Tuberculosis (TB) is an infectious disease that is still a public health problem in the world. TB is caused by the bacterium Mycobacterium tuberculosis, which primarily affects the lungs and is transmitted via airborne droplets. The World Health Organization (WHO) has tried to reduce TB's prevalence, incidence, and mortality rates. However, this infectious disease is still the top cause of death globally after COVID-19. The number of deaths from tuberculosis in 2019 was found to be around 1.2 million and has increased in 2020 to 1.3 million deaths (WHO, 2022). Nearly a quarter of the world's population has been infected with tuberculosis, with approximately 89% occurring in the adult and another 11% in children (WHO, 2022). In the Global Tuberculosis Report 2022, Indonesia is included in eight countries that account for two-thirds of the total tuberculosis cases in the world, with an estimated number of TB cases reaching 824,000 and the number of deaths totaling 93,000 or the equivalent of 11 deaths/hour. According to the Director of Communicable Disease Prevention and Control (P2PM) of the Indonesian Ministry of Health, of the estimated % of TB cases in Indonesia, only 49% have been found and treated. This indicates that around 500,000 other people have not been found, putting them at risk of becoming a source of transmission (Kemenkes RI, 2022). East Java Province is recorded as the third highest tuberculosis case nationally, with the number of cases in 2021 reaching 43,247 (Dinas Kesehatan Provinsi Jawa Timur, 2021). Based on BPS East Java data in 2020, Malang Regency was ranked 5th with the highest number of tuberculosis cases, totaling 1,807. In addition, the Treatment Coverage (TC) percentage in Malang Regency is only around 29%, indicating that many TB cases have not been reached by the program (Dinas Kesehatan Provinsi Jawa Timur, 2021).

Tuberculosis cases that have not been fully treated will affect the severity and increase cases due to transmission, where each patient can potentially infect 10 to 15 people (Budi et al., 2018). One of the selected SDGs monitoring TB incidence is ensuring access to adequate, safe, and affordable housing for the proportion of the urban population living in slums, informal settlements, or inadequate housing (WHO, 2022). Living in slums is a risk factor for TB transmission that is associated with disease progression. As many as 91% of active TB cases in Indonesia can be transmitted and attack healthy people around them, especially in slums, dense areas, and poor PHBS (Clean and Healthy Living Behavior) practices (Kemenkes RI, 2022). In a study by Lee et al. (2022), low-quality housing has a higher risk of TB development, which is associated with exposure, transmission, and incidence of TB. Poor housing quality indicates an inadequate indoor environment, such as house density, ventilation, lighting, and humidity. This is also supported by the research of Apriliani et al. (2020), who found that the physical condition of the house, which includes ventilation, roof condition, lighting, occupancy density, temperature, humidity, type of wall and floor of the house showed a relationship with the incidence of tuberculosis in the Simomulyo Health Center working area of Surabaya City.

The physical components of the house are part of the criteria for assessing healthy homes in the Healthy Indonesia Indicator Environment Program 2010. One of the goals of this program is to achieve settlements that meet health requirements in handling slums in urban and rural areas. The Environment Program aims to comprehensively maintain and improve the health of individuals, families, and communities by creating a healthy environment. Environment or physical environment is an external factor that can cause disease in the community (Mahendrani et al., 2020). The occurrence of environmental shifts can make it easier for bacterial agents to attack the population or make the population vulnerable to disease. In this case, the home environment that interacts constantly with the population becomes a determinant that affects the health conditions of its residents (Purwaningrum et al., 2018). Healthy housing coverage is part of the ecological aspect in describing the quality of settlements in an area (Dewi et al., 2019). Based on Minister of Health's Decree No. 829/Menkes/SK/VII/1999, healthy housing requirements are determined based on the physical components of the house, occupancy density, presence or absence of infectious animals, waste disposal facilities, sanitation, and food storage.

In East Java Province, the Healthy Homes program has not yet reached the national achievement target of 80% (Dinas Kesehatan Provinsi Jawa Timur, 2018). Malang Regency has the second-highest housing density in East Java (BPS, 2019). Hence, health risks and exposures in the home environment must be considered because people spend most of their time at home (Purwaningrum et al., 2018). According to Ministry of Health Regulation 67/2016, control of tuberculosis risk factors is carried out by maintaining and improving the quality of housing and its environment according to healthy housing standards. In this case, housing that does not meet health requirements can be a risk factor for tuberculosis transmission (Wulandari et al., 2015).

Previous studies on housing conditions have primarily focused on specific components associated with the incidence of tuberculosis. Research conducted by Apriliani et al. (2020) showed a significant relationship between the variable components of the physical condition of the house and the incidence of tuberculosis. Hence, a spatial and correlative study of healthy house coverage needs to be conducted. The study of healthy house coverage associated with the incidence of tuberculosis will provide an overview of the quality of housing in an area towards tuberculosis cases in the population as a whole. Puskesmas (Community Health Center), as a unit organizing public health efforts, plays an important role in improving the quality of health status in a promotive and preventive manner. Health services in each region have differences in health organization, but in essence, these efforts have the same goal of improving optimal health status. The health center, which is the subject of direct intervention, is responsible for health maintenance in its working area.

