[Epidemiology of cysticercosis in Chile]. / Riesgo y distribución geográfica de neurocisticercosis en Chile según egresos hospitalarios (2002-2019).

BACKGROUND: Neurocysticercosis is the most prevalent parasitic disease of the central nervous system in Chile, where sporadic cases are reported, without information about the epidemiology or distribution of the disease. AIM: To identify the main risk zones for cysticercosis in Chile. MATERIAL AND METHODS: Analysis of hospital discharge databases between 2002 and 2019, available at the website of the Chilean Ministry of Health. Cases with B69 code of the tenth international classification of diseases were identified. RESULTS: In the study period, there were 1752 discharges with the diagnoses of neurocysticercosis, ocular cysticercosis and cysticercosis of other sites. The ages of patients ranged from 0 to 89 years with a clustering between 30 and 59 years. Sixty two percent were males. The zone between the regions of Maule and Araucania concentrated 82% of cases. CONCLUSIONS: We identified the zone with the greatest concentration of cysticercosis in Chile, where preventive strategies should eventually be directed.

Chagas disease in northern Chile: Detection of Trypanosoma cruzi in children, dogs and triatomine bugs.

Chagas disease is an anthropozoonotic disease caused by the protozoan Trypanosoma cruzi, transmitted by triatomine vectors. In Chile, there are four species of triatomine bugs that are potential vectors of T. cruzi, being Triatoma infestans the main vector in endemic areas of the country. The "Programa Nacional de Control Vectorial de la Enfermedad de Chagas de Chile" has significantly reduced the rates of home infestation to less than 1% and has interrupted vectorial transmission since 1999. The objective of this study was to evaluate the impact of vectorial control and the continuity of the interruption of vectorial transmission in northern Chile (provincia de El Loa, región de Antofagasta). The study comprised fingerstick blood samples of 2104 children, attending local school, venous blood samples of 65 dogs, associated to houses with T. infestans unique findings and vector infestation, and intestine samples of 284 T. infestans specimens, from the provincia de El Loa, during 2014-2016 period. The samples were analyzed by enzyme-linked immunosorbent assay (ELISA), indirect immunofluorescence and/or polymerase chain reaction (PCR) techniques. A total of 5 children (0.24%), 7 dogs (10.8%), and 6 specimens of T. infestans (2.1%) resulted positive to T. cruzi infection. This study showed that the risk of transmission of Chagas disease is low in the north of Chile (provincia de El Loa), detected a low positive rate of chagasic children and of infected triatomine bugs, and showed the existence of T. cruzi transmission in dogs, which are used as natural sentinels for the detection of T. cruzi infection, being especially useful during surveillance program in human population characterized by low seroprevalence.

Riesgo y distribución geográfica de neurocisticercosis en Chile según egresos hospitalarios (2002-2019) / Epidemiology of cysticercosis in Chile

BACKGROUND: Neurocysticercosis is the most prevalent parasitic disease of the central nervous system in Chile, where sporadic cases are reported, without information about the epidemiology or distribution of the disease. AIM: To identify the main risk zones for cysticercosis in Chile. MATERIAL AND METHODS: Analysis of hospital discharge databases between 2002 and 2019, available at the website of the Chilean Ministry of Health. Cases with B69 code of the tenth international classification of diseases were identified. RESULTS: In the study period, there were 1752 discharges with the diagnoses of neurocysticercosis, ocular cysticercosis and cysticercosis of other sites. The ages of patients ranged from 0 to 89 years with a clustering between 30 and 59 years. Sixty two percent were males. The zone between the regions of Maule and Araucania concentrated 82% of cases. CONCLUSIONS: We identified the zone with the greatest concentration of cysticercosis in Chile, where preventive strategies should eventually be directed.

Atovaquone/Proguanil Resistance in an Imported Malaria Case in Chile.

In November 2018, we diagnosed a cluster of falciparum malaria cases in three Chilean travelers returning from Nigeria. Two patients were treated with sequential intravenous artesunate plus oral atovaquone/proguanil (AP) and one with oral AP. The third patient, a 23-year-old man, presented with fever on day 29 after oral AP treatment and was diagnosed with recrudescent falciparum malaria. The patient was then treated with oral mefloquine, followed by clinical recovery and resolution of parasitemia. Analysis of day 0 and follow-up blood samples, collected on days 9, 29, 34, 64, and 83, revealed that parasitemia had initially decreased but then increased on day 29. Sequencing confirmed Tyr268Cys mutation in the cytochrome b gene, associated with atovaquone resistance, in isolates collected on days 29 and 34 and P. falciparum dihydrofolate reductase mutation Asn51Ile, associated with proguanil resistance in all successfully sequenced samples. Molecular characterization of imported malaria contributes to clinical management in non-endemic countries, helps ascertain the appropriateness of antimalarial treatment policies, and contributes to the reporting of drug resistance patterns from endemic regions.

