This two-phase, mixed-methods approach project aims to develop a community-based, participatory, and co-created TB/TB infection (TBI) screening care pathway for African and Hindustan immigrants, who often face socioeconomic vulnerabilities and barriers to healthcare access, including TB/TBI screening. The first phase involves the co-design of a TB/TBI screening care pathway through four thematic workshops using the Double-Diamond theoretical framework. These workshops will engage key stakeholders, including immigrants, community leaders, healthcare professionals, and academics, to identify barriers, define needs, and develop actionable measures to improve TB/TBI screening care. The second phase involves a community-based study to implement the care pathway and estimate the incidence of TB and TBI among 200 immigrants from Angola, Cabo Verde, Guinea-Bissau, Mozambique, India, Bangladesh, and Nepal. Participants will be recruited through Grupcommunity services, and data will be collected on demographic, socioeconomic, health, and migration-related factors. The screening pathway will be implemented and evaluated, with patient-related outcomes measured to assess its effectiveness. The primary outcomes include the development of a culturally sensitive TB/TBI screening care pathway and the estimation of TB and TBI incidence among high-risk immigrant populations. Secondary outcomes include the profiling of immigrant populations, the identification of social vulnerabilities, and the establishment of eligibility criteria for TB/TBI screening in similar populations. We expected to advance knowledge on the specific needs of vulnerable immigrants regarding TB/TBI screening and care and to empower communities, improve access to healthcare, and inform policymakers on tailored prevention and control strategies. The findings will contribute to the global effort to eliminate TB by addressing the unique challenges faced by immigrant populations in low-incidence countries like Portugal.

Tuberculosis (TB) is an infectious disease primarily affecting the lungs but capable of spreading to other organs. Following infection, around 5% of those infected develop the disease in the first 2 years, while the others carry the bacteria but remain asymptomatic. TB infection (TBI) occurs when individuals are infected but do not show symptoms and are not contagious. In 2022, there were 10.6 million cases of TB, 1.3 million deaths due to TB worldwide and approximately 1.7 billion people globally were estimated to have TBI, representing a significant pool of potential future TB cases. Preventive treatment for TBI is crucial to reducing the risk of progression to active TB and is a key component of the World Health Organization's (WHO) End TB Strategy. Early diagnosis, effective treatment, and targeted interventions for groups at increased risk are essential to controlling both TB and TBI globally.

The number of TB cases in Portugal has been gradually decreasing. In 2016 the country was considered a low-incidence country (<20 TB cases per 100,000 inhab). Immigrants are among the groups experiencing higher TB burden, especially in low-incidence countries, dure to factors such as overcrowding, poor living conditions, and limited healthcare access during migration trajectory and in refugee camps. Immigrants accounted for 30.1% of TB cases in Portugal in 2022, with a notification rate 4 times higher than the national average (58.5 cases/100,000 inhab). The majority of TB cases in immigrants were from Angola, Brazil, Guinea-Bissau, and Cape Verde. In 2023, the number of immigrants increased by 34% compared to 2022 with more than a million documented immigrants living in the country and an estimated number of undocumented immigrants between 30,000 and 50,000. Seven of the nine most common nationalities of newly arrived immigrants are from high TB burden regions like Africa and Hindustan, i.e., Angola, Cape Verde, India, Guinea Bissau, Bangladesh and Nepal.

In Portugal, the current guidelines for TB surveillance and management identify immigrants as one of the key populations for targeted intervention and establish those from high incidence countries (i.e., Angola, Guinea-Bissau, Cabo Verde, Mozambique, Ukraine, Romania and Russia) should be screened. However, immigrants from Hindustan countries are not included despite growing significance in current immigration trends.

The overall aims of this project are to develop a community based, participatory, co-created TB/ TBI screening care path, to estimate the incidence of TB and TBI in African and Hindustan immigrants in Portugal and to understand how some of their social, health and economic vulnerabilities may influence TB risk and adherence to a cascade of TB/TBI screening care.

Aim: to develop a co-created TB/TBI screening care path to ensure immigrants are not left behind and that no one is left untreated.

A two-phase sequential, mixed-methods approach was designed. The first phase pertains to i) Co-Creation of a TB/TBI Screening Care Path: Developing a culturally sensitive TB/TBI screening care pathway for immigrants; and the second phase to ii) Care in Motion: Community-Based Study: Implementing and evaluating the care path through a community-based survey.

i) Co-Creation of a TB/TBI Screening Care Path: Developing a culturally sensitive TB/TBI screening care pathway for immigrants Phase I will bring together the team and stakeholders closely involved in the research project, particularly from community services and TB dedicated health services to review the team's principles, clarify members' roles, identify bottlenecks and facilitators, and discuss the team's vision for the future. This vision will focus on what the team aims to achieve regarding TB and TBI screening among immigrants. This initial step will help the team "see the bigger picture" and position the team to work differently. It will also facilitate a more effective and holistic mapping of existing and potential stakeholders to include in the co-creation process. The outcomes of this activity (team roles, future vision, and stakeholder mapping) will support the following four thematic workshops (WS): WS1 Discover, WS2 Define, WS3 Develop, and WS4 Deliver.