Spatial analysis and correlation of healthy house coverage to the incidence of tuberculosis in the working area of Puskesmas in Malang District has never been conducted. In addition, the healthy housing program, which has a general objective of improving health status, has never been directly linked to the incidence of tuberculosis in the Malang District Health Office. Considering that Malang District is the region with the top 5 highest TB cases and the second densest number of housing settlements in East Java, there is urgency in the research. This study will map and examine the correlation between the coverage of healthy houses and the incidence of tuberculosis in the Malang District Health Center working area in 2019-2021, where there is still no research that analyzes conditions in the last 3 years in aggregate. This study was conducted to determine the trend and level of correlation between the coverage of healthy houses and tuberculosis cases in the working area of the Malang District Health Center, which is expected to provide a preliminary overview of key determinants of the control program and prevention of tuberculosis transmission in at-risk areas in the future.

The univariate analysis (Table 1) shows that the average incidence of BTA-positive pulmonary TB in the Malang District Health Center Working Area for 3 years was 28.77 per 100,000 population. In 2019, the minimum value of TB incidence was 14.84 per 100,000 population, and the maximum was 58.62 per 100,000 population. The minimum TB incidence value 2020 was 5.31 per 100,000 population, and the maximum was 54.93 per 100,000 population. In contrast, in 2021, the minimum TB incidence rate was 2.93 per 100,000, and the maximum was 42.95 per 100,000.

The incidence rate reflects new and relapsed TB cases reported within a specific period (Kemenkes RI, 2016). Nationally, the TB incidence reduction target commitment developed by the Ministry of Health is ≤65 cases per 100,000 population (Kemenkes RI, 2020). This shows that the incidence of BTA-positive pulmonary TB in the work area of the Malang District Health Center is far from meeting the national target. TB control efforts are directed at accelerating elimination and ending the TB epidemic in Indonesia. Thus, the persistence of the TB incidence rate indicates the possibility of close contact cases that could be a risk of transmission. TB case-control in Indonesia is based on the DOTS (Directly Observed Treatment Shortcourse) strategy that focuses on case finding in TB patients (Mayopu, de Fretes, & Tauho, 2022). This strategy implements active and passive case findings of pulmonary TB patients. Active case-finding is done through contact case investigation and screening, while passive case-finding is done when patients visit health facilities. Implementing the DOTS strategy is highly dependent on infrastructure in the case of pulmonary TB patients (Inayah et al., 2019). The low case-finding rate of pulmonary TB can be caused by a surveillance system that is not yet strong, the lack of capacity to diagnose the disease, and the lack of community access to health services (Rejeki et al., 2019).

In the Healthy Indonesia Indicators 2010, the target percentage of healthy homes is 80%. The average coverage of healthy homes in the Puskesmas work area of Malang District for the last 3 years in Table 1 is 77.82%, with the highest coverage in 2021 at 87.86%, followed by 2020 at 76.79% and the lowest in 2019 at 68.81%. In 2019, the minimum value of the percentage coverage of healthy homes was 17.45%, and the maximum was 97.65%. The minimum value of healthy home coverage in 2020 is 32.01%, with a maximum value of 98.97%. Meanwhile, in 2021, the minimum value is 63.33%, and the maximum is 100%. This indicates that healthy home coverage in Malang District has not fully met the national target. A healthy home refers to the physical structure of a dwelling, the extent to which it structurally enables physical health by providing shelter from elements of humidity, temperature, sanitation, lighting, and sufficient space capacity (WHO, 2018). Housing suitable for living must meet health requirements to protect residents and the community from danger or health problems. Poor housing conditions will cause health problems and disease transmission (Budi et al., 2018). Research conducted by Susanna & Achmadi (2019) states that assessing healthy homes in the field is only done on several houses. The high and low percentage of healthy homes is influenced by the condition of the assessed house (Olivionita et al., 2022). The conditions of the COVID-19 pandemic have also impacted health services at the Puskesmas. The existence of a pandemic causes changes in the internal policies of each Puskesmas in running the program (Hasanah et al., 2020). Special management strategies are sought to ensure the quality of health services and protect the community and health workers from exposure to COVID-19.

Mapping the Distribution and Trends of Incident Cases of BTA Positive Pulmonary TB

Research by Cilloni et al. (2020) states that tracking patient contacts in discovering new TB cases is hampered during the Covid-19 pandemic. This is because resources related to all aspects of the healthcare system are maximized and focused on handling the pandemic (Damaranti et al., 2023). These limitations have an impact on TB management programs that were previously routinely carried out to be hampered. The transfer of TB diagnostic tools used for COVID-19 testing hindered case finding, thus affecting the decline in TB case notification (Togun et al., 2020). In addition, the implementation of regional quarantine causes people to delay visits to health facilities, which causes delays in TB diagnosis (Kant et al., 2021).

