Epidemiology of Q fever in humans in four selected regions, Spain, 2016 to 2022.

BackgroundQ fever is a bacterial zoonosis caused by Coxiella burnetii. Spain has the highest number of notified human cases in Europe. Small ruminants are a key reservoir for the pathogen, transmission from animals to humans is usually airborne.AimWe aimed at exploring temporal and spatial epidemiological patterns of sporadic and outbreak cases of Q fever in four Spanish regions with the highest number of notified cases.MethodsWe extracted data on Q fever cases in the Canary Islands, Basque Country, La Rioja and Navarre between 2016 and 2022 from the Spanish National Epidemiological Surveillance Network. We calculated standardised incidence ratios (SIR), spatial relative risks (sRR) and posterior probabilities (PP) utilising Besag-York-Mollié models.ResultsThere were 1,059 notifications, with a predominance of males aged 30-60 years. In Basque Country, La Rioja and Navarre area, 11 outbreaks were reported, while no in the Canary Islands. A seasonal increase in incidence rates was observed between March and June. In the Canary Islands, elevated sRR was seen in La Palma, Gran Canaria, Lanzarote and Fuerteventura. In Basque Country, La Rioja and Navarre area, the highest sRR was identified in the south of Biscay province.ConclusionGoats were the main source for humans in outbreaks reported in the literature. Seasonal increase may be related to the parturition season of small ruminants and specific environmental conditions. Local variations in sRR within these regions likely result from diverse environmental factors. Future One Health-oriented studies are essential to deepen our understanding of Q fever epidemiology.

Acute Q fever pneumonia diagnosed by metagenomic next-generation sequencing.

INTRODUCTION: Q fever, a zoonotic disease caused by Coxiella burnetii (C. burnetii), presents diagnostic challenges due to its clinical and radiological nonspecificity, which often mimics community-acquired pneumonia, coupled with the limitations of traditional diagnostic methods. Metagenomic next-generation sequencing (mNGS) has become an indispensable tool in clinical diagnostics for its high-throughput pathogen identification capabilities. Herein, we detail a case of acute Q fever pneumonia diagnosed with mNGS. CASE PRESENTATION: The patient exhibited symptoms of fever, cough, expectoration, and diarrhea for three days, with the pathogen undetected in initial laboratory assessments. Bronchoscopy and bronchoalveolar lavage (BAL) were conducted, leading to the identification of C. burnetii in the lavage fluid via mNGS. Consequently, the patient was promptly initiated on a treatment regimen of 100 mg doxycycline, administered orally every 12 hours. RESULTS: Post-treatment, the patient's temperature normalized, and a full recovery was observed. The follow-up chest CT scan revealed complete resolution of the right lower lobe consolidation. CONCLUSIONS: The clinical presentation of Q fever pneumonia lacks specificity, making diagnosis based solely on symptoms and imaging challenging. mNGS offers a superior alternative for identifying elusive or rarely cultured pathogens.

Tick abundance and infection with three zoonotic bacteria are heterogeneous in a Belgian peri-urban forest.

Ixodes ricinus is a vector of several pathogens of public health interest. While forests are the primary habitat for I. ricinus, its abundance and infection prevalence are expected to vary within forest stands. This study assesses the spatio-temporal variations in tick abundance and infection prevalence with three pathogens in and around a peri-urban forest where human exposure is high. Ticks were sampled multiple times in 2016 and 2018 in multiple locations with a diversity of undergrowth, using the consecutive drags method. Three zoonotic pathogens were screened for, Borrelia burgdorferi s.l., Coxiella burnetii, and Francisella tularensis. The influence of season, type of site and micro-environmental factors on tick abundance were assessed with negative binomial generalized linear mixed-effects models. We collected 1642 nymphs and 181 adult ticks. Ticks were most abundant in the spring, in warmer temperatures, and where undergrowth was higher. Sites with vegetation unaffected by human presence had higher abundance of ticks. Forest undergrowth type and height were significant predictors of the level of tick abundance in a forest. The consecutive drags method is expected to provide more precise estimates of tick abundance, presumably through more varied contacts with foliage. Borrelia burgdorferi s.l. prevalence was estimated from pooled ticks at 5.33%, C. burnetii was detected in six pools and F. tularensis was not detected. Borrelia afzelii was the dominant B. burgdorferi genospecies. Tick abundance and B. burgdorferi s.l. infection prevalence were lower than other estimates in Belgian forests.

