OBJECTIVES:To evaluate continuity of once-weekly isoniazid plus rifapentine for 12 weeks (3HP) tuberculosis preventive treatment in a Paraguayan prison cohort, focusing on adherence, strict completion, safety and institutional transitions as drivers of non-completion. METHODS:We conducted a longitudinal implementation cohort study at Coronel Oviedo Penitentiary Center, Paraguay, during July-October 2025. Persons with QuantiFERON-TB Gold Plus-confirmed tuberculosis infection and active tuberculosis excluded by the program algorithm were offered 3HP under directly observed therapy. Weekly dose administration, missed-dose reasons and self-reported adverse reactions were recorded. RESULTS:Of 1846 people incarcerated in the facility, 240 accessed QuantiFERON testing and 170 tested positive. Among QFT-positive individuals, 50 did not initiate 3HP because of transfer, release or refusal. A total of 120 initiated 3HP; 90 achieved acceptable adherence, defined as receipt of at least 11 of 12 doses (75.0%), and 82 completed all 12 doses (68.3%). Medication was administered in 1195 of 1440 scheduled person-weeks (83.0%). Non-completion occurred in 30 participants; 28 cases (93.3%) were attributable to release or transfer. Fifty-seven participants (47.5%) reported at least one adverse reaction, mostly mild or moderate. CONCLUSION:High adherence was achieved with 3HP, but institutional transitions interrupted completion, highlighting the need for prison-to-community continuity mechanisms after incarceration.

Background:Tuberculosis infection affects an estimated one-quarter of the global population and represents a key target for TB elimination strategies. While interferon-gamma release assays (IGRAs) such as QuantiFERON-TB Gold Plus (QFT-Plus) are WHO-endorsed, they remain logistically complex in low-resource settings. This study evaluates the performance of the AFIAS IGRA-TB, a qualitative fluorescence immunoassay (FIA), compared to QFT-Plus in Paraguay. Methods:A cross-sectional diagnostic accuracy study was conducted from January to May 2025 among 210 individuals aged 18-59 years within the Barrio Obrero healthcare network in Asunción, Paraguay. Participants were stratified into three TB risk groups: low-risk (no known exposure), high-risk (close contacts and incarcerated individuals), and active TB cases. Blood samples were tested with both AFIAS and QFT-Plus assays. Discordant results were retested after six to eight weeks. Concordance was assessed using Cohen's Kappa; quantitative correlations and ROC curves were also analysed. Results:Of 210 participants, 75.2% were male. Overall positivity rates were 38.5% for QFT-Plus and 37.0% for AFIAS, with an agreement of 89.0% (κ = 0.767; p < 0.0001). Strong concordance was observed in high-risk groups. Among 23 discordant cases, retesting confirmed the initial AFIAS result in 5 cases and QFT-Plus in 3; 7 remained discordant. Spearman correlation showed strong, significant association between quantitative values. ROC analysis yielded an AUC of 0.890 for AFIAS. Conclusion:AFIAS IGRA-TB demonstrates comparable performance to QFT-Plus with operational advantages, suggesting it is a viable diagnostic alternative for TB infection, particularly in decentralized or resource-limited settings.

