Diagnosis, prevention and control of diseases caused by Chlamydia in small ruminants. Review

Abstract

The species that make up the genus Chlamydia affect a wide range of animal hosts, causing various pathologies. Chlamydia abortus (C. abortus), Chlamydia psittaci (C. psittaci) and Chlamydia pecorum (C. pecorum) are the most clinically relevant in small ruminants worldwide, since they have been related to reproductive, ocular and digestive tract problems respectively; two of these (C. abortus and C. psittaci) represent a potential zoonotic risk to humans. The diagnosis of infections by organisms of this genus is complicated; since, in most cases, there are no clinical signs that indicate the presence of the agent in affected animals. Currently, in European countries, the prevention and control mainly of C. abortus is carried out through the administration of commercial attenuated immunogens; however, their use has not shown satisfactory results in the protection of susceptible animals. Therefore, the implementation of new immunization options based on the utilization of recombinant proteins is the line of research that is currently taking the most prominence. Additionally, the use of proteins with immunogenic potential could be important tools for the diagnosis, prevention and control of these pathogens. Due to this, the present review focused on recapitulating the most current studies focused on the experimental use of different immunogenic proteins of Chlamydia spp. used worldwide, highlighting their innovation and results obtained in experimental models.