China.

'Pro-tobacco propaganda': a case study of tobacco industry-sponsored elementary schools in China.

BACKGROUND: China is the largest producer and consumer of tobacco products worldwide. While direct marketing and advertisement of tobacco products is restricted, indirect marketing still exists under the guise of sponsorship and corporate social responsibility (CSR). This case study is focused on tobacco industry-sponsored elementary schools in Chinese rural areas. METHODS: Field visits were conducted in Yunnan province to interview students, teachers, school principals and parents to understand their perceptions of the tobacco industry and its sponsorship of schools. Interviews with tobacco control activists were conducted in Beijing to discuss national tobacco control efforts targeting tobacco industry sponsorship. Interview data were transcribed and coded, with key themes developed using thematic analysis. RESULTS: While health consequences of smoking are generally known, attitudes towards the tobacco industry and its CSR activities remain positive among the general public. Educators and parents do not perceive any impacts on schoolchildren from exposure to 'pro-tobacco propaganda' created by the industry's CSR activities. Attitudes among tobacco control activists were drastically different, with consensus that CSR activities constitute indirect marketing attempts that should be banned. CONCLUSION: National tobacco control legislation banning all forms of indirect marketing including CSR is needed in order to protect the health of future generations.

Spatiotemporal variations in cardiovascular disease mortality in China from 1991 to 2009.

BACKGROUND: In China, the spatiotemporal variations in cardiovascular disease (CVD) mortality are seldom characterized to understand their epidemiological features. It would be helpful to evaluate the performance of CVD-related interventions for subsequent adjustments. METHODS: The 2010 Census data as well as the coronary heart disease (CHD) and stroke mortality data from the Disease Surveillance Points (DSPs) were used to calculate the age standardized death rates (ASDRs) of CVD in the DSP counties during 1991-1995, 1996-2000, 2004-2005, and 2006-2009. The ordinary kriging (OK) method was used to estimate the county-level death rates of CHD and stroke and achieved satisfactory results. RESULTS: The goodness-of-fit between measured and estimated values of CVD mortality was significant at the 0.01 level (0.34 < R2 < 0.98). The counties with high CHD death rates (> 75 per 105) were located in the Northwest, North, and Northeast in 1991-2000 and then extended toward the North, Central, and South, yielding an inverted-triangle-shaped area in 2004-2009. The counties with a CHD death rate increase greater than 100% were concentrated in the Northeast and South. The Northeast-Southwest regions with a high stroke death rate gradient (> 150 per 105) narrowed in1991-2000, was followed by a slight expansion during 2004-2005, finally reducing in 2006-2009. The counties with a stroke mortality increase greater than 100% were scattered across the Northeast, Northwest, Central, and South. CONCLUSION: The epidemiological characteristics of both CHD and stroke mortality in China was spatiotemporally featured on the county level during 1991-2009.

Spatiotemporal analysis of PM2.5 and pancreatic cancer mortality in China.

BACKGROUND: Previous studies have reported that the development of pancreatic cancer (PC) may be associated with environment pollution. But the relationship between ambient air pollution and PC remains unclear. OBJECTIVES: This study aimed to examine the association between PC mortality and exposure of fine particular matter. METHODS: We used PC mortality data from 103 continuous points in national Disease Surveillance Point system from 1991 to 2009 in China. The annual concentrations of PM2.5 at 0.1°â€¯× 0.1° spatial resolution for each points were estimated based on the context of the Global Burden of Disease Study 2015. A spatial age-period-cohort model was used to examine the relative risks of PC mortality associated with PM exposure, after adjusting gender, urban/rural status, spatial variation as well as age, period and cohort effect. RESULTS: The relative risks of PC mortality related to 10 µg/m3 increase of PM2.5 were 1.16 (95% confidence interval (CI): 1.13, 1.20) for all the population, 1.08 (1.05,1.13) for those aged 40-64 years, 1.21 (1.17,1.25) for those aged 65-84 years, 1.14 (1.10,1.18) for the male, 1.19 (1.14,1.24) for the female, 1.23 (1.16,1.30) for the urban population and 1.29 (1.22, 1.37) for the rural population. CONCLUSIONS: Ambient PM2.5 may raise the risk of mortality from PC, especially in older population. Pollution control policy should be further strengthened to reduce the health damages.

