Flu cases in Sweden have doubled every week since mid-November, driven by the new K variant of the influenza virus. The Public Health Agency reports a rapid increase, with cases rising from 403 to 808 in one week. Severe cases, including deaths and intensive care admissions, have also risen from low levels.
Influenza is spreading rapidly in Sweden. According to the Public Health Agency, the number of reported flu cases has doubled every week since the epidemic began in mid-November. Two weeks ago, 403 cases were reported, rising to 808 last week.
Epidemiologist AnnaSara Carnahan at the Public Health Agency describes the development: 'We see that we are in a rapid increase. We also see an increase in severe cases, but it is increasing from low levels.' The spread is mainly driven by the newly discovered K variant of the influenza A virus H3N2.
Severe outcomes have also increased. The number of deaths rose from 5 two weeks ago to 14 last week. Intensive care admissions increased from 7 to 12 during the same period.
The vaccine's protection against the K variant is unclear, but Carnahan expects protection against severe disease: 'There are indications that the protection could be a bit lower, but there is also data from England that shows moderate protection.' In the UK, masks outdoors have been recommended, but no similar advice exists in Sweden.
Carnahan notes similarities to previous years: 'It is very common for influenza to increase now. But we will see if it peaks now in December or later in the season.' She adds: 'There is nothing to say that it will decrease now before the Christmas break.' Meanwhile, the season for winter vomiting disease has started.
