Smittsam sjukdom gör att fåglar dör i massor – uppmaningen: “Sluta mata” – nkp.se

Swedish veterinary authorities have issued an urgent advisory to the public to stop feeding wild birds following an unprecedented outbreak of a contagious disease that is causing mass mortality among songbird populations. The outbreak has been particularly severe among blue tits, leading to a noticeable decline in bird activity across residential gardens and public parks.

The scale of the current event has drawn significant concern from national health and veterinary experts. According to reporting from SVT Nyheter, the state veterinarian has indicated that the severity and spread of this specific outbreak are without precedent in recent observations, stating that they have never seen an outbreak like this.

The disease identified in these cases is trichomonosis, caused by the protozoan parasite Trichomonas gallinae. This pathogen primarily affects the upper digestive tract of birds, creating necrotic, yellowish plaques in the throat and esophagus. These lesions eventually obstruct the bird’s ability to swallow, leading to death by starvation or secondary infections.

The Role of Bird Feeders in Transmission

Central to the veterinary advisory is the directive for citizens to cease bird feeding immediately. While providing food is generally viewed as a wellness practice for wildlife, during an active outbreak of trichomonosis, bird feeders become primary vectors for the disease.

The parasite is transmitted through direct contact or through contaminated surfaces. When infected birds visit a feeder, they leave behind saliva and mucus on the perches and the seeds themselves. Healthy birds then ingest the parasite when they feed at the same location, creating a concentrated point of infection that accelerates the spread throughout the local population.

Reporting from nkp.se emphasizes that the plea to stop feeding is a strategic measure to break the transmission cycle. By removing the artificial gathering points, authorities aim to reduce the frequency of bird-to-bird contact, thereby slowing the rate of new infections.

Ecological Impact in Urban Areas

The impact of the disease is already evident in urban environments. In Uppsala, local observations detailed in UNT describe a disturbing silence in parks and gardens where the song of the blue tit has effectively vanished. The loss of these birds is not only a matter of local biodiversity but also affects the urban ecosystem, as blue tits play a critical role in controlling insect populations.

The vulnerability of the blue tit suggests a high susceptibility within this specific species during the current cycle. While other birds, such as goldfinches, are also known to be affected by Trichomonas gallinae, the current concentration of deaths among tits has made this outbreak particularly visible to the public.

Veterinary and Public Health Context

Trichomonosis is not known to be a zoonotic disease, meaning it does not pose a direct infection risk to humans. However, the mass death of wildlife is monitored closely by public health and veterinary agencies as an indicator of environmental health and the potential for other, more dangerous pathogens to emerge or spread within stressed populations.

Veterinary experts note that the spread of such parasites can be exacerbated by several factors, including weather patterns and the density of bird populations in urban areas. When birds are forced into smaller areas or rely heavily on a few food sources, the probability of transmission increases exponentially.

For those who wish to support wildlife without contributing to the spread of the disease, experts suggest focusing on providing safe habitats, such as planting native shrubs and trees that provide natural food sources, which do not facilitate the same level of concentrated contact as commercial feeders.

As of May 9, 2026, the recommendation to avoid feeding remains the primary intervention strategy. Authorities continue to monitor the situation to determine if the outbreak will subside naturally as the population reaches a threshold of immunity or if further interventions are required to protect the remaining songbird populations in Sweden.