Introduction:Accurate diagnosis of tuberculosis (TB) infection is essential for TB control, particularly in high-risk populations. Interferon-gamma release assays (IGRAs) are widely used for TB infection screening. This study assesses the diagnostic agreement between the STANDARD™ F TB-Feron fluorescence immunoassay (FIA) and the WHO-approved STANDARD E TB-Feron ELISA in penitentiary settings in Paraguay. Methods:A cross-sectional study was conducted among 737 participants (642 incarcerated individuals and 95 staff members). Both assays were performed on the same blood samples from each participant. Agreement was assessed using the Kappa coefficient, with stratified analyses across predefined risk groups: G1, no known TB exposure (n = 71); G2, TB exposure (n = 525); G3, active TB (n = 67); and G4, previously treated and cured TB (n = 74). Results:Overall positivity was 57.7% with FIA and 56.9% with ELISA. Positivity rates for FIA/ELISA were: G1 (22.9%/22.9%), G2 (57.7%/58.4%), G3 (79.1%/79.1%), and G4 (71.6%/71.6%). Overall agreement was excellent (κ = 0.851; 95% CI: 0.812-0.889; p < 0.0001). Stratified analyses showed moderate agreement in G1 (κ = 0.595) and excellent agreement in the remaining groups. Conclusion:The STANDARD F TB-Feron FIA demonstrated excellent concordance with ELISA, supporting its use as a reliable alternative for TB infection screening. In addition, the FIA offers key operational advantages, including reduced hands-on time (approximately 15 min compared with several hours for ELISA), the ability to process single samples without batch runs, and the use of portable equipment requiring less laboratory infrastructure, making it particularly suitable for decentralized and resource-limited settings.

Tuberculosis (TB) and human immunodeficiency virus (HIV) cause significant morbidity and mortality in South America. Despite the advances in active case finding and early treatment initiation as core strategies to decrease TB and HIV transmissions, additional efforts are needed to achieve control and eventual elimination of these 2 epidemics. Availability and implementation of preventive strategies using shorter, rifamycin-based regimens for TB preventive therapy and long-acting injectables for HIV prevention are still a challenge in the South American region. In this report, we discuss opportunities to accelerate TB and HIV prevention in the region. We present examples of novel TB and HIV surveillance and prevention initiatives among high-risk groups and vulnerable populations in countries within the region, using precision public health approaches and leveraging digital health and artificial intelligence tools. Finally, we propose a roadmap for ending TB and HIV in South America.

Objective:To establish baseline seroprevalence of soil-borne, waterborne, and foodborne diseases and to monitor diseases that are eliminated or on the path to elimination in the Paraguayan Chaco. Methods:A total of 1 100 school-age children (6-15 years) were tested in urban and rural schools selected for a cross-cutting population-based survey using a two-stage probabilistic sample design in the three departments of the Paraguayan Chaco. Blood samples were taken on filter paper to measure IgG antibodies using a multiplex bead assay. Data collection was carried out through interviews with parents and caregivers. Access to basic sanitation and improved water was assessed. Differences in pathogen seropositivity and seroprotection were estimated by urban and rural areas. Results:Seroprotection against measles was 62.9% and against rubella was 78.2%. Minimal diphtheria and tetanus seroprotection (≥0.01 IU/ml) was 92.9% and 98.3%, respectively. Seroprotective levels against these four vaccine-preventable diseases significantly decreased with increasing age (p < 0.05). The following pathogens and respective antigens showed significantly higher seroprevalence (p < 0.05) in rural areas compared with urban areas: Cryptosporidium parvum Cp17: 80.4% vs 64.6%, and Cp23: 60.6% vs 44.8%; Giardia lamblia VSP3: 26.9% vs 16.6%; Strongyloides stercoralis NIE: 11.5% vs 4.1%; and Taenia solium T24H: 7.1% vs 1.6%. Seroprevalence for these pathogens was also higher in Indigenous population when compared to non-Indigenous. Basic sanitation conditions showed significant differences (p < 0.05) between rural and urban areas: adobe and soil dwelling floor (65.3% vs 30.2%), use of pit latrine (90.3% vs 44.2%), availability of drainage or septic tank (8.7% vs 55.2%), access to safe water (19.7% vs 44.9%), and water treatment (6.8% vs 32.3%). Conclusions:We identified high exposure to soil-borne, waterborne, and foodborne diseases in rural areas and Indigenous population in the Paraguayan Chaco. Low seroprotection against measles and rubella alerts about the risk of immunity gaps to maintain elimination targets.

