Since the start of the COVID-19 pandemic, many countries have suffered economically, causing billions of dollars in losses worldwide. In response to this, many countries have taken emergency measures to ensure that the impact does not have huge economic implications in terms of rapid recession. In Africa, where many countries have taken measures to deal with the decline in economic activity, mainly through fiscal and monetary policies, including Tunisia. In addition, socio-economic statuses continued to change instantly and stochastically, more after large numbers of people lost their daily jobs with new measures to stop the spread of the COVID-19 virus. This article attempts to model the effect of the COVID-19 pandemic on tourism and freight in Europe, USA and China using an analysis of the Markov chain in discrete time. In addition, the document seeks to find the ultimate effect of Covid-19 on air transport in the main economic sectors. The results of this document should help government and global investors understand the different economic stimulus planning plans to launch in the "hard hit" sectors of the economy to reduce the impact on tourism and freight. The information should help formulate a post-COVID-19 economic recovery plan for the global economy.