[Self-reported cases of influenza among Spanish healthcare workers during the 2009 influenza A(H1N1) pandemic]

Abstract

Objectives: To describe the prevalence of influenza-like syndrome in winter 2009 and the factors associated with its occurrence.

Methods: A cross-sectional study was carried out in 18 hospitals in Spain. Volunteers completed a health questionnaire in which they reported the occurrence of influenza-like syndrome and vaccination and demographic status.

Results: A total of 1,289 healthcare workers participated. Of these, 72 (5.6%) reported influenza in their family, 195 (15.1%) had been vaccinated against the A/California/7/2009/H1N1 virus and 75 (5.8%, 95%CI: 4.5-7.1%) had been diagnosed with influenza like-syndrome. There were differences among regions. In logistic regression analysis, the following factors were associated with a higher prevalence of influenza-like syndrome: working in Madrid (OR=8.31, 95%CI: 1.05-65.39), the occurrence of cases of influenza in the family (OR=2.84, 95%CI: 1.41-5.73) and not having been vaccinated against influenza A (H1N1) (OR=2.68, 95% CI: 1.05-6.82).

Conclusions: Differences in the prevalence of influenza-like syndrome were due to the occurrence of familiar cases and region. Vaccination against influenza A (H1N1) was associated with a lower prevalence of the disease.