key: cord-0008213-teadzkjs authors: Gibney, Katherine B; Hall, Robert title: Infectious diseases in China in the post-SARS era date: 2017-04-12 journal: Lancet Infect Dis DOI: 10.1016/s1473-3099(17)30168-8 sha: 806cdcbe135d15a111d4136a2022f97e5ec6ae07 doc_id: 8213 cord_uid: teadzkjs nan 2013. 8 The regional committees aim to provide technical assistance to national tuberculosis control programmes. 9 The main efforts of experts from such committees and national tuberculosis programmes should be aimed at using rapid diagnostic methods for drugresistant tuberculosis, providing access to diagnostic tests for all patients, providing appropriate treatment for patients with MDR tuberculosis, and introducing rational approaches in the use of new antituberculosis drugs. 10 The most important measure that might help to prevent the spread of drug-resistant tuberculosis is the implementation of short-course regimens of chemotherapy for patients with MDR tuberculosis. Introduction of 9-12 month courses of MDR therapy will increase the effectiveness of treatment and reduce the total number of antituberculosis drugs during the course of treatment and save funds that can be used to treat more patients. 11 The use of new drugs that correspond with WHO recommendations will improve the quality of treatment for adults and children with drug-resistant tuberculosis and will help to eliminate tuberculosis globally. 12 The epidemiology and comparative burden of commun icable diseases determines which diseases warrant public health resources and intervention. In a country as large as China, identification of the communicable diseases causing the greatest burden and the population groups most affected by specific diseases is a massive, and very important, undertaking. In The Lancet Infectious Diseases, Shigui Yang and colleagues report surveillance data for communicable diseases in China over a 10-year period (2004-13), covering a population of 1·3 billion people and incorporating nearly 55 million notified cases of 45 infectious diseases. 1 Public health surveillance-the so-called cornerstone of public health-has been defined as "the continuous, systematic collection, analysis and interpretation of health-related data needed for the planning, implemen tation and evaluation of public health practice". 2, 3 The 2003 severe acute respiratory syndrome (SARS) epidemic exposed substantial weaknesses in China's national public health surveillance system, which was established in the 1950s. SARS emerged from Guangdong province in southern China, resulting in 5327 cases and 348 deaths in mainland China and an estimated loss of US$25·3 billion to China's economy. 4, 5 In response, China overhauled its approach to public health surveillance and control, with substantial legislative changes, a ten-fold increase in public health funding from 2003 to 2012, and establishment of the largest web-based communicable diseases reporting system in the world. 4, 5 Another key feature of surveillance systems is data availability; the data analysed by Yang and colleagues were available publicly from the Public Health Science Data Center of the A Crump, TDR, WHO/Science Photo Library Chinese Center for Disease Control and Prevention and from the official website of the National Health and Family Planning Commission. 1 A review of notification data in China is timely in this new era of infectious diseases surveillance and publicly available data. Yang and colleagues identified the infectious diseases that warrant public health attention in China, including those with the highest notification incidence (hand, foot, and mouth disease, hepatitis B, and tuberculosis, which together made up two-thirds of all notifications); those with the highest case-fatality ratio (rabies); and infectious diseases with the most rapidly increasing notification incidence (hydatid disease, hepatitis C, and syphilis). Not surprisingly, the highest overall notification incidence was among children younger than 10 years, whereas casefatality ratios increased with age. Males had higher notification incidence and case fatality ratios than did females, indicating a need to target men in preventive and control activities. Wang and colleagues' analyses of seasonality for each of the 45 infectious diseases and notification incidence by province can be used to inform targeted public health interventions by location and season. We all recognise that surveillance data are incomplete and imperfect. Case ascertainment-the proportion of all incident symptomatic cases captured by the surveillance system-varies by disease, location, time, age, and sex. 6 Improved case ascertainment could account for some of the noted increase in overall notification incidence (on average, 6·2% per year from 2004 to 2008 and 2·3% per year from 2009 to 2013), 1 including improvements in the surveillance system and notification process early in the study period. Importantly, 20 infectious diseases, including several vaccine-preventable diseases, showed significantly decreasing incidence over the study period, adding to substantial reductions reported in China from 1970 to 2007. 4 China is participating in the WHO Western Pacific Region goals for polio and measles elimination and hepatitis B control and has made tremendous progress towards these goals. 20 cases of polio were reported among 1·3 billion people over a decade, and incidence is now zero. 1 The prevalence of hepatitis B among young children has declined strikingly, with China achieving the WHO regional target of less than 1% HBsAg seropositivity among children younger than 5 years before the target date. 7 As these children reach adulthood, there will be a profound fall in hepatitis B incidence and associated disease burden. Surveillance data for measles show similar progress but at subnational scales. Measles incidence has declined for age groups in which people have been vaccinated since the elimination goal was declared. 8 To determine the extent of under-ascertainment and bias within the data analysed by Yang and colleagues is impossible. However, the function of surveillance-to inform public health action-can be met by imperfect data. 9 The longitudinal analysis of 10 years of national surveillance data represents a comprehensive picture of the epidemiology of nationally notifiable diseases in modern China. The findings should be used by public health decision makers-both provincial and nationalto prioritise diseases and populations for public health action. Peter Doherty Institute for Infection and Immunity, the University of Melbourne and the Royal Melbourne Hospital, Melbourne, Vic 3000, Australia (KBG); and Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Vic, Australia (RH) katherine.gibney@unimelb.edu.au KG receives salary support from the National Health and Medical Research Council (NHMRC) of Australia and received the NHMRC Gustav Nossal Scholarship sponsored by CSL in 2012; this award is peer-reviewed and CSL does not play any part in selection of the awardee. RH declares no competing interests. Epidemiological features of and changes in incidence of infectious diseases in China in the first decade after the SARS outbreak: an observational trend study The cornerstone of public health practice: public health surveillance World Health Organization. Health topics: public health surveillance Emergence and control of infectious diseases in China Pains and gains from China's experiences with emerging epidemics: from SARS to H7N9 Measuring underreporting and under-ascertainment in infectious disease datasets: a comparison of methods Epidemiological serosurvey of hepatitis B in China: declining HBV prevalence due to hepatitis B vaccination World Health Organization Western Pacific Region. Country profile: measles elimination-China Surveillance of smallpox