Pandemin A/H1N1 2009 lindrigare än vanlig säsongsinfluensa. Rapport från Uppsala län
Sammanfattning
This descriptive analysis of influenza A (H1N1) 2009 was conducted in Uppsala County with approximately 330 000 inhabitants situated close to the Stockholm urban area. The pandemic influenza became a notifiable disease under the Swedish Communicable Diseases Act in May 2009, which implies that suspected influenza cases must be laboratory-verified and reported. The analysis was performed using the patient’s unique identification code via an electronic data based system (eCRF) complemented by the patient’s record. A total of 456 confirmed influenza cases were reported from June to the end of December. The main outbreak was restricted to five weeks in the autumn of 2009 when 82 % of the patients were reported. Thirty-five percent of the patients had underlying medical risk conditions. No difference in symptoms were found between patients with underlying medical conditions and patients without risk, whereas 64 % of the former received antiviral therapy compared to 24 % of the other patients. Patients with medical conditions received the vaccination in the beginning of the epidemic while patients without risk received the vaccination late. Forty-nine patients admitted vaccination, and of these 46 received the vaccination one week or less before onset of illness. The study showed that the clinical picture did not differ from seasonal influenza and that younger age groups were more affected whereas older persons had some protection. The pandemic based information from national and international authorities was not in proportion to the severity, extension or public welfare.