The multifunction Coxiella effector Vice stimulates macropinocytosis and interferes with the ESCRT machinery.

Intracellular bacterial pathogens divert multiple cellular pathways to establish their niche and persist inside their host. Coxiella burnetii, the causative agent of Q fever, secretes bacterial effector proteins via its Type 4 secretion system to generate a Coxiella-containing vacuole (CCV). Manipulation of lipid and protein trafficking by these effectors is essential for bacterial replication and virulence. Here, we have characterized the lipid composition of CCVs and found that the effector Vice interacts with phosphoinositides and membranes enriched in phosphatidylserine and lysobisphosphatidic acid. Remarkably, eukaryotic cells ectopically expressing Vice present compartments that resemble early CCVs in both morphology and composition. We found that the biogenesis of these compartments relies on the double function of Vice. The effector protein initially localizes at the plasma membrane of eukaryotic cells where it triggers the internalization of large vacuoles by macropinocytosis. Then, Vice stabilizes these compartments by perturbing the ESCRT machinery. Collectively, our results reveal that Vice is an essential C. burnetii effector protein capable of hijacking two major cellular pathways to shape the bacterial replicative niche.

Delayed diagnosis of persistent Q fever: a case series from China.

BACKGROUND: Q fever, caused by the zoonotic pathogen Coxiella burnetii, exhibits a worldwide prevalence. In China, Q fever is not recognized as a notifiable disease, and the disease is overlooked and underestimated in clinical practice, leading to diagnostic challenges. CASE PRESENTATION: We present a case series of three patients diagnosed with persistent Q fever between 2022 and 2023. The average age of our three cases was 63.33 years old, consisting of two males and one female. The medical history of the individuals included previous valve replacement, aneurysm followed by aortic stent-graft placement and prosthetic hip joint replacement. At the onset of the disease, only one case exhibited acute fever, while the remaining two cases were devoid of any acute symptoms. The etiology was initially overlooked until metagenomic next-generation sequencing test identified Coxiella burnetii from the blood or biopsy samples. Delayed diagnosis was noted, with a duration ranging from three months to one year between the onset of the disease and its confirmation. The epidemiological history uncovered that none of the three cases had direct exposure to domestic animals or consumption of unpasteurized dairy products. Case 1 and 2 resided in urban areas, while Case 3 was a rural resident engaged in farming. All patients received combination therapy of doxycycline and hydroxychloroquine, and no recurrence of the disease was observed during the follow-up period. CONCLUSION: Q fever is rarely diagnosed and reported in clinical practice in our country. We should be aware of persistent Q fever in high-risk population, even with unremarkable exposure history. Metagenomic next-generation sequencing holds great potential as a diagnostic tool for identifying rare and fastidious pathogens such as Coxiella burnetii.

Molecular identification of Coxiella burnetii in raw milk samples collected from farm animals in districts Kasur and Lahore of Punjab, Pakistan.

