A Barrasa

Publications (10)22.42 Total impact

• Article: Salmonella Kottbus outbreak in infants in Gran Canaria (Spain), caused by bottled water, August-November 2006.

  R Palmera-Suárez, P García, A García, A Barrasa, D Herrera
  Euro surveillance: bulletin europeen sur les maladies transmissibles = European communicable disease bulletin 08/2007; 12(7):E070712.2. · 6.15 Impact Factor
• Article: Sentinel surveillance of HIV infection in HIV test clinics, Spain 1992-2002.

  A Barrasa, J Castilla, J del Romero, I Pueyo, C de Armas, J A Varela, J M Ureña, F J Bru, J R Ordoñana, L M Sáez de Vicuña
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  ABSTRACT: HIV infection in Spain was monitored in persons undergoing voluntary HIV testing in ten sentinel clinics between 1992 and 2002. Only patients on their first visit were considered for inclusion, and their numbers rose from 4426 in 1992 to 6649 in 2002. Most of them recognised their risk exposure as heterosexual. The proportion of injecting drug users decreased from 19% to 2% of the study population, and the proportion of female sex workers increased from 6% to 26%. The number of patients diagnosed with HIV infection declined from 604 in 1992 to 153 in 2002, and HIV prevalence fell from 13.6% to 2.3% in the same period. In all risk exposure categories, a decrease in HIV prevalence was observed, more pronounced during the first few years and stabilised in the later years. In 2002, the highest HIV prevalence was found in injecting drug users (IDUs) (14.2%), homo/bisexual men (7.5%) and individuals who had an HIV infected heterosexual partner (10.2%).
  Euro surveillance: bulletin europeen sur les maladies transmissibles = European communicable disease bulletin 06/2004; 9(5):27-9. · 6.15 Impact Factor
• Article: [Prevalence of the HIV infection in patients seen at specialized diagnosis centers in 9 cities in Spain from 1992 to 2001].

  A Barrasa, J Del Romero, I Pueyo, C de Armas, J A Varela, J M Ureña, F J Bru, M V Aguanell, J R Ordoñana, J Balaguer, L M Sáez de Vicuña, J Castilla
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  ABSTRACT: To describe the prevalence of HIV infection in persons tested between 1992 and 2001. Descriptive, cross-sectional epidemiological study. 10 ambulatory centers specialized in diagnosing HIV, located in 9 cities in Spain. 53,183 persons older than 12 years, tested for the first time for HIV. Number of persons tested per year, number of persons diagnosed as seropositive for HIV according to sex, age group and category of exposure. The number of persons tested increased from 4401 in 1992 to 6407 in 2001. Approximately half reported heterosexual risk exposure/exposure through high-risk heterosexual behaviors, excluding prostitution. Intravenous drug users (IVDU) increased from 15.3% in 1992-1993 to 1.4% in 2000-2001, and women prostitutes/female sex workers increased from 6.7% to 25.1%. A total of 2898 persons were diagnosed as having HIV infection; 78% of them were men. The number of diagnoses decreased from a high of 1058 in 1992-1993 to 304 in 2000-2001, and this trend was seen for all categories of exposure except female prostitutes and men with heterosexual risk factors. The prevalence decreased from 14% in 1992 to 2% in 2001. There were decreases in all categories of exposure, especially during the first years of the study, with a tendency to level off. In 2001 the prevalence figures were 23.8% for IVDU, 7.9% for homosexual men and women, 0.8% for female sex workers and 1% for other heterosexual men and women. The specialized diagnostic centers play an important role in diagnosing HIV, and this service complements primary care services. Greater efforts are needed in the prevention of HIV infection.
  Atención Primaria 06/2004; 33(9):483-8. · 0.63 Impact Factor
• Article: Progression of HIV infection and mortality by hepatitis C infection in patients with haemophilia over 20 years.

