Serological and PCR-based prevalence of Coxiella burnetii in free-living goats of the island of Gran Canaria

Abstract

This study investigates the seroprevalence and carrier status of Q fever in wild goats on Gran Canaria, using molecular techniques to detect Coxiella burnetii in blood samples, fecal matter and reproductive tracts, to understand their possible role as carriers and shedders of this pathogen, due to the zoonotic risk involved. Q fever, caused by the gram-negative bacterium C. burnetii, is a zoonotic disease with significant public health implications. This research addresses the need for data on the prevalence of this pathogen in the island's wild goat population, given the lack of existing information. Seventy wild goats were sampled from five different locations: Güi-güí, Inagua, Riscos de Tirajana, Tamadaba, and Tasartico. Diagnostic tests included ELISA for serological analysis and quantitative PCR (qPCR) to detect bacterial DNA in vaginal swabs and feces. Results showed varying prevalence of Q fever across locations, with the highest seropositivity detected in Güi-güí and Inagua. Güi-güí had 12.5% (n=3) seropositive goats, while Inagua had 9.1% (n=2) seropositive. qPCR results from vaginal swabs revealed positivity rates of 4.2% (n=1) in Güi-güí and 18.2% (n=4) in Inagua. Fecal qPCR results indicated that 18.2% (n=4) of goats in Inagua were positive, while other locations had lower or undetectable levels of C. burnetii. The age distribution of the sampled goats ranged from 10-15 days to 6 years, with the highest number of samples from 2-year-old goats (30%; n=21). Clinical signs varied, with some goats showing symptoms such as apathy and mucopurulent nasal discharge, while the majority appeared clinically healthy. The study concludes that Q fever is present in the wild goat population on Gran Canaria, with significant variations in prevalence depending on geographic location. These findings underscore the importance of continuous surveillance and the implementation of control measures to prevent potential outbreaks and transmission to humans. Further research is recommended to understand the dynamics of C. burnetii infection and to develop effective strategies for disease management in wild ruminants.