Caracterización y evolución temporal de la mortalidad por zoonosis bajo declaración obligatoria, entre los años 1997 y 2018 / Characterization and temporal evolution of mortality due to zoonoses under mandatory declaration, between the years 1997 and 2018

INTRODUCCIÓN: Las zoonosis son enfermedades transmitidas desde un hospedador animal al ser humano o viceversa. En Chile, las zoonosis de Notificación Obligatoria (NO) son: brucelosis, carbunco, triquinosis, hidatidosis, leptospirosis, dengue, enfermedad de Chagas, hantavirosis y rabia. OBJETIVO: Evaluar la tendencia y caracterizar la mortalidad por zoonosis de NO en Chile entre 1997-2018. METODOLOGÍA: Estudio ecológico de la mortalidad por zoonosis de NO. Se utilizaron bases de mortalidad y población oficiales. Se describió la mortalidad relativa, general y específica, según variables sociodemográficas. Se calcularon tasas de mortalidad anuales brutas (TMb) y ajustadas (TMa, método directo). Se evaluó la tendencia temporal con modelos de regresión de Prais-Winsten. Resultados: Entre 1997 y 2018 la mortalidad por zoonosis de NO correspondió al 0,12% (2.359 muertes) de la mortalidad total, siendo las principales causas la enfermedad de Chagas (59,8%), hidatidosis (23,9%) y hantavirosis (13,8%). La TMa general disminuyó significativamente (B: -0,017; IC95%: -0,024; -0,009) al igual que hidatidosis (B: -0,011; IC95%: -0,013; -0,008), sólo hantavirosis mostró un aumento (no significativo). CONCLUSIÓN: La mortalidad por zoonosis de NO disminuyó durante el período estudiado; solo la hantavirosis mostró un aumento en su tendencia. Se sugiere enfocar estrategias para prevenir la transmisibilidad y mortalidad por hanta, así como mejorar el acceso a tratamiento para las otras zoonosis.

BACKGROUND: Zoonoses are diseases transmitted from an animal host to humans or vice versa. In Chile, the zoonoses of mandatory notification are brucellosis, anthrax, trichinosis, hydatidosis, leptospirosis, dengue, Chagas disease, hantavirosis and rabies. AIM: To assess the trend and characterize the mortality from zoonoses of mandatory notification in Chile between 1997-2018. METHODS: An official mortality and population data were used. Relative, general and specific mortality rates were described according to sociodemographic variables. Crude and adjusted annual mortality rates (direct method) were calculated. Temporal trend was evaluated with the Prais-Winsten regression model. RESULTS: Between 1997 and 2018, the mortality rate due to zoonosis of mandatory notification corresponded to 0.13% (2152 deaths) of the total mortality, being Chagas disease (59.2%), hydatidosis (24.6%) and hantavirosis (13.5%) the main causes. The general adjusted mortality rate decreased significantly (B: -0.017; IC95%: -0.024; -0.009) as did hydatidosis (B: -0.011; IC95%: -0.013; -0.008), and only hantavirosis showed an increase trend (not significant). CONCLUSION: Mortality due to zoonoses decreased during the period; only hantavirosis showed an increasing trend. It is suggested to focus on strategies to prevent contagion and mortality by hantavirosis, as well as to improve access to treatment for the other zoonoses.

Contribution of Anthropogenic Factors and Climate Variables to Human Cystic Echinococcosis Mortality in Chile (2001-2011).

Here we assess the effect of weather and anthropogenic environmental variables, particularly urbanization, on cystic echinococcosis mortality in Chile from 2001 to 2011 using a nonparametric regression model, multivariate adaptive regression splines, and Poisson nonlinear regression models. This study integrated data from various sources on weather and anthropogenic variables. The canine population had the greatest influence on human cystic echinococcosis mortality during the period analyzed. Urbanization among anthropogenic variables and temperature and precipitation among the weather-related variables were the main factors related to cystic echinococcosis deaths. Deaths decreased with urbanization level. Temperature showed a nonlinear impact on mortality, with an optimum value ∼11°C. Public policies aimed at improving safe management of companion animal populations are crucial in controlling the spread of this disease. Effective animal management strategies would have wide-ranging public health benefits, advance the welfare of companion animals and livestock, and decrease the number of human cystic echinococcosis cases.

