Cost of intensive routine control and incremental cost of insecticide-treated curtain deployment in a setting with low Aedes aegypti infestation.

INTRODUCTION: Information regarding the cost of implementing insecticide-treated curtains (ITCs) is scarce. Therefore, we evaluated the ITC implementation cost, in addition to the costs of intensive conventional routine activities of the Aedes control program in the city of Guantanamo, Cuba. METHODS: A cost-analysis study was conducted from the perspective of the Aedes control program, nested in an ITC effectiveness trial, during 2009-2010. Data for this study were obtained from bookkeeping records and activity registers of the Provincial Aedes Control Programme Unit and the account records of the ITC trial. RESULTS: The annual cost of the routine Aedes control program activities was US$16.80 per household (p.h). Among 3,015 households, 6,714 ITCs were distributed. The total average cost per ITC distributed was US$3.42, and 74.3% of this cost was attributed to the cost of purchasing the ITCs. The annualized costs p.h. of ITC implementation was US$3.80. The additional annualized cost for deploying ITCs represented 19% and 48.4% of the total cost of the routine Aedes control and adult-stage Aedes control programs, respectively. The trial did not lead to further reductions in the already relatively low Aedes infestation levels. CONCLUSIONS: At current curtain prices, ITC deployment can hardly be considered an efficient option in Guantanamo and other comparable environments.

Cost of intensive routine control and incremental cost of insecticide-treated curtain deployment in a setting with low Aedes aegypti infestation

Abstract: INTRODUCTION Information regarding the cost of implementing insecticide-treated curtains (ITCs) is scarce. Therefore, we evaluated the ITC implementation cost, in addition to the costs of intensive conventional routine activities of the Aedes control program in the city of Guantanamo, Cuba. METHODS A cost-analysis study was conducted from the perspective of the Aedes control program, nested in an ITC effectiveness trial, during 2009-2010. Data for this study were obtained from bookkeeping records and activity registers of the Provincial Aedes Control Programme Unit and the account records of the ITC trial. RESULTS The annual cost of the routine Aedes control program activities was US$16.80 per household (p.h). Among 3,015 households, 6,714 ITCs were distributed. The total average cost per ITC distributed was US$3.42, and 74.3% of this cost was attributed to the cost of purchasing the ITCs. The annualized costs p.h. of ITC implementation was US$3.80. The additional annualized cost for deploying ITCs represented 19% and 48.4% of the total cost of the routine Aedes control and adult-stage Aedes control programs, respectively. The trial did not lead to further reductions in the already relatively low Aedes infestation levels. CONCLUSIONS At current curtain prices, ITC deployment can hardly be considered an efficient option in Guantanamo and other comparable environments.

Incremental cost of implementing residual insecticide treatment with delthametrine on top of intensive routine Aedes aegypti control.

OBJECTIVE: Information on the cost of implementing residual insecticide treatment (RIT) for Aedes control is scarce. We evaluated the incremental cost on top of intensive conventional routine activities of the Aedes control programme (ACP) in the city of Santiago de Cuba, Cuba. METHODS: We conducted the cost analysis study in 2011-2012, from the perspective of the ACP. Data sources were bookkeeping records, activity registers of the Provincial ACP Centre and the accounts of an RIT implementation study in 21 clusters of on average four house blocks comprising 5180 premises. RESULTS: The annual cost of the routine ACP activities was 19.66 US$ per household. RIT applications in rounds at 4-month intervals covering, on average, 97.2% and using 8.5 g of delthametrine annually per household, cost 3.06 US$ per household per year. Delthametrine comprised 66.5% of this cost; the additional cost for deploying RIT comprised 15.6% of the total ACP routine cost and 27% of the cost related to routine adult stage Aedes control. CONCLUSIONS: The incremental cost of implementing RIT is high. It should be weighed against the incremental effect on the burden caused by the array of pathogens transmitted by Aedes. The cost could be reduced if the insecticide became cheaper, by limiting the number of yearly applications or by targeting transmission hot spots.

No effect of insecticide treated curtain deployment on aedes infestation in a cluster randomized trial in a setting of low dengue transmission in Guantanamo, Cuba.

