White House senior adviser Stephen Miller has tested positive for coronavirus, adding to the growing list of Donald Trump officials who've contracted the disease within the past week.

Miller confirmed his diagnosis in a statement Tuesday to NPR: "Over the last 5 days I have been working remotely and self-isolating, testing negative every day through yesterday. Today, I tested positive for COVID-19 and am in quarantine."

The news comes just days after President Trump confirmed he and first lady Melania had tested positive for the potentially fatal virus. The president returned to the White House on Tuesday, after spending three days at Walter Reed Medical Center, where he received treatment for the disease.

"I learned so much about coronavirus. One thing that’s for certain, don’t let it dominate you," Trump said in a video Monday night. "Don’t be afraid of it. You’re going to beat it. We have the best medical equipment. We have the best medicines, all developed recently, and you’re going to beat it. Don’t let it dominate. Don’t let it take over your lives. Don’t let that happen."

Miller has become one of Trump's top aides and speechwriters, and was reportedly part of the team that helped the president prepare for last week's debate against Joe Biden. Others who were involved in that preparation included Trump's senior counselor Hope Hicks, White House counselor Kellyanne Conway, Trump's campaign manager Bill Stepien, and former New Jersey Gov. Chris Christie—all of whom have tested positive for COVID-19 over the past week.

According to Politico, at least 34 people within Trump's orbit have contracted the virus in recent days. Miller's wife, Katie Miller, tested positive for COVID-19 back in May. She is the spokesperson for Vice President Mike Pence and is expecting a child with her husband.