Comment on "Mortality effects assessment of ambient PM2.5 pollution in the 74 leading cities of China" by Die Fang, Qin'geng Wang, Huiming Li, Yiyong Yu, Yan Lu, Xin Qian.

In a recent publication in the journal Science of the Total Environment, Die Fang et al. (2016) reported health effects of current ambient PM2.5 (particulate matters with aerodynamic diameters <2.5µm) pollution in 74 leading cities in China. It is a meaningful original study using the latest air quality surveillance data. However, we suppose their results may over-estimate the long-term exposure-response coefficients for per 10µg/m3 increase in PM2.5 concentration. Moreover, we have concern about the linear relationship the authors assumed for long-term exposure to PM2.5 and the health outcomes. We also have concern about the sufficiency of confounder adjustment. Our suggestions are mainly based on our previous research experience and previous literature. We believe that the debate is conducive to a more accurate and more reasonable estimation of the health effects of PM2.5.

[Risk Factors of Lung Cancer in Xuanwei, Yunnan Province, China].

BACKGROUND: Since 1970s, Xuanwei in Yunnan province has been one of the towns with highest lung cancer mortality in China. Moreover, the characters of high female lung cancer mortality and sub-regional clustering high lung cancer mortality have not changed. In this study, we further described the exposure situation of risk factors of lung cancer in Xuanwei nowadays, in order to explore the trend of the distribution of lung cancer there. METHODS: Firstly we divided the 26 towns of Xuanwei city to high-, median- and low- lung cancer areas by the lung cancer mortality in 2010-2012. We chose 2 towns within each area according to topography and orientation, and randomly picked 4 villages in each town to be our study area. We did a questionnaire about lung cancer related risk factors upon the sample population in the study area. We calculated the exposure percentages of each risk factor, in whole sample population and subgroups, for nowadays and for 10 years ago (only living environmental risk factors), and compared them between areas or time points using standardized rates and the statistical test of standardized rate comparison, or chi-square test. RESULTS: 65%-80% male in the study area has a history of smoking; 60%-90% non-smoker has been exposed to second hand smoke. These situations are worse in high and median lung cancer areas. 50% male in median lung cancer area have coal mining work experience, which is 2 times of the percentages in the other two areas; while 15%-25% people in high lung cancer area have other occupational exposure history to particulate air pollution, which is 3-5 times of the percentages in the other two areas. From ten years ago until nowadays, 80% families in median lung cancer area use 2 tons or more smoky coal per year; more than 90% families burn coal for household heating; more than 60% families suffer from smog in the kitchen during cook; 60% families most frequently use stove in the ground with chimney. Only 20% families in high lung cancer area now use 2 tons or more smoky coal per year. Now 50%-75% families in the study area use 700 kilowatt-hours of electricity per year, much more than ten years ago. 80% residents in low lung cancer area eat fatty or pickled or smoked food at least 3 days per week; while in high and median lung cancer areas the percentages are 50%-60%. CONCLUSIONS: According to data obtained in this survey, current distribution of smoky coal use has differed from the distribution of high-, median- and low- lung cancer areas. Tobacco use and second hand smoke, the use of smoky coal and occupational exposure to particulate matters could be the main risk factors for lung cancer in Xuanwei now. The relations between lung cancer and stove type, dietary habit and so on deserve further study.

Mortality trends for ischemic heart disease in China: an analysis of 102 continuous disease surveillance points from 1991 to 2009.

