Washington (CNN) Vice President Mike Pence said the federal government is ready to combat coronavirus, stating that thousands of additional testing kits are in the mail to state and local clinics.

"We're ready. And this is an all hands on deck effort," Pence said confidently in an interview released Sunday with CNN's Jake Tapper on "State of the Union."

The vice president added, "This weekend, more than 15,000 testing kits have been released. Also the FDA has approved a testing regiment that state and local officials can be using. We're addressing it, we're leaning into it."

His comments come following the first reported US death from coronavirus and amid fears over an outbreak across the nation. The Trump administration has received criticism for downplaying the significance of the virus.

"We have about, about 43 million masks stockpiled today. I want to say to your viewers though, it is not necessary for Americans to go out and buy masks," Pence said.

"We want to make sure -- and the President's made this clear to me, we want to make sure that people that are treating people that have contracted the coronavirus have the protective gear, the masks and the gloves and we're working very energetically to accomplish that," he said.

US Surgeon General Dr. Jerome Adams posted to Twitter Saturday that Americans should stop buying masks. He was responding to face mask shortages as people stocked up due to coronavirus concerns.

"They are NOT effective in preventing general public from catching #Coronavirus, but if healthcare providers can't get them to care for sick patients, it puts them and our communities at risk!" he continued.

Washing your hands, staying home when sick and other "everyday preventive actions" are the best protections, Adams said. He urged people to get a flu shot, as fewer flu patients means more resources to fight the coronavirus.

An official at US Health and Human Services said the agency has launched an investigation into a manufacturing defect in novel coronavirus tests created by the CDC. The coronavirus tests were sent to labs around the US, but weren't able to used for weeks because of a flaw.

The agency is bringing together a team of non-CDC scientists "to better understand the nature and source of the manufacturing defect in the first batch of COVID-19 test kits that were distributed to state health departments and others."

US Food and Drug Administration Commissioner Dr. Stephen Hahn said in a statement: "Upon learning about the test issue from CDC, FDA worked with CDC to determine that problems with certain test components were due to a manufacturing issue. We worked hand in hand with CDC to resolve the issues with manufacturing. FDA has confidence in the design and current manufacturing of the test that already have and are continuing to be distributed. These tests have passed extensive quality control procedures and will provide the high-level of diagnostic accuracy we need during this coronavirus outbreak."

CNN has reached out to CDC for comment.

Coronavirus screening procedures

President Donald Trump announced Sunday new screening procedures for coronavirus. The President tweeted that people will be screened for coronavirus upon arriving in the US if they are traveling from high-risk countries.

The Trump administration announced on Saturday new travel restrictions following news of the first US fatality from the disease. The patient died in Washington and appears to have become ill through community spread, according to Dr. Robert Redfield, director of the US Centers for Disease Control and Prevention, who spoke alongside the President at a briefing Saturday.

Pence offered condolences in the CNN interview, saying that "our hearts go out to that man's family and his friends in that community."

Pence also told Tapper that "it is possible" there could be more deaths from the virus and "more sad news," but "the risk for the average American remains low."

The vice president also said Sunday that clinical trials for a coronavirus vaccine could start in six weeks.