Since September, 25 cases of the disease have been reported in the Nordic country, with 12 in December alone.
The disease spreads through airborne particles from bird poo and can be carried by Parakeets, a popular household pet in the UK.
The UK already sees between 25 and 50 confirmed cases in England and Wales a year.
Speaking to The Telegraph, Prof Paul Hunter at the University of East Anglia, said “human to human transmission may be more common than previously thought.”
He said there had been an increase since 2016, which could also be caused by better testing.
The flu-like disease, psittacosis, is a respitary disease that can lead to severe pnuemonia and meningitis.
It also poses a significant risk to unborn children, with an 80 per cent risk in foetal mortality and an eight per cent risk in maternal mortality.
It also leads to the death of 90 per cent of infected young birds.
The disease, caused by a bacteria called Chlamydophila psittaci, mainly jumps from birds to humans via airborne particles from infected wild bird poo.
Out of 45 cases recorded in Sweden earlier this year, 28 were reportedly caused by handling of poultry, caged birds, or bird feeders, according to Swedish public health officials.
A 2022 paper in the Lancet journal called the potential increase of the disease “an emerging public health risk to medical workers and other close contacts”.
Infections have been recorded in eight regions of Sweden, including Västra Götaland and Kalmar.
While the parakeets present in London aren’t thought to be more biologicaly susceptable to the disease more than other birds, it is their proximity to humans which could make them dangerous.
The ‘posh pigeons’ are a household pet and also the UK’s only wild species of parrot.
The are rumoured to have been released into the UK by rockstar Jimi Hendrix in 1966, nearly 150,000 have been imported into Europe until 2007.
In 2019, a four-year-old boy killed a parakeet in Hertfordshire and enraged animal lovers who condemned his father for glorifying killing.
The dad wrote: “With a little excitement and a steady helping hand from me, we lined up on the one at the front. As I called ‘now’, bang! And the parakeet was history.”