OBJECTIVE & METHODOLOGY: The current study evaluated the effectiveness and cost-effectiveness of Insecticide Treated Curtain (ITC) deployment for reducing dengue vector infestation levels in the Cuban context with intensive routine control activities. A cluster randomized controlled trial took place in Guantanamo city, east Cuba. Twelve neighborhoods (about 500 households each) were selected among the ones with the highest Aedes infestation levels in the previous two years, and were randomly allocated to the intervention and control arms. Long lasting ITC (PermaNet) were distributed in the intervention clusters in March 2009. Routine control activities were continued in the whole study area. In both study arms, we monitored monthly pre- and post-intervention House Index (HI, number of houses with at least 1 container with Aedes immature stages/100 houses inspected), during 12 and 18 months respectively. We evaluated the effect of ITC deployment on HI by fitting a generalized linear regression model with a negative binomial link function to these data. PRINCIPAL FINDINGS: At distribution, the ITC coverage (% of households using ≥1 ITC) reached 98.4%, with a median of 3 ITC distributed/household. After 18 months, the coverage remained 97.4%. The local Aedes species was susceptible to deltamethrin (mosquito mortality rate of 99.7%) and the residual deltamethrin activity in the ITC was within acceptable levels (mosquito mortality rate of 73.1%) after one year of curtain use. Over the 18 month observation period after ITC distribution, the adjusted HI rate ratio, intervention versus control clusters, was 1.15 (95% CI 0.57 to 2.34). The annualized cost per household of ITC implementation was 3.8 USD, against 16.8 USD for all routine ACP activities. CONCLUSION: Deployment of ITC in a setting with already intensive routine Aedes control actions does not lead to reductions in Aedes infestation levels.

Costs of dengue prevention and incremental cost of dengue outbreak control in Guantanamo, Cuba.

OBJECTIVE: To assess the economic cost of routine Aedes aegypti control in an at-risk environment without dengue endemicity and the incremental costs incurred during a sporadic outbreak. METHODS: The study was conducted in 2006 in the city of Guantanamo, Cuba. We took a societal perspective to calculate costs in months without dengue transmission (January-July) and during an outbreak (August-December). Data sources were bookkeeping records, direct observations and interviews. RESULTS: The total economic cost per inhabitant (p.i.) per month. (p.m.) increased from 2.76 USD in months without dengue transmission to 6.05 USD during an outbreak. In months without transmission, the routine Aedes control programme cost 1.67 USD p.i. p.m. Incremental costs during the outbreak were mainly incurred by the population and the primary/secondary level of the healthcare system, hardly by the vector control programme (1.64, 1.44 and 0.21 UDS increment p.i. p.m., respectively). The total cost for managing a hospitalized suspected dengue case was 296.60 USD (62.0% direct medical, 9.0% direct non-medical and 29.0% indirect costs). In both periods, the main cost drivers for the Aedes control programme, the healthcare system and the community were the value of personnel and volunteer time or productivity losses. CONCLUSIONS: Intensive efforts to keep A. aegypti infestation low entail important economic costs for society. When a dengue outbreak does occur eventually, costs increase sharply. In-depth studies should assess which mix of activities and actors could maximize the effectiveness and cost-effectiveness of routine Aedes control and dengue prevention.

Evidence on impact of community-based environmental management on dengue transmission in Santiago de Cuba

During the dengue outbreak that struck Santiago de Cuba in 2006–2007, we conducted anobservational study in the Mariana Grajales district, the former setting of a community trial for Aedes aegypti control. In the trial, community working groups (CWG) had been created in 29 randomly selected intervention house blocks, and routine vector control activities alone were conducted in the remaining 30 control blocks. The CWG elaborated and implemented with the population plans and activities to reduce Aedes infestation. They were still functional in 2006 and continued organizing community-based environmental management activities. The attack rate of dengue fever during the outbreak was 8.5 per 1000 inhabitants in the former intervention blocks and 38.1 per 1000 inhabitants in the control blocks, which corresponds to a relative risk of 4.5 (95 percent CI 3.1–6.5). There was a significantly higher proportion of unaffected intervention blocks, and affected blocks had on average substantially less cases than affected control blocks. This study indicates that community-based environmental management inserted in the routine A. aegypti control programme can not only sustainably curb vector infestation but also have an impact on dengue transmission(AU)

The cost of routine Aedes aegypti control and of insecticide-treated curtain implementation.

