New York Gov. Andrew Cuomo announced Tuesday that five states -- Alaska, Arizona, Delaware, Maryland and Montana -- have been removed from the Empire State's coronavirus travel advisory list, while the U.S. territory of Guam has been added.

The advisory mandates a 14-day self-quarantine for travelers arriving from areas "with significant community spread." That list now includes Alabama, Arkansas, California, Florida, Georgia, Guam, Hawaii, Iowa, Idaho, Illinois, Indiana, Kansas, Kentucky, Louisiana, Minnesota, Missouri, Mississippi, North Carolina, North Dakota, Nebraska, Nevada, Oklahoma, Puerto Rico, South Carolina, South Dakota, Tennessee, Texas, Utah, Virginia, Virgin Islands and Wisconsin.

New York state has had a rate of positive COVID-19 tests below 1% for 18 straight days, according to Cuomo, who warned "this pandemic is not over" and urged residents to "stay vigilant and be careful."

"New Yorkers made enormous sacrifices to get our numbers as low as they are today, and we don't want to give up an inch of that hard-earned progress," Cuomo said at Tuesday's press briefing. "That's why these travel advisory precautions are so important -- we don't want people who travel to states with high community spread to bring the virus back here."

Face masks will be obligatory for children aged 6 and older while at schools in Spain's central capital.

Madrid's regional premier, Isabel Diaz Ayuso, announced the new measure at a press conference Tuesday, while presenting a strategy for the safe return to schools amid the coronavirus pandemic. She said class sizes will also be reduced and thousands more teachers will be hired on a temporary basis.

Diaz Ayuso noted that, if Madrid's epidemiological situation improves, face masks will only be mandatory for students aged 11 and up. The region is planning for the staggered reopening of schools in September.

With over 405,000 diagnosed cases of COVID-19 so far, Spain has the highest case count of any country in Europe. The day-to-day increase of new cases has been steadily climbing since Spain emerged from a more than three-month national lockdown in late June.

Last week, Spain's head of health emergencies, Dr. Fernando Simon, warned that "things are not going well" regarding a recent spike of infections.

"Each day, we are seeing more and more transmission," Simon said.

South Korea has ordered the closure of schools in the capital amid a rise in coronavirus infections there.

South Korean Education Minister Yoo Eun-hae said Tuesday that nearly 200 students and teachers have been infected in the Seoul metropolitan region over the past two weeks. Most students at kindergartens, elementary, middle and high schools will return to online learning at least until Sept. 11. Those in their final year of high school will continue to take in-person classes so their studies are not disrupted ahead of the national college exams, Yoo said.

South Korea's Centers for Disease Control and Prevention recorded 280 new cases of COVID-19 and one death on Monday, bringing the country's total to 17,945 cases and 310 deaths.

South Korea once had the largest COVID-19 outbreak outside China, where the virus first emerged, but health authorities were able to bring it under control with an extensive "trace, test and treat" strategy. Now, infections are on the rise in Seoul, home to over 25 million people, as well as in other parts of the country.

Germany has issued a travel warning for parts of France, including Paris and Marseille, due to high levels of coronavirus infection there.

The German government announced Monday that travelers returning from Ile-de-France and Provence-Alpes-Cote-d’Azur regions will be required to be tested for COVID-19 upon arrival and then must self-quarantine while awaiting the test results.

France’s national public health agency recorded 1,955 new cases of COVID-19 and 15 coronavirus-related fatalities on Monday, bringing the total to 244,854 confirmed cases and 30,528 deaths. The country is among the hardest-hit in Europe.

ABC News’ Ibtissem Guenfoud contributed to this report.