Referring to Figure 2, concentrated zones indicate a high concentration of cases, while bright zones indicate low cases. The distribution of high-incidence cases of BTA-positive pulmonary TB in 39 Puskesmas in Malang District is characterized by areas that have more concentrated zones (≥29) and low cases with lighter zones (<29). In 2019 (a), 24 Puskesmas were in the high case zone, and 15 Puskesmas were in the low case zone. By the end of 2021, areas with high case zones will be reduced to 15 health centers and low case zones to 24 health centers. The results show that the condition of the BTA Positive Lung TB Incident in Malang District has gradually improved from year to year. 9 Puskesmas are always in the high incidence zone, including Puskesmas Gondanglegi, Bululawang, Donomulyo, Ketawang, Pakisaji, Sumbermanjing Kulon, Turen, Wagir, and Wonokerto. The population distribution pattern in these nine areas has a higher productive age group population composition than other areas. According to the Ministry of Health, TB cases are primarily found in the productive age group (Kemenkes RI, 2023). This is because the productive age group has high mobility and social interaction compared to other age groups, allowing tuberculosis transmission (Pramono, 2021). Most of the 9 Puskesmas areas are also rural (Hardiyanti et al., 2018; Wijayanti et al., 2019). In Indonesia, the findings of perceived ease of access to health centers in urban communities are easier than in rural areas. According to Radandima et al. (2020), treatment coverage in urban areas will be easier regarding access to health services. Some of these Puskesmas have SPM percentages of less than 70%. These percentages indicate that the achievement of Puskesma's performance in providing standard services for people suspected of TB is not optimal. The severity of the disease affects the quality of life of the patient. This disease requires attention and care from various sectors to improve treatment compliance so that patients' quality of life is improving, reducing the risk of transmission.

The direction of this relationship indicates that the higher the coverage of healthy homes, the lower the incidence of BTA-positive pulmonary TB. This aligns with research by Susanna & Achmadi (2019), which found no significant relationship between healthy home coverage and TB incidence. Referring to the previous graph, the trend of both variables shows that the coverage of healthy homes is improving, followed by a low incidence of TB. However, from the classified distribution, Puskesmas working areas with good house coverage with high incidence are more than those with low zones. Then, some areas with poor house coverage are in the low incidence category. The spatial analysis results show no relationship between the coverage of healthy homes and the incidence of BTA Positive Pulmonary TB in the Puskesmas Working Area of Malang District.

Based on research by Apriliani et al. (2020), the physical conditions of the house that affect the proliferation of TB bacteria include occupant density, lighting, ventilation, flooring, humidity, and temperature. However, this may be due to the fact that not all indicators of healthy home coverage are directly related to TB incidence.

This study is limited to Temporal Ambiguity, where the results cannot prove that the exposure preceded the disease. The secondary data used in the study makes limited information from existing data. The results of population-based or aggregate ecological studies cannot represent each individual, so the presence or absence of a relationship at the population level is not necessarily the same at the individual level. However, this study can serve as a strategy for policymakers to determine which health centers should focus on strengthening TB management and intensifying TB case findings. Puskesmas needs to detect, monitor, and treat TB cases in the long term. Capacity building for TB services such as drug distribution and increasing and training the number of health workers and drug swallowing supervisors at risk health centers is very influential in eliminating TB cases (Amaliyah & Wahyono, 2021). The involvement of health workers and community groups such as cadres and PMOs contributes to increasing awareness and knowledge about TB, so the mapping in this study helps determine achievement targets at each Puskesmas. The PHBS (Clean and Healthy Lifestyle) program intervention seeks to empower the active role of each household in practicing clean and healthy living behaviors (Natsir, 2019). Advocacy, community development, and community movement approaches in PHBS can improve knowledge, attitudes, and behaviors, optimizing the quality of health in each Puskesmas. Community involvement in efforts to practice PHBS plays a role in helping to prevent TB transmission.

The findings of this study, from both trend and spatial analyses, show that while the coverage of healthy homes tends to increase, the incidence of TB does not always decrease significantly in all regions. These findings suggest that while housing conditions contribute to TB risk, they do not independently account for observed transmission patterns, highlighting the need to consider broader social and behavioral determinants. This result is consistent with the social ecology theory of public health, which states that determinants of health include structural, environmental, and individual behavioral factors. Therefore, it is important to consider the interaction between various determinants in understanding the spread of TB in a region.

The data used in this study are secondary data obtained from the Malang District Health Office and the Malang District Statistics Center Agency for the 2019-2021 period. The data is not publicly available but can be accessed upon reasonable request by the correspondence author with permission from the agency that owns the data.

This research did not receive external funding.

The authors declare that there is no potential conflict of interest in conducting this research or in preparing this scientific article.