The goal of this observational study is to improve access to diagnosis and treatment for chronic Trypanosoma cruzi infection among university students of all ages and genders at the National University of Salta (UNSa), Argentina. The main questions it aims to answer are:

• What is the seroprevalence and geographic distribution of T. cruzi infection in UNSa students?
• Can voluntary point-of-care tests performed at university serve as an effective opportunity for timely diagnosis and linkage to care for Chagas disease?

Participants will:

1. Be offered a RDTs (WL Check Chagas, Wiener Lab) during their regular activities in the university.
2. If RDT is positive, be referred to the health system for confirmatory testing and treatment.
3. Receive follow-up support by trained staff via phone. A subgroup of RDT-negative students will have serum samples preserved and analyzed later via ELISA to verify RDT accuracy.

Background and Rationale Chagas disease is a parasitic infection caused by Trypanosoma cruzi, endemic in Latin America and primarily transmitted by triatomine insects. In Argentina, where vector control has reduced transmission, vertical transmission has become the predominant route. The disease often remains asymptomatic for years but can cause serious cardiac and digestive damage during the chronic phase. Specific treatment is available, especially effective if administered early or before pregnancy in women of childbearing age.

Despite the availability of effective therapy, access to diagnosis and treatment remains limited due to both health system and patient-related barriers. The reported prevalence in Salta province is high: around 5% in blood banks and up to 8% among pregnant women.

The Universidad Nacional de Salta (UNSa), with nine campuses across the province, requires all incoming students to complete a medical check-up. This project leverages that existing requirement to offer rapid diagnostic testing (RDT) for T. cruzi, aiming to identify cases early, link positive individuals to care, and indirectly reach affected families.

The study will be implemented by a multidisciplinary team including researchers in medicine, biology, biochemistry, anthropology, and public health, with institutional support from the Universidad Nacional de Salta, Fundación Mundo Sano, and Salta's Ministry of Public Health.

Objectives

Primary Objectives:

1. Increase access to T. cruzi diagnosis and etiological treatment for chronic infections among university students.
2. Prevent congenital transmission of Chagas disease.

Secondary Objectives:

1. Evaluate the use of RDTs in a point-of-care (POC) approach.
2. Determine T. cruzi seroprevalence and geographic distribution among UNSa students.
3. Promote community awareness and knowledge about Chagas disease.
4. Support public health treatment efforts.
5. Assess treatment adherence and safety.
6. Facilitate screening of family members of positive cases.
7. Explore students' knowledge, attitudes, and practices (KAP) regarding Chagas disease.

Methodology

Design:

Implementation research with mixed methods (quantitative and qualitative components).

Study population All incoming students at UNSa in 2024, across all campuses, regardless of age or gender. In addition, other members of the university community (including teachers, administrative staff, and support personnel) who voluntarily choose to participate.

Sites and Estimated Participants:

In 2023, approximately 23,500 students pre-registered, with ~8,000 beginning courses. Campuses are located in Salta Capital, Tartagal, Orán, Metán, Cafayate, Rosario de la Frontera, Santa Victoria Este, San Antonio de los Cobres, and Joaquín V. González. The estimated number of participants is ~5,000.

Procedures

1. Enrollment:

   The Chagas test is offered on a voluntary basis. At the Salta Capital campus, all first-year students are offered the test during their routine medical examination at UNSa, and other members of the university community may also receive the test whenever they visit the university health office. In the regional campuses, testing is carried out through short, intensive Chagas screening campaigns held in university facilities for several weeks during the year, during which any staff or students may participate. Pre-test information is provided, and participants give informed consent.

2. Testing:

   Chagas RDT (WL Check Chagas, Wiener Lab) is performed via fingerstick.

3. Results:

   Participants are informed of results via phone in case of negative results and on-site in case of positive results. Positive cases are referred to the public health system for confirmatory testing (HAI and ELISA) and evaluation (ECG, clinical assessment), and are also contacted by Mundo Sano staff to support follow-up and answer questions.

4. Epidemiological Survey:

   All participants complete a Knowledge, Attitudes, and Practices (KAP) survey, either through an online questionnaire accessed via a QR code or using a printed version when needed.

