Modeling the potential public health and economic impact and cost-effectiveness of vaccination strategies using an adapted COVID-19 vaccine in Guatemala

This peer-reviewed article led by reserachers at Pfizer models the potential public health impact, economic impact, and cost-effectiveness of using an adapted COVID-19 vaccine in Guatemala. The study adapts a previously published combined Markov-decision tree model to compare targeted COVID-19 vaccination strategies with no additional vaccination over a one-year time horizon, using Guatemala-specific data where available and regional inputs where local data were not available. 

Key findings

• Vaccinating adults aged 65 years and older and high-risk adults aged 18–64 years was estimated to prevent 12,933 symptomatic cases, 12,811 outpatient cases, 122 hospitalizations, four deaths, and generate 353 QALYs compared with no additional vaccination.
• Under base-case assumptions, this targeted vaccination strategy was cost-saving from both the public payer and societal perspectives, with estimated direct cost savings of US$9.4 million and societal cost savings of US$10.4 million.
• Expanding eligibility to adults aged 60 years and older and high-risk adults aged 18–59 years increased the estimated benefits, preventing 15,999 symptomatic cases, 136 hospitalizations, and generating 439 QALYs.
• Results were sensitive to assumptions about underreporting of infections, highlighting the importance of accurately estimating the true COVID-19 burden.
• The main drivers of uncertainty were vaccine duration of protection, attack rates among older adults, outpatient illness duration, and quality-of-life decrements from symptomatic COVID-19.

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