Methods
We obtained all hemagglutinin (HA) and neuraminidase (NA) nucleotide sequences of influenza H1N1 available up to December 25, 2020, from Iran and its neighboring countries (i.e., Pakistan, Afghanistan, Turkmenistan, Armenia, Azerbaijan, Turkey, and Iraq). We also performed a Bayesian Markov chain Monte Carlo method to infer the evolutionary dynamic and the most recent common ancestor for the HA and NA sequences.