Clinical and epidemiological characteristics of hospitalized patients with pandemic A(H1N1) 2009 influenza

Abstract

Pandemijski virus influence A (H1N1) 2009 u nas se pojavio u srpnju, intenzivniji val bolesti zabilježen je u listopadu, studenome i prosincu 2009. godine, a bolest se pojavljivala sve do ožujka 2010. godine. U Hrvatskoj je registrirano 58 255 oboljelih od pandemijske gripe, a umrlo ih je 58, od toga 32 s laboratorijski dokazanim virusom. U razdoblju od 1. srpnja 2009. do 31. ožujka 2010. godine u Klinici za infektivne bolesti "Dr. Fran Mihaljević" u Zagrebu pregledano je 3 856 bolesnika s dijagnozom influence i/ili komplikacija. Od toga broja hospitalizirana su 562 (14,6 %) bolesnika. Od ukupnog broja hospitaliziranih, djece do 14 godina bilo je 140 (24,9 %), do 18 godina 154 (27,4 %), a odraslih gotovo triput više, odnosno 408 (72,6 %). U jedinicama intenzivne skrbi liječeno je 68 (12,1 %) bolesnika. Umrlo je 15 odraslih bolesnika, od kojih je 14 liječeno u jedinici intenzivnog liječenja. Stopa smrtnosti za sve hospitalizirane bolesnike (562) iznosi 2,7 %, za hospitalizirane odrasle (408) 3,7 %, a za odrasle liječene u jedinici intenzivne skrbi 26,4 %. Nije umrlo niti jedno dijete. Od 562 hospitalizirana bolesnika, virus pandemijske influence A(H1N1) 2009 dokazan je PCR metodom u njih 169 (30,1 %). Pandemijski virus influence otkriven je u 41,6 % hospitalizirane djece i u 25,7 % odraslih. U jedinicama intenzivne skrbi s dokazanim virusom liječeno je 35 (20,7 %) bolesnika, 22 odrasla i 13 djece. Prosječna dob svih bolesnika s dokazanim pandemijskim virusom (169) iznosila je 30,2 godina. U dječjoj skupini prosječna je dob bila 5,6 godina, a kod odraslih 45,2 godina. U odnosu na odrasle, djeca su prije dolazila i imala su znatno kraći boravak u bolnici, a u njih su zabilježene statistički značajno niže vrijednosti CRP-a, CK i sedimentacije eritrocita. U 169 bolesnika s dokazanim pandemijskim virusom influence ukupno je registrirano 227 rizičnih čimbenika, a zabilježeni su kod 95 (56,2 %) bolesnika. U odraslih su rizični imbenici zabilježeni znatno češće i u većem broju nego u djece. Najučestaliji rizični čimbenici bile su kronične plućne bolesti: astma u 29 (17,2 %) bolesnika i kronična opstruktivna plućna bolest (KOPB) u 27 (15,9 %) bolesnika. Registrirano je 240 komplikacija bolesti u 117 (69,2 %) bolesnika. Komplikacije su se češće pojavljivale i prosječno su bile teže u odraslih nego u djece. Pneumonija je bila najučestalija komplikacija, a registrirana je u 84/169 bolesnika, odnosno u svakog drugog hospitaliziranog bolesnika s dokazanim virusom pandemijske influence. Pneumonija je bila mnogo češća komplikacija u odraslih (66/105 ili 62,9 %) nego u djece (18/64 ili 28,1 %). Primarna virusna pneumonija registrirana je dvaput češće od sekundarne bakterijske (55:29 bolesnika). Zbog pandemijske influence 2009/10. godine hospitalizirano je 2,7 puta više odraslih nego djece (408:154), za razliku od deset prethodnih sezona influence kada su djeca bila 1,2 puta češće hospitalizirana od odraslih (759:656). Nameće se zaključak da je pandemijska influenca bila znatno teža i smrtonosnija bolest u usporedbi sa sezonskom, posebno u dobnim skupinama mlađih odraslih ljudi, iako pandemijom nije bio zahvaćen veći postotak pučanstva.Pandemic influenza A (H1N1) 2009 virus was first recorded in Croatia in July, and a more intense wave was recorded in October, November and December 2009, with the disease occurring throughout March 2010. Atotal of 58.255 pandemic influenza cases were recorded in Croatia, with 58 deaths, of whom 32 patients with laboratory confirmed virus. In the period from July 1, 2009 until March 31, 2010, a total of 3.856 patients with diagnosed influenza and/or complications were examined at the University Hospital for Infectious Diseases "Dr Fran Mihaljevic", Zagreb. Altogether 562 (14,6 %) patients were hospitalized, of whom 140 (24,9 %) children under 14 years of age, 154 (27,4 %) children aged between 14–18 years, with three times more adults hospitalized – 408 (72,6 %) in total. Atotal of 68 (12,1 %) patients were treated at intensive care unit (ICU). Fifteen adult patients died, of whom 14 treated in ICU. The mortality rate for all 562 hospitalized patients was 2,7 %, for 408 hospitalized adults 3,7 %, and for adults treated in ICU 26,4 %. No deaths were recorded among children. Out of 562 hospitalized patients, pandemic influenza A (H1N1) 2009 virus was detected by PCR method in 169 (30,1 %) patients. Pandemic influenza virus was detected in 41,6 % of hospitalized children and in 25,7 % of adults. In total, 35 (20,7 %) patients with confirmed virus were treated in ICU (22 adults and 13 children). The average age of all 169 patients with confirmed pandemic virus was 30,2 years. The average age of children was 5,6 years, and of adults 45,2 years. Compared to adults, children reported to hospital sooner and had a significantly shorter hospital stay, with recorded statistically significant lower values of CRP, CK and erythrocyte sedimentation rate. Out of 169 cases with confirmed pandemic influenza virus, altogether 227 risk factors were recorded in 95 (56,2 %) patients. Risk factors were more frequent and more numerous in adults than in children. The most commonly recorded risk factors were chronic pulmonary diseases – asthma in 29 patients (17,2 %) and chronic obstructive pulmonary disease (COPD) in 27 (15,9 %). We also recorded 240 disease complications in 117 (69,2 %) patients. Complications were more common and, on average, more severe in adults than in children. Pneumonia was the most frequent complication, and was recorded in 84/169 patients, i.e. in every second hospitalized patient with confirmed pandemic influenza virus. Pneumonia was more frequent complication in adults (66/105 or 62,9 %) than in children (18/64 or 28,1 %). Primary viral pneumonia was twice more frequent than secondary bacterial (55:29 patients). Due to pandemic 2009/10 influenza, 2,7 times more adults than children were hospitalized (408:154), while in ten previous influenza seasons, children were 1,2 times more often hospitalized than adults (759:656). Aconclusion is imposed that pandemic influenza was more severe and lethal disease compared to seasonal influenza, especially among younger adults, although the pandemic did not affect a higher percentage of the population