CVI seeks improved test for Q fever

The Central Veterinary Institute (CVI) of Wageningen UR in Lelystad is going to try to acquire a better perspective on various types of the bacterium Coxiella burnetii, which causes Q fever. The Institute is also going to investigate the quality of existing tests.

Q fever derives its names from the many questions (queries) about the disease when it was first described in Australia. That was more than 70 years ago, but scientists still have many questions concerning C. burnetii. 
Last week, Minister of Agriculture Gerda Verburg decided to impose a reporting obligation for Q fever. This means that owners of goats and sheep must report animals with symptoms of this disease. The most important symptom is miscarriage. Verburg  decided on this measure because in 2007 there was an outbreak of the disease near the town of Herpen in the Netherlands, where 170 people became infected. 
The infection can be transmitted to people from animals via manure or urine and possibly via raw milk. People are usually infected by inhaling dust particles which contain the bacteria. However, people cannot infect each other, as far as is known. Pregnant women appear to be highly susceptible to the disease. But there are no indications that infected women have an increased risk of miscarriage. Most people who are infected do not become ill. Approximately 40% experience flu-like symptoms. A small percentage become seriously ill due to pneumonia or liver infection.

The problem with the current tests is that it is unclear how accurate they are. There is no infection standard available with which the tests can be compared to each other. Some tests focus on the presence of antibodies in the blood, others can indicate the presence of the pathogen, and there are tests that can distinguish between various types of the bacteria.

According to researcher Hendrik Jan Roest, all tests can currently be used, but little can be said about the quality of the tests. For example, it is unknown whether they can fail to detect infections, and if they do, at what level of infection this failure occurs. The CVI is working on improving the technology on all fronts. In laboratory tests with goats and sheep, the CVI wants to determine how well the various tests work, among other things. The Institute is also using new techniques to look for different strains of the pathogen. ‘We barely know if there are various types in the Netherlands’, explains Roest. 

In the Q fever research, the CVI is working together in the Netherlands with the National Institute for Public Health and the Environment (RIVM), the Animal Health Service and VU Amsterdam. An important partner outside the Netherlands is the French food safety agency AFSSA. / Jan Braakman