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Objective: To explore the inputs and outputs of areas with different anti-HAV prevalence rates on universal childhood vaccination, and to provide a scientific basis for the formulation of the immunization strategy., Methods: Since hepatitis A vaccination was scheduled at 12 and 18 months of age for all the healthy children, a single cohort including 1 000 000 individuals was formed in 2009, using the Chinese inactivated vaccine. Decision analysis was used to build Markov-decision tree model. The universal childhood hepatitis A vaccination was compared with non-vaccination group to evaluate the number of symptomatic infection, hospitalization, death, quality-adjusted life years (QALYs) lost, and the incremental cost-utility from the health system and the societal perspectives. Outcomes of the vaccination for the next 70 years were also predicted. The process of analysis was run separately in five regions defined by the anti-HAV prevalence rates (around 50%, 50% - 69%, 70% - 79%, 80% - 89% and > 90%). Sensitivity analysis was performed to test the stability or reliability of the results, and to identify sensitive variables., Results: The study projected that, in the lowest, lower, and intermediate infection regions, the cost and output indicators of universal childhood hepatitis A vaccination were all lower than non-vaccinated group. Universal vaccination could gain QALYs and save both costs from the health system or the society. In the regions with higher infection rate, the output indicators of universal childhood hepatitis A vaccination were lower than in those non-vaccinated groups, except for the number of death due to hepatitis A, which had a 20 cases of increase. The model also predicted that in the highest infected region, universal vaccination would increase 4 560 814 and 5 840 430 RMB Yuan in the total costs from both the health system and the societies, respectively, when compared to the non-vaccination groups. Universal vaccination would also decrease the numbers of symptomatic infection, hospitalization, and QALYs lost, but would increase 51 deaths due to hepatitis A, and 1507, 1929 more RMB Yuan for each QALY gained from the health system and societal respectively, in the regions with highest infection rate. Sensitivity analyses discovered that the infection rate among those susceptible population and the proportion of those who initially under protection but subsequently lost their immunity every year, were the two main sensitive variables in the model., Conclusion: Our research discovered that the universal vaccination strategy should be based on the protective period of the vaccine and the anti-HAV prevalence in different endemic areas.

The changes of annual incidence rates were predicted for 7 cohorts of different ages either with or without vaccination. Cost-effectiveness ratio (CER) was estimated by the annual differences of HA incidence of the two scenarios at 15 years after inoculation, the medical costs and quality of life impact (QALY) for conditions related to the vaccination and disease. The estimated age specific HA incidence rates of the cohorts without vaccination fitted the observed age specific HA incidence rates quite well, indicating the correctness of our calculation models. Under the basecase assumptions, vaccination in general population would entail medical costs. The average CER was 153,277.6 Yuan/QALY, 11 times more than the average per-capita GNP in 1994. The basecase CERs varied from 113,369.3 Yuan/QALY in 10-19 years of age to 292,138.3 Yuan/QALY in age group 50-years. However, much better CERs are found when vaccination is directed toward a high risk population. In this case, widespread use of HAV vaccine in general population with intermediate epidemicity would not be cost-effective while it should be only focused on the high risk population. Sensitivity analysis showed that none of the basic variables might change this conclusion.