He was speaking after the government on Thursday announced a new set of restrictions from December 28 to January 17 as the authorities battle an epidemic that has claimed over 24,000 lives in Poland.
Shopping malls will have to close for three weeks, though grocery stores and drugstores will be exempt. A curfew will be imposed on New Year's Eve, with restrictions on free movement from 7pm on December 31 to 6am on January 1.
Health Ministry spokesman Wojciech Andrusiewicz told reporters on Friday: “If we started the march towards a third wave, for example by irresponsible behaviour on New Year's Eve or during the [school] winter holidays, it would be realistic to exceed the threshold of 30,000 infections daily and even reach 40-45,000 infections a day.”
He added that irresponsible behaviour could lead to the number of deaths increasing to 1,000 or more a day.
Poland on Friday reported 11,013 new coronavirus infections and 426 more deaths, bringing its total number of cases to 1,182,864 and fatalities to 24,771.
Health Minister Adam Niedzielski has warned that "the spectre of a third wave” which started from Poland’s current level of some 10,000 new infections a day would push the country’s public health services beyond their capability to cope.
On November 25, the country reported its highest daily toll of 674 deaths related to the coronavirus.
On November 7, the Polish health ministry confirmed 27,875 new single-day cases, the most since the pandemic hit the country in early March.