TY - JOUR
T1 - The estimated impact of natural immunity on the effectiveness of human papillomavirus vaccination
AU - Matthijsse, Suzette
AU - Hontelez, Jan
AU - Naber, Steffie
AU - van Rosmalen, Joost
AU - Rozemeijer, Kirsten
AU - Penning, Corine
AU - Bakker, Rachel
AU - Ballegooijen, Marjolein
AU - Driesprong - de Kok, Inge
AU - de Vlas, Sake
PY - 2015
Y1 - 2015
N2 - Background: Mathematical modelling is used to estimate the effectiveness of HPV vaccination. These estimates depend strongly on herd immunity and thus on naturally acquired immunity, a mechanism of which little is known. We estimated the impact of different vaccination strategies on HPV-16 and HPV-18 transmission and cervical cancer incidence in the Netherlands, considering different acquired immunity mechanisms. Methods: We used the STDSIM microsimulation model, and considered two mechanisms for acquired immunity after infection: (I) full immunity with variable duration; (II) cumulatively decreasing susceptibility to reinfection. Girls aged 13-16 years received vaccination (94.7% efficacy for HPV-16 and 92.3% for HPV-18) during a once-off catch-up campaign with 50% coverage, followed by annual vaccination of 12year-old girls (60% coverage). Alternative vaccination scenarios included increased coverage, including boys, and lower vaccine efficacy. Results: HPV-16 incidence reduced by 64% under mechanism I and 75% under mechanism II; HPV-18 incidence reduced by 58% and 73%, respectively, and these reductions lead to 48-56% fewer cervical cancer cases. Increasing coverage can lead to over 96% reduction in HPV incidence. Vaccinating boys reduced incidence by 79-89% for HPV-16 and 83-98% for HPV-18 in women. Conclusions: Effectiveness estimates of HPV vaccination differ slightly between different acquired immunity mechanisms, yet these differences are unlikely to affect policy decisions. Offering vaccination to boys as well may be considered to further reduce cancer incidence. (C) 2015 Elsevier Ltd. All rights reserved.
AB - Background: Mathematical modelling is used to estimate the effectiveness of HPV vaccination. These estimates depend strongly on herd immunity and thus on naturally acquired immunity, a mechanism of which little is known. We estimated the impact of different vaccination strategies on HPV-16 and HPV-18 transmission and cervical cancer incidence in the Netherlands, considering different acquired immunity mechanisms. Methods: We used the STDSIM microsimulation model, and considered two mechanisms for acquired immunity after infection: (I) full immunity with variable duration; (II) cumulatively decreasing susceptibility to reinfection. Girls aged 13-16 years received vaccination (94.7% efficacy for HPV-16 and 92.3% for HPV-18) during a once-off catch-up campaign with 50% coverage, followed by annual vaccination of 12year-old girls (60% coverage). Alternative vaccination scenarios included increased coverage, including boys, and lower vaccine efficacy. Results: HPV-16 incidence reduced by 64% under mechanism I and 75% under mechanism II; HPV-18 incidence reduced by 58% and 73%, respectively, and these reductions lead to 48-56% fewer cervical cancer cases. Increasing coverage can lead to over 96% reduction in HPV incidence. Vaccinating boys reduced incidence by 79-89% for HPV-16 and 83-98% for HPV-18 in women. Conclusions: Effectiveness estimates of HPV vaccination differ slightly between different acquired immunity mechanisms, yet these differences are unlikely to affect policy decisions. Offering vaccination to boys as well may be considered to further reduce cancer incidence. (C) 2015 Elsevier Ltd. All rights reserved.
U2 - 10.1016/j.vaccine.2015.08.079
DO - 10.1016/j.vaccine.2015.08.079
M3 - Article
SN - 0264-410X
VL - 33
SP - 5357
EP - 5364
JO - Vaccine
JF - Vaccine
IS - 41
ER -