Descriptive study of severe hospitalized cases of laboratory-confirmed influenza during five epidemic seasons (2010–2015)

Abstract

ObjectiveThe Plan of Information on Acute Respiratory Infections in Catalonia (PIDIRAC) included the surveillance of severe hospitalized cases of laboratory-confirmed influenza (SHCLCI) in 2009. The objective of this study was to determine the clinical, epidemiological and virological features of SHCLCI recorded in 12 sentinel hospitals during five influenza seasons.ResultsFrom a sample of SHCLCI recorded during the 5 influenza epidemics seasons from 2010–2011 to 2014–2015, Cases were confirmed by PCR and/or viral isolation in cell cultures from respiratory samples. A total of 1400 SHCLCI were recorded, 33% required ICU admission and 12% died. The median age of cases was 61 years (range 0–101 years); 70.5% were unvaccinated; 80.4% received antiviral treatment (in 79.6 and 24% of cases within 48 h after hospital admission and the onset of symptoms, respectively); influenza virus A [37.9% A (H1N1)pdm09, 29.3% A (H3N2)] was identified in 87.7% of cases. Surveillance of SHCLCI provides an estimate of the severity of seasonal influenza epidemics and the identification and characterization of at-risk groups in order to facilitate preventive measures such as vaccination and early antiviral treatment.Electronic supplementary materialThe online version of this article (10.1186/s13104-018-3349-y) contains supplementary material, which is available to authorized users.

Influenza Virus Subtyping by Multiplex PCR during Winter Months of 2017-2018

“…Moreover, starting antivirals as soon as possible, especially within 48 hours of onset of symptoms, will help reduce disease severity and loss of function. 19…”

Surveillance Data for Eight Consecutive Influenza Seasons in Sicily, Italy

“…Torner et al, 8 in Catalonia, displayed a similar picture among severe hospitalized cases during five post-pandemic seasons (2010-2015), although the authors hypothesized a bias explained by a greater prevalence of influenza A viruses spread in the population during the observed period.…”

“…4,5 Elderly population, defined as those aged 65 years and older, and, more specifically, elderly people with underlying conditions, are at increased risk for hospitalization and death, also in industrialized countries. [6][7][8] The best strategy to prevent influenza is vaccination, the effectiveness of which strongly depends on the variability of circulating viruses, representing a major challenge for public health systems worldwide. 9 Therefore, it is of paramount importance a continuous monitoring of genetic and antigenic features of influenza strains.…”

Effectiveness of Influenza Vaccination in Hospitalized Cases in Catalonia During the 2017-2018 Season

“…Yet some subsets of population are at higher risk for more severe disease which may require hospitalization and/or intensive care unit admission due to complications such as pneumonia or acute respiratory distress. It is well known that the elderly (≥65 years of age) have the highest risk of increased morbidity including respiratory failure, and mortality; It is estimated that over 60% of all seasonal-influenza-related hospitalizations and 90% of seasonal-influenza-related deaths each year occur in the elderly [2,[3][4][5][6][7] in Europe [9], suggest that vaccination offered only slight protection for severe outcome due to this fact and because there was a high proportion of elderly hospitalizations (79.1%) and that older age is associated with a lower ICU admission [10].Data on the inverse relation between age and ICU admission has also been pointed out by other authors who found higher rate of ICU admission among SHCIC at 15-64 y [11][12][13][14].…”

“…Figure 1. Laboratory confirmation was carried out by Polymerase Chain reaction (PCR) and/or culture techniques on nasal aspirate or nasopharyngeal swab sampling described in previous publications [4,6,7]. All hospitalized cases were followed up until discharge to determine the disease progression and outcome.…”