Análisis de la temporada gripal 2017-2018, predominio del linaje Yamagata de la gripe B en los adultos

Introduction: The epidemiological and virological characteristics of the 2017-2018 flu season in its aspects of mortality and age groups are analyzed. Patients and method: Respiratory samples from both the Sentinel Influenza Surveillance Network and patients treated in the emergency room and hospitalized in our center were subjected to the detection of respiratory viruses using a commercial genomic amplification technique, type RT- PCR (Allplex Respiratory Panel, Seegen, North Korea), which identifies 16 different respiratory viruses simultaneously and differentially. Among them influenza viruses A (H1N1) pdm09 and A (H3N2) and influenza virus type B, although no difference between their two lineages. Results: During the flu season, 6,465 respiratory samples were analyzed, of which 3,228 (49.9%) were considered positive (detection of a respiratory virus). Of these, in 1232 a flu virus was detected, representing 19% of all processed samples and 38.2% of all positive samples. Of all the influenza viruses detected, 661 (53.6%) were identified as influenza A and 571 (46.4%) influenza B. The RCVG contributed 127 (10.3%) positive samples, 58 (8.7%) group A and 69 (12%) Influenza B. The rest of the positive samples, 1,105 (89.7%), came from the hospital setting, that is, 603 (91.3%) were influenza A and 502 (88%) were influenza B. Regarding the subtypes of influenza A, They detected 415 (62.7%) cases of the subtype A (H1N1) pdm09, 38 (9.1%) of the RCVG and 377 (90.9%) of the hospital setting. Subtype A (H3N2) detected 246 (37.3%) cases, of which 20 (8.1%) belonged to the RCVG and 226 (91.9%) to the hospital setting. When analyzing the subtypes on the total samples of each provenance, it is verified that of the 58 cases of influenza A belonging to the RCVG 38 (65.5%) were A (H1N1) pdm09 and 20 (34.5%) A (H3N2). In the hospital setting, of the 603 cases of influenza A, 377 (62.5%) were A (H1N1) pdm09 and 226 (37.5%) were A (H3N2), no significant differences were observed. Conclusions: The 2017-2018 flu season should be considered as an atypical season in which the co-circulation of the four flu types / subtypes determined the highest epidemiological rate and the highest number of cases registered in the Balearic Islands. Introducción: Se analizan las características epidemiológicas y virológicas de la temporada gripal 2017-2018 en sus aspectos de mortalidad y grupos etários. Pacientes y método: Las muestras respiratorias proceden tanto de la Red Centinela de Vigila