Increased mortality due to Q-fever complications
The years 2007 to 2010 saw the largest Q-fever outbreak ever. An estimated 45,000 people were infected, mainly inhabitants of Eastern Brabant.
The disease is transmitted from goats to humans. Until now, little was known about the long-term consequences of this outbreak. Between 1 and 5 percent developed a chronic form of Q-fever, in 60 percent of whom complications occurred. A quarter of these patients died within 3 years as a result of the infection. These results have been reported by Sonja van Roeden of the University Medical Center (UMC) Utrecht, who obtained her PhD this week.
Q-fever is caused by the Coxiella burnetii bacterium, which transmits the disease to humans and animals worldwide. Research physician Sonja van Roeden carried out her research at the UMC Utrecht and the Jeroen Bosch Hospital in 's-Hertogenbosch. Using the national chronic Q-fever database, she analyzed the data of 439 adults who had developed a chronic form of the disease during this outbreak.
Relatively high mortality
By the end of 2016, 74 patients had already died in the Netherlands as a result of Q-fever contracted during the 2007-2010 outbreak. The results also showed that elderly people with cardiovascular infections who develop complications have an increased risk of dying from the infection in the long term. In addition to the risk of complications and increased mortality, 55 percent of patients with chronic Q-fever proved to suffer from a lower quality of life in the long term, mainly because they had to be treated with several antibiotics for a long period of time (at least one and a half years), the result of which is often disappointing, and because the treatment causes adverse effects in many patients.
Q-fever is caused by the Gram-negative intracellular bacterium Coxiella burnetii. In the majority of patients, the infection occurs without their noticing. However, a proportion of infected people (35-40%) show relatively mild symptoms after infection and develop acute Q-fever with symptoms such as flu-like symptoms, and occasionally pneumonia and hepatitis. In a small number of patients (1-5 percent), the bacterium remains present in the body and chronic Q-fever develops in the years after infection. In contrast to acute Q-fever, the prognosis of chronic Q-fever is less favorable: the complications are more serious and frequent and can be life-threatening.
Sonja van Roeden says, “Of the diseases that are transmitted from animals to humans, Q-fever has had the greatest impact on patients in recent Dutch history. Any suspicion of chronic Q-fever, for example in a patient with valvulitis, must be confirmed by a blood test and other means.”
Roeden's PhD: “Prognosis and treatment of chronic Q-fever”
Sonja van Roeden (Utrecht, 1988) obtained her doctoral degree on September 6, 2018 at Utrecht University for her thesis "Prognosis and treatment of chronic Q-fever." Supervisors are Prof. A.I.M. Hoepelman (Infectious Diseases Department, UMC Utrecht) en Prof. M.J.M. Bonten (Laboratory of Medical Microbiology, UMC Utrecht); Co-supervisors are Dr. J.J. Oosterheert (Infectious Diseases Department, UMC Utrecht) and Dr. P.C. Wever (Laboratory of Medical Microbiology, Jeroen Bosch Hospital, 's-Hertogenbosch). Sonja van Roeden is training to become an internist at the Diakonessenhuis in Utrecht and UMC Utrecht.