Background:While over the past decade global incidence rates of tuberculosis (TB) have decreased, in Paraguay incidence has risen. A new reporting system implemented in 2018 has not previously been used to characterise trends in TB and identify areas to prioritise for the expansion of access to TB diagnostics and treatment programmes. Methods:We conducted a retrospective study of all TB cases notified to the Paraguay National Program for Tuberculosis Control (NPTC) from 2018 to 2022. We quantified trends in case notifications spatially and in specific populations identified as vulnerable by the NPTC and measured trends in access to GeneXpert testing. Findings:Of the 13,725 TB cases notified in Paraguay from 2018 to 2022, 2337 (17%) occurred among incarcerated individuals and 1743 (12.7%) occurred among self-identified Indigenous individuals. In 2022, the relative risk of TB was 87 and 6.39 (95% CI: 6.08-6.72) among persons deprived of liberty and Indigenous populations, compared to those who are not persons deprived of liberty and non-Indigenous populations respectively. We found significant heterogeneity in TB incidence across Paraguay's 17 departments. While 45% of TB cases among the Indigenous population occurred in the Chaco Region, in western Paraguay, notification among the Indigenous population was highest (1127.4 per 100,000) in the Capital, including the metropolitan area. Interpretation:TB cases are concentrated among Paraguay's incarcerated and Indigenous populations, both of which have extremely high relative risk of TB. Our findings highlight the urgency of expanding access to TB diagnosis, treatment, and prevention across the country and specifically, to the populations at heightened risk of TB. Funding:K01AI173385 (NIH, NIAID), University of Utah UROP.

RESUMEN Introducción: El personal de salud constituye un componente esencial de los sistemas sanitarios, pues facilita el acceso a la atención y se encuentra particularmente expuesto durante emergencias epidemiológicas. Desde la confirmación del primer caso de COVID‑19 en Paraguay, se implementaron diversas medidas para evitar la propagación del SARS‑CoV‑2, siendo el ambiente hospitalario un espacio crucial para prevenir la transmisión entre el personal de salud y los pacientes. En este contexto, el estudio tuvo como objetivo describir las características clínicas y epidemiológicas de la infección por SARS‑CoV‑2 en el personal de salud de Paraguay durante el periodo 2020‑2022. Materiales y métodos: Estudio observacional, de corte transversal, basado en datos provenientes de las notificaciones remitidas al Programa Nacional de Prevención, Vigilancia y Control de Infecciones hospitalarias. Se incluyeron los registros del personal de salud en servicio activo y se excluyeron aquellos con datos incompletos, personal no activo y casos descartados. Las variables cuantitativas se resumieron con medidas de tendencia central y dispersión. Al emplear datos anonimizados, no se vulneró la privacidad del personal. Resultados: Del total de casos confirmados, el 72,76% correspondió al sexo femenino, con una mediana de edad de 37 años. Se registraron 794 hospitalizaciones y 188 muertes. Las comorbilidades más frecuentes fueron obesidad, enfermedades pulmonares, diabetes y cardiopatías. La letalidad durante el periodo 2020 a 2022 fue del 0.52% en el personal de salud con resultado positivo a SARS-CoV-2. Conclusión: La infección por SARS‑CoV‑2 afectó principalmente a mujeres de 29 a 39 años, predominantemente del área de enfermería. Se registraron 36.015 casos, 794 hospitalizaciones y 188 defunciones, con una letalidad del 0,52%. Las comorbilidades más frecuentes fueron obesidad, cardiopatías crónicas y diabetes. La mayor concentración de casos se observó en las regiones sanitarias de Central y Capital, identificados como los principales focos de transmisión durante la pandemia.