FREQUENCY OF ANTI- Toxocara spp. ANTIBODIES IN INDIVIDUALS ATTENDED BY THE CENTRO DE SALUD FAMILIAR AND ENVIRONMENTAL CONTAMINATION WITH Toxocara canis EGGS IN DOG FECES, IN THE COASTAL NIEBLA TOWN, CHILE.

The frequency of anti-Toxocara spp. antibodies in individuals attended by the Centro de Salud Familiar in the coastal Niebla town, Chile, was related to the host and to environmental factors. IgG anti- Toxocara antibodies were detected with a commercial ELISA kit (SCIMEDX Corporation, USA). Samples with undetermined absorbance values were subjected to an additional ELISA standardized by the Instituto de Salud Pública, Chilean Health Ministry, a commercial ELISA (NOVATEC, Germany), and a commercial Western blot kit (LDBio Diagnostics, France). Hematological exams were performed using an automated blood counter and blood smears. Dog feces were collected from the ground along the main road in Niebla, including rural and urban locations. Ninety (25.4%) of the 355 examined individuals were positive by the ELISA test. The frequency of anti-Toxocara antibodies and the infection risk were significantly higher (p < 0.05) among those individuals ≥ 40 years old with respect to the 20-39 years old group, in individuals from rural locations, those who did not have a safe drinking water supply in the house or who presented blood eosinophilia. The proportion of positive samples of dog feces and the mean number of Toxocara canis eggs/g of feces in urban and rural areas were similar (p > 0.05).

La enfermedad de Chagas en Chile: componente vectorial y serología en menores de 5 años durante el período 2005-2010 / Chagas disease in Chile: vector component and serology in children below 5 years old during period 2005-2010

La enfermedad de Chagas afecta a más de 18 millones de personas en el mundo, incluyendo a cerca de 120.000 en el país. El principal vector de esta enfermedad en Chile es Triatoma infestans. En el laboratorio de entomología médica del ISP se han analizado 2.193 ejemplares de triatominos. Las Secretarías Regionales Ministeriales (SEREMIS) de Atacama, Valparaíso y Metropolitana reúnen en conjunto al 93,84 por ciento del total de triatominos + hemípteros (2.058) capturados en el período. La SEREMI con el mayor número de capturas y envíos es la de Valparaíso, específicamente la oficina provincial de Aconcagua, con un 49,15 por ciento del total. Al analizar, la totalidad de triatominos en laboratorio desde el año 2005 hasta 2010 y considerando el índice tripano/triatomineo, se observa un índice de infestación final de 28,5 por ciento. Paralelamente a los estudios con el vector, se realizaron una serie de estudios de tamizaje serológico en niños menores de 5 años y sus familias entre las regiones de Arica y Parinacota y O’Higgins. Se realizaron 5.111 tamizajes, encontrando 28 casos positivos con una positividad del 0,55 por ciento, valor cercano al 0,7 por ciento de prevalencia obtenida por la Encuesta Nacional de Salud (ENS) 2009-2010.

Chagas’ disease affects over 18 million people including about 150,000 in the country. The main vector of this disease in Chile is Triatoma infestans. The medical entomology laboratory ISP, analyzed 2 193 samples of triatomine. The Regional Ministerial Secretariats (SEREMIS) of Atacama, Valparaiso and Metropolitana gather together a 93.84 percent of triatomine + hemiptera (2 058) captured in the period. The SEREMI with the highest number of catches and services is Valparaiso, specifically the Aconcagua provincial office with 49.15 percent of the total. The analysis of all triatomines in the laboratory from 2005 to 2010 and considering the trypan / triatominae index, there is a final infestation rate of 28.5 percent. Parallel to the studies with the vector, there was a series of studies for serological screening in children under 5 and their families between the regions of Arica and Parinacota and O’Higgins. Five thousand one hundred and eleven screenings have been conducted and found 28 positive cases with a positivity of 0.55 percent, a value close to 0.7 percent prevalence obtained by the National Health Survey (NHS) 2009-2010.