New Zealand’s health ministry confirmed the nation’s first fatal COVID-19 vaccination on Aug. 30.

A female patient, whose age was undisclosed, suffered deadly complications from the Pfizer vaccine. The patient developed myocarditis, which caused heart inflammation according to Reuters.

“This is the first case in New Zealand where a death in the days following vaccination has been linked to the Pfizer COVID-19 vaccine,” the health ministry said in a statement obtained by the newswire agency.

Myocarditis is a condition that causes the heart muscle to become inflamed, limiting the organ’s ability to pump blood and causing irregular heartbeats. A recent study suggested in August these symptoms were more common among young male recipients.

Israel’s Health Ministry published a different study in June that suggested young male recipients had a high probability of developing heart inflammation. However, 95 percent of the adverse reactions were mild according to Reuters.

The country recorded 275 cases of side effects out of 5 million vaccinated people. This suggests a 0.0055 frequency rate.

Pfizer acknowledged myocarditis is a known symptom but it is extremely uncommon.

“Pfizer takes adverse events that are potentially associated with our vaccine very seriously,” the company said according to the newswire agency. “We closely monitor all such events and collect relevant information to share with worldwide regulatory authorities.”

The New Zealand health ministry claims the greater good is more important than a small number of adverse reactions and deaths. A representative claimed it was hard to know if the patient had an underlying medical condition that might have contributed to her death.

“The benefits of vaccination with the Pfizer COVID-19 vaccine continue to greatly outweigh the risk of both COVID-19 infection and vaccine side effects, including myocarditis,” the pharmaceutical giant said.

An independent panel is investigating the safety of vaccines, and claims the woman’s cause of death is rare.

Pfizer/BioNTech, Janssen, and AstraZeneca vaccines has all been tentatively approved for use. Only the Pfizer vaccine has been fully authorized for public use.

The country has been locked down since one local infection was reported on Aug. 17. New Zealand recorded 562 cases at the time of publication.