BACKGROUND: In the past 20 years, the trends of ischemic heart disease (IHD) mortality in China have been described in divergent claims. This research analyzes mortality trends for IHD by using the data from 102 continuous Disease Surveillance Points (DSP) from 1991 to 2009. METHOD: The 102 continuous DSP covered 7.3 million people during the period 1991-2000, and then were expanded to a population of 52 million in the same areas for 2004-2009. The data were adjusted by using garbage code redistribution and underreporting rate, mapped from international classification of diseases ICD-9 to ICD-10. The mortality rates for IHD were further adjusted by the crude death proportion multiplied by the total number of deaths in the mortality envelope, which was calculated by using logrt = a + bt. Age-standard death rates (ASDRs) were computed using China's 2010 census population structure. Trend in IHD was calculated from ASDRs by using a joinpoint regression model. RESULTS: The IHD ASDRs increased in total in regions with an average annual percentage change (AAPC) 4.96%, especially for the Southwest (AAPC = 7.97%) and Northeast areas (AAPC = 7.10%), and for male and female subjects (with 5% AAPC) as well. In rural areas, the year 2000 was a cut-off point for mortality rate with annual percentage change increasing from 3.52% in 1991-2000 to 9.02% in 2000-2009, which was much higher than in urban areas (AAPC = 1.05%). And the proportion of deaths increased in older adults, and more male deaths occurred before age 60 compared to female deaths. CONCLUSION: By observing a wide range of areas across China from 1991 to 2009, this paper concludes that the ASDR trend for IHD increased. These trends reflect changes in the Chinese standard of living and lifestyle with diets higher in fat, higher blood lipids and increased body weight.

Time trends of esophageal and gastric cancer mortality in China, 1991-2009: an age-period-cohort analysis.

Esophageal and gastric cancers share some risk factors. This study aimed to compare the long-term trends in mortality rates of esophageal and gastric cancers in China to provide evidence for cancer prevention and control. Mortality data were derived from 103 continuous points of the Disease Surveillance Points system during 1991-2009, stratified by gender and urban-rural locations. Age-period-cohort models were used to disentangle the time trends of esophageal and gastric cancer mortality. The downward slope of the period effect for esophageal cancer was steeper than that for gastric cancer in rural areas. Cohort effect patterns were similar between esophageal and gastric cancers, with an inverse U-shape peaking around the late 1920s and early 1930s. A second peak, appearing around the 1950s, was weaker than the first but apparent in males, especially for esophageal cancer. The more marked changes in period effect for esophageal cancer in rural areas suggest esophageal cancer screening practices are effective in reducing mortality, and similar programs targeting gastric cancer should be implemented. The similarities of the cohort effects in these two cancers support the implication of nutrition deficiency in early childhood in the development of upper gastrointestinal cancer.

Lung Cancer Mortality and Topography: A Xuanwei Case Study.

The epidemic of lung cancer in Xuanwei City, China, remains serious despite the reduction of the risk of indoor air pollution through citywide stove improvement. The main objective of this study was to characterize the influences of topography on the spatiotemporal variations of lung cancer mortality in Xuanwei during 1990-2013. Using the spatially empirical Bayes method, the smoothed mortality rate of lung cancer was obtained according to the mortality data and population data collected from the retrospective survey (1990-2005) and online registration data (2011-2013). Spatial variations of the village-level mortality rate and topographic factors, including the relief degree of land surface (RDLS) and dwelling conditions (VDC), were characterized through spatial autocorrelation and hotspot analysis. The relationship between topographic factors and the epidemic of lung cancer was explored using correlation analysis and geographically weighted regression (GWR). There is a pocket-like area (PLA) in Xuanwei, covering the clustered villages with lower RDLS and higher VDC. Although the villages with higher mortality rate (>80 per 105) geographically expanded from the center to the northeast of Xuanwei during 1990-2013, the village-level mortality rate was spatially clustered, which yielded a persistent hotspot area in the upward part of the PLA. In particular, the epidemic of lung cancer was closely correlated with both RDLS and VDC at the village scale, and its spatial heterogeneity could be greatly explained by the village-level VDC in the GWR model. Spatiotemporally featured lung cancer mortality in Xuanwei was potentially influenced by topographic conditions at the village scale.

