25 people – most of them in the Stockholm area – have fallen ill after being infected with a very rare Legionella bacterium. The infection is suspected to come from potting soil, according to the Public Health Agency.
Most of those infected have handled soil, says state epidemiologist Magnus Gisslén.
It was in early May that the first cases of illness caused by the Legionella longbeachae bacterium were discovered. So far, around 25 people between the ages of 45 and 83 have been affected, and many have required hospital care.
It's a serious disease that can cause severe pneumonia. Older people with underlying illnesses are at greatest risk, says Magnus Gisslén, who is a professor of infectious diseases at the Sahlgrenska Academy.
The rare bacterium occurs naturally in the soil, but it's very unusual for people to be infected in Sweden. In Australia and New Zealand, it's relatively common to be infected through gardening and soil handling.
The infection is transmitted by inhaling bacteria and getting them into the lungs.
The Public Health Agency has not yet traced the source of the ongoing outbreak, but suspects that it involves potting soil available in stores. However, the infection cannot be linked to a specific brand or purchase location.
Some of the infected are believed to have gotten the infection after contact with ordinary soil. But the risk of infection arises when bacteria in dust from soil are inhaled, and the risk is greater when opening potting soil bags than when working with soil in general, says Magnus Gisslén.
The disease is treated with antibiotics.
Magnus Gisslén emphasizes that it's important for healthcare providers to be aware of the ongoing outbreak.
There's good treatment, but it's essential to make the right diagnosis so that the patient gets the right antibiotics in time, he says.
This summer's outbreak is the largest since 2018, when around 40 people fell ill and one person died. Even then, the infection came from soil.
Sara Assarsson/TT
How to protect yourself
Public Health AgencyTT
The risk of falling ill is very small, but smokers and people with weakened immune systems or impaired lung function are more vulnerable. To protect themselves from potential infection, those who handle soil or garden compost should consider the following:
Open potting soil bags outdoors or in well-ventilated areas and avoid inhaling dust from the bags.
If the soil or compost is dry, moisten it with a watering can to reduce the risk of dust swirling up.
Wash your hands with soap and water after handling soil and compost.
