How dangerous will be the second coronavirus wave?

As the coronavirus pandemic spreads across the world, doctors are increasingly warning of a second wave of infections with countries easing down the conditions of the lockdown. A century ago, the Spanish flu epidemic's second wave was far deadlier than its first, in part because authorities allowed mass gatherings from Philadelphia to San Francisco.

Experts in hard-hit Italy, which just began easing some restrictions, warned lawmakers in the Senate that a new wave of virus infections and deaths is coming. They urged intensified efforts to identify possible new victims, monitor their symptoms and trace their contacts.

Germany warned of a second and even third wave, and threatened to re-impose virus restrictions if new cases can't be contained. German Chancellor Angela Merkel was meeting Wednesday with the country's 16 governors to discuss further loosening restrictions that have crippled Europe's largest economy.

“There will be a second wave, but the problem is to which extent. Is it a small wave or a big wave? It's too early to say,'' said Olivier Schwartz, head of the virus and immunity unit at France's Pasteur Institute.

Britain has begun recruiting 18,000 people to trace contacts of people infected, and aims to have them ready to work later in May. British officials now acknowledge that they should have done more testing and tracing early in the outbreak, and could learn from South Korea, which brought its outbreak under control by rigorously testing, tracing and isolating infected people.