An immunocompromised person said she had no option but to pretend to be getting a second Pfizer dose in order to get her third before Christmas, due to a gap in the Government's booking system.
Some immunocompromised people require three doses of the Pfizer vaccine in order to have the same level of protection the general population receive with two shots.
The third dose must be prescribed by a GP, but there is no option on Book My Vaccine to book a third primary dose – only for a first or second dose, or a booster.
A Wellington woman contacted the Herald saying she had spent several days trying to book an appointment for her third dose, or find a walk-in clinic that would see her on the spot.
"There was literally no other way than to pretend I was there for my first dose or my second," she said.
"I've been emailing my GP, he's copied in their Covid expert nurse, I've been ringing and emailing the Covid people, looking online, trying to find something there that would say it's a walk-in clinic.
"It's taken quite a lot of time and been quite bureaucratic and I've got quite frustrated.
"It's totally illogical, it doesn't make any sense."
After being unable to book online, she rang several clinics, with one telling her they were not accepting walk-ins, and another that they would not be administering the vaccine again until next year.
The woman obtained her third shot on Friday by booking another second dose, and then explaining upon arrival it was her third, and showing her prescription.
Booking a second dose through Book My Vaccine also did not trigger any alert, even though the system showed she had received two doses previously.
She was concerned the frustrating process would deter some people in her situation from getting a third dose altogether, which would put them at greater risk from Covid.
"Percentage-wise there aren't that many of us, but numbers-wise there are enough for it to be a bit of a headache," she said.
"And of course it's quite a risk for us if we don't get that third."
A Ministry of Health spokesperson said a third dose of the Covid-19 vaccine is recommended for severely immunocompromised individuals aged 12 and older.
"Individuals who are severely immunocompromised are at a higher risk of severe outcomes from Covid-19 and might not produce a sufficiently strong immune response after two doses of the Pfizer Covid-19 vaccine.
"A third primary dose may be beneficial and can be administered at least eight weeks after the second dose."
They said individuals who met the eligibility criteria could be prescribed a third dose by their GP.
"They cannot book online, but can walk into any site with a prescription from their GP or other health specialist to be vaccinated."
The spokesperson said they were sorry to hear the Wellington woman had struggled to access the third dose.
New Zealand reached its 90 per cent vaccination target last week, and MedSafe also approved the use of the Pfizer vaccine in children aged 5 – 11.