[Influenza (H1N1) 2009 in Castilla y Leon, Spain: hospitalized case studies and match with the protocols of action developed].

Background: In April 2009, the World Health Organization declared the emergence of human cases by a new influenza virus H1N1 as a Public Health Emergency of International Importance. Our objective was to analyze the characteristics of the cases investigated and to assess the compliance of the subjects studied with the indications and recommendations of the Health Regional Ministry of Health Castilla y León.

Methods: A descriptive epidemiological study of all positive cases and every requests made to Castilla y León, from epidemiological weeks 44 to 50, both included.

Results: 588 requests were made to test for influenza A H1N1 (58% males). The mean age was 34.8 years (27.1% between 15 and 44 years). 42% fulfilled criteria for severity. Chronic respiratory disease was the most common risk factor found (18.9%). Antiviral treatment was found in 19.1% (54.5% within the first 48 hours). 27.4% of the requests were positive (53.4% males). The mean age of the positive cases was 34.52 years was positive (33.1% between 15 and 44 years). 47.8% of them fulfilled criteria for severity and chronic respiratory disease was also the most common risk factor found also in the positive (26.7%). Only 6.8% were morbidly obese. 28.9% of positives received antiviral treatment (61.4% within the first 48 hours).

Conclusion: Most cases did not fulfil severity criteria, which illustrates the low compliance of monitoring protocols in sanitary care system.