Q fever, an unrecognized zoonosis – A la une

10 mars 2023

Among the many zoonoses, Q fever is still little known. However, it can, in some cases, be serious. Presentation.

Caused by bacteria Coxiella burnetii, Q fever is an infectious disease that affects many animal species, including cows, sheep and goats, as well as some birds and arthropods. But it is indeed a zoonosis, that is to say that it can be transmitted to humans.

How is Q fever caught? In humans, this infection occurs mainly as a result of “the inhalation of dust contaminated with bacteria present in the placenta and bird droppings or feces of infected animals”describes the European Food Safety Authority (EFSA). “Other modes of transmission, such as contaminated water or infected arthropod feces, are rare. »

What symptoms? This disease “may induce flu-like symptoms, including fever and headache, diarrhea and vomiting”, continues EFSA. “In some severe cases, it can cause pneumonia and hepatitis. » Finally, “Q fever can become chronic, if the infection lasts more than 6 months”.

Learn regarding the strains of bacteria

There are many strains of Coxiella burnetii. This is why the Sophia Antipolis laboratory of the National Health Security Agency (ANSES) took part in a vast genetic analysis. Published in November 2022 in the journal Frontiers in Microbiology, this work constitutes the largest genetic analysis in the world for this pathogen: 75 genomes have been sequenced, including 65 new ones. “The comparison of the genomes of bacterial strains made it possible to obtain its pangenome, that is to say the parts of the genome common to all strains”says ANSES.

The researchers wish to continue this work to “in particular to have strains of Coxiella burnetii isolated from patients and from farms in the same geographical area”continues the agency. “This will make it possible to better understand the transmission scenarios and the risks of exposure, to quickly detect certain hyper-virulent or hyper-disseminable strains, and, if necessary, to trace the origin of a possible epidemic. »