[Epidemiological description of human and animal hydatidosis in Los Ríos region, 1999- 2009]. / Caracterización epidemiológica de hidatidosis humana y animal en la Región de Los Ríos, 1999-2009.

OBJECTIVE: To determine the prevalence of hydatidosis in humans and livestock in the Los Ríos region during the years 1999-2009. METHODS: A retrospective survey of all discharge records of patients undergoing removal of cysts produced by Echinococcus granulosus during the period 1999-2009 in the Hospital Clinico Regional of Valdivia was conducted. With the information provided incidence rate, mortality rate and fatality rate were calculated. Additionally, with the aim of determining prevalence of hydatidosis in livestock (i.e. cattle, sheep and pigs) official records of slaughtered animals for the same period from the Ministry of Health of Los Ríos region were searched. RESULTS: During the ten-year period 238 new human cases were recorded, the average incidence rate for the period was 6.1 per 100,000 inhabitants, the mortality rate was 0.1 per 100,000 inhabitants, and the fatality rate was 1.3%. The most affected class group was the 15-64 years old with a 70% of cases. The districts more affected were Valdivia and Río Bueno. Most cases (54%) were from patients from rural areas, while the occupation more affected was housekeeping (29%). The liver (56%) and lungs (33%) were the localization where cysts were most frequently found. On 55% of cases, patients did not show any complication; meanwhile, infected cyst (11%) and unspecified complicated (8%) were the more frequent complication. Overall, 89% of cases recovered totally after surgery. Finally, the average in patient time was 14.7 bed-days. Prevalence of hydatidosis in livestock was 23% in cattle, 23% in sheep and 12% in pigs. The highest prevalence was found in slaughter houses in the districts of Panguipulli and San José de la Mariquina. DISCUSSION: Human and animal hydatidosis is highly prevalent in humans and livestock in Los Ríos region compared to national and international records. Further research is recommended to assess risk factors for human infection and improving record-keeping and trazability of slaughtered animals to implement control measures at the farm level to help to stop the life cycle of the parasite and thus reduce human infections.

Caracterización epidemiológica de hidatidosis humana y animal en la Región de Los Ríos, 1999-2009 / Epidemiological description of human and animal hydatidosis in Los Ríos region, 1999- 2009

Objective: To determine the prevalence of hydatidosis in humans and livestock in the Los Ríos region during the years 1999-2009. Methods: A retrospective survey of all discharge records of patients undergoing removal of cysts produced by Echinococcus granulosus during the period 1999-2009 in the Hospital Clinico Regional of Valdivia was conducted. With the information provided incidence rate, mortality rate and fatality rate were calculated. Additionally, with the aim of determining prevalence of hydatidosis in livestock (i.e. cattle, sheep and pigs) official records of slaughtered animals for the same period from the Ministry of Health of Los Ríos region were searched. Results: During the ten-year period 238 new human cases were recorded, the average incidence rate for the period was 6.1 per 100,000 inhabitants, the mortality rate was 0.1 per 100,000 inhabitants, and the fatality rate was 1.3%. The most affected class group was the 15-64 years old with a 70% of cases. The districts more affected were Valdivia and Río Bueno. Most cases (54%) were from patients from rural areas, while the occupation more affected was housekeeping (29%). The liver (56%) and lungs (33%) were the localization where cysts were most frequently found. On 55% of cases, patients did not show any complication; meanwhile, infected cyst (11%) and unspecified complicated (8%) were the more frequent complication. Overall, 89% of cases recovered totally after surgery. Finally, the average in patient time was 14.7 bed-days. Prevalence of hydatidosis in livestock was 23% in cattle, 23% in sheep and 12% in pigs. The highest prevalence was found in slaughter houses in the districts of Panguipulli and San José de la Mariquina. Discussion: Human and animal hydatidosis is highly prevalent in humans and livestock in Los Ríos region compared to national and international records. Further research is recommended to assess risk factors for human infection and improving record-keeping and trazability of slaughtered animals to implement control measures at the farm level to help to stop the life cycle of the parasite and thus reduce human infections.

