OBJECTIVES: Some countries recommend pertussis (whooping cough) vaccination boosters for at-risk adults. In Colombia, this is recommended for HIV patients but not other at-risk groups.

This study estimates the budgetary impact of introducing Tdap (tetanus-diphtheria-acellular pertussis) vaccine to prevent pertussis over 5 years in at-risk adult populations from the payer’s perspective in Colombia.

METHODS: The total budget impact of Tdap booster vaccine entry into national immunization for at-risk populations (asthma, COPD and HIV; 1 dose at 20 years old), number of pertussis cases, outpatients with complications and hospitalization cases avoided, were assessed 5 years after entry (2025–2029) in Colombia. Scenarios with and without Tdap booster were compared, assuming 10% coverage with 74% market share. Demographic data were sourced from the Colombian Department of Economic and Social Affairs Population Division, epidemiology data from published literature and costs of healthcare resource use from the Colombian Ministry of Health. Costs are expressed in 2023 USD$.

RESULTS: Assuming just 10% vaccination coverage, introducing Tdap for asthma, COPD and HIV patients could avert 135, 103 and 50 pertussis cases, 13, 10 and 5 outpatients with complications, and 8, 9 and 3 hospitalization cases, respectively.

Tdap immunization costs were 1.45M USD$ for asthma, 1.48M USD$ for COPD and 290,751 USD$ for HIV patients. Total budget impact in direct medical cost to vaccinate 10% of at-risk populations were 1.30M USD$, 1.24M USD$ and 137,464 USD$, respectively.

Reduction in medical costs were 141,853 USD$ for asthma, 164,557 USD$ for COPD and 46,268 USD$ for HIV. Reduction in exacerbation costs were 7,653 USD$ for asthma, 80,845 USD$ for COPD and 107,018 USD$ for HIV.

CONCLUSIONS: Tdap vaccination for at-risk populations in Colombia could substantially decrease pertussis disease burden and associated health care utilization. A proportion of the national immunization budget will be required to protect those at highest risk.