Coxiella burnetii is the worldwide zoonotic infectious agent for Q fever in humans and animals. Farm animals are the main reservoirs of C. burnetii infection, which is mainly transmitted via tick bites. In humans, oral, percutaneous, and respiratory routes are the primary sources of infection transmission. The clinical signs vary from flu-like symptoms to endocarditis for humans' acute and chronic Q fever. While it is usually asymptomatic in livestock, abortion, stillbirth, infertility, mastitis, and endometritis are its clinical consequences. Infected farm animals shed C. burnetii in birth products, milk, feces, vaginal mucus, and urine. Milk is an important source of infection among foods of animal origin. This study aimed to determine the prevalence and molecular characterization of C. burnetii in milk samples of dairy animals from two districts in Punjab, Pakistan, as it has not been reported there so far. Using a convenience sampling approach, the current study included 304 individual milk samples from different herds of cattle, buffalo, goats, and sheep present on 39 farms in 11 villages in the districts of Kasur and Lahore. PCR targeting the IS1111 gene sequence was used for its detection. Coxiella burnetii DNA was present in 19 of the 304 (6.3%) samples. The distribution was 7.2% and 5.2% in districts Kasur and Lahore, respectively. The results showed the distribution in ruminants as 3.4% in buffalo, 5.6% in cattle, 6.7% in goats, and 10.6% in sheep. From the univariable analysis, the clinical signs of infection i.e. mastitis and abortion were analyzed for the prevalence of Coxiella burnetii. The obtained sequences were identical to the previously reported sequence of a local strain in district Lahore, Sahiwal and Attock. These findings demonstrated that the prevalence of C. burnetii in raw milk samples deserves more attention from the health care system and veterinary organizations in Kasur and Lahore of Punjab, Pakistan. Future studies should include different districts and human populations, especially professionals working with animals, to estimate the prevalence of C. burnetii.

Efficacy of rifapentine and other rifamycins against Coxiella burnetii in vitro.

Since 1999, doxycycline and hydroxychloroquine have been the recommended treatment for chronic Q fever, a life-threatening disease caused by the bacterial pathogen, Coxiella burnetii. Despite the duration of its use, the treatment is not ideal due to the lengthy treatment time, high mortality rate, resistant strains, and the potential for contraindicated usage. A literature search was conducted to identify studies that screened large panels of drugs against C. burnetii to identify novel targets with potential efficacy against C. burnetii. Twelve candidate antimicrobials approved for use in humans by the US Food and Drug Administration were selected and minimum inhibitory concentrations (MICs) were determined against the low virulence strain Nine Mile phase II. Rifabutin and rifaximin were the best performing antibiotics tested with MICs of ≤0.01 µg mL-1. Further screening of these top candidates was conducted alongside two drugs from the same class, rifampin, well-characterized, and rifapentine, not previously reported against C. burnetii. These were screened against virulent strains of C. burnetii representing three clinically relevant genotypes. Rifapentine was the most effective in the human monocytic leukemia cell line, THP-1, with a MIC ≤0.01 µg mL-1. In the human kidney epithelial cell line, A-498, efficacy of rifapentine, rifampin, and rifabutin varied across C. burnetii strains with MICs between ≤0.001 and 0.01 µg mL-1. Rifampin, rifabutin, and rifapentine were all bactericidal against C. burnetii; however, rifabutin and rifapentine demonstrated impressive bactericidal activity as low as 0.1 µg mL-1 and should be further explored as alternative Q fever treatments given their efficacy in vitro. IMPORTANCE: This work will help inform investigators and physicians about potential alternative antimicrobial therapies targeting the causative agent of Q fever, Coxiella burnetii. Chronic Q fever is difficult to treat, and alternative antimicrobials are needed. This manuscript explores the efficacy of rifamycin antibiotics against virulent strains of C. burnetii representing three clinically relevant genotypes in vitro. Importantly, this study determines the susceptibility of C. burnetii to rifapentine, which has not been previously reported. Evaluation of the bactericidal activity of the rifamycins reveals that rifabutin and rifapentine are bactericidal at low concentrations, which is unusual for antibiotics against C. burnetii.

Coxiella burnetii-containing vacuoles interact with host recycling endosomal proteins Rab11a and Rab35 for vacuolar expansion and bacterial growth.

