“The president yesterday was tested for the presence of coronavirus. The result turned out to be positive. The president is fine. We are in constant contact with the relevant medical services,” Spychalski said on Twitter.
Spychalski later said that he would also go into quarantine due to the positive test.
Duda’s infection comes as the country faces a surge in the COVID-19 epidemic, with new infections hitting a daily record of more than 13,600 on Friday.
Duda, 48, holds a mainly ceremonial role, but has the power to veto legislation. He is an ally of the ruling nationalist Law and Justice (PiS) party.
From Saturday, more restrictions to curb the spread of the virus are due to come into force in Poland, including a two-week shutdown of restaurants and bars.
The Health Ministry reported 153 coronavirus deaths on Friday, taking the total toll to 4,172.
(Reporting by Marcin Goclowski Editing by Jason Neely and Frances Kerry)