Health and Science

Watch live: World Health Organization holds press conference on the coronavirus outbreak as pandemic worsens

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The World Health Organization is holding a news briefing Friday on the coronavirus pandemic, which has infected more than 13.83 million people worldwide and killed at least 590,600, according to data compiled by Johns Hopkins University. 

On Monday, WHO officials said the United States and Brazil accounted for half of the new daily coronavirus cases as countries across the globe struggle to contain their outbreaks. 

The U.S. and Brazil reported 111,319 new Covid-19 cases on Sunday, roughly half of all the new cases disclosed to health authorities worldwide, according to WHO Director-General Tedros Adhanom Ghebreyesus.

"In several countries across the world, we are now seeing dangerous increases in Covid-19 cases and hospital wards filling up again," he said. "It would appear that many countries are losing gains made as proven measures to reduce risk are not implemented or followed."

During Monday's conference, WHO officials also said that patients who recover from Covid-19 may be able to get the coronavirus again, adding that studies suggest their immunity may wane after a few months. 

While emphasizing that scientists don't have a complete answer yet, Dr. Maria Van Kerkhove, head of the WHO's emerging diseases and zoonosis unit, said patients "do mount some level of an immune response."

"We don't know yet whether it's possible with this particular virus ... We do know with other coronaviruses that is the case, and there is some data out there that may suggest that immunity will wane over time, but that is not fully known at this point," she said.

— CNBC's Berkeley Lovelace Jr. contributed to this report.

Read CNBC's live updates to see the latest news on the COVID-19 outbreak.