Flu cases surge across Croatia

Croatia is experiencing a significantly earlier and stronger influenza season than usual, according to the latest data from the Croatian Institute of Public Health (HZJZ).

By 28 December 2025, a total of 29,771 flu cases had been reported nationwide since the start of the 2025/2026 flu season.

Of these, 5,051 cases were recorded in the most recent week alone, RTL reported.

HZJZ notes that the slight decline in weekly notifications compared to the previous week is likely due to fewer working days during the holiday period, rather than an actual reduction in flu activity.

Flu cases have been reported in all Croatian counties, with the highest incidence rates per 100,000 inhabitants in the past week recorded in Varaždin County and Krapina-Zagorje County.

As seen in previous seasons, pre-school and school-aged children account for the largest proportion of reported cases. In contrast, the lowest incidence rate has been observed among those aged 65 and over, although this group remains at higher risk of severe complications.

This flu season stands out due to its exceptionally early rise in cases. Since October, nearly 30,000 infections have been reported, compared with just 667 cases during the same period last season.

Health authorities say this sharp increase highlights the intensity of the current flu wave and the importance of monitoring vulnerable populations.

So far this season, 950 people have been hospitalised due to influenza, with 45 patients requiring treatment in intensive care units.

For comparison, during the same point in the 2024/2025 season, 69 hospitalisations were recorded, including three ICU admissions, underscoring the severity of this year’s outbreak.

Five Flu-Related Deaths Recorded

As is typical during flu seasons, Croatia is also seeing an increase in deaths linked to influenza and its complications, particularly among older adults and people with chronic illnesses.

To date, five deaths have been officially attributed to flu-related complications during the current season.

HZJZ again emphasised that the lower number of reports in the final week of December should be interpreted with caution, as it reflects reduced reporting during the holiday period rather than a genuine decline in infections.

Health officials continue to urge vigilance, particularly among at-risk groups, as the flu season progresses into the new year.