Professor Luke O'Neill says we will get back to a pre-COVID world - but it will take time.

The leading immunologist says it's important there is some 'optimism' in the dialogue around the virus.

He was speaking as six-weeks of level five restrictions come into effect across Ireland today.

Speaking on The Pat Kenny Show, Professor O'Neill said today particularly he, like everyone, is praying for a return to normality.

He said: “Of course we’ll get back to a pre-COVID world… it will take time though, remember.

“This six weeks is tough enough… it’s going to be six months of hard graft, let’s put it that way."

“We get to March-April next year, and let’s keep our fingers crossed the vaccines begin to roll out. They will still take time though… it’s not like a light switch… it will take months to roll out."

Professor O'Neill said early next year we could also start seeing the roll out of effective therapies for coronavirus, alongside the possible first doses of a vaccine.

He said that would allow Governments to to start relaxing some of the restrictions that have been in place throughout the year.

However, he cautioned: “Batten down, because it is going to take quite a while to get back to the way things were before."

Long-haul flights

Professor O'Neill also spoke about one of two recent studies which looked into whether coronavirus can spread during long-haul flights.

One of the studies - carried out by Vietnamese and Australian researchers and published in a CDC journal - looked at a 10-hour flight between London and Hanoi, which had 217 people on board.

Professor O'Neill explained: "One of them was infected, and 16 got infected from that person.

"The person was in business class, and 12 people were in business - so they were in proximity. The rest were in economy, and one crew member got infected as well.

“Someone got on board with symptoms, basically, and didn’t tell anybody… very mild symptoms.

“It just shows you can pick up infections on these long haul flights."

Professor O'Neill explained that it's believed the crew member picked up the virus from the business class toilets, as crew also use those facilities.

He said the whole study is a good example of track and trace - figuring out where an outbreak originated from.

However, he noted: "The [infected person's] temperature was checked on the way in, and it wasn’t elevated - it just shows you the temperature check isn’t necessarily a good indication."