Introduction: Coxiella burnetii is a gram-negative obligate intracellular bacterium and a zoonotic pathogen that causes human Q fever. The lack of effective antibiotics and a licensed vaccine for Coxiella in the U.S. warrants further research into Coxiella pathogenesis. Within the host cells, Coxiella replicates in an acidic phagolysosome-like vacuole termed Coxiella-containing vacuole (CCV). Previously, we have shown that the CCV pH is critical for Coxiella survival and that the Coxiella Type 4B secretion system regulates CCV pH by inhibiting the host endosomal maturation pathway. However, the trafficking pattern of the 'immature' endosomes in Coxiella- infected cells remained unclear. Methods: We transfected HeLa cells with GFP-tagged Rab proteins and subsequently infected them with mCherry-Coxiella to visualize Rab protein localization. Infected cells were immunostained with anti-Rab antibodies to confirm the Rab localization to the CCV, to quantitate Rab11a and Rab35- positive CCVs, and to quantitate total recycling endosome content of infected cells. A dual-hit siRNA mediated knockdown combined with either immunofluorescent assay or an agarose-based colony-forming unit assay were used to measure the effects of Rab11a and Rab35 knockdown on CCV area and Coxiella intracellular growth. Results: The CCV localization screen with host Rab proteins revealed that recycling endosome-associated proteins Rab11a and Rab35 localize to the CCV during infection, suggesting that CCV interacts with host recycling endosomes during maturation. Interestingly, only a subset of CCVs were Rab11a or Rab35-positive at any given time point. Quantitation of Rab11a/Rab35-positive CCVs revealed that while Rab11a interacts with the CCV more at 3 dpi, Rab35 is significantly more prevalent at CCVs at 6 dpi, suggesting that the CCV preferentially interacts with Rab11a and Rab35 depending on the stage of infection. Furthermore, we observed a significant increase in Rab11a and Rab35 fluorescent intensity in Coxiella-infected cells compared to mock, suggesting that Coxiella increases the recycling endosome content in infected cells. Finally, siRNA-mediated knockdown of Rab11a and Rab35 resulted in significantly smaller CCVs and reduced Coxiella intracellular growth, suggesting that recycling endosomal Rab proteins are essential for CCV expansion and bacterial multiplication. Discussion: Our data, for the first time, show that the CCV dynamically interacts with host recycling endosomes for Coxiella intracellular survival and potentially uncovers novel host cell factors essential for Coxiella pathogenesis.

Coxiella burnetii effector CvpE maintains biogenesis of Coxiella-containing vacuoles by suppressing lysosome tubulation through binding PI(3)P and perturbing PIKfyve activity on lysosomes.

Coxiella burnetii (C. burnetii) is the causative agent of Q fever, a zoonotic disease. Intracellular replication of C. burnetii requires the maturation of a phagolysosome-like compartment known as the replication permissive Coxiella-containing vacuole (CCV). Effector proteins secreted by the Dot/Icm secretion system are indispensable for maturation of a single large CCV by facilitating the fusion of promiscuous vesicles. However, the mechanisms of CCV maintenance and evasion of host cell clearance remain to be defined. Here, we show that C. burnetii secreted Coxiella vacuolar protein E (CvpE) contributes to CCV biogenesis by inducing lysosome-like vacuole (LLV) enlargement. LLV fission by tubulation and autolysosome degradation is impaired in CvpE-expressing cells. Subsequently, we found that CvpE suppresses lysosomal Ca2+ channel transient receptor potential channel mucolipin 1 (TRPML1) activity in an indirect manner, in which CvpE binds phosphatidylinositol 3-phosphate [PI(3)P] and perturbs PIKfyve activity in lysosomes. Finally, the agonist of TRPML1, ML-SA5, inhibits CCV biogenesis and C. burnetii replication. These results provide insight into the mechanisms of CCV maintenance by CvpE and suggest that the agonist of TRPML1 can be a novel potential treatment that does not rely on antibiotics for Q fever by enhancing Coxiella-containing vacuoles (CCVs) fission.

Occurrence of Coxiella burnetii in wild lagomorphs and their ticks in Spanish Mediterranean ecosystems.