Insecticide-treated curtains (ITCs) are promoted for controlling the Dengue vector Aedes aegypti. We assessed the cost of the routine Aedes control program (RACP) and the cost of ITC implementation through the RACP and health committees in Venezuela and through health volunteers in Thailand. The yearly cost of the RACP per household amounted to US$2.14 and $1.89, respectively. The ITC implementation cost over three times more, depending on the channel used. In Venezuela the RACP was the most efficient implementation-channel. It spent US$1.90 (95% confidence interval [CI]: 1.83; 1.97) per curtain distributed, of which 76.9% for the curtain itself. Implementation by health committees cost significantly (P = 0.02) more: US$2.32 (95% CI: 1.93; 2.61) of which 63% for the curtain. For ITC implementation to be at least as cost-effective as the RACP, at equal effectiveness and actual ITC prices, the attained curtain coverage and the adulticiding effect should last for 3 years.

Evaluation of the effectiveness of insecticide treated materials for household level dengue vector control.

OBJECTIVE: To assess the operational effectiveness of long-lasting insecticide treated materials (ITMs), when used at household level, for the control of Aedes aegypti in moderately infested urban and suburban areas. METHODS: In an intervention study, ITMs consisting of curtains and water jar-covers (made from PermaNet) were distributed under routine field conditions in 10 clusters (5 urban and 5 suburban), with over 4000 houses, in Trujillo, Venezuela. Impact of the interventions were determined by comparing pre-and post-intervention measures of the Breteau index (BI, number of positive containers/100 houses) and pupae per person index (PPI), and by comparison with indices from untreated areas of the same municipalities. The effect of ITM coverage was modeled. RESULTS: At distribution, the proportion of households with ≥1 ITM curtain was 79.7% in urban and 75.2% in suburban clusters, but decreased to 32.3% and 39.0%, respectively, after 18 months. The corresponding figures for the proportion of jars using ITM covers were 34.0% and 50.8% at distribution and 17.0% and 21.0% after 18 months, respectively. Prior to intervention, the BI was 8.5 in urban clusters and 42.4 in suburban clusters, and the PPI was 0.2 and 0.9, respectively. In both urban and suburban clusters, the BI showed a sustained 55% decrease, while no discernable pattern was observed at the municipal level. After controlling for confounding factors, the percentage ITM curtain coverage, but not ITM jar-cover coverage, was significantly associated with both entomological indices (Incidence Rate Ratio = 0.98; 95%CI 0.97-0.99). The IRR implied that ITM curtain coverage of at least 50% was necessary to reduce A. aegypti infestation levels by 50%. CONCLUSION: Deployment of insecticide treated window curtains in households can result in significant reductions in A. aegypti levels when dengue vector infestations are moderate, but the magnitude of the effect depends on the coverage attained, which itself can decline rapidly over time.

Evidence on impact of community-based environmental management on dengue transmission in Santiago de Cuba.

During the dengue outbreak that struck Santiago de Cuba in 2006-2007, we conducted an observational study in the Mariana Grajales district, the former setting of a community trial for Aedes aegypti control. In the trial, community working groups (CWG) had been created in 29 randomly selected intervention house blocks, and routine vector control activities alone were conducted in the remaining 30 control blocks. The CWG elaborated and implemented with the population plans and activities to reduce Aedes infestation. They were still functional in 2006 and continued organizing community-based environmental management activities. The attack rate of dengue fever during the outbreak was 8.5 per 1000 inhabitants in the former intervention blocks and 38.1 per 1000 inhabitants in the control blocks, which corresponds to a relative risk of 4.5 (95% CI 3.1-6.5). There was a significantly higher proportion of unaffected intervention blocks, and affected blocks had on average substantially less cases than affected control blocks. This study indicates that community-based environmental management inserted in the routine A. aegypti control programme can not only sustainably curb vector infestation but also have an impact on dengue transmission.

Cost-effectiveness of a community-based approach intertwined with a vertical Aedes control program.

We compared in a 5-year intervention study the cost-effectiveness of community-based environmental management intertwined with routine vertical Aedes control and of routine vertical control only. At baseline (year 2000), Aedes infestation levels and economic costs for vector control were comparable in intervention and control areas (house index, 2.23% versus 2.21% and US$21 versus US$24/yr/inhabitant, respectively). By 2004, house indices became 0.22% versus 2.36% and the costs were 29.8 US$ versus 36.7 US$/yr/inhabitant, respectively. The community cost made up 38.6% of the total economic cost in 2004 in the intervention areas against 23.5% in 2000. The average cost-effectiveness ratio for the intervention period 2001-2004, expressed as the societal cost incurred for the reduction (from baseline) of Aedes foci, was US$831.1 per focus in the intervention areas versus US$2,465.6 in the control areas. The intervention produced economic savings and health benefits that were sustained over the whole observation period.

