A recent article (see link below) reviewed influenza models and found "that many influenza pandemics models relied on parameters from previous modelling studies, models are rarely validated using observed data and are seldom applied to low income countries." What are the challenges in validating influenza pandemic models?
Trends in parameterization, economics and host behaviour in influenza pandemic modelling: a review and reporting protocol
Carrasco LR, Jit M, Chen MI, Lee VJ, Milne GJ, Cook AR
Emerging Themes in Epidemiology 2013, 10:3 (7 May 2013)
Abstract http://www.ete-online.com/content/10/1/3/abstract
Provisional PDF http://www.ete-online.com/content/pdf/1742-7622-10-3.pdf