More than 23,000 people aged between 18 and 29 have had a jab in three weeks since the coronavirus vaccination programme was opened up to those in their twenties.
Yet the number of new coronavirus cases is continuing to rise with nearly 400 positive tests confirmed in the last week.
That is higher than it was at the beginning of April with the vast majority in younger age groups.
Northampton, East Northamptonshire and Daventry have all seen sharp rises in new cases during the last few days, according to data on the government daily dashboard.
County centres and clinics began offering drop-in sessions — which will continue seven days a week at the Moulton Park centre in a bid to meet its target of offering a first jab to all adults by July 19.
Latest official figures show 497,749 Northamptonshire folk have received at least one dose by Saturday.
Of those, 358,841 have had both doses — more than 54 percent of all the county's adults.
Chris Pallot, director of the county's vaccination programme, said: “Over the past few days we’ve been really pleased to welcome hundreds of people taking advantage of the first opportunities to get their first dose of the Moderna vaccine without an appointment at our Vaccination Centre.
“Now that the vaccination programme is open to everyone aged 18 and above, we want to continue to offer the flexibility of daily drop-in sessions in addition to the usual bookable appointments. We’re therefore delighted to confirm that drop-ins for first appointments will be extended at Moulton Park through to Sunday July 18.
“Vaccination is our best protection against coronavirus and our pathway back to normal life – so if you’ve not yet had your first dose then please do take advantage of these extra opportunities to get the jab.
“We’re also reminding people aged 40 and over who had their first dose eight weeks ago or more that they are now eligible to have their second dose now, and they can book or rebook their appointments by visiting the NHS website, calling 119 or contacting their GP practice.”
Latest NHS figures showed three Covid-19 patients being treated in Northamptonshire's two acute hospitals at Northampton and Kettering, including one in critical care requiring ventilation.
At the beginning of June, hospital staff were treating zero patients with Covid.
Northampton's public health director, Lucy Wightman, insisted the proportion of younger people testing positive underlined the need to speed up the vaccine rollout.
She said: "Getting fully vaccinated is the single most important thing we can do to protect ourselves, our loved ones and our communities against coronavirus, so it’s vital that everyone who is eligible should come forward for both doses as soon as they are invited.
“When people are outside and physically distanced from each other, the particles containing the virus that causes Covid-19 are blown away which makes it less likely that they will be breathed in by another person but it is still important to keep a safe distance from people you don’t live with.
“If you do meet inside, also keep your distance and make sure the space is well ventilated. Bringing fresh air into a room and removing older stale air reduces the chance of spreading Covid-19.
“If you are going to the cinema, out for the day or evening, meeting a group of friends and family or playing a team sport, you need to take a lateral flow test beforehand.
"We are all still in this together, so we need to get tested twice a week and not let each other down. If we leave the house and mix with others, then we need to make sure we are not unwittingly spreading the virus.”
■ Anyone with Covid-19 symptoms — a new, continuous cough, high temperature, or loss or change in sense of taste — should immediately self-isolate and book a PCR test online HERE or by calling 119.
■ Anyone aged 18 or over is eligible for a Covid-19 vaccination — book online HERE any time or call 119 free between 7am and 11pm, seven days a week. You can turn up without an appointment at Moulton Park Vaccination Centre any day between 5.30pm and 7.30pm.