BACKGROUND: Coxiella burnetii, the causative agent of Q fever, is a zoonotic multi-host vector-borne pathogen of major public health importance. Although the European Food Safety Authority has recently made the monitoring of this bacterium in wildlife a priority, the role of wild lagomorphs in the transmission and maintenance of C. burnetii is poorly understood. AIMS: The aims of this study were to determine the prevalence and risk factors associated with C. burnetii circulation in European wild rabbits (Oryctolagus cuniculus) and Iberian hares (Lepus granatensis) and to assess the presence of this pathogen in ticks that feed on them in Mediterranean ecosystems in Spain, the country with the highest number of reported cases of Q fever in Europe. METHODS: A total of 574 spleen samples were collected from 453 wild rabbits and 121 Iberian hares, and 513 ticks (processed in 120 pools) between the 2017/2018 and 2021/2022 hunting seasons. RESULTS: C. burnetii DNA was detected in 103 (17.9%; 95% CI: 14.8-21.1) of the 574 wild lagomorphs tested. By species, prevalence was 16.3% (74/453; 95% CI: 12.9-19.7) in the European wild rabbit and 24.0% (29/121; 95% CI: 16.4-31.6) in the Iberian hare. At least one positive lagomorph was found on 47.9% of the 96 hunting estates sampled and in every hunting season since 2018/2019. Two risk factors associated with C. burnetii infection were as follows: outbreak of myxomatosis on the hunting estate in the month prior to sampling and high tick abundance observed by gamekeepers on the hunting estate. C. burnetii DNA was also found in 33 of the 120 (27.5%; 95% CI: 19.5-35.5) tick pools tested. The pathogen was detected in 66.7% (4/6), 29.2% (26/89) and 21.4% (3/14) of Haemaphysalis hispanica, Rhipicephalus pusillus and Hyalomma lusitanicum pools respectively. CONCLUSIONS: This study provides new epidemiological data on C. burnetii in European wild rabbits and is the first survey on this zoonotic pathogen performed in Iberian hares. Our results indicate widespread endemic circulation of C. burnetii and highlight the importance of both wild lagomorph species as natural reservoirs of this zoonotic bacterium in Mediterranean ecosystems in southern Spain, which may be of public and animal health concern. The high prevalence and wide diversity of positive tick species suggest the possible role of ticks in the epidemiological cycle of C. burnetii, with the potential risk of transmission to sympatric species, including humans.

One Health approach to Coxiella burnetii in Brazilian indigenous communities.

Indigenous health has posted complex challenges worldwide, particularly due to historical economic, territorial, social and environmental processes, which may lead to emergence and reemergence of pathogens. In addition to few Coxiella burnetii serosurveys in vulnerable populations, especially in developing tropical countries, no comprehensive One Health approach has focused on human-animal infection along with potential environmental determinants. Accordingly, this study aimed to assess the seroprevalence of anti-C. burnetii antibodies in indigenous populations and their dogs from 10 indigenous communities distributed in southern and southeastern Brazil, along with the correspondent healthcare professionals. In overall, 8/893 (0.90%; 95% CI 0.45-1.76) indigenous and 1/406 (0.25%) dog samples were seropositive, with 7/343 (2.04%) individuals the 1/144 (0.69%) dog from the Ocoy community, located in the city of São Miguel do Iguaçu, bordering Argentina at south, and far 10 km at west from Paraguay. All 84 healthcare professionals tested seronegative.

Tissue distribution of Coxiella burnetii and antibody responses in macropods co-grazing with livestock in Queensland, Australia.

Coxiella burnetii, the causative agent of Q fever, is a zoonotic bacteria of global public health significance. The organism has a complex, diverse, and relatively poorly understood animal reservoir but there is increasing evidence that macropods play some part in the epidemiology of Q fever in Australia. The aim of this cross-sectional survey was to estimate the animal- and tissue-level prevalence of coxiellosis amongst eastern grey (Macropus giganteus) and red (Osphranter rufus) kangaroos co-grazing with domestic cattle in a Q fever endemic area in Queensland. Serum, faeces and tissue samples from a range of organs were collected from 50 kangaroos. A total of 537 tissue samples were tested by real-time PCR, of which 99 specimens from 42 kangaroos (84% of animals, 95% confidence interval [CI], 71% to 93%) were positive for the C. burnetii IS1111 gene when tested in duplicate. Twenty of these specimens from 16 kangaroos (32%, 95% CI 20% to 47%) were also positive for the com1 or htpAB genes. Serum antibodies were present in 24 (57%, 95% CI 41% to 72%) of the PCR positive animals. There was no statistically significant difference in PCR positivity between organs and no single sample type consistently identified C. burnetii positive kangaroos. The results from this study identify a high apparent prevalence of C. burnetii amongst macropods in the study area, albeit seemingly with an inconsistent distribution within tissues and in relatively small quantities, often verging on the limits of detection. We recommend Q fever surveillance in macropods should involve a combination of serosurveys and molecular testing to increase chances of detection in a population, noting that a range of tissues would likely need to be sampled to confirm the diagnosis in a suspect positive animal.