Objetivos y Métodos: Para determinar la prevalencia de hidatidosis humana y animal en la Región de Los Ríos durante los años 1999-2009, se realizó un análisis retrospectivo de las fichas clínicas de operados por esta enfermedad en el Hospital Clínico Regional de Valdivia. Se cuantificó morbilidad, mortalidad y letalidad y se determinaron algunas características epidemiológicas de la enfermedad. Adicionalmente, para determinar la prevalencia de equinococosis quística en el ganado, se analizaron los registros oficiales sobre la frecuencia de presentación de quistes en vísceras decomisadas en bovinos, ovinos y porcinos faenados en mataderos de la región durante el mismo período, obtenidos de la SEREMI de Salud. Resultados: Se registraron 238 casos nuevos en humanos con una tasa de incidencia promedio de 6,1 por 100 mil habs., una tasa de mortalidad de 0,1 por 100 mil habs. y una tasa de letalidad de 1,3%. En total, 53% de los casos fueron hombres y 47% mujeres. El grupo de edad entre 15 y 64 años fue el más afectado (70% del total). Las comunas con mayor número de casos fueron Valdivia y Río Bueno. Se detectaron más casos (54%) en zonas rurales que urbanas (46%). Por otro lado, la ocupación más afectada correspondió a dueñas de casa. La localización más frecuente fue hepática exclusiva (56%). Un 55% de los pacientes no mostró complicación de los quistes tratados. Después de la operación, 89% de los casos se recuperó totalmente, mientras que el período de hospitalización promedio fue de 14,7 días-cama por paciente. La prevalencia de equinococosis en ganado fue de 23% en bovinos, 23% en ovinos y 12% en porcinos. Las mayores prevalencias se reportaron en mataderos de Panguipulli y San José de la Mariquina. Discusión: La hidatidosis humana y animal son altamente prevalentes en la Región de Los Ríos comparadas con el resto del país y otras naciones. Se recomienda la realización de estudios avanzados para determinar factores de riesgo para la infección en humanos y realizar mejoras en la trazabilidad de los animales sacrificados para implementar medidas de control a nivel del predio y de esa forma cortar el ciclo del parásito y ayudar a reducir la infección en humanos.

[Human hydatidosis in children: manifestation of failure in the control and prevention measures. Chile, 2001-2011]. / Hidatidosis humana en menores de edad: manifestación de fracaso en las medidas de control y prevención. Chile, 2001-2011.

BACKGROUND: Hydatidosis is mainly a slowly developing disease, so its appearance in children and adolescents means a relatively recent acquisition; its quantification at this age groups is an indirect mechanism for the evaluation of a prevention and control program. OBJECTIVE: To characterize human hydatidosis in children aged 0 to 18 years in Chile. MATERIAL: Data from the Disease Notification System (2001-2009), hospital discharges (2001-2008), Deaths (2001-2008) and Years of Potential Life Lost (2001-2008) were used. RESULTS: The incidence rate for the period was 4.4 cases per 100.000 inhabitants, male dominated. Hospital discharges rate for the period was 40.3 discharges per 100.000 inhabitants. The mortality rate for the period was 0.13 deaths per 100 000 inhabitants. CONCLUSIONS: The incidence rates of cases reported, hospital discharges and mortality tend to decrease. However, each new infection reflects the failure of prevention and control, which suggested to incorporate surveillance system tracking and monitoring of cases particularly children's domiciled contacts.

Hidatidosis humana en menores de edad: manifestación de fracaso en las medidas de control y prevención. Chile, 2001-2011 / Human hydatidosis in children: manifestation of failure in the control and prevention measures. Chile, 2001-2011

Background: Hydatidosis is mainly a slowly developing disease, so its appearance in children and adolescents means a relatively recent acquisition; its quantification at this age groups is an indirect mechanism for the evaluation of a prevention and control program. Objective: To characterize human hydatidosis in children aged 0 to 18 years in Chile. Material: Data from the Disease Notification System (2001-2009), hospital discharges (2001-2008), Deaths (2001-2008) and Years of Potential Life Lost (2001-2008) were used. Results: The incidence rate for the period was 4.4 cases per 100.000 inhabitants, male dominated. Hospital discharges rate for the period was 40.3 discharges per 100.000 inhabitants. The mortality rate for the period was 0.13 deaths per 100 000 inhabitants. Conclusions: The incidence rates of cases reported, hospital discharges and mortality tend to decrease. However, each new infection reflects the failure of prevention and control, which suggested to incorporate surveillance system tracking and monitoring of cases particularly children's domiciled contacts.

