The estimated treatment gap for Trypanosoma cruzi infection in Colombia fell markedly over the decade, but it remained nearly half of the modeled need at the end of the period. Under the study’s main scenario, the gap dropped from 77.5% in 2012 to 48.1% in 2022, a 38% reduction overall. The gap is the share of people judged to need treatment who did not receive it through health services.
The finding comes from a descriptive cross-sectional study using secondary official data. Researchers examined confirmed infections and recorded antiparasitic treatment initiations between 2012 and 2022 to track how the gap changed over time and across departments.
To estimate who had an indication for treatment, the researchers used two assumptions. Scenario A treated 70% of confirmed infections as treatment-indicated, while Scenario B used 85%. In each case, the estimated number eligible for treatment was compared with the number recorded as starting treatment to calculate the gap.
Across the period, the records listed 4,920 confirmed cases and 1,781 treatment initiations. On average, notifications fell 0.9% a year, while treatment initiation rose 8.7% a year. The annual averages were 492 confirmed cases and 178 treatment initiations.
The gap did not fall steadily
The national estimate did not fall in a straight line. Under Scenario A, it rose 4.5% from 2012 to 2014, reaching 81%, before falling 40.7% from 2014 to 2022. That left the 2022 estimate 38% below its 2012 level.
A Joinpoint analysis, which looks for changes in the direction of a trend, estimated an annual percentage change of 2.72% for the 2012 to 2014 increase and 7.17% for the 2014 to 2022 decrease. The later trend was statistically significant at p < 0.05, while the early segment was not reported as statistically significant.
The choice of treatment assumption changed the forecast. From 2012 to 2022, Scenario B showed a 30.3% reduction in the gap, smaller than Scenario A’s 38% reduction. A simple linear projection through 2030 put the gap at 27.7% under Scenario B and 13.4% under Scenario A, corresponding to modeled reductions of 66% and 82.7%, respectively, from 2012. These are projections based on continuing the observed pattern, not observed future outcomes.
A national average with gaps in the data
The national figures also conceal how uneven the underlying records were. The gap could be estimated for only 9 of Colombia’s 32 departments, or 28.1%. Nineteen departments, 59.4% of the total, had no treatment-initiation information, while four departments, 12.5%, recorded more treatment initiations than cases. Departmental patterns were heterogeneous.
The result means the national estimate cannot be read as a representative department-by-department picture of Colombia. Most departments did not have the complete information needed for a comparable estimate.
Case counts came from SIVIGILA annual reports, while treatment initiations came from the National Chagas Subprogram database. The 2020 data were excluded because reporting on access to diagnosis and treatment was interrupted during the SARS-CoV-2 pandemic.
Data for 2021 and 2022 may still reflect health-system disruption, so trends from 2019 to 2022 should be interpreted cautiously. The missing year and possible disruption at the end of the series make the apparent decline harder to read as a continuous trend.
The study also did not assess diagnostic coverage or the diagnostic gap among people at risk. The authors note that coverage still had limitations even after a new diagnostic algorithm was implemented in 2017. As a result, the treatment-gap estimates describe people who appeared in confirmed-case records, not the full population at risk.
Taken together, the results point to a substantial fall in the modeled gap while leaving open what accounts for the remaining shortfall. Because the study describes patterns in existing records, it cannot show that a particular roadmap, policy or intervention caused the decline.
Paper data and sources
Original title: Analysis of the therapeutic gap for Trypanosoma cruzi infection in Colombia (2012 - 2022)
Authors: Herazo R, Caicedo Díaz R, Vera Soto M et al.
Journal/Repository: Memorias do Instituto Oswaldo Cruz
Status: Peer-reviewed
First online: 2026-10-19
DOI: Not available
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