Citing an increase in virus transmission from people traveling, the CDC on Monday issued new guidance that "strongly recommends" that everyone wear a mask on airplanes, buses, trains, taxis and other modes of public transportation.

"Transmission of the virus through travelers has led to -- and continues to lead to -- interstate and international spread of the virus which causes COVID-19," the CDC warned.

The goal of the recommendation is to "mitigate further introduction and spread of COVID-19, and help safely reopen America's economy," the CDC said.

The guidance includes exemptions for children under the age of 2 and those who have a note from their doctor explaining a medical condition.

ABC News' Anne Flaherty contributed to this report.

Weekly new COVID-19 cases and deaths are both on the rise in the U.S., according to an internal Health and Human Services memo obtained by ABC News.

A total of 386,624 new cases were confirmed during the period of Oct. 11-17, representing a 15.4% increase over the previous seven-day period, the memo said.

There were 4,897 deaths recorded Oct. 11-17, an increase of 2.2% over the previous week.

In addition, 21% of hospitals across the country reported having more than 80% of their ICU beds filled. That number is even higher than the 17-18% reported during the summertime peak.

However the national test-positivity rate decreased to 5.3% from 5.7% in week-to-week comparisons, said the memo.

The Trump administration has thrown out 45 ventilators that Russia sent the U.S. last spring, the Federal Emergency Management Agency confirmed in a statement Monday.

The ventilators were delivered as part of a medical aid flight sent last spring by Russian President Vladimir Putin to President Donald Trump.

"He offered a lot of medical, high quality stuff that I accepted and that may save a lot of lives. I'll take it every day," Trump said at the time of the flight, dismissing questions about whether it was Russian propaganda.

ABC was first to report last spring that the U.S. was billed some $660K for the Russian aid supplies, which included thousands of pieces of equipment not typically used in hospitals, like chemical warfare-style gas masks and household cleaning gloves.

When asked whether the U.S. would get its money back, a FEMA spokeswoman suggested that money never changed hands because the supplies are now regarded as a "donation."

"Therefore, no payment was required by the U.S. for the donated goods," she said.

New York and New Jersey had received the ventilators but quickly returned them to the federal stockpile without ever having used them, following reports that five coronavirus patients in St. Petersburg were killed in fires linked to overloaded ventilators.

"The donated ventilators in question were disposed of following strict hazardous waste disposal regulatory guidelines," the FEMA spokeswoman said.

ABC News' Anne Flaherty contributed to this report.

White House Chief of Staff Mark Meadows signaled to reporters that it is premature at this point to answer specific questions from state governors about vaccine distribution since there is no vaccine in the final stages.

Over the weekend, the National Governors Association sent a letter to President Donald Trump with several questions about a future vaccine rollout, including questions about funding, supply chain and communication.

"At the appropriate time we’ll be working with them," Meadows said of the governors. "But until we have a vaccine that’s actually in final stages of approval, that distribution and discussions of that would be premature."