Introducción: La hidatidosis es mayoritariamente una afección de desarrollo lento y, por lo tanto, infecciones en la infancia y adolescencia traducen infecciones relativamente recientes; su cuantificación a estas edades es, indirectamente, un mecanismo de evaluación del sistema de prevención y control de la misma. Objetivo: Caracterizar epidemiológicamente la hidatidosis humana en pacientes entre 0 y 18 años de edad en Chile. Material: Se utilizaron datos del Sistema de Notificación Obligatoria (2001-2011), Egresos Hospitalarios (2001-2011), Defunciones (2001-2011) y Años de Vida Potencialmente Perdidos (2001-2011). Resultados: La tasa de incidencia para el período fue 4,4 casos por 100 mil habts., con predominio masculino. La tasa de egresos hospitalarios para el período fue 40,3 egresos por 100 mil habts. La tasa de mortalidad para el período fue de 0,13 defunciones por 100 mil habts. Conclusiones: Las tasas de incidencia de casos notificados, egresos hospitalarios y mortalidad tienden a disminuir. Sin embargo, cada nueva infección refleja el fracaso de las medidas de prevención y control. Se sugiere incorporar al sistema de vigilancia un seguimiento y monitoreo de casos contactos particularmente de menores de edad que compartan domicilio.

[Characterization of human hydatidosis mortality: Chile, 2000-2010]. / Caracterización de la mortalidad por hidatidosis humana: Chile, 2000-2010.

BACKGROUND: Hydatidosis as a worldwide zoonosis with a high socio-economic impact in Chile and other countries for which it is a notifiable human disease in our country. OBJECTIVE: To characterize death rates by hydatidosis and whether there are differences according to the region of residence. MATERIAL: A descriptive analysis using Data System Deaths (2000-2010) was performed. RESULTS: The total number of deaths was 293 (56% male). The mortality rate changed from 0.16 in 2000 to 0.11 in 2010 per 100.000 inhabitants. The main diagnosis corresponded to B67.9 (Echinococcosis, other and unspecified). Most fatal cases had a basic level of education and the Araucanía Region had the highest mortality rate. There was a loss of life of 5022.04 years by the premature death of 293 people, with a ratio of 0.31 PYLL years lost per 1000 inhabitants. In the Araucanía Region this ratio increased to 1.03 PYLL years lost per 1000 inhabitants. CONCLUSIONS: The mortality rate tends to decrease, however this trend might mask regional differences. It should be noted that deaths caused by hydatidosis are preventable deaths and therefore unjust. Finally, the mortality analysis is important to better understand the burden of the disease and evaluate the effectiveness of public health interventions.

Caracterización de la mortalidad por hidatidosis humana: Chile, 2000-2010 / Characterization of human hydatidosis mortality: Chile, 2000-2010

Background: Hydatidosis as a worldwide zoonosis with a high socio-economic impact in Chile and other countries for which it is a notifiable human disease in our country. Objective: To characterize death rates by hydatidosis and whether there are differences according to the region of residence. Material: A descriptive analysis using Data System Deaths (2000-2010) was performed. Results: The total number of deaths was 293 (56% male). The mortality rate changed from 0.16 in 2000 to 0.11 in 2010 per 100.000 inhabitants. The main diagnosis corresponded to B67.9 (Echinococcosis, other and unspecified). Most fatal cases had a basic level of education and the Araucanía Region had the highest mortality rate. There was a loss of life of 5022.04 years by the premature death of 293 people, with a ratio of 0.31 PYLL years lost per 1000 inhabitants. In the Araucanía Region this ratio increased to 1.03 PYLL years lost per 1000 inhabitants. Conclusions: The mortality rate tends to decrease, however this trend might mask regional differences. It should be noted that deaths caused by hydatidosis are preventable deaths and therefore unjust. Finally, the mortality analysis is important to better understand the burden of the disease and evaluate the effectiveness of public health interventions.

