tetano
Editor, Senior Moderator
Paediatr Drugs. 2016 Jun 7. [Epub ahead of print]
[h=1]Estimates of the Public Health Impact of a Pediatric Vaccination Program Using an Intranasal Tetravalent Live-Attenuated Influenza Vaccine in Belgium.[/h] Gerlier L[SUP]1[/SUP], Lamotte M[SUP]2[/SUP], Dos Santos Mendes S[SUP]3[/SUP], Damm O[SUP]4[/SUP], Schwehm M[SUP]5[/SUP], Eichner M[SUP]6,[/SUP][SUP]7[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]OBJECTIVES:[/h] Our objectives were to estimate the public health outcomes of vaccinating Belgian children using an intranasal tetravalent live-attenuated influenza vaccine (QLAIV) combined with current coverage of high-risk/elderly individuals using the trivalent inactivated vaccine.
[h=4]METHODS:[/h] We used a deterministic, age-structured, dynamic model to simulate seasonal influenza transmission in the Belgian population under the current coverage or after extending vaccination with QLAIV to healthy children aged 2-17 years. Differential equations describe demographic changes, exposure to infectious individuals, infection recovery, and immunity dynamics. The basic reproduction number (R [SUB]0[/SUB]) was calibrated to the observed number of influenza doctor visits/year. Vaccine efficacy was 80 % (live-attenuated) and 59-68 % (inactivated). The 10-year incidence of symptomatic influenza was calculated with different coverage scenarios (add-on to current coverage).
[h=4]RESULTS:[/h] Model calibration yielded R [SUB]0[/SUB] = 1.1. QLAIV coverage of 75 % of those aged 2-17 years averted 374,000 symptomatic cases/year (57 % of the current number), 244,000 of which were among adults (indirect effect). Vaccinating 75 % of those aged 2-11 years and 50 % of those aged 12-17 years averted 333,200 cases/year (213,000 adult cases/year). Vaccinating only healthy children aged 2-5 years generated direct protection but limited indirect protection, even with 90 % coverage (40,800 averted adult cases/year; -8.4 %). Targeting all children averted twice as many high-risk cases as targeting high-risk children only (8485 vs. 4965/year with 75 % coverage). Sensitivity analyses showed the robustness of results.
[h=4]CONCLUSIONS:[/h] The model highlights the direct and indirect protection benefits when vaccinating healthy children with QLAIV in Belgium. Policies targeting only high-risk individuals or the youngest provide limited herd protection, as school-age children are important influenza vectors in the community.
PMID: 27272706 [PubMed - as supplied by publisher]
[h=1]Estimates of the Public Health Impact of a Pediatric Vaccination Program Using an Intranasal Tetravalent Live-Attenuated Influenza Vaccine in Belgium.[/h] Gerlier L[SUP]1[/SUP], Lamotte M[SUP]2[/SUP], Dos Santos Mendes S[SUP]3[/SUP], Damm O[SUP]4[/SUP], Schwehm M[SUP]5[/SUP], Eichner M[SUP]6,[/SUP][SUP]7[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]OBJECTIVES:[/h] Our objectives were to estimate the public health outcomes of vaccinating Belgian children using an intranasal tetravalent live-attenuated influenza vaccine (QLAIV) combined with current coverage of high-risk/elderly individuals using the trivalent inactivated vaccine.
[h=4]METHODS:[/h] We used a deterministic, age-structured, dynamic model to simulate seasonal influenza transmission in the Belgian population under the current coverage or after extending vaccination with QLAIV to healthy children aged 2-17 years. Differential equations describe demographic changes, exposure to infectious individuals, infection recovery, and immunity dynamics. The basic reproduction number (R [SUB]0[/SUB]) was calibrated to the observed number of influenza doctor visits/year. Vaccine efficacy was 80 % (live-attenuated) and 59-68 % (inactivated). The 10-year incidence of symptomatic influenza was calculated with different coverage scenarios (add-on to current coverage).
[h=4]RESULTS:[/h] Model calibration yielded R [SUB]0[/SUB] = 1.1. QLAIV coverage of 75 % of those aged 2-17 years averted 374,000 symptomatic cases/year (57 % of the current number), 244,000 of which were among adults (indirect effect). Vaccinating 75 % of those aged 2-11 years and 50 % of those aged 12-17 years averted 333,200 cases/year (213,000 adult cases/year). Vaccinating only healthy children aged 2-5 years generated direct protection but limited indirect protection, even with 90 % coverage (40,800 averted adult cases/year; -8.4 %). Targeting all children averted twice as many high-risk cases as targeting high-risk children only (8485 vs. 4965/year with 75 % coverage). Sensitivity analyses showed the robustness of results.
[h=4]CONCLUSIONS:[/h] The model highlights the direct and indirect protection benefits when vaccinating healthy children with QLAIV in Belgium. Policies targeting only high-risk individuals or the youngest provide limited herd protection, as school-age children are important influenza vectors in the community.
PMID: 27272706 [PubMed - as supplied by publisher]