Video report by ITV News Meridian's Kerry Swain
The first volunteers in the South have been given a third Covid vaccine in a new trial to see if it could give long-term protection against the virus.
It is being led by University Hospital Southampton and is the first in the world to see how effective a 'booster' vaccine would be in fighting the disease.
The results will help to shape the UK's vaccine rollout.
Kate has given nearly 40 years service to the NHS and on Wednesday (2 June) she became the first guinea pig to receive the booster jab at a community centre that houses the new Portsmouth Research Hub.
She said: "It's an important research project to do because nobody knows whether we need boosters and this could give us some answers."
This is the first study of its kind in the world, where nearly 3,000 volunteers will receive a third dose of one of seven Covid vaccines.
Dr Alexander Hicks, a Consultant Respiratory Physician said: "We know that people are a lot safer once they've had their two vaccinations but we want to know how long that last for and whether people will need a booster dose later on in the year.
"We may find that you don't need that booster dose and that's wonderful and that would be great news but also we will know the answer definitively as to whether you will need something further going into this winter and next winter and years to come."
The Cov-Boost trial is being carried out at 18 sites including Portsmouth, Southampton, Bournemouth and Oxford.
Volunteers will be monitored for a year, with regular blood tests to monitor their immune response.
One of the study's volunteers, Robin, said: "I work in a nursing home in Portsmouth so we were lucky to get our vaccinations very early and we've been hearing about how there might be another dose, there might be a booster in the autumn and it seemed like a chance to do something to try and work out if that's the right thing to do."
While another volunteer, Claire, said: "I think it would be wrong to say there's never any doubt about anything like this, but I think that I had the first two vaccines, I didn't have any adverse side effects and I'm hopeful that it will be the same way this time"
Volunteers must be over 30 and have been fully vaccinated before the start of April.
Full details of the trial can be found here with initial findings expected in September.