Introducción: La hidatidosis es una zoonosis universal de alto impacto socio-económico en Chile y en otras latitudes, siendo hoy para nuestro país una afección de notificación obligatoria en humanos. Objetivo: Caracterizar las defunciones por hidatidosis y establecer si existen diferencias de acuerdo a la región de residencia. Material y Métodos: Se utilizaron datos del Sistema de Defunciones (2000-2010) realizándose un análisis descriptivo. Resultados: El total de defunciones es de 293 (56% hombres). La tasa de mortalidad se ha desplazado desde 0,16 en 2000 a 0,11 en 2010 muertes por 100 mil habitantes. El mayor diagnóstico fue B67.9 (Equinococosis, otra y la no especificada). El nivel de instrucción de los afectados fue mayoritariamente básico. La Región de La Araucanía registra la mayor tasa de mortalidad. Se produjo la pérdida de 5.022,04 años de vida por el fallecimiento prematuro de 293 personas, con una razón de AVPP de 0,31 años de pérdida por 1.000 habitantes. En la Región de La Araucanía esta razón de AVPP se incrementa a 1,03 años de pérdida por 1.000 habitantes. Conclusiones: La tasa de mortalidad tiende a disminuir en el período estudiado; sin embargo, oculta diferencias regionales. Se destaca que las muertes por hidatidosis son muertes evitables y por lo tanto injustas. Finalmente, el análisis de mortalidad es importante para comprender de mejor forma la carga de la enfermedad y evaluar la efectividad de las intervenciones de salud pública.

Hidatidose: descubra o que é hidatidose e entenda o papel de cada um para prevenir essa doença. Profissional de saúde / Hydatidosis: find out what hydatidosis is and understand each person's role in preventing this disease. Health professional

Publicação para profissionais da saúde com orientações sobre o que é hidatidose e o papel de cada um para prevenir essa doença. (AU)

Hidatidose: descubra o que é hidatidose e entenda o papel de cada um para prevenir essa doença / Hydatidosis: find out what hydatidosis is and understand each person's role in preventing this disease

Publicação para a população em geral sobre o que é hidatidose e o papel de cada cidadão para prevenir essa doença. (AU)

Hidatidosis humana: antecedentes generales y situación epidemiológica en Chile, 2001-2009 / Human hydatidosis disease: general background and epidemiological situation in Chile, 2001-2009

Objective: To characterize the epidemiology of human hydatidosis in Chile. Material: Data from the Mandatory Disease Notification System (2001-2009), hospital discharges (2001-2008), Deaths (2001-2008) and Years of Potential Life Lost (2001-2008) were analyzed. Results: The average incidence, according to the mandatory notification data, was 1.9 cases per 100,000 inhabitants (men 51.4 percent). Median age was 38 years. Hospital discharge rate for the period was 6.3 discharges per 100,000 inhabitants. The main diagnosis corresponded to B67.9 (Echino-coccosis, other and unspecified). The average mortality rate was 0.2 deaths per 100,000 inhabitants. The level of education of fatalities was mainly basic. There was a loss of 3.349 years of life due to the premature death of 235 people. Conclusions: The incidence rates of cases reported, hospital discharges and mortality tend to decrease. There is a noteworthy discrepancy between reported cases and hospital discharges, which suggests underreporting. Improvement of the notification system and additional prevalence studies are required.