  M Quintana, J del Amo, A Barrasa, S Pérez-Hoyos, I Ferreros, F Hernández, A Villar, V Jiménez, F Bolúmar
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  ABSTRACT: Hepatitis C virus (HCV) infection is an important cause of mortality in human immune deficiency virus (HIV)-positive haemophiliacs. This study describes progression to AIDS, death from HCV end-stage liver disease (ESLD) and all-cause mortality over 20 years. All HIV-positive haemophiliacs in La Paz University Hospital were included in this cohort. HIV seroconversion was estimated using mathematical techniques for interval-censored data from 1979 to 1985. Poisson regression was used to estimate rates of AIDS, death from ESLD and all causes in different periods: before 1988, 1988-89, 1990-91, 1992-93, 1994-95, 1996-97 and 1998-2001 using competing risk models. Among 383 cohort members, global AIDS incidence was 9.7 per 100 person-years, peaking in 1992-93 and dropping by 87% in 1998-2001 compared with before 1988 [incidence rate ratio (IRR) 0.13; 95% CI: 0.03-0.53]. Overall mortality was 7.5 per 100 person-years, was highest from 1992 to 1997, and fell by 66% in 1998-2001 compared with before 1988 (IRR 0.34; 95% CI: 0.14-0.81). Eighteen (5%) persons died of ESLD which represented 19% of deaths before 1988, 4% during 1988-89, 1990-91 and 1992-93, 2% in 1994-95, 10% in 1996-97 and 33% in 1998-2001. Overall death rate from ESLD was 0.5 cases per 100 person-years with no statistically significant trend observed over time. Important reductions in HIV disease progression to AIDS and death have been observed from 1998 to 2001, and can be attributed to highly active antiretroviral therapy. Although no increase in the rate of HCV-related deaths can be demonstrated, HCV accounts for an increasing proportion of deaths in the recent years.
  Haemophilia 10/2003; 9(5):605-12. · 2.60 Impact Factor
• Article: Brote de varicela en Herrera del Duque (Badajoz)

  F.J. Valadés, A Barrasa, E Peña, J F Sánchez, C Amela, I Pachón, D Herrera, F Martínez Navarro, J M Ramos
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  ABSTRACT: Introducción: La varicela es una enfermedad de distribución mundial con una elevada morbilidad y pocas complicaciones, aunque puede presentar cuadros clínicos graves en inmunodeprimidos y adultos sanos. El objeto de este estudio es identificar y describir las características y los costes de un brote epidémico en Extremadura, cuya tasa anual de casos declarados al sistema de Enfermedades de Declaración Obligatoria (EDO) oscila en alrededor de 5 por 1.000 habitantes. Métodos: Estudio descriptivo con búsqueda activa de casos entre los meses de noviembre del año 2000 y marzo de 2001, y de la susceptibilidad de la cohorte escolarizada del colegio de Herrera del Duque (Badajoz). Las definiciones de casos fueron recogidas de los protocolos de la Red de Vigilancia de la comunidad extremeña. La confirmación microbiológica se realizó por aislamiento del virus y por presencia de marcadores IgM e IgG en el suero del enfermo. Se analizaron los costes tangibles directos e indirectos y los no tangibles del brote. Resultados: De los 75 casos identificados, 71 (94,7%) eran niños de entre uno y 9 años, predominando el sexo masculino. La tasa de ataque fue de 18,5 casos por 1.000 habitantes, y del 68,2% en convivientes menores de 10 años. La evolución fue benigna, sin ingresos hospitalarios ni complicaciones. Se encontró un 71,6% de niños susceptibles en los de entre 3 y 8 años. Se analizó una posible agregación temporal de casos en el colegio, obteniéndose un riesgo relativo (RR) de 5,01 (p < 0,001). Se aisló el virus en las 4 muestras de vesículas estudiadas y la serología (IgM) fue positiva en los 9 sueros estudiados. El coste total de brote fue de 927,21 e, con una media de 12,53 e por caso, y 205 días de pérdida escolar. Conclusión: Se confirmó la existencia de un brote de varicela en el colegio de la localidad de Herrera del Duque, con transmisión persona a persona, que afectó a niños de entre uno y 9 años. La elevada susceptibilidad del alumnado, las características de la docencia y las reuniones previas a los carnavales tuvieron un papel determinante en la propagación de la epidemia. El coste estimado para este brote se corresponde con un gasto un 76% menor del producido por la vacunación con una dosis de los 75 casos de este brote.
  Gaceta Sanitaria. 01/2003;
• Article: [HIV prevalence among homosexual and bisexual men in Spain, 1992-2000].

