Maurice didn’t debunk the story — but cast some doubt on it.

Norovirus is highly contagious, often spread by food or on surfaces, particularly in crowded conditions. It is a short-lived illness for many people, but it can be dangerous for people with underlying health conditions, young children and those aged 65 and older.There are many different types of norovirus, but typically one dominant strain causes illness outbreaks, Jaykus said.

This year, a new epidemic strain has emerged, called GII.17. This version has circulated at low levels for years, but it was behind a surge in U.S. norovirus outbreaks this past winter.Between Aug. 1 and April 9, more than 2,400 suspected or confirmed norovirus outbreaks were reported to a CDC monitoring system, roughly double for the same period a year earlier. The GII.17 strain has been responsible“It’s new to the population,” Jaykus said, which means most people don’t have immunity to the germ, so it can spread more widely.

People infected with norovirus typically shed “literally billions of viral particles,” said Schaffner, the food safety expert. And it only takes a few viral particles to make someone sick.The first rule should be for sick people to stay home, he said. That’s not possible on a cruise.

If people get sick on a cruise ship, they’re required to report the illness and isolate themselves, but many fail to do so.

“You spent all this money for a fancy cruise and you’re feeling a little bit under the weather, so you tough it out,” Schaffner said. “But in the meantime, now you spread the virus.”The wetlands in the world’s hottest region were thought beyond resurrection.

Weisman writes that to Alwash, however, “impossible often masks a lack of imagination.” He marshaled the resources to restore much of the wetlands and a miracle followed: wildlife returned..Some of Weisman’s chapters will make readers wish they had paid more attention in high school science and chemistry classes.

Scientists at the Massachusetts Institute of Technology have made astonishing progress in developing commercial-scale fusion energy that could produce great quantities of clean energy. Such breakthroughs are critical on a planet now dependent on fossil fuels, which produce carbon dioxide that traps heat in the atmosphere.To those who scoff at mentions of human-caused environmental catastrophe as a hoax or fake news, consider this: Weisman’s bibliography runs 74 pages. And the type is small. He spent several years researching and reporting on this book and visited a dozen countries.