Portugal is largely shut down, pursuant to the state of emergency enacted during the week. One can venture out of the home to purchase pharmaceuticals and foodstuffs, as well as for a walk and to pursue individual sporting activities (e.g., jogging); and, quite obviously, those who cannot work from home are free to go to work, for instance, persons employed in the agricultural sector. The borders of Portugal are not entirely closed at the moment, though during the past week the EU Member States agreed to close the external borders of the Schengen Zone, within which Portugal is situated, for a thirty-day period to non-nationals of EU Members States, save long-term residents, family of Member State citizens, healthcare workers, diplomats and the like. Having studied closely the relevant decree of the Government of Portugal, I am pleased to report that wine (including port) tastings are not prohibited expressly, though the ban on public gatherings would presumably require visitors to quintas to serve themselves.
For those with nothing better to do, the latest decree is to be found here in English translation:
https://www.safecommunitiesportugal.com ... 2019-ncov/
The pressing question is how long these restrictions, or variants thereof, shall remain in place. The answer to this query will rest upon how long the virologists are able to trump the economists in the formulation of Portuguese policy. As tourism accounts for fifteen percent of Portuguese GDP, within an economy which has never recovered properly from the financial crisis of a decade ago, my admittedly imperfectly-informed calculus is that the current arrangements could be left in place for up to eight weeks before very serious economic consequences, many of them of an irreversible nature, would start to make themselves felt. As a minimum, property developers and speculators active in Lisbon and Porto are going to take a (well-deserved) kicking.
Readers of the FTLOP forum will know better than myself how deleterious the absence (or a significant decline in the numbers) of tourists in the Douro for a season would prove to be for the region and elements of the port trade. There can be no doubt that grapes shall continue to be grown, harvested, turned into wine and exported, as in any other year. My guess is that growers (and other entrepreneurs) who have invested heavily in tourist infrastructure, such as hotels and restaurants, are going to get hammered if they are not capitalized sufficiently to withstand a season with few visitors. At this juncture, I am assuming that even where the restrictions on movement are lifted, foreigners - whom I believe to make up the bulk of tourists to the Douro - are likely to remain close to home during the coming summer insofar as CORVID-19 shall remain a persistent threat for the balance of this year, leading most potential visitors to conclude that they ought best not to engage in activities which might see them quarantined in Portugal or otherwise hospitalized in a provincial medical facility.