Characterisation of gastric cancer and its relation to environmental factors: a case study in Shenqiu County, China.

This article presents the results of spatial analysis of gastric cancer and its relation to environmental conditions in Shenqiu County, China. Retrospective data on gastric cancer mortality (GCM) were analysed at various spatial scales, with its relation to environmental factors explored at an appropriate scale. The results considered 2 × 2 km(2) grid as the optimal level for characterising GCM due to the highest Moran's I (I = 0.68, p < 0.01). Then, three clustering regions were clearly identified. Meanwhile, GCM was obviously associated with topography (r = -0.11, p < 0.10), farmland (r = 0.11, p < 0.10), population density (r = 0.10, p < 0.10) and river density (r = 0.11, p < 0.10) in the buffered zones. It indicates that spatial grid technique is suitable for characterising GCM in Shenqiu County, and that GCM was geographically associated with environmental conditions. We suggest that preventive measures for controlling the environment-related malignant neoplasm should not be limited in the regions suffering from this disease but be reasonably extended to surrounding areas.

Cause-specific mortality for 240 causes in China during 1990-2013: a systematic subnational analysis for the Global Burden of Disease Study 2013.

BACKGROUND: China has experienced a remarkable epidemiological and demographic transition during the past three decades. Far less is known about this transition at the subnational level. Timely and accurate assessment of the provincial burden of disease is needed for evidence-based priority setting at the local level in China. METHODS: Following the methods of the Global Burden of Disease Study 2013 (GBD 2013), we have systematically analysed all available demographic and epidemiological data sources for China at the provincial level. We developed methods to aggregate county-level surveillance data to inform provincial-level analysis, and we used local data to develop specific garbage code redistribution procedures for China. We assessed levels of and trends in all-cause mortality, causes of death, and years of life lost (YLL) in all 33 province-level administrative units in mainland China, all of which we refer to as provinces, for the years between 1990 and 2013. FINDINGS: All provinces in mainland China have made substantial strides to improve life expectancy at birth between 1990 and 2013. Increases ranged from 4.0 years in Hebei province to 14.2 years in Tibet. Improvements in female life expectancy exceeded those in male life expectancy in all provinces except Shanghai, Macao, and Hong Kong. We saw significant heterogeneity among provinces in life expectancy at birth and probability of death at ages 0-14, 15-49, and 50-74 years. Such heterogeneity is also present in cause of death structures between sexes and provinces. From 1990 to 2013, leading causes of YLLs changed substantially. In 1990, 16 of 33 provinces had lower respiratory infections or preterm birth complications as the leading causes of YLLs. 15 provinces had cerebrovascular disease and two (Hong Kong and Macao) had ischaemic heart disease. By 2013, 27 provinces had cerebrovascular disease as the leading cause, five had ischaemic heart disease, and one had lung cancer (Hong Kong). Road injuries have become a top ten cause of death in all provinces in mainland China. The most common non-communicable diseases, including ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and cancers (liver, stomach, and lung), contributed much more to YLLs in 2013 compared with 1990. INTERPRETATION: Rapid transitions are occurring across China, but the leading health problems and the challenges imposed on the health system by epidemiological and demographic change differ between groups of Chinese provinces. Localised health policies need to be implemented to tackle the diverse challenges faced by local health-care systems. FUNDING: China National Science & Technology Pillar Program 2013 (2013BAI04B02) and Bill & Melinda Gates Foundation.

Increased lung cancer mortality rates in the Chinese population from 1973-1975 to 2004-2005: An adverse health effect from exposure to smoking.