  J del Romero, C Rodríguez, S García, J Ballesteros, P Clavo, M A Neila, S del Corral, I Pueyo, M A Mendo, C P Torrego, [......], A M Burgos, J R Ordoñana, J J Gutiérrez, J Ballester, J Balaguer, J Ortueta, L M Sáez de Vicuña, P Sobrino, A Barrasa, J Castilla
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  ABSTRACT: Our purpose was to describe the time trend in HIV seroprevalence among homo/ bisexual men. We analyzed 9,383 homo/ bisexual men who had a first voluntary test for HIV in 10 Spanish clinics from 1992 to 2000. HIV prevalence decreased from 20.3% in 1992 to 8.4% in 2000. In the multivariate analysis this decline appeared independently associated with the testing year and the birth cohort. New generations of voluntarily tested homo/bisexual men are less infected by HIV, but it is yet necessary to intensify the prevention programs.
  Medicina Clínica 11/2002; 119(11):413-5. · 1.38 Impact Factor
• Article: Factors influencing HIV progression in a seroconverter cohort in Madrid from 1985 to 1999.

  J del Amo, J del Romero, A Barrasa, S Pérez-Hoyos, C Rodríguez, M Díez, S García, V Soriano, J Castilla
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  ABSTRACT: To study HIV progression from seroconversion over a 15 year period and measure the population effectiveness of highly active antiretroviral therapy (HAART). A cohort study of people with well documented dates of seroconversion. Cumulative risk of AIDS and death were calculated by extended Kaplan-Meier allowing for late entry. Cox proportional hazards models were used to study variables associated with HIV progression. To assess the impact of HAART, calendar time was divided in three periods; before 1992, 1992-6, and 1997-9. From January 1985 to May 2000, 226 seroconverters were identified. The median seroconversion interval was 11 months, median seroconversion date was March 1993. 202 (89%) were men, 76% of whom were homo/bisexual. A 66% reduction in progression to AIDS was observed in 1997-9 compared to 1992-96 (HR 0.34 95% CI: 0.16 to 0.70). People with primary education appeared to have faster progression to AIDS compared to those with university studies (HR 2.69 95%CI: 1.17 to 6.16). An 82% reduction in mortality from HIV seroconversion was observed in 1997-9 (HR 0.18 95% CI: 0.05 to 0.68) compared to 1992-6. Progression to death for people with primary education was twice as fast as for those with university education (p 0.0007). People without confirmation of an HIV negative test had faster progression (HR 4.47 95% CI: 1.18 to 16.92). The reduction in progression to AIDS and death from seroconversion from 1992-6 to 1997-9 in Madrid is likely to be attributable to HAART. HIV progression was faster in subjects with primary education; better educational level may be associated with better adherence to medication.
  Sexually Transmitted Infections 09/2002; 78(4):255-60. · 2.85 Impact Factor
• Article: [Estimating the completeness of AIDS reporting in Spain].

