Acute Q fever related in-hospital mortality in the Netherlands

A large outbreak of acute Q fever has been reported in the Netherlands with over 3500 cases from 2007 to 2009, during which 749 patients were hospitalised. In foreign cohorts, reported mortality rates in patients hospitalised with acute Q fever, ranged from 0.9 to 2.4%. We analysed mortality among hospitalised patients with acute Q fever in the Netherlands.

Physicians from hospitals in the afflicted region were asked to provide details about patients who died with a diagnosis of acute Q fever between 2007 and 2009.

Nine patients (seven males, median age 72 years) from six hospitals were reported, who died within approximately one month following hospitalisation for acute Q fever. Six definite acute Q fever cases and three probable cases were identified. Six patients presented with infiltrates on the chest X-ray and a median CURB-65 score of 3. Median time of hospitalisation was 13 days (range 1-33). All patients had serious, often coinciding, underlying conditions including chronic cardiovascular disease, chronic lung disease, diabetes mellitus and malignancy.

The mortality rate of patients hospitalised because of acute Q fever was estimated at approximately 1%. Patients who died with acute Q fever were often male, of older age, and had chronic coinciding underlying conditions, which gives an a priori higher risk of death.