Objetivo: Caracterizar epidemiológicamente la hidatidosis humana en Chile. Material: Se utilizaron datos del Sistema de Notificación Obligatoria (2001-2009), Egresos hospitalarios (2001-2008), Defunciones (2001-2008) y Años de Vida Potencialmente Perdidos (2001-2008). Resultados: La incidencia promedio, según las notificaciones obligatorias fue 1,9 casos por 100 mil habs. (hombres 51,4 por ciento). Edad mediana 38 años. Egresos hospitalarios presentaron una tasa promedio de 6,3 egresos por 100 mil habs. El mayor diagnostico fue B67.9 (equinococosis, otra y la no especificada). La tasa de mortalidad promedio fue 0,2 defunciones por 100 mil habs. El nivel de instrucción de los afectados fue mayoritariamente básico. Se produjo la pérdida de 3.349 años de vida por el fallecimiento prematuro de 235 personas. Conclusiones: Las tasas de incidencia de casos notificados, egresos hospitalarios y mortalidad tienden a disminuir. Llama la atención la incongruencia entre los casos notificados y egresos hospitalarios, lo cual sugiere una sub-notificación. Se recomienda potenciar el sistema de notificación, confirmación de casos y estimular estudios de prevalencia.

[Human hydatidosis disease: general background and epidemiological situation in Chile, 2001-2009]. / Hidatidosis humana: antecedentes generales y situación epidemiológica en Chile, 2001-2009.

OBJECTIVE: To characterize the epidemiology of human hydatidosis in Chile. MATERIAL: Data from the Mandatory Disease Notification System (2001-2009), hospital discharges (2001-2008), Deaths (2001-2008) and Years of Potential Life Lost (2001-2008) were analyzed. RESULTS: The average incidence, according to the mandatory notification data, was 1.9 cases per 100,000 inhabitants (men 51.4%). Median age was 38 years. Hospital discharge rate for the period was 6.3 discharges per 100,000 inhabitants. The main diagnosis corresponded to B67.9 (Echinococcosis, other and unspecified). The average mortality rate was 0.2 deaths per 100,000 inhabitants. The level of education of fatalities was mainly basic. There was a loss of 3.349 years of life due to the premature death of 235 people. CONCLUSIONS: The incidence rates of cases reported, hospital discharges and mortality tend to decrease. There is a noteworthy discrepancy between reported cases and hospital discharges, which suggests underreporting. Improvement of the notification system and additional prevalence studies are required.

Epidemiología de la hidatidosis humana en la IX Región de La Araucanía Chile: 1991-1998 / Epidemiology of human hydatidosis in the IX Región of La Araucanía Chile: 1991-1998

In the region of la Araucania, locate in the south of Chile (37º24ï-39º34ï South lat.), the economy is based in cattle raising and agriculture. The case of human hydatidosis, mortality and notification registered in la Araucania 1991-1998 are reviewed. The rate for hydatid disease is 38.5 per 100,000 population. Liver (47.1 percent) and lung (40.7 percent) were the most affected viscera. Days in hospital, 11-20 the 56.1 percent. Disease in female is 51.1 percent. The mortality rate is 0.8 per 100,000, the most frecuently affected county is Imperial. The age 15-44 years is the most affected. The notification rate is 8.74 per 100,000 population. The rate for hydatid disease is higher than the rate of notification, then necessarily there exist a subnotification. We think that it is necessary to investigate the serological prevalence of hydatidosis in the population of the IX Región Araucania

[Epidemiology of human hydatidosis in the IX Region of la Araucania, Chile 1991-1998]. / Epidemiología de la hidatidosis humana en la IX región de la Araucanía, Chile. 1991-1998.

In the region of la Araucania, located in the south of Chile (37 degrees 24'-39 degrees 34' South lat.), the economy is based in cattle raising and agriculture. The cases of human hydatidosis, mortality and notification registered in la Araucania 1991-1998 are reviewed. The rate for hydatid disease is 38.5 per 100,000 population. Liver (47.1%) and lung (40.7%) were the most affected viscera. Days in hospital, 11-20 the 56.1%. Disease in female is 51.1%. The mortality rate is 0.8 per 100,000, the most frequently affected county is Imperial. The age group 15-44 years is the most affected. The notification rate is 8.74 per 100,000 population. The rate for hydatid disease is higher than the rate of notification, then necessarily there exist a subnotification. We think that it is necessary to investigate the serological prevalence of hydatidosis in the population of the IX Region Araucania.

