Influenza Vaccination in Italian Healthcare Workers (2018–2019 Season): Strengths and Weaknesses. Results of a Cohort Study in Two Large Italian Hospitals
Background: Annual vaccination is the most effective way to combat influenza. As influenza viruses evolve, seasonal vaccines are updated annually. Within the European project Development of Robust and Innovative Vaccine Effectiveness (DRIVE), a cohort study involving Italian healthcare workers (HCWs...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-03-01
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| Series: | Vaccines |
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| Online Access: | https://www.mdpi.com/2076-393X/8/1/119 |
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| author | Donatella Panatto Piero Luigi Lai Stefano Mosca Elvina Lecini Andrea Orsi Alessio Signori Silvana Castaldi Elena Pariani Laura Pellegrinelli Cristina Galli Giovanni Anselmi Giancarlo Icardi CIRI-IT Team |
| author_facet | Donatella Panatto Piero Luigi Lai Stefano Mosca Elvina Lecini Andrea Orsi Alessio Signori Silvana Castaldi Elena Pariani Laura Pellegrinelli Cristina Galli Giovanni Anselmi Giancarlo Icardi CIRI-IT Team |
| author_sort | Donatella Panatto |
| collection | DOAJ |
| description | Background: Annual vaccination is the most effective way to combat influenza. As influenza viruses evolve, seasonal vaccines are updated annually. Within the European project Development of Robust and Innovative Vaccine Effectiveness (DRIVE), a cohort study involving Italian healthcare workers (HCWs) was carried out during the 2018-2019 season. Two aims were defined: to measure influenza vaccine effectiveness (IVE) against laboratory-confirmed influenza cases and to conduct an awareness-raising campaign to increase vaccination coverage. Methods: Each subject enrolled was followed up from enrollment to the end of the study. Each HCW who developed ILI was swabbed for laboratory confirmation of influenza. Influenza viruses were identified by molecular assays. A Cox regression analysis, crude and adjusted for confounding variables, was performed to estimate the IVE. Results: Among the 4483 HCWs enrolled, vaccination coverage was 32.5%, and 308 ILI cases were collected: 23.4% were positive for influenza (54.2% A(H1N1) pdm09; 45.8% A(H3N2)). No influenza B viruses were detected. No overall IVE was observed. Analyzing the subtypes of influenza A viruses, the IVE was estimated as 45% (95% CI: -59 to 81) for A(H1N1) pdm09. Conclusions: Vaccination coverage among HCWs increased. Study difficulties and the circulation of drifted variants of A(H3N2) could partly explain the observed IVE. |
| first_indexed | 2024-04-11T22:13:47Z |
| format | Article |
| id | doaj.art-8c9b23c2dfc44d2ba75d0b1a69feafec |
| institution | Directory Open Access Journal |
| issn | 2076-393X |
| language | English |
| last_indexed | 2024-04-11T22:13:47Z |
| publishDate | 2020-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Vaccines |
| spelling | doaj.art-8c9b23c2dfc44d2ba75d0b1a69feafec2022-12-22T04:00:28ZengMDPI AGVaccines2076-393X2020-03-018111910.3390/vaccines8010119vaccines8010119Influenza Vaccination in Italian Healthcare Workers (2018–2019 Season): Strengths and Weaknesses. Results of a Cohort Study in Two Large Italian HospitalsDonatella Panatto0Piero Luigi Lai1Stefano Mosca2Elvina Lecini3Andrea Orsi4Alessio Signori5Silvana Castaldi6Elena Pariani7Laura Pellegrinelli8Cristina Galli9Giovanni Anselmi10Giancarlo Icardi11CIRI-IT Team12Department of Health Sciences, University of Genoa, Via Pastore 1, 16132 Genoa, ItalyDepartment of Health Sciences, University of Genoa, Via Pastore 1, 16132 Genoa, ItalyInteruniversity Research Center on Influenza and Other Transmissible Infections (CIRI-IT), Via Pastore 1, 16132 Genoa, ItalyDepartment of Health Sciences, University of Genoa, Via Pastore 1, 16132 Genoa, ItalyDepartment of Health Sciences, University of Genoa, Via Pastore 1, 16132 Genoa, ItalyDepartment of Health Sciences, University of Genoa, Via Pastore 