Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Situational Awareness; Distraction; Confusion
Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Illness / Injury
General Flight Cancelled / Delayed; General Maintenance Action
Human Factors; Procedure; Company Policy
We had to return to the gate and remove a passenger exhibiting the signs and symptoms of COVID-19.  We had just finished de-icing the aircraft and when I called the FA to notify her; she informed me that we had a passenger in the back of the airplane that was visibly ill. She said he was coughing; sneezing; not wearing a mask; and he refused to wear a mask despite repeated attempts by her to give him one. A doctor who was sitting in front of him said he had also gotten up to use the lavatory about five times since they had boarded. She also said the other passengers were starting to panic and become upset with him. I told her to keep them calm and we were going to return to the gate as soon as I spoke to Dispatch so they could put the wheels in motion per airline protocol. During a global pandemic; a visibly sick passenger was able to get through check-in; security; walk through the terminal; past a gate agent; and onto an airplane with [XX] other passengers and [X] crew members.I got Person Y on the phone; told him I wanted to return to the gate; and asked him what I needed to do to adhere to Airline's current COVID-19 protocol. He said he needed to make some phone calls and would get right back to me. While I was waiting I called operations on the radio to tell them what was going on and find out which gate they wanted us to return to once got back to the ramp. Person Y called me back and said once we returned to the gate EMS was going to evaluate the passenger and we would go from there. I notified the FA and then notified the passengers as delicately as I could of the situation. Once we got back to the gate EMS came on board and went back to the passenger who was in seat X. They escorted him off of the airplane and into the ambulance at the bottom of the jet bridge where they evaluated him. While this was going on I called Person Z to inform him of the situation as well. A few minutes later the EMS came up and said he wanted to speak to me out on the jet bridge. He informed me that the passenger was 'positive for every screening marker of COVID-19.' While I was speaking to him the station manager was on the phone with another woman and said she wanted to speak to me. I told her what had just transpired and she said we could deplane to have the entire aircraft fully sanitized or we could continue to ZZZ1 as is and the decision was up to me. I told her we would deplane to have the aircraft cleaned. I got back on the aircraft and made another PA to the passengers explaining what we were going to do. Once they finished cleaning the aircraft I spoke to Person Y again; verified the fuel; weather; etc.; from my release was still valid; boarded the [XX] passengers who still wanted to travel to ZZZ1; and we left. Even though it's already 2+ months into this pandemic I think mandatory masks for all passengers and screening at security checkpoints by TSA or at the very least at the gate should be mandatory. Social distancing isn't an option in a closed environment with recirculating air - like that on an airplane.
Air carrier Captain reported a passenger was removed from flight due to exhibiting COVID-19 symptoms.  Reporter suggested masks should be mandatory for all passengers and there should be screening for COVID-19 symptoms at security checkpoints.