My wife & I were on N001 this year as well. We were both fit & healthy when we embarked but noticed there were a large number of passengers with very bad coughs almost from day 1.
Within 2 weeks I developed a very bad cough which unfortunately I passed onto my wife. She was very poorly & cabin bound as she was so unwell do missed most of the cruise. Eventually she made a visit to the medical centre which was over run with passengers displaying the same symptoms - a hacking cough, nasty chest infection, feeling very weak, etc. After a weeks course of antibiotics & cough medicine my wife was no better. She had lost all sense of taste & smell & also ended up with a severe stomach upset.
She had been down to the Medical Centre, and she was tested for influenza, which was negative. One of the nurses stated that they had never seen anything like it, and they were rapidly running out of medicine.
The Sunday before we docked in The Azores she was taken down to the medical bay & put on intravenous antibiotics, rehydration meds, paracetamol etc. After blood tests & x-rays the Doctor confirmed she had pneumonia & was taken by ambulance from the ship in The Azores along with 5 other passengers.
2 of the 5 were later able to return to the Ventura but unfortunately 3 passengers including my wife were detained in hospital. Fortunately my wife was only kept in for the day but by the time we left the hospital at 9 pm the ship had sailed. We spent a week on the island whilst awaiting repatriation organised by our insurance company.
My wife is fully recovered now but it took her a number of weeks to finally recover.
It may not have been Covid 19, but may have been a previous version.
I also find it strange that one of the people on here who states they had seen nothing untowards had a long conversation with me about the sickness on board.