Ellis has been traveling with President Donald Trump’s personal attorney Rudy Giuliani as the campaign challenges election results, unsuccessfully, in various states.
Giuliani is currently in the hospital being treated for COVID-19.
Ellis attended a White House Christmas party on Friday with senior staff, according to Axios. Her COVID-19 diagnosis has some worried whether she was contagious at the time of the party.
Ellis came as a guest of Trump’s trade adviser Peter Navarro, and was not seen wearing a mask at the indoor event, according to sources who spoke to Axios.
Ellis appeared to question the existence of the pandemic this summer, sending a tweet on August 30 that claimed "There is no pandemic."
On Monday, after the Arizona legislature shut down because of concerns lawmakers had close contact with Giuliani while he was contagious with COVID-19, Ellis tweeted it was "absolutely unnecessary" to use "COVID as an excuse."