TY - JOUR
T1 - Moderate influenza vaccine effectiveness against A(H1N1)pdm09 virus, and low effectiveness against A(H3N2) subtype, 2018/19 season in Italy.
AU - Tramuto, Fabio
AU - Pariani, Elena
AU - Facchini, Marzia
AU - Calzoletti, Laura
AU - Tiberti, Donatella
AU - Di Martino, Angela
AU - Bellino, Stefania
AU - Gallo, Tolinda
AU - Pagani, Elisabetta
AU - Di Mario, Giuseppina
AU - Romano, Lucio
AU - Tosti, Anna
AU - Natter, Bernhard
AU - Senatore, Sabrina
AU - Volpe, Enrico
AU - D’Agaro, Pierlanfranco
AU - Punzo, Ornella
AU - Puzelli, Simona
AU - Pascucci, Maria Grazia
AU - Rita Tanchis, Pierina
AU - Di Carlo, Vittorio
AU - Pagani, Elisabetta
AU - Affanni, Paola
AU - Giannecchini, Simone
AU - Chironna, Maria
AU - Fabiani, Concetta
AU - Ghisetti, Valeria
AU - Germinario, Cinzia
AU - Bella, Antonino
AU - Pezzotti, Patrizio
AU - Castrucci, Maria Rita
AU - Serra, Caterina
AU - Camilloni, Barbara
PY - 2019
Y1 - 2019
N2 - Background: Influenza vaccines are updated every year to match the vaccine strains with currently circulating viruses; consequently influenza vaccine effectiveness (IVE) has to be assessed annually.Research design and methods: A test-negative case-control study was conducted within the context of the Italian sentinel influenza surveillance network to estimate IVE by age group, virus subtype, and vaccine brand in medically attended laboratory-confirmed influenza.Results: In Italy, the 2018/19 influenza season was characterized by the co-circulation of influenza A(H1N1)pdm09 and A(H3N2) viruses. The adjusted IVE estimate in preventing influenza was moderate (44.8%, 95% CI: 18.8 to 62.5) against A(H1N1)pdm09, whereas there was no evidence of effectiveness (1.8%, 95% CI: -37.8 to 30.1) in persons affected by A(H3N2). IVE against A(H1N1)pdm09 decreased with age ranging from 65.7% to 13.1% among children/adolescents and elderly, respectively; moreover results suggest that Vaxigrip Tetra® was more effective against A(H1N1)pdm09 compared to Fluarix Tetra® [62.5% (95% CI: 34.3 to 78.6) vs 24.5% (95% CI: -40.6 to 59.6)]. Low effectiveness (35.2%, 95% CI: -50.8 to 72.1) against A(H3N2) was detected only in the elderly immunized with Fluad®.Conclusions: Findings suggest that influenza vaccines were low to moderately effective, probably due to a mismatch between circulating and vaccine strains.
AB - Background: Influenza vaccines are updated every year to match the vaccine strains with currently circulating viruses; consequently influenza vaccine effectiveness (IVE) has to be assessed annually.Research design and methods: A test-negative case-control study was conducted within the context of the Italian sentinel influenza surveillance network to estimate IVE by age group, virus subtype, and vaccine brand in medically attended laboratory-confirmed influenza.Results: In Italy, the 2018/19 influenza season was characterized by the co-circulation of influenza A(H1N1)pdm09 and A(H3N2) viruses. The adjusted IVE estimate in preventing influenza was moderate (44.8%, 95% CI: 18.8 to 62.5) against A(H1N1)pdm09, whereas there was no evidence of effectiveness (1.8%, 95% CI: -37.8 to 30.1) in persons affected by A(H3N2). IVE against A(H1N1)pdm09 decreased with age ranging from 65.7% to 13.1% among children/adolescents and elderly, respectively; moreover results suggest that Vaxigrip Tetra® was more effective against A(H1N1)pdm09 compared to Fluarix Tetra® [62.5% (95% CI: 34.3 to 78.6) vs 24.5% (95% CI: -40.6 to 59.6)]. Low effectiveness (35.2%, 95% CI: -50.8 to 72.1) against A(H3N2) was detected only in the elderly immunized with Fluad®.Conclusions: Findings suggest that influenza vaccines were low to moderately effective, probably due to a mismatch between circulating and vaccine strains.
UR - http://hdl.handle.net/10447/417591
M3 - Article
VL - 18
SP - 1201
EP - 1209
JO - Expert Review of Vaccines
JF - Expert Review of Vaccines
SN - 1476-0584
ER -