The unbearable lightness of technocratic efforts at dengue control.

OBJECTIVE: To identify key elements that should provide an added value and assure sustainable effects of the deployment of technical tools for Aedes aegypti control. METHODS: An observational study was conducted between April 2001 and March 2002 in 30 blocks (1574 houses) in the central zone of Guantanamo city. A trial that combined two complementary technical interventions, the distribution of new ground level water tanks and the intensive use of insecticide, was nested in May 2001. Another 30 blocks (1535 houses) were selected as control area. We assessed community perceptions and household risk behaviour at baseline and after 9 months, and measured the trial's impact through entomological indices. RESULTS: Perceived self efficacy to solve A. aegypti infestation and prevent dengue was not modified. We found no changes in behaviour. In the study area the container indices decreased significantly from 0.7% before to 0.1% 1 month after the intervention. Six months later, they had increased to 2.7% and uncovered new water tanks constituted 75.9% of all breeding sites. Over the 9 months after the trial the average monthly house indices were similar in the study and control areas. A technical approach and lack of community involvement in the trial's implementation were the main causes of these short-lived results. CONCLUSIONS: Top-down deployment of technical tools without active involvement of the community has a temporary effect and does not lead to the behavioural changes necessary for sustainable A. aegypti control.

Phase I clinical evaluation of a synthetic oligosaccharide-protein conjugate vaccine against Haemophilus influenzae type b in human adult volunteers.

Since 1989, we have been involved in the development of a vaccine against Haemophilus influenzae type b. The new vaccine is based on the conjugation of synthetic oligosaccharides to tetanus toxoid. Our main goals have been (i) to verify the feasibility of using the synthetic antigen and (ii) to search for new production alternatives for this important infant vaccine. Overall, eight trials have already been conducted with adults, children (4 to 5 years old), and infants. We have described herein the details from the first two phase I clinical trials conducted with human adult volunteers under double blind, randomized conditions. The participants each received a single intramuscular injection to evaluate safety and initial immunogenicity. We have found an excellent safety profile and an antibody response similar to the one observed for the control vaccine.

Phase I Clinical Evaluation of a Synthetic Oligosaccharide-Protein Conjugate Vaccine against Haemophilus influenzae Type b in Human Adult Volunteers

Since 1989, we have been involved in the development of a vaccine against Haemophilus influenzae type b. The new vaccine is based on the conjugation of synthetic oligosaccharides to tetanus toxoid. Our main goals have been (i) to verify the feasibility of using the synthetic antigen and (ii) to search for new production alternatives for this important infant vaccine. Overall, eight trials have already been conducted with adults, children (4 to 5 years old), and infants. We have described herein the details from the first two phase I clinical trials conducted with human adult volunteers under double blind, randomized conditions. The participants each received a single intramuscular injection to evaluate safety and initial immunogenicity. We have found an excellent safety profile and an antibody response similar to the one observed for the control vaccine(AU)

Desde 1989, hemos participado en el desarrollo de una vacuna contra el Haemophilus influenzae tipo b. La nueva vacuna se basa en la conjugación de oligosacáridos sintéticos a toxoide tetánico. Nuestros principales objetivos han sido (i) para verificar la viabilidad de la utilización de la síntesis de antígenos y (ii) búsqueda de nuevas alternativas de producción para este importante vacuna infantil. En total, ocho ensayos ya se han realizado con adultos, niños (de 4 a 5 años), y los lactantes. Hemos descrito en este documento los detalles de los dos primeros ensayos clínicos de fase I realizado con voluntarios adultos humanos en virtud de doble ciego, randomizado condiciones. Los participantes recibieron una única inyección intramuscular para evaluar la seguridad y la inmunogenicidad inicial. Hemos encontrado un excelente perfil de seguridad y una respuesta de anticuerpos similar a la observada para el control de vacunas

Validación de un ensayo tipo ELISA para la cuantificación de anticuerpos contra el polisacárido capsular de Haemophilus influenzae tipo b / Validation of an ELISA assay for the quantification of antibodies against Haemophilus influenzae type b capsular polysaccharide

