Poland reported a total of 17,260 new cases of coronavirus over the past 24 hours - a record for this year - with 398 more virus-related deaths.
Health ministry spokesman Wojciech Andrusiewicz blamed the increase on the spread of the variant first detected in Britain as well as "increased looseness" among Poles in respecting virus restrictions.
He said an additional 1,500 beds for Covid-19 patients would be opened up around Poland in the coming days, including in some temporary hospitals.
Government spokesman Piotr Muller said there had been a slight decrease in the rate of increase, "but there is still a long way to go before we can say that the third wave has calmed down".
Poland locked down at the start of the pandemic last year and was initially spared the worst, but it has been badly affected by a second wave at the end of last year and again this year.
The government last month eased restrictions, including reopening shopping centres, museums, hotels and theatres but it has been forced to reverse those changes in two northern regions in the past couple of weeks because of soaring case rates.
Officials are not ruling out further nationwide tightening.
Brazil reaches new daily virus toll record
Brazil broke its record for new daily Covid-19 deaths with nearly 2,000 fatalities, as the pandemic overwhelms hospitals and vaccinations progress slowly.
The Health Ministry reported a daily total of 1,972 new deaths in the country, which has the world's second-highest overall toll, exceeded only by the United States.
It also reported 70,764 new cases of Covid-19, meaning 11.1 million people have now caught the virus in the country, while a total of 268,370 have died.
The previous daily death record was set on 3 March with just over 1,900 fatalities. The figure has been rising steadily over the past two weeks.
Brazil posts new record of Covid-19 deaths in a day. | Read more: https://t.co/Ger1IsmQVh pic.twitter.com/P178w8UnCZ
— RTÉ News (@rtenews) March 10, 2021
Brazil is facing a dire situation with intensive care units more than 80% occupied in 25 of Brazil's 27 capital cities, according to a report released yesterday by public health institute Fiocruz.
"The fight against Covid-19 was lost in 2020 and there is not the slightest chance of reversing this tragic circumstance in the first half of 2021," epidemiologist Jesem Orellana of Fiocruz/Amazonia said.
"The best we can do is hope for the miracle of mass vaccination or a radical change in the management of the pandemic," he said.
"Today, Brazil is a threat to humanity and an open-air laboratory where impunity in management seems to be the rule."
President Jair Bolsonaro, who flouts expert advice on fighting the coronavirus, last week urged Brazilians to "stop whining" about Covid-19 and renewed his attacks on stay-at-home measures.

World Health Organization Direct General Tedros Adhanom Ghebreyesus has urged the country to take aggressive steps, warning that Brazil could affect its neighbours and beyond if it did not take the virus seriously.
Brazil's vaccine campaign is progressing slowly. A total of 8.6 million people (4.1% of the population) have received a first dose of vaccine, and only 2.9 million have received a second dose.
The vaccines under use in Brazil are CoronaVac, which was developed by Chinese firm Sinovac, and the AstraZaneca/Oxford vaccine.
Brazil's Ministry of Health says it is in negotiations with other laboratories and recognises that "the national vaccination campaign may be interrupted for lack of doses", according to a letter to the Chinese ambassador published yesterday on the news site G1.
Australia sees no concern with pace of Covid-19 vaccination drive
Australia's pace of Covid-19 immunisation drive is not a cause for concern and the vaccination programme will be completed by the end of October, authorities said, as the country finished administering more than 100,000 first doses.
Australia last month began inoculating its 25 million population but the immunisation drive is running behind schedule as officials slowed vaccinations after two elderly people were inadvertently given four times the recommended dose.
"This is not a race, we have no burning platform in Australia. We are taking it as quickly and carefully and safely as we can," Health Secretary Brendan Murphy told reporters.
"We're not like the US or the UK or most other countries in the world where they've got people in hospital dying. We can take our time, set up our systems, do it safely and carefully, we are expanding our roll-out every day."

Mr Murphy said the country will finish the vaccination programme on time by the end of October, despite the initial delays as the weekly dosage target is expected to reach 1 million by March-end when CSL Ltd begins to locally produce AstraZeneca doses.
Australia has secured about 54 million doses of the AstraZeneca vaccine, which Mr Murphy called the "the workforce vaccine for Australia", with 50 million to be locally produced.
Australia started its vaccination drive much later than many countries as border closures, snap lockdowns and speedy tracing systems kept cases relatively low compared with many other developed countries.
Australia reported no new local cases for the 12th straight day today. It has reported just over 29,000 Covid-19 cases and 909 deaths since the pandemic began.
Greece aims to reopen for UK tourists in May
Greece is aiming to reopen its borders by mid-May in a boost for UK holidaymakers.
Tourism minister Haris Theoharis said the country hopes to welcome foreign tourists from 14 May, depending on the status of the coronavirus pandemic.
During a virtual appearance at travel trade show ITB Berlin, Mr Theoharis commented: "We are approaching the exit from this dark tunnel thanks to the power of the human spirit and the progress of science.
"Please allow me to emphasise that no image could better portray the return to the normality of tourism than the Greek smile, the Greek landscape, the Greek hospitality.
"Regarding 2021, in Greece we are more than optimistic.
"We are ready, we are ready to share the experience of liberation from the unpleasant memories of the pandemic with each and every one of our guests."
Visitors will be required to have been vaccinated, had a recent negative Covid-19 test or have coronavirus antibodies, he explained.
A "pilot" reopening of borders is likely to take place early next month, he added.
People living in England could be permitted to take foreign holidays from 17 May under Prime Minister Boris Johnson's road map for easing coronavirus restrictions.
German and Swiss music festivals cancelled over virus
Seven of the most renowned German and Swiss summer music festivals have been cancelled for the second year in a row due to the coronavirus pandemic, German concert promoters Eventim said.
They include the iconic Rock am Ring at Nuerburgring, one of Europe's largest, the Hurricane festival in Scheessel and the Greenfield festival in Switzerland.

Eventim said festival organisers had decided to cancel due to "ongoing uncertainty about infection rates and mutations".
"2021 was supposed to a summer of reunions, and festival organisers have put a lot of time and work into hygiene concepts to make this possible," said Frithjof Pils, CEO of Eventim Live.
However, the "epidemiological situation" and coronavirus restrictions meant "festivals of this magnitude are not yet feasible at present".
Eventim added that festival ticket-holders for 2021 would be given "a convenient opportunity" to rebook for the following year.
Festivals like Rock am Ring and Hurricane are enormous events held at major motorsport venues which welcome tens of thousands of visitors every year.
Other major European festivals such as Glastonbury in England have also been cancelled in recent months.
Concert halls and music venues have been closed for months in Germany due to the pandemic, and currently have little prospect of reopening in the next weeks.
Case numbers have been rising in recent days despite months of restrictions, with the seven-day incidence rate at 65.4 per 100,000 people on Wednesday, according to official figures.
Additional reporting PA