[Influenza: a four-year evolution of the pandemic. Prof. Alejandro Posadas National Hospital, Argentina]. / Influenza: evolución a cuatro años de la pandemia. Hospital Nacional Profesor Alejandro Posadas, Argentina.

As from January to August 2013, epidemiological weeks 1-35 (EW), Influenza incidence, case characteristics, types and subtypes of circulating influenza virus in the Nacional Profesor Alejandro Posadas Hospital were studied, and were compared to incidences during 2009-2012. From late May to the end of August 2013 (EW18-35), an increase was observed in the proportion of patients' visits for respiratory disease, influenza-like illness and hospitalizations due to pneumonia; of 207 cases diagnosed with influenza A virus, 153 were infected by H1N1pdm09, 46 by H3, and eight without subtype. The highest proportion of cases was found in children under five years of age, followed by the group 60-64. The chances of having the illness were three times greater among the group 40-64 years old compared to 15-39 or those older than 64. Mortality, which increased with age, was 7.2%, and the odds of death were six times higher among those older than 64. Vaccination rate among the cases was 11.6%. None of the fatal cases had received the vaccine. After the 2009 pandemic, the proportions of annual patients' visits decreased until 2012; in 2013, an increase of 52.0% during the winter period compared to 2012. The viral circulation started earlier in 2013 compared to previous years. FLU-A(H1N1pdm) was the predominant circulating virus in 2009 and 2013, FLU-A(H3) in 2011, FLU-A(H3) and FLU-B in both 2010 and 2012.

[Pertussis: its evolution in Argentina at the end of the twentieth century]. / Evolución de la coqueluche en la Argentina a finales del siglo XX.

The objective of this study was to analize data of pertussis morbidity and mortality in Argentina and vaccination coverage with combined pertussis vaccine (DwPT), which was available from 1969 until 2000 inclusive, and to investigate their interrelation. A retrospective study was performed based on National Registers. Notification and mortality annual mean variation rates and geometric mean rates, by periods, were analyzed, and correlation coefficients between each one of them and with vaccination coverage were calculated. Notification annual mean variation rates for 1969-2000 were -14.34 and for 1980-2000 -17.26; mortality annual mean variation rates for 1980-2000 was -10.41. Vaccination coverage in infants up to one year of age (3 doses) was 44.4% in 1980; less than 60% until 1982 and higher than 80% after 1990. A highly significant inverse correlation was observed, between (a) vaccine implementation, increase in its coverage, introduction of a fifth vaccine dose, and (b) notification and mortality rates. It was observed during the study, that in our country there is a relatively little knowledge about disease occurrence in adults, and an apparent absence of population-based studies performed on the efficacy of erythromycin chemo prophylaxis in epidemics outbreaks. Based on these data, strategies for a better surveillance and control of pertussis, are exposed.

[Childhood tuberculosis and its diagnosis in Argentina]. / La tuberculosis infantil y su diagnóstico en la Argentina.

TB notification rate in infants and children 0-4 years was 24.3/100,000 in Argentina, in 2000, for a global incidence of 31.8/100,000. A 17% of all TB cases occurred in children (0-14 years), indicating a very active TB transmission. Usually TB is diagnosed when the disease is already advanced. Main criteria for the diagnosis are: a previous contact with an infectious TB patient, a positive PPD test result and clinical--radiological signs and symptoms. Bacteriology plays a limited role in diagnosis; gastric aspirate is the most often used specimen for bacteriological examination in children. Culture is performed on solid egg-media, but other more recently developed culture media systems are available in reference laboratories. Nucleic acid amplification assays are also used, but its systematic quality control is still lacking. Their results should be considered only as complementary. Strengthening of the laboratory network will contribute to increase diagnostic certainty of childhood TB, to improve reliability of cases reported, and to a better knowledge of the drug resistance profile. Early diagnosis of TB in children, by contacts investigation of infectious patients, followed by preventive chemotherapy or treatment when necessary, may revert the current epidemiological situation. TB meningitis in the 0-4 years group showed a significantly more pronounced decline than that of adults TB for the period 1980-2000, (only 10 meningitis cases were diagnosed in year 2000, 0.29/100,000), confirming the protection conferred by BCG vaccination when applied to newborns with a continuously high coverage.

