OBJECTIVES: Chickenpox, a viral disease with particularly high incidence in children under 10 years of age, generates direct costs to the health system and indirect costs due to the expenses that the family must assume in terms of out-of-pocket resources and caregiver time. Chickenpox vaccine was introduced in Colombia in July 2015 for children at one year of age, as part of the national vaccination program. The objective of this study was to establish both the clinical impact of vaccination and estimate the direct and indirect costs of chickenpox for the periods before and after the vaccination program began.

METHODS: Data from four different administrative and epidemiologic surveillance databases were used to estimate incidence rates; one of these databases included partial results of direct medical costs, which were extrapolated. Indirect costs were estimated using base case methodology, with expert panel validation and average wages for maternal (or caregiver) productivity costs. Costs were estimated in Colombian pesos (average exchange rate for the period COP 2523 = 1 USD).

RESULTS: Non-complicated cases of chickenpox were 59,909 in 2014 and 34,716 in 2017, the lowest since records have been kept (equivalent to a 42% reduction). Complicated cases went from 2,257 in 2014 to 1,196 in 2017 (47% reduction). In Bogota, which has the highest vaccination coverage and best quality data, cases were 20,921 (2014) and 7,086 (2017). National indirect costs were ten to twenty times direct costs (USD $9.9 million vs $554 - 951 thousand average per year). The reduction in the total number of cases was 50% in the 1 to 4 years of age, and 43% in those age 5 to 9.

CONCLUSIONS: The impact of chickenpox vaccination is particularly relevant if the societal perspective, with productivity costs, is considered. Future studies could incorporate costs of vaccination in order to estimate cost-effectiveness.