Se llevó a cabo el estudio de validación de un ensayo tipo ELISA —aceptado internacionalmente para este propósito—, con el objetivo de disponer de un método para la cuantificación de anticuerpos contra el polisacárido capsular de Haemophilus influenzae tipo b (Hib), en los ensayos clínicos previstos para demostrar la inmunogenicidad de una nueva vacuna conjugada, compuesta por un antígeno sintético. La validación fue conducida en el Laboratorio Nacional de Referencia para Haemophilus, en el Instituto de Medicina Tropical “Pedro Kourí”, La Habana, Cuba, y se diseñó para ello un protocolo en el cual se consideró la determinación de la precisión, exactitud, linealidad y límite de detección del ensayo. En la preparación de la curva patrón estándar se empleó el suero de referencia internacional Hib Lote 1983. Para la repetibilidad y reproducibilidad del sistema se observaron índices de dispersión inferiores a 10 y 20 por ciento, respectivamente. El límite de detección fue de 3,6 ng/m, y los ensayos de recuperación y linealidad revelaron la alta exactitud del método. Se concluyó que durante la evaluación clínica del candidato a vacuna, obtenido por síntesis química, la cuantificación de anticuerpos contra el polisacárido capsular de Hib podía ser afrontada con apropiada precisión y exactitud mediante el método propuesto

Validación de un ensayo tipo ELISA para la cuantificación de anticuerpos contra el polisacárido capsular de Haemophilus influenzae tipo b / Validation of an ELISA assay for the quantification of antibodies against Haemophilus influenzae type b capsular polysaccharide

Se llevó a cabo el estudio de validación de un ensayo tipo ELISA —aceptado internacionalmente para este propósito—, con el objetivo de disponer de un método para la cuantificación de anticuerpos contra el polisacárido capsular de Haemophilus influenzae tipo b (Hib), en los ensayos clínicos previstos para demostrar la inmunogenicidad de una nueva vacuna conjugada, compuesta por un antígeno sintético. La validación fue conducida en el Laboratorio Nacional de Referencia para Haemophilus, en el Instituto de Medicina Tropical “Pedro Kourí”, La Habana, Cuba, y se diseñó para ello un protocolo en el cual se consideró la determinación de la precisión, exactitud, linealidad y límite de detección del ensayo. En la preparación de la curva patrón estándar se empleó el suero de referencia internacional Hib Lote 1983. Para la repetibilidad y reproducibilidad del sistema se observaron índices de dispersión inferiores a 10 y 20 por ciento, respectivamente. El límite de detección fue de 3,6 ng/m, y los ensayos de recuperación y linealidad revelaron la alta exactitud del método. Se concluyó que durante la evaluación clínica del candidato a vacuna, obtenido por síntesis química, la cuantificación de anticuerpos contra el polisacárido capsular de Hib podía ser afrontada con apropiada precisión y exactitud mediante el método propuesto(AU)

[Validation of an ELISA assay for the quantification of antibodies against Haemophilus influenzae type b capsular polysaccharide]. / Validación de un ensayo tipo ELISA para la cuantificación de anticuerpos contra el polisacárido capsular de Haemophilus influenzae tipo b.

The validation study of an ELISA assay -internationally accepted for this purpose- was conducted aimed at having a method for the quantification of antibodies against Haemophilus influenzae type b (Hib) capsular polysaccharide in the clinical trials used to prove the immunogenicity of a new conjugated vaccine composed of a synthetic antigen. The validation was carried out in the National Haemophilus Reference Laboratory, in "Pedro Kouri" Institute of Tropical Medicine, Havana, Cuba. A protocol was designed, in which the determination of accuracy, exactness, linearity and limit of the detection of the assay were considered. The Hib Batch 1983 international reference serum was used in the preparation of the standard pattern curve. Dispersion indexes lower than 10 and 20% were observed for the repeatability and reproducibility of the system, respectively. The limit of detection was 3.6 ng/m and the recovery and linearity trials showed the high accuracy of the method. It was concluded that during the clinical evaluation of the candidate vaccine obtained by chemical synthesis, the quantification of antibodies against Hib capsular polysaccharide may be faced with an appropriate precision and exactness by using the proposed method.

A synthetic conjugate polysaccharide vaccine against Haemophilus influenzae type b.

Glycoconjugate vaccines provide effective prophylaxis against bacterial infections. To date, however, no commercial vaccine has been available in which the key carbohydrate antigens are produced synthetically. We describe the large-scale synthesis, pharmaceutical development, and clinical evaluation of a conjugate vaccine composed of a synthetic capsular polysaccharide antigen of Haemophilus influenzae type b (Hib). The vaccine was evaluated in clinical trials in Cuba and showed long-term protective antibody titers that compared favorably to licensed products prepared with the Hib polysaccharide extracted from bacteria. This demonstrates that access to synthetic complex carbohydrate-based vaccines is feasible and provides a basis for further development of similar approaches for other human pathogens.