Introduction:In Chile, the number of migrants affected by tuberculosis has experienced a significant increase from 7.1% in 2014 to 29.7% in 2023, ranking as the first group at risk. The objective was to estimate the time to diagnosis of tuberculosis from arrival in Chile in a series of migrants undergoing treatment between January 2021 and March 2022. Methods:We analyzed a cohort of migrants over 18 years of age with a diagnosis of tuberculosis treated in the communes of Recoleta and Independencia. Those who agreed to participate and signed the informed consent form were included. Cases with non-tuberculous mycobacteria and residents outside the Metropolitan Region were excluded. Sociodemographic, clinical, and arrival dates, as well as symptoms and diagnoses, were recorded. Proportional hazards models in STATA v.18 were used to analyze times according to independent variables. A p value < 0.05 was considered significant. Results:The median time to diagnosis was 93.5 months, varying by subgroup. The recent migration subgroup without Chilean documentation had a hazard ratio of 13.1, which indicates that, at any time after arrival, these individuals have a 13-fold increased risk of tuberculosis diagnosis compared to the reference subgroup (traditional migration with Chilean identity documents). This hazard ratio is reduced by 2.4 times when these types of migrants have documentation from Chile (95% confidence interval: 1.2 to 4.5). Conclusions:There is a wide range of time from arrival in Chile to the diagnosis of tuberculosis. Factors such as the type of migration and the type of identity document have an impact on the development of this disease. It is necessary to expedite the legal administrative process for migrants and implement timely screening policies, along with follow-up and improved access to healthcare, to reduce exposure and risk of tuberculosis.

IntroductionSnakebite envenoming (SBE) is a public health problem in Paraguay where the presence of 15 medically important snake species has been reported. Blessed with large forested areas, its economy largely relies on agricultural production which increases the exposure of outdoor workers to the morbidity and mortality of SBE. Lack of sufficient and accurate epidemiological data highlights the importance of drawing an updated picture of SBE burden in the country.MethodsWe performed a retrospective descriptive study on secondary SBE data reported to the national surveillance system between 2015 and 2021. We addressed the availability and quality of the data and assessed its epidemiological and sociodemographic burden in Paraguay over that time period.ResultsIn total, 1651 cases of SBE were reported between 2015 and 2021 representing an average of 235 cases per year (3.33 cases per 100 000 population). Overall, young males (68%, n=1125) of productive age (25 years old, IQR 29) in agricultural and/or livestock settings (47%, n=653) were the most affected population. Departments with a higher number of notifications were San Pedro (12%, n=191), Caazapá and Alto Paraná (10%, n=163). Regarding data quality, variables about clinical outcomes, treatment administration and case management were the worst reported.ConclusionSBE is a public health issue that affects young workers in rural areas in Paraguay. It mostly remains unattended and improvements in its reporting need to be done in order to gain a better insight into both the health and social burden of this neglected disease.

Background The increased risk of tuberculosis (TB) among people deprived of liberty (PDL) is due to individual and institution-level factors. We followed a cohort of PDL from 5 prisons in Paraguay to describe the risk of TB during incarceration and after they were released. Methods We linked a 2013 national census of prisons with TB records from the TB Program from 2010 to 2021 to identify TB notifications among incarcerated and formerly incarcerated individuals. We used multivariable Cox regression models to quantify the risk of TB during and following incarceration and to identify risk factors associated with TB. Findings Among 2996 individuals incarcerated, 451 (15.1%) were diagnosed with TB. Of these, 262 (58.1%) cases occurred during incarceration and 189 (41.9%) occurred in the community after release. In prison, the hazard ratio of developing TB was 1.97 (95% CI: 1.52-2.61) after six months of incarceration and increased to 2.78 (95% CI: 1.82-4.24) after 36 months compared with the first six months. The overall TB notification rate was 2940 per 100,000 person-years. This rate increased with the duration of incarceration from 1335 per 100,000 person-years in the first year to 8455 per 100,000 person-years after 8 years. Among former prisoners, the rate of TB decreased from 1717 in the first year after release to 593 per 100 000 person-years after 8 years of follow up. Interpretation Our study shows the alarming risk of TB associated with prison environments in Paraguay, and how this risk persists for years following incarceration. Effective TB control measures to protect the health of people during and following incarceration are urgently needed.

