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Table 1 Model parameters

From: The impact of childhood varicella vaccination on the incidence of herpes zoster in the general population: modelling the effect of exogenous and endogenous varicella-zoster virus immunity boosting

Parameter Description Value Source
Demographic parameters
 Birth rate Fraction of annual birth cohort out of total French population 0.01295 INSEE, www.insee.fr [54]
Biological parameters
 σ Latent period of varicella (average duration: 14 days) 26.07 Brisson et al. [20]
 α Infectious period of varicella (average duration: 7 days) 52.14 Brisson et al. [20]
 δ Waning natural immunity (average duration: 10 years) 0.1 Expert opinion
 g * λ (a) Exogenous boosting against zoster   Brisson et al. [35]
 < 50 years 75% * λ  
 50–64 years 71%* λ  
 > 65 years 50%* λ  
Vaccine parameters
 mmr1 Coverage of first dose of MMR French current coverage 90%  
 mmr2 Coverage of second dose of MMR French current coverage 80%  
 Dose1 Age at first vaccination (in months) 12 Assumption
 Dose2 Age at second vaccination (in months) 18 Assumption
 Introduction time Number of years before maximum vaccination coverage is reached 3 Assumption
 Tv Varicella vaccine efficacy (% successfully vaccinated and temporarily protected) 65% Prymula et al. [45]; NCT00226499
 P Varicella vaccine failures (%) 5% Prymula et al. [45]; NCT00226499
 1-Tv-P Varicella vaccine-recipients partially protected (%) 30% 100%-Tv-P
 Wv1 Waning rate for 1 dose of varicella vaccine (duration 17 years) 0.0588 Silverman et al. [55]
 Wv2 Waning rate for 2 doses of varicella vaccine (lifelong protection) 1e− 6 Expert opinion
 Ki * λ (a) Rate of exogenous boosting 0.91 * λ (a) Brisson et al. [20]
 h Relative VZV reactivation after varicella vaccination 0.167 Brisson et al. [20]
 b * λ (a) Rate of infection among vaccinated susceptibles 0.73 * λ (a) Brisson et al. [20]
 m Relative infectiousness of infected vaccine-recipients versus non-vaccine-recipients 0.5 Brisson et al. [20]
  1. Note: MMR measles, mumps and rubella, MMVR measles, mumps, rubella, and varicella, INSEE National Institute of Statistics and Economic Studies (Institut national de la statistique et des études économiques), VZV varicella zoster virus, WHO World Health Organization