Tuberculosis (TB) has an extremely high global disease burden with more than 10 million new TB cases and approximately 1.7 million TB-related deaths reported annually worldwide [1]. In the Republic of Korea (hereafter Korea), 28,161 new TB cases were reported and the total number of notified patients with TB was 36,044 in 2017. In addition, approximately 2,200 TB-related deaths were reported in 2016 [2].

Since the initial implementation of the national TB control program in health centers throughout Korea in 1962, the government of Korea has legislated the TB prevention law in 1968 to establish the legal basis for the national TB control program. In 1989, a transition from health center- to private hospital-based TB control program began with the introduction of the nationwide health insurance system, and since 2010, significant effort has focused on TB public–private mix (PPM) model. Recently, TB contact investigation has been reinforced and conducted on family members and other individuals who are in close contact with patients with TB as an effort for the early detection of such condition, and this measure is in addition to the significant effort made in the treatment and management of patients with TB, including free TB diagnosis and treatment and allocation of TB-specialist nurses [3]. Consequently, the prevalence, incidence, and mortality rate associated with TB have steadily decreased over the past few decades. Despite such effort, Korea still had high incidence and mortality rates of TB (77 and 5.2 per 100,000 people, respectively) as of 2016, which represents the highest incidence and mortality rates of TB among all member countries of the Organization for Economic Cooperation and Development (OECD) [1].

Accordingly, the government of Korea is planning to establish the 2nd National Strategic Plan for Tuberculosis Control (2018–2022) to implement more intensive TB control policies. Thus, the present study aimed to analyze the incidence, prevalence, and mortality rates of TB in Korea as well as the various TB control policies implemented by the government of Korea over the past few decades to present future improvement measures.

The incidence and mortality rates of TB in Korea reached their peak after the Korean War in 1950 and subsequently showed a rapid decrease (Figure 1). However, the rates are still the highest among all member countries of the OECD [1,2]. The high incidence of TB in Korea despite its high economic standards may be attributed to the Korean War. The outbreak of TB after a war has been observed in other countries as well [13,14], and a significant portion of the Korean population with poor health conditions, such as malnutrition, dense living environment, and low health care accessibility, may have been infected by LTB after the war [3,5]. The LTBI rate in Korea has decreased steadily from 64.2% in 1960 to 59.3% in 1975, to 44.4% in 1990, and to 33.2% in 2016 (Supplementary Material 5). However, the rate is still higher than that of other advanced countries, such as the US [3,8,15]. The high LTBI rate can be considered as one of the biggest barriers in reducing TB in Korea. In 2017, the government of Korea amended the Tuberculosis Prevention Act to make TB and LTBI screening mandatory for specific groups such as health care and postpartum care workers and teachers. Moreover, systematic LTBI screening and treatment were conducted for 1.2 million individuals [3,10] (Supplementary Material 5 and Supplementary Material 10).

Recently, the treatment success rate for patients with TB in Korea has improved due to timely diagnosis and treatment. Of which, patient treatment and management based on the TB PPM model have made a significant contribution, leading to a continuous decrease in the incidence of TB [3]. Moreover, a more drastic decrease was observed in the number of patients with TB in the ≤19-year age group than in any other age groups, which may be attributed to the fact that individuals in this age group were born during the period when the incidence of TB was gradually decreasing and full-scale TB contact investigation and TB screening are being conducted at schools [3,4]. However, the incidence of TB among elderly individuals (≥65 years of age) remains high, and the elderly population accounts for 42% of all patients with TB and 82% of all TB-related deaths in Korea. The elderly population shows a lower TB screening rate than the other age groups, and TB control programs for elderly individuals are limited as well. To address such problems, the government of Korea is planning to establish TB control programs for elderly individuals by implementing pilot programs for TB screening and early detection in 2018. By contrast, TB screening is mandatory for foreigners who are from 19 countries with a high incidence rate of TB and enter Korea for residency or work purposes. However, the management of TB among these foreigners after they have entered Korea is difficult. Accordingly, the government of Korea is also planning to launch a pilot program that examines the performance of TB and LTBI screening among foreigners during their stay in Korea.

The government of Korea established the 2nd National Strategic Plan for Tuberculosis Control (2018–2022) with the goal of lowering the incidence rate of TB from 77 to 40 per 100,000 population by 2022. For the next 5 years, the government of Korea should faithfully execute this plan and allocate the necessary budget according to priorities. First, the top priority for TB control in Korea should be the early diagnosis and treatment of patients with TB. For timely diagnosis and improved treatment rate, health insurance coverage related to TB diagnosis and treatment should be expanded. In addition, to allow timely diagnosis and standardized treatment to be provided at primary care facilities, the reinforcement of the TB PPM program that focuses on medical personnel education and intensive care for patients with TB is also necessary (Supplementary Material 11). Furthermore, research and development efforts for shortening the treatment period and improving the treatment success rate for patients with MDR TB must be expanded. By contrast, measures for the early detection and systematic treatment of TB among the vulnerable population, including elderly individuals, foreigners, and the homeless, who have been neglected until currently, should be explored. With respect to TB treatment for the vulnerable population, a community-based comprehensive public health patient care model should be developed and implemented, whereas greater resources, such as isolation unit for patients with TB and allocation of TB specialist nurses, are also in demand. Second, TB contact investigation should be reinforced to establish an optimal investigation system tailored for collective facilities, such as schools, hospitals, and prisons. The contact investigation should prioritize those in close contact over those in casual contact with individuals with TB, whereas effort is also needed to increase the screening rate for those being tested and treatment success rate for those who tested positive for LTBI [4,12,16-20]. Third, from the TB prevention aspect, promotional strategies must be established for regular TB screening and the timely supply of vaccines by successfully completing the development of TB vaccine that has undergone repeated supply shortage. Moreover, LTBI screening and treatment for high-risk groups including healthcare workers must be continually conducted. Longterm follow-up is needed for LTBI screening and treatment that were performed on 1.2 million individuals in 2017 [12].