"CDC"

The new strain, called BA.2.12.1, makes up about a fifth of new COVID-19 cases in the United States, according to data released Tuesday by the CDC.

The CDC cited the spread of the BA.2 Omicron subvariant in its decision to extend the mask requirement. The subvariant now makes up more than 85 percent of new COVID-19 cases in the United States.

The Centers for Disease Control and Prevention (CDC) on Monday urged Americans to avoid travel to Hong Kong, New Zealand and Thailand over COVID-19 cases.

"We need to be prepared, and we need to be ready for whatever comes next," CDC Director Rochelle Walensky said.

"Much of the withheld information could help state and local health officials better target their efforts to bring the virus under control," read a report by The New York Times.

"Physicians are concerned that these recommendations put our patients at risk and could further overwhelm our health care system," said a statement.

The guidance does not require a negative test to leave isolation or quarantine, which experts worry may drive up transmission and new cases. Another concern voiced by epidemiologists is that it fails to distinguish between vaccinated and unvaccinated people.

A total of 88 vessels are under CDCs investigation or observation for COVID-19 outbreaks. Four other vessels are also being monitored by the CDC, according to the latest data.

The change is motivated by science demonstrating that the majority of SARS-CoV-2 transmission occurs early in the course of illness, generally in the one to two days prior to onset of symptoms and the two to three days after, according to the CDC.

"Our goal is to keep healthcare personnel and patients safe, and to address and prevent undue burden on our healthcare facilities," CDC Director Rochelle Walensky said.

The United States has recorded an average of about 120,000 daily new cases this week, an increase of nearly 40 percent compared to a week before, according to the U.S. CDC.

Health officials said Tuesday that even as the world learns anew how "unpredictable" the coronavirus is, with still so much unknown about the omicron variant that has countries around the world sounding alarms, the United States is far better prepared to fight and contain it than it was with other highly transmissible variants, such as delta.