Governments, hospital chains, clinics and entrepreneurs are looking everywhere for the protective gear during a huge shortage — paying five times the price for N95 masks — and a new kind of trader has sprung up to make it all happen.

New urgency: As many as 25 percent of people infected with the new coronavirus may not show symptoms, the director of the U.S. Centers for Disease Control and Prevention said. Some people never get symptoms, others get symptoms later — factors that profoundly complicate efforts to mitigate the virus’s spread.

China: The country has ramped up mask production to nearly 12 times its earlier level of 10 million a day. But many suppliers are unreliable, and navigating customs laws and transport during global shutdowns is confusing.

D.I.Y.: A mask sewed from a pattern or an improvised face covering made from a T-shirt offers some protection.

Here are the latest updates and maps of the pandemic.

In other developments:

United Nations-sponsored climate talks, widely seen as the most important climate meeting of the past four years, were postponed until next year because of the coronavirus pandemic.

Wimbledon, the oldest Grand Slam tennis tournament and a cultural institution in Britain, will not be held in 2020 as the country remains on lockdown.

As infections and deaths mount in Brazil, President Jair Bolsonaro remains adamant that the coronavirus is nothing but a “measly cold.” He is the sole major world leader to question the merit of lockdown measures to fight the pandemic.

The star known as Jaejoong of the K-pop group JYJ pretended to have the virus in a misfired attempt at an April Fool’s Day joke.

Hydroxychloroquine, a malaria drug, helped to speed the recovery of moderately ill coronavirus patients in a small study.

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