Police are investigating an alleged coronavirus 'superspreader' over reports he travelled to and from Spain even though he was suffering symptoms of the disease.
The man, believed to be from Heywood, fell seriously ill after he flew back to Manchester Airport.
He is now believed to be in intensive care.
Despite his condition, Greater Manchester Police has launched an investigation into alleged breaches of restrictions designed to prevent the spread of coronavirus.
People who have developed Covid-19 symptoms such as a new continuous cough, a high temperature or a loss of taste or smell are advised to self-isolate for ten days following onset and arrange a test.
People who fail to self-isolate despite a positive test face a fine of up to £10,000. They can also be prosecuted. Official advice says people should not travel if they have experienced symptoms within seven days of departure and must quarantine for ten days on their return from Spain.
It is feared a small number of irresponsible 'superspreaders' could be behind much of the second wave of the disease being experienced in Greater Manchester and elsewhere.
Last month Greater Manchester Mayor Andy Burnham revealed one person, who had gone out drinking after returning from holiday, could be partly responsible for a spike of cases in Bolton.
GMP is now dishing out more fines for Covid breaches, 116 of them at the weekend. A third of those were students.
An unnamed councillor in Tameside was among those who has been fined although it was later revoked as it had been 'issued in error', according to the council.
Greater Manchester Police has confirmed it has started an investigation into reports that a man had travelled to and from Spain despite allegedly displaying symptoms.
The man, who has not been named, is believed to be from Heywood in Rochdale, which has registered 919 positive coronavirus cases in the last week, a rise of 29 per cent on the week before.
A statement from GMP said: "On Sunday 11 October 2020, police received a report that a man had allegedly breached Covid-19 restrictions by travelling to and from Spain via Manchester Airport whilst displaying symptoms linked to Covid-19.
"An investigation is underway."
Anyone with information is asked to contact GMP on 101 quoting incident number 3162 of 11/10/2020. Details can be passed on anonymously to Crimestoppers on 0800 555 111.
