BANGKOK — Saudi Arabia cut travel to Islam’s holiest sites, South Korea toughened penalties for those breaking quarantines and airports across Latin America looked for signs of sick passengers as a new virus troubled places around the globe.

With the number of sick and dead rising, the crisis gave way to political and diplomatic rows, concern that bordered on panic in some quarters, and a sense that no part of the world was immune.

“Viruses don’t know borders and they don’t stop at them,” said Roberto Speranza, the health minister in Italy, where northern towns were on army-guarded lockdowns and supermarket shelves were bare.

As outbreaks grew sharply in Europe and the Middle East, air routes were halted and border control toughened. But for an illness transmitted so easily, with its tentacles reaching into so many parts of the world, leaders seemed willing to try anything to keep their people — and economies — safe.

Japanese Prime Minister Shinzo Abe called for schools across the country to close for weeks, a decision that impacted 12.8 million students.

“The most important thing is to prevent infections,” said Norinobu Sawada, vice principal of Koizumi primary school, “so there aren’t many other options.”

In South Korea, the hardest-hit country outside China, four Busan markets known for colorful silks and a dizzying array of other wares were shuttered while the country’s military sent hundreds of its doctors and soldiers to aid in treatment and quarantines.

The global count of those sickened by the virus exceeds 82,000, with China still by far the hardest-hit country. Recent days have seen sharp spikes in South Korea, Italy and Iran.

South Korea reported 256 additional cases Friday, raising its total to 2,022, with most occurring in the region around the city of Daegu. Many cases there have connections to a church and health workers are testing thousands of its members.