BACKGROUND: Lung cancer incidence and mortality rates have increased substantially in China despite improvements in clinical diagnosis and treatment approaches as well as significant advances in the implementation of tobacco-control policies in recent decades. METHODS: Age-standardized mortality rates and age-specific rates of lung cancer in China were estimated for the periods 1973 to 1975, 1990 to 1992, and 2004 to 2005 using data from 3 National Death Surveys. Among patients with lung cancer who were identified from a hospital-based information system, the percentages of ever-smokers were analyzed according to histologic and demographic variables. RESULTS: Age-standardized mortality from lung cancer in China dramatically increased from 7.30 per 100,000 during 1973 through 1975 to 27.62 per 100,000 during 2004 through 2005. Increases in lung cancer age-standardized mortality were consistent among men and women in urban and rural populations. Among men ages 75 to 79 years, lung cancer mortality increased remarkably to 453.67 per 100,000 in 2004 and 2005 (from 246.78 per 100,000 during 1990-1992 and from 53.65 per 100,000 during 1973-1975). Among 6674 patients with lung cancer who were identified from 2003 to 2007 from a hospital-based database, 82.97% of men were ever-smokers (73.35% of men with adenocarcinoma and 91.8% of men with squamous cell carcinoma), and 11.18% of women were ever-smokers (6% of women with adenosquamous carcinoma and 39.02% of women with squamous cell carcinoma). Differences in the numbers of ever-smokers were observed between age groups but not according to the year of diagnosis. CONCLUSIONS: The consistent and rapid increases in lung cancer mortality rates observed in the Chinese population and the high prevalence of exposure to smoking in China prompt a strong call for the implementation of a comprehensive tobacco-control policy and specific public health educational strategies.

Traffic-related air pollution and lung cancer: A meta-analysis.

BACKGROUND: We conducted a meta-analysis to evaluate the association between traffic-related air pollution and lung cancer in order to provide evidence for control of traffic-related air pollution. METHODS: Several databases were searched for relevant studies up to December 2013. The quality of articles obtained was evaluated by the Strengthening the Reporting of Observational Studies in Epidemiology checklist. Statistical analysis, including pooling effective sizes and confidential intervals, was performed. RESULTS: A total of 1106 records were obtained through the database and 36 studies were included in our analysis. Among the studies included, 14 evaluated the association between ambient exposure to traffic-related air pollution and lung cancer and 22 studies involved occupational exposure to air pollution among professional drivers. Twenty-two studies were marked A level regarding quality, 13 were B level, and one was C level. Exposure to nitrogen dioxide (meta-odds ratio [OR]: 1.06, 95% confidence interval [CI]: 0.99-1.13), nitrogen oxide (meta-OR: 1.04, 95% CI: 1.01-1.07), sulfur dioxide (meta-OR: 1.03, 95% CI: 1.02-1.05), and fine particulate matter (meta-OR: 1.11, 95% CI: 1.00-1.22) were positively associated with a risk of lung cancer. Occupational exposure to air pollution among professional drivers significantly increased the incidence (meta-OR: 1.27, 95% CI: 1.19-1.36) and mortality of lung cancer (meta-OR: 1.14, 95% CI: 1.04-1.26). CONCLUSION: Exposure to traffic-related air pollution significantly increased the risk of lung cancer.

[Investigation on under-reported deaths in Xuanwei Yunnan province, during 2011-2013].