AbstractThere now exists a licensed chikungunya vaccine, however, it remains unclear if it could be deployed during outbreaks to reduce the health burden. We used an epidemic in Paraguay as a case study. We conducted a seroprevalence study and used models to reconstruct epidemic transmission dynamics, providing a framework to assess the theoretical impact of a vaccine had it been available. We estimated 33.0% (95% CI: 30.1-36.0) of the population became infected during the outbreak, 6.3% (95%CI: 5.8-6.9) of which were detected by the surveillance system, with a mean infection fatality ratio of 0.013 % (95%CI: 0.012-0.014). A disease-blocking vaccine with 75% efficacy deployed in 40% of > 12-year-olds over a three-month period would have prevented 34,200 (95% CI: 30,900-38,000) cases, representing 23% of cases, and 73 (95%CI: 66-81) deaths. If the vaccine also leads to infection blocking, 88% of cases would have been averted. These findings suggest the vaccine is an important new tool to control outbreaks.

While incidence of tuberculosis (TB) has decreased globally, in Paraguay, considered a medium-incidence country by the WHO, TB incidence has increased slightly from 42 per 100,000 in 2010 to 46 per 100,000 in 2022. We conducted a retrospective study of TB cases notified to the Paraguay National Program for Tuberculosis Control (NPTC) from 2018 to 2022 and quantified trends in specific populations identified as vulnerable. Of the 13,725 TB cases notified in Paraguay from 2018 to 2022, 2,331 (17%) occurred among incarcerated individuals and 1,743 (12.7%) occurred among self-identified Indigenous individuals. In 2022, the relative risk of TB was 87 and 6.4 among the incarcerated and Indigenous populations, compared with the non-incarcerated and non-Indigenous populations respectively. We found significant heterogeneity in TB incidence across Paraguay’s 17 departments. Our findings highlight the urgency of expanding access to TB diagnosis, treatment, and prevention in populations at heightened risk of TB in Paraguay.

Durante el verano del 2022 y 2023 ocurrió la mayor epidemia de Chikungunya en Paraguay, y una de las más grandes reportadas en la región. Estuvo centralizada en el área metropolitana de Asunción en una primera etapa, pero se expandió al resto del país durante los primeros meses del 2023. Este trabajo tiene el objetivo de describir epidemiológica y clínicamente la epidemia desde su inicio en la semana epidemiológica 40 del 2022 hasta la semana 20 del 2023. Metodología: es un estudio descriptivo que utiliza los datos públicos disponibles en la página de la Dirección General de Vigilancia de la Salud. Fueron confirmados 86.761 casos, 58% femenino, 8227 ingresos hospitalarios y 248 fallecidos. La letalidad global es de 2.8 por mil casos confirmados. Los grupos etarios más afectados corresponden a la franja de 0 a 4 años (9%), sin embargo, la mayor incidencia de casos se da en mayores de 80 años. Los principales desafíos de esta enfermedad son el abordaje multidisciplinario en la gestión del manejo del vector, la evaluación de las causas de esta alta letalidad y la necesidad de una vacuna de uso poblacional.

Dengue virus (DENV) has been a major public health concern in Paraguay, with frequent outbreaks occurring since early 1988. Although control measures have been implemented, dengue remains a significant health threat in the country, and continued efforts are required for prevention and control. In response to that, in collaboration with the Central Public Health Laboratory in Asunción, we conducted a portable whole-genome sequencing and phylodynamic analysis to investigate DENV viral strains circulating in Paraguay over the past epidemics. Our genomic surveillance activities revealed the co-circulation of multiple DENV serotypes: DENV-1 genotype V, the emerging DENV-2 genotype III, BR4-L2 clade, and DENV-4 genotype II. Results additionally highlight the possible role of Brazil as a source for the international dispersion of different viral strains to other countries in the Americas emphasizing the need for increased surveillance across the borders, for the early detection and response to outbreaks. This, in turn, emphasizes the critical role of genomic surveillance in monitoring and understanding arbovirus transmission and persistence locally and over long distances.

In this Policy Forum piece, Aditya Narayan and colleagues discuss the challenges and opportunities for tuberculosis preventive treatment in carceral settings.