1, 16132 Genoa, ItalyDepartment of Biomedical Sciences for Health, University of Milan, Via C. Pascal 36, 20133 Milano, ItalyInteruniversity Research Center on Influenza and Other Transmissible Infections (CIRI-IT), Via Pastore 1, 16132 Genoa, ItalyDepartment of Biomedical Sciences for Health, University of Milan, Via C. Pascal 36, 20133 Milano, ItalyDepartment of Biomedical Sciences for Health, University of Milan, Via C. Pascal 36, 20133 Milano, ItalyDepartment of Biomedical Sciences for Health, University of Milan, Via C. Pascal 36, 20133 Milano, ItalyDepartment of Health Sciences, University of Genoa, Via Pastore 1, 16132 Genoa, ItalyDepartment of Health Sciences, University of Genoa, Via Pastore 1, 16132 Genoa, ItalyBackground: Annual vaccination is the most effective way to combat influenza. As influenza viruses evolve, seasonal vaccines are updated annually. Within the European project Development of Robust and Innovative Vaccine Effectiveness (DRIVE), a cohort study involving Italian healthcare workers (HCWs) was carried out during the 2018-2019 season. Two aims were defined: to measure influenza vaccine effectiveness (IVE) against laboratory-confirmed influenza cases and to conduct an awareness-raising campaign to increase vaccination coverage. Methods: Each subject enrolled was followed up from enrollment to the end of the study. Each HCW who developed ILI was swabbed for laboratory confirmation of influenza. Influenza viruses were identified by molecular assays. A Cox regression analysis, crude and adjusted for confounding variables, was performed to estimate the IVE. Results: Among the 4483 HCWs enrolled, vaccination coverage was 32.5%, and 308 ILI cases were collected: 23.4% were positive for influenza (54.2% A(H1N1) pdm09; 45.8% A(H3N2)). No influenza B viruses were detected. No overall IVE was observed. Analyzing the subtypes of influenza A viruses, the IVE was estimated as 45% (95% CI: -59 to 81) for A(H1N1) pdm09. Conclusions: Vaccination coverage among HCWs increased. Study difficulties and the circulation of drifted variants of A(H3N2) could partly explain the observed IVE.https://www.mdpi.com/2076-393X/8/1/119influenzainfluenza vaccinationhealthcare workerslaboratory-confirmed influenzainfluenza vaccination coverage |
| spellingShingle | Donatella Panatto Piero Luigi Lai Stefano Mosca Elvina Lecini Andrea Orsi Alessio Signori Silvana Castaldi Elena Pariani Laura Pellegrinelli Cristina Galli Giovanni Anselmi Giancarlo Icardi CIRI-IT Team Influenza Vaccination in Italian Healthcare Workers (2018–2019 Season): Strengths and Weaknesses. Results of a Cohort Study in Two Large Italian Hospitals Vaccines influenza influenza vaccination healthcare workers laboratory-confirmed influenza influenza vaccination coverage |
| title | Influenza Vaccination in Italian Healthcare Workers (2018–2019 Season): Strengths and Weaknesses. Results of a Cohort Study in Two Large Italian Hospitals |
| title_full | Influenza Vaccination in Italian Healthcare Workers (2018–2019 Season): Strengths and Weaknesses. Results of a Cohort Study in Two Large Italian Hospitals |
| title_fullStr | Influenza Vaccination in Italian Healthcare Workers (2018–2019 Season): Strengths and Weaknesses. Results of a Cohort Study in Two Large Italian Hospitals |
| title_full_unstemmed | Influenza Vaccination in Italian Healthcare Workers (2018–2019 Season): Strengths and Weaknesses. Results of a Cohort Study in Two Large Italian Hospitals |
| title_short | Influenza Vaccination in Italian Healthcare Workers (2018–2019 Season): Strengths and Weaknesses. Results of a Cohort Study in Two Large Italian Hospitals |
| title_sort | influenza vaccination in italian healthcare workers 2018 2019 season strengths and weaknesses results of a cohort study in two large italian hospitals |
| topic | influenza influenza vaccination healthcare workers laboratory-confirmed influenza influenza vaccination coverage |
| url | https://www.mdpi.com/2076-393X/8/1/119 |
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