Q fever on dairy sheep and goat farms: Kinetics of the infection, study of the viability and genotypes of Coxiella burnetii, and effect on the quality of derivatives

  • Financing: INIA (National Institute for Agricultural and Food Research and Technology) – RTA2013-00051-C02-01
  • Head researcher: Ana L García-Pérez
  • Implementation: 2014-2017

In this project, we will study the presence and viability of C. burnetii in cheeses from sheep and goat farms which have had Q fever. Moreover, we have few studies on variants of C. burnetii in circulation in our country and whether all of the genotypes present in small ruminants are capable of producing disease in the human population, as a result of which another objective of this coordinated project is to examine the differences of strains in sheep and goats, and their relationship with the strains detected in human patients.

The specific objectives are:

1. Updating the distribution of C. burnetii on small ruminant dairy farms. We will carry out surveillance and monitoring of the kinetics of infection on sheep and goat farms throughout the project. We will carry out a comparison of the infection status in relation to animal species, the type of management, the type of operation and facilities and the control measures taken. In this way, we will learn which of these two species presents a potentially greater risk. A selection of animal and environmental samples which are positive to C. burnetii PCR will be processed for a study on viability and the genotypes present (sub-project 02). To analyse and evaluate the results, we will take into account whether the herds have an established vaccination programme against Q fever or if they have carried out antibiotic treatment, as a result of which we will know to what extent it will affect changes in circulating genotypes and the viability of C. burnetii.

2. To study the presence and viability of C. burnetii throughout the manufacturing and ripening process of cheeses. We will select farms with a positive result to C. burnetii in the milk in the tank whose production objective is unpasteurised raw milk cheese. We will monitor the cheeses throughout the ripening process to see to what degree C. burnetii is detected and, if it is present, study its viability (sub-project 02).