tetano
Editor, Senior Moderator
Acta Med Port. 2012 Sep;25(5):277-87. Epub 2012 Nov 12.
[National influenza surveillance programme: results of influenza activity in portugal in the 2010/2011 season].
[Article in Portuguese]
Pechirra P, Gon?alves P, Conde P, Nunes B, Guiomar R.
Source
Departamento de Doen?as Infecciosas. Instituto Nacional de Sa?de Doutor Ricardo Jorge. Lisboa. Portugal.
Abstract
Introduction: Epidemiological surveillance of influenza, a disease associated with high mortality in the elderly and individuals' belongingto risk groups, is essential for the characterization of influenza epidemics as well as for the monitoring of outbreaks and the emergenceof viral strains resistant to antivirals.Material and Methods: In the present study was analyzed the influenza surveillance data from 2010/2011 winter. The clinical, epidemiologicaland virological data related to cases of flu-like syndrome have been collected through the National Influenza SurveillanceProgramme, coordinated by the National Influenza Reference Laboratory (LNRVG) in collaboration with the Department of Epidemiology(DEP) of the National Institute of Health Doutor Ricardo Jorge (INSA) and the Directorate-General for Health (DGS).Results: From the analysis of the data collected during the 2010/2011 winter season, influenza activity was moderate / high with anepidemic period of 8 weeks between week 50/2010 and 5 / 2011, with a peak of 121, 12 cases per 100 000 population in week 52/2010.Discussion: The influenza B viruses (Victoria lineage) predominated in the early period to week 1 / 2011, when became to predominateinfluenza A(H1)pdm09 viruses. The largest proportion of cases of influenza was found in the age group of children between 5 and 14years old. The viruses characterized antigenically and genetically were similar to strains included in the seasonal influenza vaccine2010/2011, presenting some amino acid substitutions in antigenic sites. Most strains of A(H1)pdm09 influenza virus still remain sensitiveto oseltamivir and zanamivir, although were detected sporadic cases of oseltamivir resistant viruses. To date, the LNRVG detectedthe presence of the H275Y substitution in the neuraminidase gene, associated with oseltamivir resistance, in three virus A(H1)pdm09.For one of them, oseltamivir resistance was confirmed by phenotypic assays.Conclusion: Despite fears associated with the emergence of a new pandemic virus (rapid spread, high morbidity and mortality), theclinical and epidemiological characteristics of infection with influenza A(H1)pdm09, proved in the course of two seasons (2009/2010and 2010/2011) to be very similar to seasonal flu. Is however noteworthy that during the pandemic season(2009/2010) the influenzavirus A (H1N1) pdm09 were linked with particular characteristics with regard to their temporal distribution, age groups most affected,severe infections and death and associated risk factors.
PMID:
23211197
[PubMed - in process]
http://www.ncbi.nlm.nih.gov/pubmed/23211197
[National influenza surveillance programme: results of influenza activity in portugal in the 2010/2011 season].
[Article in Portuguese]
Pechirra P, Gon?alves P, Conde P, Nunes B, Guiomar R.
Source
Departamento de Doen?as Infecciosas. Instituto Nacional de Sa?de Doutor Ricardo Jorge. Lisboa. Portugal.
Abstract
Introduction: Epidemiological surveillance of influenza, a disease associated with high mortality in the elderly and individuals' belongingto risk groups, is essential for the characterization of influenza epidemics as well as for the monitoring of outbreaks and the emergenceof viral strains resistant to antivirals.Material and Methods: In the present study was analyzed the influenza surveillance data from 2010/2011 winter. The clinical, epidemiologicaland virological data related to cases of flu-like syndrome have been collected through the National Influenza SurveillanceProgramme, coordinated by the National Influenza Reference Laboratory (LNRVG) in collaboration with the Department of Epidemiology(DEP) of the National Institute of Health Doutor Ricardo Jorge (INSA) and the Directorate-General for Health (DGS).Results: From the analysis of the data collected during the 2010/2011 winter season, influenza activity was moderate / high with anepidemic period of 8 weeks between week 50/2010 and 5 / 2011, with a peak of 121, 12 cases per 100 000 population in week 52/2010.Discussion: The influenza B viruses (Victoria lineage) predominated in the early period to week 1 / 2011, when became to predominateinfluenza A(H1)pdm09 viruses. The largest proportion of cases of influenza was found in the age group of children between 5 and 14years old. The viruses characterized antigenically and genetically were similar to strains included in the seasonal influenza vaccine2010/2011, presenting some amino acid substitutions in antigenic sites. Most strains of A(H1)pdm09 influenza virus still remain sensitiveto oseltamivir and zanamivir, although were detected sporadic cases of oseltamivir resistant viruses. To date, the LNRVG detectedthe presence of the H275Y substitution in the neuraminidase gene, associated with oseltamivir resistance, in three virus A(H1)pdm09.For one of them, oseltamivir resistance was confirmed by phenotypic assays.Conclusion: Despite fears associated with the emergence of a new pandemic virus (rapid spread, high morbidity and mortality), theclinical and epidemiological characteristics of infection with influenza A(H1)pdm09, proved in the course of two seasons (2009/2010and 2010/2011) to be very similar to seasonal flu. Is however noteworthy that during the pandemic season(2009/2010) the influenzavirus A (H1N1) pdm09 were linked with particular characteristics with regard to their temporal distribution, age groups most affected,severe infections and death and associated risk factors.
PMID:
23211197
[PubMed - in process]
http://www.ncbi.nlm.nih.gov/pubmed/23211197