OBJECTIVE: To evaluate the completeness of the death registration system, so as to understand the death patterns in Xuanwei. METHODS: The investigation on under-reported deaths was conducted in 30 villages selected with a multi-stage random sampling strategy. Participants were asked about changes of their family members (family members born or dead) during past 3 years with door to door visit. Then, death cases obtained in our investigation were matched with those from routine death registration system and under-reported rate of deaths during 2011-2013 was calculated employing capture-recapture method. RESULTS: Total under-reported rate of deaths was 31.88%. For people aged between 0-14, 15-39, 40-69 and 60 above, under-reported rates of death were 33.35%, 34.93%, 29.10%, and 32.88%, respectively. And they were 31.72% and 32.02% for males and females, respectively. There was no significant difference shown in under-reported rates among deaths in different age groups (χ² = 7.24, P = 0.065) and genders (χ² = 0.06, P = 0.803). The under-reported rates in high-mortality, medium-mortality and low-mortality regions were 17.48%, 38.01%, and 36.22%, respectively with a significant difference (χ² = 213.25, P < 0.001). Death in local regions with mortality rate higher than 600.00/10(5), between 400.00/105 and 600.00/105 and lower than 400.00/105 were adjusted with under-reported rates in three regions above respectively. The total adjusted morality rate in Xuanwei during 2011-2013 was 776.47/105. For males and females, they were 918.73/105 and 617.46/105, respectively. CONCLUSION: Overall under-reported rate of death was high in death registration system in Xuanwei. It was necessary to adjust mortality data reported with under-reported rate of death to estimate death patterns in this area.

The mortality patterns of lung cancer between 1990 and 2013 in Xuanwei, China.

OBJECTIVES: To explore the variations in the mortality trends, especially death due to lung cancer, from 1990 to 2013 in Xuanwei City. MATERIALS AND METHODS: Mortality data were collected in Xuanwei during the 2nd and 3rd National Retrospective Sampling Survey on Mortality and Routine Death Registration System (DRS) during 2011-2013. According to the result of the survey on under-reported deaths, mortality data from DRS during 2011-2013 were adjusted. Disease specific mortality rate, age-standardized mortality rate (ASMR) and 45Q15 were calculated in Xuanwei and compared with those in rural areas of China. RESULTS: During three periods, 1990-1992, 2004-2005 and 2011-2013, lung cancer contributed to 56.86%, 58.45% and 63.03% of deaths from all cancers respectively with a much higher proportion than rural areas nationally. The ASMR of lung cancer for males surged from 41.43/10(5) to 88.17/10(5) during 1990-2005 and it surged from 37.70/10(5) to 74.45/10(5) for females. Although they declined slightly during 2011-2013 (82.53/10(5) and 62.62/10(5) for males and females respectively), the ASMR of lung cancer among males in Xuanwei was three times of that in rural areas in China, and it was six times higher among females. The 45Q15 of lung cancer for males in Xuanwei was 3-5 times of that in rural areas of China and for females it was 7-9 times. The high-mortality areas of lung cancer were still located in Laibin, Longchang, Wanshui and Shuanglong Communities. High-mortality areas of lung cancer expanded to their surrounding areas and those in southeast. CONCLUSIONS: Although indoor air pollution caused by smoky coal has been fairly well controlled, patterns of death due to lung cancer have not obviously changed. The mortality rate of lung cancer among females was similar to that among males. Therefore, further studies should be conducted to comprehensively explore the risk factors of lung cancer in Xuanwei.

[Cancer prevention and tobacco control].

The paper summarized briefly the evidences for tobacco use as a cause of cancer based on hundreds of epidemiologic and biomedical studies carried out over the past 50-60 years, as well as overviewed the carcinogens in tobacco products and mechanisms of neoplasm induction by tobacco products. So, tobacco control is the important measure for cancer prevention.

The road to effective tobacco control in China.

The non-communicable disease burden in China is enormous, with tobacco use a leading risk factor for the major non-communicable diseases. The prevalence of tobacco use in men is one of the highest in the world, with more than 300 million smokers and 740 million non-smokers exposed to second-hand smoke. In the past decade public awareness of the health hazards of tobacco use and exposure to second-hand smoke has grown, social customs and habits have changed, aggressive tactics used by the tobacco industry have been revealed, and serious tobacco control policies have been actively promoted. In 2014, national legislators in China began actively considering national bans on smoking in public and work places and tobacco advertising. However, tobacco control in China has remained particularly difficult because of interference by the tobacco industry. Changes to the interministerial coordinating mechanism for implementation of the WHO Framework Convention on Tobacco Control are now crucial. Progress towards a tobacco-free world will be dependent on more rapid action in China.