tetano
Editor, Senior Moderator
Int J Infect Dis
. 2023 May 16;S1201-9712(23)00566-0.
doi: 10.1016/j.ijid.2023.05.015. Online ahead of print. End-of-season influenza vaccine effectiveness during the Southern Hemisphere 2022 Influenza Season - Chile, Paraguay, and Uruguay
Anna N Chard[SUP] 1 [/SUP], Francisco Nogareda[SUP] 2 [/SUP], Annette K Regan[SUP] 3 [/SUP], María Fernanda Olivares Barraza[SUP] 4 [/SUP], Rodrigo A Fasce[SUP] 5 [/SUP], Natalia Vergara[SUP] 4 [/SUP], Marcela Avendaño[SUP] 4 [/SUP], Elena Penayo[SUP] 6 [/SUP], Cynthia Vázquez[SUP] 6 [/SUP], Marta Von Horoch[SUP] 6 [/SUP], Fabiana Michel[SUP] 7 [/SUP], Adriana Alfonso[SUP] 8 [/SUP], Cristina Mogdasy[SUP] 8 [/SUP], Hector Chiparelli[SUP] 8 [/SUP], Natalia Goñi[SUP] 8 [/SUP], Miguel Alegretti[SUP] 8 [/SUP], Sergio Loayza[SUP] 9 [/SUP], Paula Couto[SUP] 9 [/SUP], Angel Rodriguez[SUP] 9 [/SUP], Daniel Salas[SUP] 9 [/SUP], Ashley L Fowlkes[SUP] 10 [/SUP], Eduardo Azziz-Baumgartner[SUP] 10 [/SUP]
Affiliations
Objective: To estimate the 2022 end-of-season influenza vaccine effectiveness (VE) against severe acute respiratory illness (SARI) hospitalization in Chile, Paraguay, and Uruguay.
Methods: We pooled surveillance data from SARI cases in 18 sentinel surveillance hospitals in Chile (n=9), Paraguay (n=2), and Uruguay (n=7) during March 16-November 30, 2022. VE was estimated using a test-negative design and logistic regression models adjusted for country, age, sex, presence of ≥1 comorbidity, and week of illness onset. VE estimates were stratified by influenza virus type and subtype (when available) and influenza vaccine target population, categorized as children, individuals with comorbidities, and older adults, defined per countries' national immunization policies.
Results: Among the 3,147 SARI cases, there were 382 (12.1%) influenza test-positive case-patients; 328 (85.9%) influenza case-patients were in Chile, 33 (8.6%) were in Paraguay, and 21 (5.5%) were in Uruguay. In all countries, the predominant subtype was influenza A(H3N2) (92.6% of influenza cases). Adjusted VE against any influenza-associated SARI hospitalization was 33.8% (95% CI: 15.3%, 48.2%); VE against influenza A(H3N2)-associated SARI hospitalization was 30.4% (95% CI: 10.1%, 46.0%). VE estimates were similar across target populations.
Conclusion: During the 2022 influenza season, influenza vaccination reduced the odds of hospitalization among those vaccinated by one-third. Health officials should encourage influenza vaccination in accordance with national recommendations.
Keywords: epidemic; immunization; influenza; vaccine effectiveness.
. 2023 May 16;S1201-9712(23)00566-0.
doi: 10.1016/j.ijid.2023.05.015. Online ahead of print. End-of-season influenza vaccine effectiveness during the Southern Hemisphere 2022 Influenza Season - Chile, Paraguay, and Uruguay
Anna N Chard[SUP] 1 [/SUP], Francisco Nogareda[SUP] 2 [/SUP], Annette K Regan[SUP] 3 [/SUP], María Fernanda Olivares Barraza[SUP] 4 [/SUP], Rodrigo A Fasce[SUP] 5 [/SUP], Natalia Vergara[SUP] 4 [/SUP], Marcela Avendaño[SUP] 4 [/SUP], Elena Penayo[SUP] 6 [/SUP], Cynthia Vázquez[SUP] 6 [/SUP], Marta Von Horoch[SUP] 6 [/SUP], Fabiana Michel[SUP] 7 [/SUP], Adriana Alfonso[SUP] 8 [/SUP], Cristina Mogdasy[SUP] 8 [/SUP], Hector Chiparelli[SUP] 8 [/SUP], Natalia Goñi[SUP] 8 [/SUP], Miguel Alegretti[SUP] 8 [/SUP], Sergio Loayza[SUP] 9 [/SUP], Paula Couto[SUP] 9 [/SUP], Angel Rodriguez[SUP] 9 [/SUP], Daniel Salas[SUP] 9 [/SUP], Ashley L Fowlkes[SUP] 10 [/SUP], Eduardo Azziz-Baumgartner[SUP] 10 [/SUP]
Affiliations
- PMID: 37201863
- DOI: 10.1016/j.ijid.2023.05.015
Objective: To estimate the 2022 end-of-season influenza vaccine effectiveness (VE) against severe acute respiratory illness (SARI) hospitalization in Chile, Paraguay, and Uruguay.
Methods: We pooled surveillance data from SARI cases in 18 sentinel surveillance hospitals in Chile (n=9), Paraguay (n=2), and Uruguay (n=7) during March 16-November 30, 2022. VE was estimated using a test-negative design and logistic regression models adjusted for country, age, sex, presence of ≥1 comorbidity, and week of illness onset. VE estimates were stratified by influenza virus type and subtype (when available) and influenza vaccine target population, categorized as children, individuals with comorbidities, and older adults, defined per countries' national immunization policies.
Results: Among the 3,147 SARI cases, there were 382 (12.1%) influenza test-positive case-patients; 328 (85.9%) influenza case-patients were in Chile, 33 (8.6%) were in Paraguay, and 21 (5.5%) were in Uruguay. In all countries, the predominant subtype was influenza A(H3N2) (92.6% of influenza cases). Adjusted VE against any influenza-associated SARI hospitalization was 33.8% (95% CI: 15.3%, 48.2%); VE against influenza A(H3N2)-associated SARI hospitalization was 30.4% (95% CI: 10.1%, 46.0%). VE estimates were similar across target populations.
Conclusion: During the 2022 influenza season, influenza vaccination reduced the odds of hospitalization among those vaccinated by one-third. Health officials should encourage influenza vaccination in accordance with national recommendations.
Keywords: epidemic; immunization; influenza; vaccine effectiveness.