All stakeholders identified in the stakeholder mapping exercise will be invited to participate in the four workshops. The workshops will take place in an open, friendly, and safe environment where everyone feels free to participate. Discussions will be guided using a semi-structured script to direct the conversation. All participants will be invited to share their views in turn, ensuring a more inclusive experience.

In WS1, a root cause analysis will be used to systematically explore events (what happens), patterns (trends), structures (what enables patterns and trends to persist), and mental models (what makes these structures possible) related to TB and TBI screening among immigrants. Building on the results of WS1, in WS2 the problem under analysis will be reframed, challenging the current way of thinking. This will be done using a different perspectives approach (e.g., how to change the approach, what might be possible, what might be difficult). In WS3, stakeholders will be invited to create a series of new and innovative activities concerning TB and TBI among immigrants, with a particular focus on surveillance care, using a portfolio of ideas. Finally, in WS4, the prototype for the TB/TBI screening care pathway for immigrants will be developed, incorporating ideas that emerged during the previous workshops. To accomplish this, a Radical Innovations approach will be used.

ii) Care in Motion: Community-Based Study: Implementing and evaluating the care path through a community-based survey In the second phase of the project, the co-created TB/TBI screening pathway will be implemented. Community researchers will be recruited and will work closely with community services working with the targeted population. These researchers will be responsible for recruiting participants, collecting data and guiding participants through the TB/TBI care path, and will primarily be selected from the African and Hindustan communities. If feasable, recruitment will take place before the workshops of phase 1, allowing these researchers to also participate in the co-creation process. Researchers from the African community will need to speak Portuguese and Creole, while researchers from the Hindustan community will need to speak English and one or more of the following languages: Hindi, Urdu, Nepali, or Bengali. This linguistic diversity aims to reduce language barriers during the implementation of the TB/TBI screening pathway. Community researchers will receive training from the research team on the screening pathway and data collection procedures.

Over a 6-month period, 200 participants will be consecutively be recruited among users of the community services. These participants will be invited to take part in the TB/TBI screening pathway. The number of participants has been determined based on the capacity of the TB dedicated health care services to conduct TB/TBI screenings for all participants within the study period, as well as to provide treatment as necessary. Participants must be 18 years or older, have started their migration journey less than 5 years ago, and be nationals from Angola, Cabo Verde, Guinea-Bissau, Mozambique, India, Bangladesh, or Nepal. Immigrants with a legally designated representative will be excluded from the study.

Upon signing the informed consent form, participants will begin the TB/TBI screening care pathway. An electronic survey designed in RedCap to collect data on demographic and socio-economic characteristics, living and housing conditions, migration journey, clinical and epidemiological profile, substance use, and TB/TBI risk will be used. All participants will be invited to follow the TB/TBI screening pathway and will be offered IGRA test at TB dedicated health services as well as other medical exams needed to confirm or further study their clinical condition and according to their needs. Participants diagnosed with TB/TBI during the study will be treated by the TB dedicated health service according to Portuguese National Guidelines.

Primary outcomes: Incidence of TB and TBI, Performance of TB/TBI risk questionnaires relative to screening tests, Immigrant-related outcomes Secondary outcomes: Immigrant profile (demographic, socio-economic, migration journey, health), Prevalence of other social vulnerabilities This project will allow first glimpse of some of the socioeconomic and health issues faced by the African and Hindustan immigrant community. It utilizes a culturally adequate and participatory methodology to address a problem identified by relevant stakeholders and will co-create a solution, boosting communities' awareness and empowerment, as well as partners' responsiveness towards TB prevention.

Inclusion Criteria:

- adult immigrants, aged 18 years or older, from Angola, Cape Verde, Guinea-Bissau, Mozambique, India, Bangladesh, or Nepal, who began their migration journey less than five years ago, who attend or are identified through community services or associated community networks, and who agree to participate by signing an informed consent form.

Exclusion Criteria:

• Participants with a legally appointed representative
• Participants incapable of understanding essential study information, even with linguistic or cultural mediation support and with any clinical condition that prevents the interview, informed consent, or screening process

We will use a sequential non-probability sampling method. Eligible participants will be recruited consecutively from community services in Lisbon and associated community networks during the defined data collection period, until the planned sample size is reached or until the end of the recruitment period (6 months after the first workshop).

We plan to include approximately 200 participants. This sample size was determined by the operational capacity of the services involved, specifically capacity for community recruitment and participant follow-up, and the capacity of the TB community services for clinical evaluation, diagnosis, treatment decisions, and follow-up when necessary.