Reactogenicidad de la vacuna cubana trivalente contra la / leptospirosis humana en un ensayo clínico de fase II / Reactogenicity of the first Trivalent Cuban Human Leptospirosis Vaccine in Phase II Clinical

Con el objetivo de evaluar la reactogenicidad de la vacuna cubana trivalente contra la leptospirosis humana (vax- SPIRAL) en grupos de voluntarios sanos utilizando diferentes dosis, se realizó un ensayo clínico controlado,aleatorio y a doble ciego. Los voluntarios fueron distribuidos en dos grupos (vacunados y placebos) para evaluar las reacciones adversas en diferentes concentraciones de dosis (0,25 y 0,5 mL). Los síntomas y signos locales evaluados fueron: dolor, rubor, infiltración local, prurito, necrosis y absceso, y generales: fiebre, febrícula, cefalea, lipotimia, náuseas, vómitos, rash y malestar general. No se presentaron eventos adversos serios tras la administración de la vacuna. La febrícula, el dolor local en el sitio de inyección y el malestar general fueron los signos y síntomas más frecuentes reportados en mayor proporción en los vacunados con dosis de 0,5 mL. La mayoría desaparecieron a las 72 horas. Los resultados del estudio demostraron que vax-SPIRAL es una vacuna segura y poco reactogénica para adultos humanos en las edades comprendidas en los ensayos clínicos realizados(AU)

Impacto económico-social del Programa Nacional de Control de la Tuberculosis (PNCT) en la población cubana / Economic and social impact of the National Tuberculosis Control Program (NTCP) on the Cuban population

Las estrategias de control de la tuberculosis (TB) poseen un costo/efectividad muy favorable. Se describen y valoran los impactos del programa de control, utilizando las series temporales de casos nuevos y fallecidos notificados por TB en 1964-91 y 1992-96. Se estimaron los casos evitados y años potenciales de vida ganados; gastos por quimioterapia, hospitalizaciones y prestaciones sociales ahorrados, valorados sobre la base del número de casos nuevos, definiciones y casos esperados estimados. Entre 1965-1991, la incidencia estimada de TB se redujo en 94,6 por ciento (4 por ciento por año), se evitaron unos 86.500 casos nuevos; hubo una ganancia potencial de 166.439 años de vida. Se estimó un ahorro de 2.831.625,3 pesos solo por costo de tuberculostáticos dejados de aplicar. Se redujeron los pagos por subsidio salarial de trabajadores enfermos por TB con 82 millones de pesos ahorrados. El total ahorrado estimado asciende a 494.919.631,3 pesos. Estos impactos son muy importantes y avalan la efectividad de las estrategias aplicadas bajo las circunstancias sociopolíticas del país, favoreciendo los enfoques para un programa de eliminación(AU)

Impacto económico-social del Programa Nacional de Control de la Tuberculosis (PNCT) en la población cubana / Economic and social impact of the National Tuberculosis Control Program (NTCP) on the Cuban population

Las estrategias de control de la tuberculosis (TB) poseen un costo/efectividad muy favorable. Se describen y valoran los impactos del programa de control, utilizando las series temporales de casos nuevos y fallecidos notificados por TB en 1964-91 y 1992-96. Se estimaron los casos evitados y años potenciales de vida ganados; gastos por quimioterapia, hospitalizaciones y prestaciones sociales ahorrados, valorados sobre la base del número de casos nuevos, definiciones y casos esperados estimados. Entre 1965-1991, la incidencia estimada de TB se redujo en 94,6 por ciento (4 por ciento por año), se evitaron unos 86.500 casos nuevos; hubo una ganancia potencial de 166.439 años de vida. Se estimó un ahorro de 2.831.625,3 pesos solo por costo de tuberculostáticos dejados de aplicar. Se redujeron los pagos por subsidio salarial de trabajadores enfermos por TB con 82 millones de pesos ahorrados. El total ahorrado estimado asciende a 494.919.631,3 pesos. Estos impactos son muy importantes y avalan la efectividad de las estrategias aplicadas bajo las circunstancias sociopolíticas del país, favoreciendo los enfoques para un programa de eliminación.