Harris, known to friends as "Harry", was part of the expert team who successfully saved all 13 members of the soccer team, who were trapped inside the cave for 17 days after heavy rain caused the cave system to flood.
All the rescued boys and their coach were taken to a hospital in the nearby city of Chiang Rai.
"They (all the boys) will have to stay in the hospital for one week to wait for their results and to see if anything changes", he said.
FOUR more boys have been brought out of a flooded cave in northern Thailand as the daring rescue operation ended for the second day.
The mission to save the last 4 members of a Thai soccer team and their coach, who have been trapped in a cave for more than two weeks, has begun. "All the thirteen Wild Boars are now out of the cave", the Thai navy SEALs team, which is helping to lead the operation, said on its Facebook page. "We will check later today whether their eyes have adjusted to light", said Dr Jesada.
Thai Navy SEALS divers have already rescued eight of the boys.
Four boys and their 25-year-old football coach "will be extracted on Tuesday".
Technology billionaire Elon Musk went into the cave on Monday and left the rescue team with a "kid-sized" submarine his company SpaceX had built, Thailand's interior Minister Anupong Paochinda said.
Thongchai Lertwilairattanapong, Inspector General of the Public Health Ministry, said the first four boys taken out on Sunday were eating normal and plain food.
"Potentially deadly histoplasmosis - a lung infection also known as "cave disease" and "spelunker's lung" caused by breathing in spores from animal waste - is one of several illnesses that medical experts are anxious the 12 boys and their coach could have contracted while trapped deep in the subterranean system". They did get a treat, however: bread with chocolate spread that they'd requested.
Four boys and the coach are still trapped deep inside, and authorities have indicated they're continuing with their so-far successful effort to bring the boys out guided by experienced divers. We wish them a speedy recovery.
But he added rescuers may need more than 20 hours, to replan and replenish oxygen supplies, to be ready to mount the next mission.
"The kids are footballers, are strong and have high immunity", Jesada said when asked why they survived so long.
Governor Narongsak Osottanakorn, who is leading the rescue mission, also warned today's operation could be more hard due to the increased number of people to be evacuated, but that he expected the "everyone will be out today".
Soccer's governing body, FIFA, has invited the boys to the World Cup final in Moscow on Sunday if they're well enough to attend.