  A Barrasa, J Castilla, J Pereira, D Herrera, F Martínez-Navarro
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  ABSTRACT: To evaluate AIDS case reporting in the Spanish regions as compared with the AIDS deaths registered in mortality statistics, in order to identify possible deviations indicative of underreporting. We carried out an ecological analysis taking each region as a unit. We compared incidence and mortality obtained from the AIDS reporting system with the HIV/AIDS deaths obtained from the mortality statistics of the Spanish Institute for Statistics. The 1986-1998 period was analysed globally, then the analysis was repeated for the 1995-1998 period. In the 1986-1998 period there was a good correlation (r = 0.93) between the AIDS incidence rates and HIV/AIDS mortality rates obtained from death statistics. Some regions presented an AIDS incidence lower than expected according to their mortality rate when it was compared with the national average, with Asturias (27%), Comunidad Valenciana (26%), Andalucia (20%), Ceuta (18%) and Cantabria (13%) standing out. Taking as a reference the five regions with the highest completeness, the underreporting in Spain was of 13%. In the 1995-1998 period these deviations increased moderately. In the 1986-1998 period, 18.9% less deaths were notified to the AIDS reporting system in comparison with death statistics, showing a great variability between regions. In Spain the reporting level of AIDS cases is acceptable for the aims of surveillance, although in some regions measures to improve it should be taken. The notification of deaths to the AIDS reporting system presents great deficiencies.
  Gaceta Sanitaria 15(6):482-9. · 1.33 Impact Factor
• Article: [Chickenpox outbreak in Herrera del Duque, Badajoz, Spain].

  F J Valadés, A Barrasa, E Peña, J F Sánchez, C Amela, I Pachón, D Herrera, F Martínez-Navarro, J M Ramos
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  ABSTRACT: Chickenpox is a worldwide disease with high morbidity but few complications, although complications can be sevre in immunocompromised individuals and healthy adults. The annual chickenpox rate declared to the National Notification Disease Surveillance System is approximately 5 cases per 1,000 inhabitants in Extremadura (Spain). The aim of this study was to identify and describe the characteristics and cost of an epidemic outbreak of chickenpox in Extremadura. Between November 2000 and March 2001, a descriptive study was performed. Cases of chickenpox were actively sought in a cohort of schoolchildren in Herrera del Duque (Badajoz). The protocols of the Monitoring Network of the Autonomous Community of Extremadura was used for case definition. Microbiological confirmation was performed by isolation of the virus and the presence of IgM and IgG markers in serum. We analyzed the direct and indirect tangible costs as well as the intangible costs of the outbreak. Seventy-five cases were identified, of which 94.7% occurred in children aged between 1-9 years, mainly boys. The attack rate was 18.5 cases per 1,000 inhabitants and 68.2% occurred in children aged less than 10 years charing a home. The clinical course was benign, without hospital admissions or complications. A total of 71.6% of children aged between 3 and 8 years were susceptible. A possible temporary aggregation of cases in the school was analyzed and a relative risk of 5.01 (p < 0.0001) was obtained. The virus was isolated in the 4 vesicle samples studied and serology was positive (IgM) in the 9 serum samples studied. The total cost of the outbreak was of 927,21 e, with a mean of 12,53 e per case and 205 school days lost. A chickenpox outbreack was confirmed in Herrera del Duque, with person-to-person transmission, affecting children aged between 1 and 9 years. The high susceptibility of the pupils, the characteristics of teaching, and the meetings prior to the carnivals played a determining role in the transmission of the epidemic. The estimated cost of this outbreak was 76% less than the cost that would have been generated by single-dose vaccination of the 75 individuals who contracted the disease.
  Gaceta Sanitaria 17(3):196-203. · 1.33 Impact Factor
• Source

  Available from: Jorge Del Romero

  Article: Prevalencia de VIH entre las personas de ocho ciudades españolas que se realizan la serología tras exposiciones heterosexuales, 1992-2003

  Isabel Pueyo, C de Armas, José Antonio Varela, J M Ureña, F J Bru, Juan Ramón Ordoñana Martín, Jordi Balaguer, L M Sáez de Vicuña, A Barrasa, Jesús Castilla Catalán, Jorge del Romero
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  ABSTRACT: Fundamento: La epidemia de infecciones por el virus de la inmunodeficiencia humana (VIH) en España se caracterizó durante los primeros años por el predominio de casos en personas usuarias de drogas inyectadas, pero en la actualidad todo parece apuntar a un progresivo predominio de la transmisión sexual. El objetivo de este trabajo es describir la evolución en la prevalencia de VIH en varios grupos de población heterosexual y caracterizar las situaciones en las que se produjeron las infecciones.
  Revista española de salud pública, ISSN 1135-5727, Vol. 78, Nº. 6, 2004, pags. 669-677.