Denmark has experienced an increase in Legionnaires’ disease in recent years, according to new figures from the national serum institute, Statens Seruminstitut (SSI).

Last year, there were 157 registered cases of Legionnaires’ disease in Denmark – an increase of 24 percent compared to 2013. Most cases were registered in Region Syddanmark.

“The rise is quite notable,” Søren Uldum, a senior researcher with SSI, told DR Nyheder. “Last year we had the highest number of Legionnaires’ disease cases ever registered in Denmark.”

“We are looking into the reason for the increase and if there is a reason for so many cases in the southern region of the country.”

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Weather to blame?
Legionnaires’ disease resembles influenza at first, but the consequences are more serious and about 15 percent of those infected end up not surviving.

The Legionella bacteria that causes the disease lives in fresh water and other moist environments. Most people become infected because the bacteria lives in the water they drink or bathe in.

The disease spreads quickly when the water is 25-45 degrees in temperature and SSI is looking into whether there is a connection between the wet Danish summer and the increase in cases.

“We know from cases abroad that a warm and moist summer means more Legionnaire cases,” said Uldum, who also underlined there was no need for concern due to the rise.

“Legionnaire’s is still a rare disease, so there is nothing to be worried about.”