NZ flu deaths could hit historic highs as hospitalizations surge

New Zealand is heading toward a flu season unlike any in recent memory. Epidemiologist Michael Baker, watching the data accumulate through September, sees the shape of something large and troubling taking form—one that could push influenza deaths to levels the country has not seen in years, possibly decades. The evidence is already visible in the hospitals.

Hospitalization rates have climbed into what public health officials classify as "very high" territory and have stayed there for weeks. In Auckland, the numbers have reached their highest point in a decade. The severity of cases has nearly doubled: this year's peak for severe acute respiratory infections caused by influenza stood at 9.5 cases per 100,000 people, compared to 4.3 per 100,000 last year. That gap—from 4.3 to 9.5—is not a marginal shift. It is a signal that far more people are becoming seriously ill.

Baker explains the arithmetic that follows from these numbers. On average, influenza kills about 500 New Zealanders annually, though arriving at that figure is more complicated than it first appears. Death certificates do not always capture the full story of how flu kills. A person might die of a heart attack, but that heart attack might never have occurred without the influenza infection that weakened them. The disease acts as a trigger, a final push that tips someone already fragile over the edge. Modelling is required to account for these hidden deaths, the ones that would not exist without the flu but are recorded under a different cause.

Given how many people have been infected this year—far more than usual—and given that a consistent proportion of the seriously ill will die, the mathematics point toward a year that breaks the historical pattern. "It's speculation," Baker said, "but it has been such a severe influenza season based on hospitalisations we're almost certainly going to be at the upper end of the historic range." He cannot say with certainty until the year closes and the final counts are tallied. But the trajectory is clear enough to warrant the warning.

What made this season so severe remains partly a question of timing and exposure. More people got infected, which meant more people became seriously ill, which meant more deaths. The data from calls to the health advice line and from hospital admissions both pointed to the same conclusion: the virus was circulating widely and hitting hard.

There are small reasons for cautious hope embedded in the response. The government made flu vaccines free this year for the most vulnerable groups—the elderly, the immunocompromised, those with chronic conditions. Baker credits this decision with saving lives. Without it, the death toll would almost certainly be higher. In the past two weeks, hospitalization rates have begun to fall among the general population, suggesting the peak may have passed, though the full human cost of the season will not be known for months.

Baker has also identified a gap in how New Zealand prepares for and communicates about flu outbreaks. When the next major outbreak arrives—and it will—he wants to see health authorities speak more clearly and more often about the actual risks and what people can do to protect themselves. The warning system exists. The data exists. What is sometimes missing is the voice that translates those numbers into something the public understands and acts on. For now, the 2026 flu season continues its course, and New Zealand waits to see where the final numbers land.