Pigs in southern Italy are exposed to three ruminant pathogens: an analysis of seroprevalence and risk factors analysis study.

BACKGROUND: Pigs are susceptible to several ruminant pathogens, including Coxiella burnetti, Schmallenberg virus (SBV) and bovine viral diarrhea virus (BVDV). These pathogens have already been described in the pig population, although the dynamics of the infection and the impact on pig farms are currently unclear. The aim of this work was to evaluate the presence of these infections in the pig population of the Campania region, southern Italy, and to evaluate the risk factors associated with a greater risk of exposure. RESULTS: A total of 414 serum samples belonging to 32 herds were tested for the presence of antibodies against SBV, Coxiella, and BVD using commercial multispecies ELISA kits. SBV (5.3%) was the most prevalent pathogen, followed by Coxiella (4.1%) and BVD (3%). The risk factors included in the study (age, sex, province, farming system, ruminant density and major ruminant species) had no influence on the probability of being exposed to BVD and Coxiella, except for the location, in fact more pigs seropositive to Coxiella were found in the province of Caserta. However, the univariate analysis highlighted the influence of age, location, and sex on exposure to SBV. The subsequent multivariate analysis statistically confirmed the importance of these factors. The presence of neutralizing antibodies for SBV and BVDV, or antibodies directed towards a specific phase of infection for Coxiella was further confirmed with virus-neutralization assays and phase-specific ELISAs in a large proportion of positive samples. The presence of high neutralizing antibody titers (especially for SBV) could indicate recent exposures. Twelve of the 17 positive samples tested positive for antibodies against Coxiella phase I or II antigens, indicating the presence of both acute and chronic infections (one animal tested positive for both phases antibodies). CONCLUSIONS: Our study indicates a non-negligible exposure of pigs from southern Italy to the above pathogens. Further studies are necessary to fully understand the dynamics of these infections in pigs, the impact on productivity, and the public health consequences in the case of Coxiella.

Bacterial burden and molecular characterization of Coxiella burnetii in shedding pregnant and postpartum ewes from Saint Kitts.

This study aimed to evaluate the bacterial burden and perform molecular characterization of Coxiella burnetii during shedding in pregnant (vaginal, mucus and feces) and postpartum (vaginal mucus, feces and milk) ewes from Saint Kitts. Positive IS1111 DNA (n=250) for C. burnetii samples from pregnant (n=87) and postpartum (n=74) Barbados Blackbelly ewes in a previous investigation were used for this study. Vaginal mucus (n=118), feces (n=100), and milk (n=32) positive IS1111 C. burnetii-DNA were analysed by real time qPCR (icd gene). For molecular characterization of C. burnetii, selected (n=10) IS1111 qPCR positive samples were sequenced for fragments of the IS1111 element and the 16 S rRNA gene. nBLAST, phylogenetic and haplotype analyses were performed. Vaginal mucus, feces and milk had estimated equal amounts of bacterial DNA (icd copies), and super spreaders were detected within the fecal samples. C. burnetii haplotypes had moderate to high diversity, were ubiquitous worldwide and similar to previously described in ruminants and ticks and humans.

Distribution and pathogen prevalence of field-collected ticks from south-western Korea: a study from 2019 to 2022.

