Influenza virus infections from 0 to 2 years of age: A birth cohort study
Background/purpose: Influenza vaccine has been recommended in Finland since 2007 for all children of 6–35 months of age and in 2009 for those ≥6 months against pandemic influenza. We investigated the incidence of influenza and vaccine effectiveness in a birth cohort of children in 2008–2011. Methods...
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| Format: | Article |
| Language: | English |
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Elsevier
2019-08-01
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| Series: | Journal of Microbiology, Immunology and Infection |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S168411821730258X |
| _version_ | 1818215270725976064 |
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| author | Tamara Teros-Jaakkola Laura Toivonen Linnea Schuez-Havupalo Sinikka Karppinen Ilkka Julkunen Matti Waris Ville Peltola |
| author_facet | Tamara Teros-Jaakkola Laura Toivonen Linnea Schuez-Havupalo Sinikka Karppinen Ilkka Julkunen Matti Waris Ville Peltola |
| author_sort | Tamara Teros-Jaakkola |
| collection | DOAJ |
| description | Background/purpose: Influenza vaccine has been recommended in Finland since 2007 for all children of 6–35 months of age and in 2009 for those ≥6 months against pandemic influenza. We investigated the incidence of influenza and vaccine effectiveness in a birth cohort of children in 2008–2011. Methods: We followed 923 children from birth to 2 years of age for respiratory tract infections. A nasal swab sample for PCR for influenza A and B viruses was taken at the onset of acute respiratory infections. Samples were collected either at the study clinic or at home by parents. Vaccination data was retrieved from the health registries. Results: Vaccination coverage of children aged 6–23 months was 22–47% against seasonal influenza and 80% against the A(H1N1)pdm09 virus in the pandemic season 2009–2010. During 3 influenza seasons, 1607 nasal swab samples were collected. Influenza was confirmed in 56 (6.1%) of 923 children (16 A(H1N1), 14 A(H3N2), and 26 B viruses). The incidence of influenza was 5.1% in 2008–2009, 2.7% in 2009–2010, and 5.0% in 2010–2011. Effectiveness of the adjuvanted vaccine against the pandemic influenza A(H1N1)pdm09 was 97% (95% confidence interval, 76–100%). Three children with influenza were hospitalized. Conclusion: The yearly incidence of seasonal influenza was 5% in this cohort of very young children with variable influenza vaccine coverage. Adjuvanted vaccine against the pandemic influenza was highly effective. Both seasonal and pandemic influenza cases were mostly non-severe. Keywords: Children, Infant, Influenza, Pandemic influenza, Vaccination, Vaccine-preventable diseases |
| first_indexed | 2024-12-12T06:33:25Z |
| format | Article |
| id | doaj.art-c385921989cc4b67928293d278109baf |
| institution | Directory Open Access Journal |
| issn | 1684-1182 |
| language | English |
| last_indexed | 2024-12-12T06:33:25Z |
| publishDate | 2019-08-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Microbiology, Immunology and Infection |
| spelling | doaj.art-c385921989cc4b67928293d278109baf2022-12-22T00:34:32ZengElsevierJournal of Microbiology, Immunology and Infection1684-11822019-08-01524526533Influenza virus infections from 0 to 2 years of age: A birth cohort studyTamara Teros-Jaakkola0Laura Toivonen1Linnea Schuez-Havupalo2Sinikka Karppinen3Ilkka Julkunen4Matti Waris5Ville Peltola6Department of Paediatrics and Adolescent Medicine, Turku University Hospital and University of Turku, Turku, FinlandDepartment of Paediatrics and Adolescent Medicine, Turku University Hospital and University of Turku, Turku, FinlandDepartment of Paediatrics and Adolescent Medicine, Turku University Hospital and University of Turku, Turku, FinlandDepartment of Paediatrics and Adolescent Medicine, Turku University Hospital and University of Turku, Turku, FinlandDepartment of Virology, University of Turku, Turku, FinlandDepartment of Virology, University of Turku, Turku, FinlandDepartment of Paediatrics and Adolescent Medicine, Turku University Hospital and University of Turku, Turku, Finland; Corresponding author. Department of Paediatrics and Adolescent Medicine, Turku University Hospital, 20521, Turku, Finland. Fax: +358 2 3131460.Background/purpose: Influenza vaccine has been recommended in Finland since 2007 for all children of 6–35 months of age and in 2009 for those ≥6 months against pandemic influenza. We investigated the incidence of influenza and vaccine effectiveness in a birth cohort of children in 2008–2011. Methods: We followed 923 children from birth to 2 years of age for respiratory tract infections. A nasal swab sample for PCR for influenza A and B viruses was taken at the onset of acute respiratory infections. Samples were collected either at the study clinic or at home by parents. Vaccination data was retrieved from the health registries. Results: Vaccination coverage of children aged 6–23 months was 22–47% against seasonal influenza and 80% against the A(H1N1)pdm09 virus in the pandemic season 2009–2010. During 3 influenza seasons, 1607 nasal swab samples were collected. Influenza was confirmed in 56 (6.1%) of 923 children (16 A(H1N1), 14 A(H3N2), and 26 B viruses). The incidence of influenza was 5.1% in 2008–2009, 2.7% in 2009–2010, and 5.0% in 2010–2011. Effectiveness of the adjuvanted vaccine against the pandemic influenza A(H1N1)pdm09 was 97% (95% confidence interval, 76–100%). Three children with influenza were hospitalized. Conclusion: The yearly incidence of seasonal influenza was 5% in this cohort of very young children with variable influenza vaccine coverage. Adjuvanted vaccine against the pandemic influenza was highly effective. Both seasonal and pandemic influenza cases were mostly non-severe. Keywords: Children, Infant, Influenza, Pandemic influenza, Vaccination, Vaccine-preventable diseaseshttp://www.sciencedirect.com/science/article/pii/S168411821730258X |
| spellingShingle | Tamara Teros-Jaakkola Laura Toivonen Linnea Schuez-Havupalo Sinikka Karppinen Ilkka Julkunen Matti Waris Ville Peltola Influenza virus infections from 0 to 2 years of age: A birth cohort study Journal of Microbiology, Immunology and Infection |
| title | Influenza virus infections from 0 to 2 years of age: A birth cohort study |
| title_full | Influenza virus infections from 0 to 2 years of age: A birth cohort study |
| title_fullStr | Influenza virus infections from 0 to 2 years of age: A birth cohort study |
| title_full_unstemmed | Influenza virus infections from 0 to 2 years of age: A birth cohort study |
| title_short | Influenza virus infections from 0 to 2 years of age: A birth cohort study |
| title_sort | influenza virus infections from 0 to 2 years of age a birth cohort study |
| url | http://www.sciencedirect.com/science/article/pii/S168411821730258X |
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