Does US full vaccination against COVID-19 immunize correspondingly S&P500 index: Evidence from the NARDL approach

This study analyzes the impact of COVID-19 full vaccination shocks on the US stock market in the period January 14, 2021– August 20, 2021. Using the Nonlinear Autoregressive Distributed Lag model, we find that the positive and negative COVID-19 full vaccination growth shocks have a positive and symmetrical impact on the US stock market over the long run. Additionally, the short-run findings provide that the US stock market reacts negatively with delay to the positive and negative COVID-19 full vaccination growth shocks. The study findings provide good insights that COVID-19 full vaccination immunizes accordingly to the S&P 500 index in the long run. The study results indicate that the impact of positive and negative COVID-19 full vaccination growth shocks on the stock market in the short run differs from that in the long run. This research bears important implications: governments should implement preventive measures with vaccination to recover the stock market. Policy makers ought to urge adopting policy measures to reduce panic and boost investor confidence during economic and health crises.