The number of searches for "winter vomiting disease" on the Vårdguiden 1177 website has now surpassed a threshold which is seen as a clear sign that the spread of the disease has gained speed. Over the next few weeks, the Public Health Agency of Sweden expects that significantly more people will catch the virus.
Norovirus, the winter vomiting disease, is very contagious and the incubation period is relatively short, between 12 and 48 hours. The main symptoms are feeling sick, vomiting, diarrhoea, stomach ache, headache and fever.
The best way to protect yourself against it is to wash your hands, at home as well as at work. Liquid soap is better than hand sanitizer.
"We use this internet-based surveillance system and look at how many people have been searching for the word vinterkräksjukan (winter vomiting disease), and we now see that the number of searches has passed the threshold that indicates that it is starting to spread in the community," Elsie Ydring, a molecular biologist at the Public Health Agency tells Radio Sweden.