[A universal method to correct underreporting of communicable diseases. Real incidence of hydatidosis in Chile, 1985-1994]. / Un método universal para corregir la subnotificación en enfermedades transmisibles. Incidencia real de la hidatidosis humana en Chile, 1985-1994.

BACKGROUND: There is evidence to postulate that undernotification is the reason for the great decrease in the reported incidence of hydatidosis in Chile. AIM: To develop and propose a method to assess the notification of transmissible diseases, based on observed lethality and hospital discharges. MATERIAL AND METHODS: Human hydatidosis in the period 1985-1994 was used as a model to develop the method. Official reports and mortality were analyzed first, determining the first lethality rate. A second lethality rate was calculated based on hospital discharges and a third, based on all Chilean surgical series published in the last two decades. Adjusting official notification of lethality to the true lethality according to surgical series, the number of unreported cases was calculated and the true incidence of hydatidosis was calculated, summing these cases to the official notification. RESULTS: According to this method, the real rates of human hydatidosis in the period 1985-1994, would fluctuate between 6.5 and 11.4 per 100,000. This figure is four times higher than the official notification in the analysed period. CONCLUSIONS: The correction of under notification based on hospital discharges, with or without correction for repeated hospital admissions, or real mortality of surgical series gave similar results, suggesting that both methods are correct.

Un método universal para corregir la subnotificación en enfermedades transmisibles: incidencia real de la hidatidosis humana en Chile: 1985-1994 / A method to correct undernotification of transmissible diseases: incidence of real human hydatidosis in Chile

Background: There is evidence to postulate that undernotification is the reason for the great decrease in the reported incidence of hydatidosis in Chile. Aim: To develop and propose a method to assess the notification of transmissible diseases, based on observed lethality and hospital discharges. Material and methods: Human hydatidosis in the period 1985-1994 was used as a model to develop the method. Official reports and mortality were analyzed first, determining the first lethality rate. A second lethality rate was calculated based on hospital discharges and a third, based on all Chilean surgical series published in the last two decades. Adjusting official notification of lethality to the true lethality according to surgical series, the number of unreported cases was calculated and the true incidence of hydatidosis was calculated, summing these cases to the official notification. Results: According to this method, the real rates of human hydatidosis in the period 1985-1994, would fluctuate between 6.5 and 11.4 per 100,000. This figure is four times higher than the official notification in the analysed period. Conclusions: The correction of under notification based on hospital discharges, with or without correction for repeated hospital admissions, or real mortality of surgical series gave similar results, suggesting that both methods are correct

Hidatidosis humana en Valdivia, Chile: encuesta retrospectiva en el Hospital Regional de Valdivia 1987-1991 / Human hydatidosis in Valdivia, Chile: retrospective survey at the Valdivia Regional Hospital 1987-1991

Se realizó una encuesta hospitalaria retrospectiva en el Hospital Regional de Valdivia con la finalidad de ubicar las fichas clínicas de los enfermos operados por hidatidosis en el período 1987-1991. Se cuantificó la morbilidad, mortalidad y letalidad por hidatidosis quirúrgica: para ello fueron calculadas las tasas de morbilidad, de mortalidad y de letalidad. Se registró información de importancia epidemiológica para cada uno de los pacientes intervenidos, la cual fue agrupada en distintas categorías. Se determinaron algunas características epidemiológicas descriptivas de la enfermedad. En el período de estudio se registraron 137 casos nuevos. La tasa de incidencia quirúrgica fue de 9,1 por cien mil habitantes. La tasa de mortalidad fue de 0,2 por cien mil habitantes y la tasa de letalidad fue de 2,2 por ciento. Entre los casos nuevos predominó el sexo femenino (51,8 por ciento) sobre el masculino (48,2 por ciento); la distribución por edad mostró que el grupo más frecuentemente afectado fue el de 10 a 19 años con el 30,7 por ciento; la distribución por ocupación reveló que el mayor porcentaje de enfermos eran dueñas de casa (29,2 por ciento) seguido de los escolares (23,2 por ciento). Las comunas más afectadas fueron Valdivia (23,4 por ciento), Panguipulli (17,5 por ciento) y la Unión (15,5 por ciento); la mayor proporción de operados fue de procedencia rural (73,7 por ciento)