Medsafe, New Zealand's medical regulatory body, says there have been 147 adverse reactions to COVID-19 vaccines since the rollout commenced on February 20 - but one doctor believes these cases "are not unexpected".
A report shows the most common reaction is dizziness (27 cases), headaches (21), nausea (18), and fainting (18).
Director-General of Health Dr Ashley Bloomfield says an adverse reaction is any reaction someone has to a vaccine, whether it's mild or serious.
"Of those, there were three that were considered serious. It's quite a low bar for serious. All of these involved an allergic reaction of some kind, one of which was classified as an anaphylactic reaction to the vaccine in someone who had a history of allergies," he says.
"All were managed appropriately on the spot… None of the people required hospitalisation or have had any ongoing problems."
Dr Bloomfield adds that Medsafe's assessment is that the number and pattern of adverse effects that are reported are "very much in line" with what they would expect and what's been reported overseas.
Associate Professor James Ussher, from the University of Otago's Department of Microbiology and Immunology, also says the range of adverse events is consistent with those found during clinical trials.
"To date, a staggering 689 million doses of vaccine (a substantial proportion of which is the Pfizer vaccine) have been administered globally, with ongoing monitoring of safety by regulatory agencies," he says.
"Allergic reactions to Pfizer's COVID-19 vaccine are rare but reported. Vaccinators are trained in the management of allergic reactions. As noted in the report, these reactions were appropriately managed in the clinic and did not require hospitalisation."
Dr Fran Priddy, clinical director at Vaccine Alliance Aotearoa New Zealand, says while anaphylaxis after vaccination is very rare, it is still known to occur with any vaccine.
"For both mRNA COVID-19 vaccines currently in use globally, Pfizer and Moderna, anaphylaxis does appear to be associated with vaccination, however it is still very uncommon. These cases are not unexpected, especially with a large vaccination campaign," she says.
"While anaphylaxis is serious, it is treatable. COVID-19 vaccinations are being given in settings prepared to treat anaphylaxis if it occurs.
"The fact that New Zealand is reporting adverse event information is good news, as it means that the safety follow-up systems is working transparently and the vaccination campaign is really getting underway. Good news for New Zealand."