A deadly outbreak of psittacosis, a bacterial infection also known as parrot fever, has been reported to kill five people in Europe.
The World Health Organisation (WHO) shared that the infection killed four in Denmark and one in the Netherlands, with exposure to wild or domestic birds being reported in most cases.
The outbreak was initially noted in 2023 and has continued through the start of this year. Austria, Denmark, Germany, Sweden and the Netherlands have been reporting an increase in cases of psittacosis since the end of last year through the EU Early Warning and Response System (EWRS).
The affected countries conducted epidemiological investigations to identify possible exposures and clusters of cases, including testing samples from wild birds to verify the prevalence of the bacterium.
The infection is triggered by bacterium C. psittaci from the Chlamydia family and is found in a variety of wild and pet birds as well as poultry. Infected birds might not always seem sick, but they shed the bacteria when they breathe or poop.
Human infections occur mainly through contact with secretions from these infected birds and are mainly associated with those working “with pet birds, poultry workers, veterinarians, pet bird owners and gardeners in areas where C. psittaci is epizootic in the native bird population”.
The World Health Organization continues to monitor the situation. However, it assessed that currently the risk posed by this event is low based on the available information.
Denmark has recorded a significant increase in psittacosis cases from late 2023. It confirmed that 23 people tested positive for C. psittaci until 27 February 2024. However, public health officials there suspect that the case count is actually much higher, according to the WHO.
Seventeen people with parrot fever were hospitalised in Denmark, of which 15 cases developed pneumonia and four died. At least one person in Denmark got parrot fever from a pet bird.
Of the 15 other cases with available exposure information, 12 said they had contact with wild birds primarily through bird feeders. But in three of the cases, the patients had no history of contact with birds of any kind.
In the Netherlands, an increase in psittacosis cases was observed since the end of December 2023, with 21 people reporting testing positive for parrot fever until 29 February 2024.This represents twice as many cases as recorded in the same period in previous years. All recent cases were hospitalised and one patient died.
In Austria, four cases of parrot fever have been reported as of March 4 this year, but none of the patients travelled abroad and wild birds were not considered as a source of infection.
Germany saw an increase in persons testing positive for C. psittaci in December 2023 which continued up to February 20.
Finally, ten cases were reported in Sweden in January and three in February. However, this number is lower than the average number of cases reported in the same period compared to the previous five years.
