Steve Bruce has insisted players should be vaccinated against COVID after Newcastle United star Karl Darlow spent four day in hospital with the virus.
Darlow has lost a stone and a half and is ruled out of the start of the new season as he battles back to fitness.
Newcastle had a vaccine drop-in bus at their training ground during pre-season to encourage their squad to get a COVID jab.
Bruce has joined Boro boss Neil Warnock in urging players and young people not to think they are immune from a debilitating bout of COVID, which can be reduced if vaccinated.

Darlow says his brush with COVID was “pretty awful” after he became dehydrated and needed hospital treatment.
Freddy Woodman will keep goal for Newcastle against West Ham on Sunday, with Darlow out and Martin Dubravka injured.
Bruce revealed: “For any young people who are not having this jab, there is a prime example.
“Karl found himself in hospital for the best part of a week, he has dropped over a stone and a half in weight. It has really knocked him around.
“I can't stress enough the importance of vaccination.
“To see a 30 year old hospitalised by it. He is young, fit, healthy and it still left him in a poorly situation. It wiped him out.
“Just because you are under 30, you are not immune to it. We have seen how sick it can make a squad.”
Bruce is blessed with a good group of keepers. Woodman, the former England U21 keeper, was on loan at Swansea last season, narrowly missing promotion.
Bruce confirmed: “Freddy will get his chance. He has waited patiently, been away the last two years.
“It is Freddy's big opportunity and I have been very impressed with what I have seen in the last week after good reports from Swansea.
“We are fortunate in that department. It is such a crucial part, the goalkeeper. We have lost a couple but have a good young player coming in.”
Darlow said this week: “I had to go to hospital which was pretty awful - but I'm slowly improving now despite still feeling a bit rough. This shows the virus is still going about and we still need to be careful with it.”