Down's syndrome is a risk factor for severe lower respiratory tract infection due to respiratory syncytial virus.

AIM: Previous studies have suggested that Down's syndrome is an independent risk factor for severe respiratory infection due to respiratory syncytial virus (RSV). We compared the clinical characteristics of children with and without Down's syndrome hospitalised due to RSV. METHODS: This retrospective cohort study compared data from hospitalisations due to RSV lower respiratory tract infections (LRTI) in children under 14 years of age with (n = 58) and without (n = 58) Down's syndrome. RESULTS: The Down's group had longer hospital stays than the controls of six versus four days (p < 0.0001), even after adjusting for age, weeks of gestation at birth, presence of asthma, bronchopulmonary dysplasia, haemodynamically significant and nonsignificant congenital heart disease. This difference increased when only children under one year of age were analysed to 11 versus five days (p < 0.0001). Children with Down's syndrome were more likely to be admitted to intensive care unit (43.1% versus 22.4%, p = 0.017), need noninvasive mechanical ventilation (36.2% versus 13.7%, p = 0.005) and be prescribed antibiotics and steroids. CONCLUSION: Children with Down's syndrome hospitalised due to RSV LRTI had longer hospital stays and worse clinical courses than controls, highlighting the need for RSV prophylaxis for children with Down's syndrome, especially under one year of age.

The effects of pre-pregnancy BMI and maternal factors on the timing of adiposity rebound in offspring.

OBJECTIVE: To assess the effect of pre-pregnancy body mass index (BMI), gestational weight gain (GWG), and other maternal factors on the timing of adiposity rebound (AR). METHODS: In this study, 594 mothers (mothers who do not have diabetes and not underweight) from the longitudinal Growth and Obesity Chilean Cohort Study self-reported their weights at the beginning and end of their pregnancies, and their heights were measured. Pre-pregnancy BMI was categorized as normal weight, overweight, or obesity, and GWG was assessed according to Institute of Medicine guidelines. For children, weight and height measurements from 0 to 3 years were retrieved from records, and they were measured from age 4 to 7 years. BMI curves from 0 to 7 years were used to estimate the age at AR, which was categorized as early (<5 years), intermediate (5-7 years), or late (>7 years). The associations between pre-pregnancy BMI and GWG and early AR were tested using logistic regression models. RESULTS: In total, 33% of the mothers had excess pre-pregnancy weight, 31.2% exceeded Institute of Medicine recommendations, and 45% of children had early AR. The pre-pregnancy BMI and parity were associated with earlier AR (OR = 1.07, 95% CI = 1.02-1.11; OR = 0.86; 95% CI = 0.74-0.99, respectively), but GWG was unrelated. CONCLUSIONS: These results suggest that preventive strategies for promoting normal pre-pregnancy BMI, especially in women's first pregnancies, could delay the timing of AR, with protective metabolic effects on offspring.

Tos ferina: una enfermedad que resurge en Chile / Whooping cough: resurrection of a disease in Chile

La tos ferina corresponde a una enfermedad inmunoprevenible de notificación obligatoria, que presentaba una baja incidencia desde la década de los ochenta en Chile. Actualmente, a pesar de las estrategias de vacunación, esta enfermedad sigue constituyendo un problema de salud pública, debido a las dificultades que implican su prevención y control en la población. La tasa de notificación de tos ferina en Chile, durante los años 2009 y 2010, se encuentra dentro de lo esperado en relación a la incidencia de esta enfermedad observada en años anteriores. Sin embargo, durante el último trimestre del año 2010 se observa un importante aumento de casos, situación que se prolonga hasta el final de este período. El grupo más afectado de la población corresponde a los niños menores de 1 año, especialmente en los menores de 6 meses, que aún no cuentan con su esquema de vacunación primario completo. La situación epidemiológica nacional es concordante con lo publicado en otros países que también han registrado un aumento de casos durante los últimos años. Dado el aumento de notificaciones registradas en el último período, resulta aún más importante mantener una buena vigilancia y así contar con información epidemiológica adecuada, que permita implementar estrategias de control eficaces de la tos ferina en Chile.

Whooping cough corresponds to a vaccine-preventable disease of mandatory notification, of low incidence since eighties decade in Chile. Nowadays, despite vaccine strategies, it continues to remain a public health problem due to difficulties involvingpopulation prevention and control. Notification rate of whooping cough in Chile, during 2009 and 2010, is within expected in relation to incidence of this disease in previous years. However, during 2010 last term, it is observed an important rise of cases, situation that is prolonged until the end of this period. The most affected population group corresponds to children less than 1 year old, especially those less than 6 months old that have not completed their primary vaccination scheme.National epidemiologic situation is according to what has been published in other countries that have also registered an increase in the number of cases during the last years. Given the rice in notifications during the last period, it seems even more important to maintain a good surveillance and have adequate epidemiological information that allows implementing effective control strategies in Chile.

Vigilancia epidemiológica de las parálisis flácidas agudas / Epidemiologic surveillance of acute flaccid paralysis

Las parálisis flácidas agudas (PFA) constituyen un complejo síndrome con una amplia gama de posibles etiologías, entre las cuales se encuentran la poliomielitis y el síndrome de Guillain-Barré (SGB). Su vigilancia tiene una gran importancia en salud pública, debido a la iniciativa mundial de erradicar la poliomielitis y a los posibles efectos adversos de la vacunación masiva contra la influenza A(H1N1), la cual pudiese estar asociada al SGB. Durante los años 2009 y 2010 no se reportaron casos de poliomielitis en nuestro país ni en la región de las Américas. Sin embargo, dada la situación epidemiológica mundial de esta enfermedad resulta fundamental mantener buenas coberturas de vacunación y un sistema de vigilancia adecuado. En relación a la vigilancia del SGB posterior a la implementación de la vacunación masiva contra la influenza A(H1N1), no se observó un aumento significativo de casos en niños y tampoco se logró establecer asociación entre la inmunización y la aparición de esta enfermedad en adultos.

Acute flaccid paralysis constitutes a complex syndrome with a wide spectrum of possible etiologies, among whom are poliomyelitis and Guillain-Barré syndrome. Its surveillance has great importance to public health due to the polio eradication world initiative and the possible adverse effects of mass vaccination against influenza A(H1N1). During 2009 and 2010, no poliomyelitis cases were reported in our country nor American region. However, given the world epidemiologic situation ofthis disease, it is essential to maintain adequate vaccination coverage and surveillance system. Related to Guillain-Barré syndrome surveillance after influenza A(H1N1) mass vaccination implementation, no significant increase in cases among children was observed, and no association between immunization and adult disease occurrence could be established.