Hard ticks are known vectors of various pathogens, including the severe fever with thrombocytopenia syndrome virus, Rickettsia spp., Coxiella burnetii, Borrelia spp., Anaplasma phagocytophilum, and Ehrlichia spp. This study aims to investigate the distribution and prevalence of tick-borne pathogens in southwestern Korea from 2019 to 2022. A total of 13,280 ticks were collected during the study period, with H. longicornis accounting for 86.1% of the collected ticks. H. flava, I. nipponensis and A. testudinarium comprised 9.4%, 3.6%, and 0.8% of the ticks, respectively. Among 983 pools tested, Rickettsia spp. (216 pools, 1.6% MIR) were the most prevalent pathogens across all tick species, with R. japonica and R. monacensis frequently detected in I. nipponensis and Haemaphysalis spp., respectively. Borrelia spp. (28 pools, 0.2% MIR) were predominantly detected in I. nipponensis (27 pools, 13.8% MIR, P < 0.001). Co-infections, mainly involving Rickettsia monacensis and Borrelia afzelii, were detected in I. nipponensis. Notably, this study identified R. monacensis for the first time in A. testudinarium in South Korea. These findings offer valuable insights into the tick population and associated pathogens in the region, underscoring the importance of tick-borne disease surveillance and prevention measures.

Occurrence of Coxiellosis in ruminants and its associated risk factors.

Coxiellosis in animals is caused by the zoonotic pathogen, Coxiella burnetii. Although the disease is of public health importance it remains underdiagnosed and underreported. The cross- sectional study was aimed to estimate the occurrence of the disease in livestock of study area and also to identify the risk factors associated with the disease in animals. Blood, serum, and vaginal swabs samples were collected from 200 ruminants (cattle, sheep, and goats), across various farms in Karnataka, India. These samples were then screened using ELISA and PCR (com1 and IS1111). A questionnaire was administered to the farm owners to collect the risk factor-related information. About 5.26 % cattle, 12.3 % sheep, and 12.5 % goats were positive by ELISA. By PCR, 9.47 % cattle, 9.3 % sheep, and 10 % goats were positive. Overall, the occurrence of 14.73 %, 18.46 % and 17.5 % was estimated in cattle, sheep and goat, respectively. PCR targeting the IS1111 gene detected higher number of samples as positive as compared to the com1 gene PCR. Higher number of vaginal swab samples were detected as positive as compared to blood. History of reproductive disorders (OR: 4.30; 95 %CI:1.95- 9.46), abortion (OR: 30.94; 95 %CI:6.30- 151.84) and repeat breeding (OR:11.36; 95 %CI:4.16- 30.99) were significantly associated with coxiellosis (p < 0.005). Multivariable analysis by logistic regression model analysis suggested retained abortion, repeat breeding and rearing of animal in semi-intensive system as factors significantly associated with the infection. Cultural identification of the PCR positive samples were cultured using embryonated egg propagation and cell culture techniques and positivity was confirmed in six samples. Phylogenetic analysis of the com1 and IS1111 gene revealed clustering based on similar geographic locations. The study estimated the occurrence of the disease in the study area and identified the potential risk factors.

Exposure of small ruminants and humans to Coxiella burnetii in the semi-arid region of Northeastern Brazil.

Q fever is a zoonotic disease caused by the obligate intracellular pathogen Coxiella burnetii, for which domestic ruminants are the primary source of infection in humans. Herein, we investigated the presence of C. burnetii in humans, sheep, and goats in the semi-arid region of northeastern Brazil. The presence of anti-C. burnetii antibodies was surveyed using indirect immunofluorescence assay, and detection of C. burnetii DNA was performed by polymerase chain reaction (PCR). Anti-C. burnetii antibodies were detected in 60% of farms, 4.8% of goats, 1.5% of sheep, and 4.5% of human samples. PCR was positive in 18.9% of blood samples, 7.7% of milk samples, and 7.7% of vaginal mucus samples. A DNA sequence of a C. burnetii DNA sample extracted from the goat vaginal mucus showed 99.2-99.4% nucleotide identity with other strains previously reported in Brazil. These results indicate that C. burnetii is present in the surveyed area, where it poses a risk to both public and animal health. These findings indicate an urgent need for educative actions to protect population, as well as better training of veterinarians to detect and report Q fever.

Coxiella burnetii serostatus in dromedary camels (Camelus dromedarius) is associated with the presence of C. burnetii DNA in attached ticks in Laikipia County, Kenya.

