A wave of influenza A (H1N1) 2009 was registered in the summer of 2009. We evaluated its repercussion on primary care consultations not diagnosed as influenza. We analysed primary care consultations in the Navarre Health Service from 21 June to 21 September 2009 with a diagnosis of influenza (International Classification of Primary Care, code R80), febrile syndrome (code A03), acute upper respiratory tract infection (code R74), or acute bronchitis (code R78); these consultations were then

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... ed with those occurring in the same period in the three previous years. In the summer of 2009, 3,417 cases of influenza syndrome (5.5 per 1000 population) were reported. An flu outbreak occurred between week 27 and 31, with over the mild (87/160) of swabs from patients with influenza syndrome positive for the virus A (H1N1), with no other influenza types detected. Coinciding with the wave of influenza syndromes, we observed increases in consultations for febrile syndrome and upper respiratory tract infection. In comparison with the mean for the three previous years, in the summer of 2009 consultations for febrile syndrome increased by 44% (3.6 to 5.3 per 1000; p<0.001), consultations for upper respiratory tract infection by 6% (13.2 to 14.1 per 1000; p<0.001), and consultations for bronchitis by 8% (6.3 to 6.9 per 1000; p<0.003). These diagnoses represented 3.2 additional consultations per 1000 population attributable to influenza, that is, 58% more consultations. Influenza gives rise to increased primary care consultations for influenza syndrome as well as for other less important processes.