5. Family and Entomological Surveillance:

   Public health authorities will follow up with family members of positive cases and conduct home vector inspections when applicable.

6. Evaluation of the Diagnostic Test A validation study will be conducted with 100 negative students to compare RDT results with ELISA testing.

7. Treatment Protocol The public health system guarantees confirmation, notification, free drug provision, and medical follow-up. Drugs used: Benznidazole or Nifurtimox.

Treatment adherence, side effects, and outcomes are monitored. Mundo Sano offer telephone or WhatsApp support during treatment.

Data Analysis The analysis will include both quantitative and qualitative components to comprehensively assess the implementation and outcomes of the study.

Quantitative Analysis Data will be collected on the following variables: 1)Demographics: age, sex, current residence, and birthplace. 2) Epidemiological history: including maternal Chagas status, history of blood transfusions, and contact with Chagas vectors. 3)Diagnostic results: including the result of the rapid diagnostic test (RDT) and confirmatory testing (HAI and ELISA). 4) Clinical outcomes: such as treatment status, adherence, adverse effects, and treatment completion among positive cases. 5) Geographic data: for spatial analysis and visualization of case distribution using Geographic Information Systems (GIS).

Descriptive statistics will be used to summarize both continuous and categorical variables. Comparative analyses will be performed using t-tests or Mann-Whitney U tests for continuous variables, and chi-square tests for categorical variables. Associations between key variables will be explored through bivariate and multivariate logistic regression analyses. Geographic distribution of positive cases will be represented using GIS mapping to identify regional patterns of T. cruzi infection within the province.

Data will be managed and analyzed using Microsoft Excel, R statistics, and EPIDAT 4.2.

Qualitative Analysis Qualitative data will be collected through: 1) Pre- and post-treatment Knowledge, Attitudes, and Practices (KAP) surveys. 2) Observations of selected medical consultations (with participant consent). 3) In-depth interviews and extended case studies with a subset of students diagnosed positive. 4) Focus group discussions to explore experiences of participants diagnosed and treated for Chagas. 5) An evaluation of the patient experience with the public health system following diagnosis and referral.

These qualitative methods will provide insight into participants' perceptions of the disease, barriers to care, adherence to treatment, and the overall acceptability of the intervention. Data will be coded and thematically analyzed to identify key patterns and inform future implementation strategies.

Ethical Considerations Approval from Hospital Señor del Milagro and Salta´s Province Bioethics Committee. Informed consent is mandatory. Participation is voluntary and free of charge. Confidentiality is strictly maintained. Results are not a barrier to university entry or employment (per Argentina's National Chagas Law No. 26.281).

Inclusion criteria:

• Member of the university community (e.g., student, faculty, administrative staff, or other personnel).
• Aged 18 years or older.
• Of any sex or gender.
• Able and willing to provide informed consent.

Exclusion Criteria:

- Prior confirmed diagnosis of Trypanosoma cruzi infection.

Salta is a province in northwestern Argentina where Chagas disease remains endemic. While vectorial transmission has declined in recent years due to control efforts, it has not been fully eliminated. Vertical transmission continues to be a major route of infection. Seroprevalence data indicate that 5% of blood donors and 8% of pregnant women in Salta test positive for Trypanosoma cruzi infection.

The study population includes incoming students at the Nationional University of Salta (UNSa), across its nine campuses located throughout the province. According to UNSa records, in 2023, around 8,000 students began their studies. UNSa is the only public university in Salta, attracting students from across both urban centers and rural areas. First-year students are required to undergo a routine health check, which provides an opportunity for offering Chagas screening. While incoming students are the primary target population, other members of the university are also eligible to participate.

Anonymized individual-level data will be shared, including participants' age, sex, study site (university campus), and results of the rapid diagnostic test (RDT) for Trypanosoma cruzi infection. All data will be de-identified to ensure participant confidentiality, with no personally identifiable information included.

The individual participant data (IPD) will be made available following the completion of the study and the publication of the main results. The anticipated availability period is from December 2025 to June 2026.

Other researchers will be able to access the IPD information if they need it for scientific purposes and make a formal request describing their objectives.