AIMS: Q fever is a globally distributed, neglected zoonotic disease of conservation and public health importance, caused by the bacterium Coxiella burnetii. Coxiella burnetii normally causes subclinical infections in livestock, but may also cause reproductive pathology and spontaneous abortions in artiodactyl species. One such artiodactyl, the dromedary camel (Camelus dromedarius), is an increasingly important livestock species in semi-arid landscapes. Ticks are naturally infected with C. burnetii worldwide and are frequently found on camels in Kenya. In this study, we assessed the relationship between dromedary camels' C. burnetii serostatus and whether the camels were carrying C. burnetii PCR-positive ticks in Kenya. We hypothesized that there would be a positive association between camel seropositivity and carrying C. burnetii PCR-positive ticks. METHODS AND RESULTS: Blood was collected from camels (N = 233) from three herds, and serum was analysed using commercial ELISA antibody test kits. Ticks were collected (N = 4354), divided into pools of the same species from the same camel (N = 397) and tested for C. burnetii and Coxiella-like endosymbionts. Descriptive statistics were used to summarize seroprevalence by camel demographic and clinical variables. Univariate logistic regression analyses were used to assess relationships between serostatus (outcome) and tick PCR status, camel demographic variables, and camel clinical variables (predictors). Camel C. burnetii seroprevalence was 52%. Across tick pools, the prevalence of C. burnetii was 15% and Coxiella-like endosymbionts was 27%. Camel seropositivity was significantly associated with the presence of a C. burnetii PCR-positive tick pool (OR: 2.58; 95% CI: 1.4-5.1; p = 0.0045), increasing age class, and increasing total solids. CONCLUSIONS: The role of ticks and camels in the epidemiology of Q fever warrants further research to better understand this zoonotic disease that has potential to cause illness and reproductive losses in humans, livestock, and wildlife.

Ultraviolet C inactivation of Coxiella burnetii for production of a structurally preserved whole cell vaccine antigen.

Q fever, a worldwide-occurring zoonotic disease, can cause economic losses for public and veterinary health systems. Vaccines are not yet available worldwide and currently under development. In this regard, it is important to produce a whole cell antigen, with preserved structural and antigenic properties and free of chemical modifications. Thus, inactivation of Coxiella burnetii with ultraviolet light C (UVC) was evaluated. C. burnetii Nine Mile phase I (NMI) and phase II (NMII) were exposed to decreasing intensities in a time-dependent manner and viability was tested by rescue cultivation in axenic medium or cell culture. Effects on the cell structure were visualized by transmission electron microscopy and antigenicity of UVC-treated NMI was studied by immunization of rabbits. NMI and NMII were inactivated at UVC intensities of 250 µW/cm2 for 5 min or 100 µW/cm2 for 20 min. Reactivation by DNA repair was considered to be unlikely. No morphological changes were observed directly after UVC inactivation by transmission electron microscopy, but severe swelling and membrane degradation of bacteria with increasing severity occurred after 24 and 48 h. Immunization of rabbits resulted in a pronounced antibody response. UVC inactivation of C. burnetii resulted in a structural preserved, safe whole cell antigen and might be useful as antigen for diagnostic purposes or as vaccine candidate.

A case report of Vancomycin in the treatment of Q fever endocarditis.

The patient, a 43-year-old male, was admitted to the hospital with gradually aggravated exertional palpitations and chest tightness over a 2-day period. Upon hospital admission, a cardiac ultrasound revealed aortic valve redundancy, however multiple blood culture investigations came back negative. Blood mNGS was perfected, revealing Coxiella burnetii, and the diagnosis of Q fever (query fever) was established. The temperature and inflammatory indices of the patient were all normal with the treatment of vancomycin before cardiac surgery. But for the potential liver damage of and the Coxiella burnetii was still positive in the anti-phase II IgG titer, the doxycycline and hydroxychloroquine instead of vancomycin were applied for the patient. Despite receiving standardized anti-infective therapy of doxycycline combined with hydroxychloroquine, this patient had fever and increased leukocytes following surgery. After the addition of vancomycin as an anti-infective treatment, the temperature and leukocytes improved quickly. During the treatment of vancomycin, a discovery of liver injury may have resulted. These findings provide new therapy options for future professionals.