Influenza: evolución a cuatro años de la pandemia: Hospital Nacional Profesor Alejandro Posadas, Argentina / Influenza: A four-year evolution of the pandemic: Prof. Alejandro Posadas National Hospital, Argentina

En el Hospital Nacional Profesor Alejandro Posadas se estudiaron la incidencia de influenza, las características de casos y tipos y subtipos de virus circulantes de enero a agosto de 2013 inclusive, semanas epidemiológicas (SE) 1-35, y se compararon con los años 2009-2012. De fin de mayo a agosto inclusive de 2013 (SE 18 a 35) se observó un aumento del porcentaje de consulta por enfermedades respiratorias, enfermedad tipo influenza e internación por neumonía y se diagnosticaron 207 casos: 153 influenza A (FLU-A)(H1N1pdm09), 46 A(H3), ocho A(sin subtipificar). La mayor frecuencia fue en menores de 5 años, seguida por el grupo de 60 a 64.La chance de tener la enfermedad fue tres veces mayor en el grupo de 40-64 años versus 15-39 o > 64 años. La letalidad, que aumentó con la edad, fue de 7.2% y la chance de morir fue seis veces mayor en los > 64 años. El porcentaje de vacunación entre los casos fue11.6%. Ninguno de los fallecidos estaba vacunado. Luego de la pandemia de 2009 el porcentaje de consultas anuales disminuyó hasta 2012, con un aumento en el período invernal de 2013 de 52.0% con respecto a 2012. La circulación viral en 2013 fue más temprana que en los años anteriores. En 2009 y 2013 la mayor circulación fue FLU-A (H1N1pdm), en 2011 FLU-A(H3) y en 2010 y 2012 FLU-A(H3) y FLU-B.

As from January to August 2013, epidemiological weeks 1-35 (EW), Influenza incidence, case characteristics, types and subtypes of circulating influenza virus in the Nacional Profesor Alejandro Posadas Hospital were studied, and were compared to incidences during 2009-2012. From late May to the end of August 2013 (EW18-35), an increase was observed in the proportion of patients' visits for respiratory disease, influenza-like illness and hospitalizations due to pneumonia; of 207 cases diagnosed with influenza A virus, 153 were infected by H1N1pdm09, 46 by H3, and eight without subtype. The highest proportion of cases was found in children under five years of age, followed by the group 60-64.The chances of having the illness were three times greater among the group 40-64 years old compared to 15-39 or those older than 64. Mortality, which increased with age, was 7.2%, and the odds of death were six times higher among those older than 64. Vaccination rate among the cases was 11.6%. None of the fatal cases had received the vaccine. After the 2009 pandemic, the proportions of annual patients´ visits decreased until 2012; in 2013, an increase of 52.0% during the winter period compared to 2012. The viral circulation started earlier in 2013 compared to previous years. FLU-A(H1N1pdm) was the predominant circulating virus in 2009 and 2013, FLU-A(H3) in 2011, FLU-A(H3) and FLU-B in both 2010 and 2012.

La tuberculosis infantil y su diagnostico en la Argentina / Childhood tuberculosis and its diagnosis in Argentina

La incidencia de tuberculosis (TBC) en menores de 5 años en Argentina fue 24.3/ 100.000 habitantes en el año 2000, y la tasa global 31.8/ 100.000. Un 17% de los casos fueron menores de 15 años, lo que indica una activa transmisión de la infección, que se diagnostica generalmente ya con enfermedad avanzada, por la historia de foco, la reacción tuberculínica positiva, y los signos y síntomas clínico- radiológicos. El aporte de la bacteriología al diagnóstico es escaso, empleándose en 0-4 años el aspirado o lavado gástrico. Para el cultivose usan los medios sólidos a base de huevo o, en laboratorios de referencia, los de detección temprana. Las prue-bas de amplificación de ácidos nucleicos están disponibles en algunos laboratorios, pero sin un sistema de garan-tía de calidad; sus resultados deben considerarse sólo dentro del contexto clínico. El fortalecimiento de la red de laboratorios de cultivo facilitará el diagnóstico de certeza de la TBC infantil, la confiabilidad de la notificación, y el conocimiento de la resistencia bacteriana. Para revertir la actual situación epidemiológica es necesario incremen-tar la investigación de los niños contactos de casos bacilíferos, seguida de quimioprofilaxis o tratamiento según corresponda. La meningitis TBC en menores de 5 años tuvo una disminución significativamente mayor que la de laTBC en adultos, en los últimos 20 años en Argentina. En 2000 se notificaron sólo 10 casos de meningitis en esasedades (0.29/ 100.000). Esto confirma la protección conferida por la vacunación BCG al nacimiento, con alta y con-tinuada cobertura