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Coxiella burnetii is a multi-host bacterium of major public and animal health concern. This pathogen circulates among several wild species in the Iberian Peninsula, however, the role of the Iberian lynx (Lynx pardinus) in the epidemiology of this emerging pathogen is still unknown. The objective of this work was to assess the circulation of C. burnetii in Iberian lynx populations from the Iberian Peninsula and to study the molecular characterisation of this pathogen in lynxes and their feeding ticks. A total of 922 lynxes, including free-ranging and captive individuals, were sampled between 2010 and 2022 for the collection of sera (n = 543), spleen samples (n = 390) and ticks (n = 357 from 61 lynxes). The overall seroprevalence was 7.7 % (42/543; 95 %CI: 5.5-10.0 %), with age being significantly associated with the C. burnetii exposure in free-ranging lynxes. A longitudinal study was also carried out to assess the dynamics of the circulation of C. burnetii in this wild host, revealing that 7 of the 37 longitudinally surveyed individuals seroconverted during the study period. The PCR prevalence was 4.4 % (17/390, 95 %CI: 2.3-6.4 %) for spleen samples and 1.1 % (4/357; 95 % CI: 0.0-2.2) in ticks. This is the first study to evaluate the circulation of C. burnetii in the Iberian lynx and to confirm the infection in this felid. The results obtained show a moderate, wide, homogeneous, and endemic circulation of this bacterium in the Iberian lynx populations., Competing Interests: Declaration of Competing Interest None of the authors of this study has a financial or personal relationship with other people or organizations that could inappropriately influence or bias the content of the paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Tuberculosis (TB) in deer is a serious zoonotic disease of worldwide distribution. Detection of infected animals is usually performed using single or comparative skin-testing (SST/CST), although false responses due to sensitization to other mycobacteria may occur, hampering diagnostic specificity. We describe the evolution of the responses to the SST, CST and to an in-house serological assay in a red deer farm subjected to regular TB testing in southern Spain in an attempt to understand the dynamics of possible non-specific reactions occurring under field conditions. We performed 2288 skin-tests and ELISAs in nine sampling periods between May 2009 and January 2011. In May 2010, a strong increase in skin fold thickness in response to avian purified protein derivative (PPD) (mean=4.0mm, 95% CI=3.5-4.5) and bovine PPD (mean=1.8mm, 95% CI=1.6-2.0) was observed in yearling deer hinds (n=150), compared to values recorded for the same individuals in November 2009 (avian PPD: mean=0.7 mm, 95% CI=0.6-0.8 and bovine PPD: mean=0.7 mm, 95% CI=0.6-0.7) and in January 2011 (avian PPD: mean=2.2mm, 95% CI=1.9-2.4 and bovine PPD: mean=1.1mm, 95% CI=1.0-1.2). Using SST, 54 animals (36%) of the yearlings tested in May 2010 would have been classified as positive reactors, while none of them was positive in the CST. The five animals with highest skin fold increases to mycobacterial antigens were culled and subjected to post-mortem analysis, which confirmed the absence of Mycobacterium tuberculosis complex (MTBC) infection but demonstrated the presence of environmental mycobacteria and closely related bacteria in four out of the five analyzed animals. Our results demonstrated how non-specific responses to mycobacterial antigens can adversely affect the specificity of TB diagnosis based on the SST. Thus, once TB infection has been ruled out using confirmatory techniques, application of comparative diagnostic tests is highly advisable to maximize test specificity and avoid the slaughter of false positive reactors., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Caprine tuberculosis in Spain is mainly caused by Mycobacterium caprae although the progression of the disease and lesion severity is similar to that caused by Mycobacterium bovis. In this study, the sensitivity of the gamma-interferon (IFN-γ) assay using an antigen cocktail containing early secretory antigenic target-6kDa (ESAT-6) and culture filtrate protein 10 (CFP-10) peptides for stimulation was determined and compared with those obtained in single intradermal tuberculin (SIT) and single intradermal cervical comparative tuberculin (SICCT) tests and IFN-γ assay using purified protein derivative (PPD) in three different flocks infected with M. caprae under different epidemiological conditions. Correlation between specific IFN-γ production and severity of lesions was also evaluated. Sensitivities of the diagnostic tests varied greatly in the three flocks studied, with higher values in those where higher lesion scores were observed. The results show that IFN-γ assay applied in goats using PPD or the ESAT-6/CFP-10 peptides cocktail for stimulation yielded similar sensitivity values. A significant yet weak positive correlation between specific IFN-γ production and lesion scores was detected after the stimulation with PPDs (p=0.004) whereas when the blood samples were stimulated with ESAT-6/CFP-10 peptides, the correlation was not significant (p>0.05). Therefore, specific-IFN-γ production after the stimulation with PPDs or ESAT-6/CFP-10 was not an accurate indicator of lesion severity in naturally tuberculosis infected goats with M. caprae., (© 2011 Elsevier B.V. All rights reserved.)

Red deer (Cervus elaphus) have a pronounced seasonality in their physiology. The aim of this study was to assess the effect of the season on red deer responsiveness to skin testing with the phytohaemagglutinin (PHA) mitogen. Study subjects included 270 farmed adult red deer (19 stags and 251 hinds). The skin testing was carried out between January 2009 and August 2010. The animals were injected intradermally with a 0.1 ml volume containing 250 μg of PHA diluted in phosphate buffered saline. The skinfold thickness was measured immediately prior to injection and 72 h after administration, always by the same person and with three repeats per measurement. Single effects of sex and time on skin test responsiveness were significant (p < 0.001) as well as their interaction (p < 0.001). In winter (January), and considering the average of two years, the skinfold increase in response to the intradermal injection of 250 μg PHA was 2.1 times larger in stags and 1.4 times in hinds than in summer (August). While stags had 1.3 times larger responses than hinds in winter, the inverse occurred in summer, with 1.1 times larger responses in hinds. We also evidenced a limited inter-annual variation of skinfold increase in response to PHA in red deer. These findings have important consequences regarding the interpretation of skin test results in the ante-mortem diagnosis of tuberculosis and paratuberculosis, at least in deer., (Copyright © 2011 Elsevier B.V. All rights reserved.)

We studied the effect of management on the responsiveness of red deer (Cervus elaphus) to skin testing with mycobacterial and non-mycobacterial antigens. We hypothesized that individuals from populations of the same species under different management conditions would have a different immune responsiveness. Deer sampled in this study included 1041 adult animals from 6 Spanish farms and 111 adult wild deer. We injected four sites of the neck with 0.1 ml bovine purified protein derivative (PPD), 0.1 ml avian PPD, 0.1 ml negative control PBS and 0.1 ml of Phytohaemagglutinin (PHA, containing 250 microg) as positive control, and measured the skin fold increase at time 72 h. Bovine PPD reactors were identified in 5 of 6 farms and among wild deer. Apparent prevalence among wild deer (18.9%) was not significantly higher than among farmed deer (14.5%). Avian PPD reactors were found among all 7 study populations, but apparent prevalence was lower among wild deer (<1%) than among farmed deer (12.6%; p<0.001). Deer management (farmed versus wild) was identified as a key factor affecting deer skin fold thickness increase in response both to mycobacterial (bPPD and aPPD) and non-mycobacterial antigens (PHA). The differences occurred in the same sense, regardless of some interactions; farmed deer showing higher values. The PHA skin fold increase was not affected by the PPD skin test results. We propose that using PHA as a positive control may help in the interpretation of between-population differences in tuberculin responses.