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Tick-borne pathogens are significant for human, veterinary, and wildlife health. Coxiella burnetii is an example that is widely distributed across various hosts and can cross species boundaries. In Pakistan, there is a scarcity of data regarding C. burnetii at the intersection of wildlife and livestock. Ticks were collected from ruminants and wildlife from the districts of Kasur, Pakpattan, and Okara in Pakistan. Five tick species totaling 571 ticks were collected, with the following distribution: 56.4% Hyalomma anatolicum, 22.4% Rhipicephalus microplus, 10.5% Hyalomma marginatum, 7.9% Rhipicephalus sanguineus, and 2.8% Rhipicephalus turanicus. Fifty tick pools were screened for C. burnetii to amplify a segment of the IS1111 using real-time PCR assays. Ticks collected from sheep and goats had a greater rate of positivity for C. burnetii (40% and 38%, respectively) compared to Indian long-eared hedgehogs with a prevalence of 2%. Coxiella burnetii was prominent in Rhipicephalus microplus (92.3%) and Hyalomma anatolicum (88.9%), followed by Rhipicephalus turanicus (66.6%), Rhipicephalus sanguineus (33.3%), and Hyalomma marginatum (25.0%). Ticks from Pakpattan district displayed the highest prevalence of C. burnetii (88.9%), whereas the lowest was observed in ticks from Kasur district (77.3%). There was no significant association between tick gender and C. burnetii infection. Female host animals were more likely to harbor ticks containing C. burnetii, with a prevalence rate of 81.8%. The research underscores the urgent need for comprehensive studies on C. burnetii in Pakistan, especially at the interface of wildlife and livestock. The high prevalence rates observed in certain tick species and geographic regions emphasize the importance of targeted public health interventions. Future research should focus on elucidating the transmission dynamics and implementing effective control measures to mitigate the impact of these pathogens on human, veterinary, and wildlife health in the region.

Asunto(s)

Animales Salvajes , Coxiella burnetii , Cabras , Ixodidae , Fiebre Q , Infestaciones por Garrapatas , Animales , Coxiella burnetii/aislamiento & purificación , Coxiella burnetii/genética , Pakistán/epidemiología , Infestaciones por Garrapatas/veterinaria , Infestaciones por Garrapatas/epidemiología , Femenino , Fiebre Q/veterinaria , Fiebre Q/epidemiología , Fiebre Q/microbiología , Ixodidae/microbiología , Masculino , Ovinos , Prevalencia , Erizos/microbiología , Erizos/parasitología , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Enfermedades de las Ovejas/epidemiología , Enfermedades de las Ovejas/microbiología , Enfermedades de las Cabras/epidemiología , Enfermedades de las Cabras/microbiología , Animales Domésticos

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This study aimed to assess epidemiological trends of Q fever in six countries of Southeast Europe by analysing surveillance data for 2002-2021 period. In this descriptive analysis, we collected and analysed data on confirmed human Q fever cases, obtained from the national Public Health Institutes of Bosnia and Herzegovina, Croatia, Greece, Montenegro, North Macedonia and Serbia. Overall, 2714 Q fever cases were registered during the 20-year period. The crude average annual notification rate was 0.82 (± 2.06) (95% CI: 0.47-1.16) per 100,000 inhabitants, ranged from 0.06 (± 0.04) (95% CI: 0.04-0.08) /100,000 in Greece to 2.78 (± 4.80) (95% CI: 0.53-5.02) /100,000 in the Republic of Srpska (entity of Bosnia and Herzegovina). Significant declining trends of Q fever age standardized rates were registered in Croatia, the Federation of Bosnia and Herzegovina, North Macedonia and Serbia, with an average annual change of -30.15%; -17.13%; -28.33% and - 24.77%, respectively. An unequal spatial distribution was observed. The highest average age-specific notification rate was reported in the 20-59 age group (0.84 (± 0.40) (95% CI: 0.65-1.02) /100,000). Most cases (53.69%) were reported during the spring. Q fever remains a significant public health threat in this part of Europe. The findings of this study revealed the endemic maintenance of this disease in the including countries, with large regional and subnational disparities in notification rates. A downward trend was found in Q fever notification rates across the study countries with the average notification rate higher than in the EU/EEA, during the same period.

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Objective: This study aimed to investigate the seroprevalence of Q fever and its association with age and gender among Saanen dairy goats in Malaysia. Materials and Methods: One hundred dairy goats (n = 100) aged 6 months to 6 years were randomly selected, and blood samples were collected for serological analysis using the enzyme-linked immunosorbent assay technique. Results: The results revealed a seropositive rate of 70% among the goats, with medium-positive titers being the most common. The prevalence of Q fever varied among different age groups, with higher rates observed in adult goats aged between 5 and 6 years. Gender analysis showed that males had a higher positive rate (p < 0.05) of Q fever compared to females. Conclusion: These findings strongly indicate the presence of Coxiella burnetii in the dairy goat population and highlight the importance of implementing biosecurity measures and control strategies to prevent further transmission of this disease. This research has contributed to a better understanding of Q fever epidemiology and provides insights for effective control and prevention strategies in dairy goat populations.

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Various zoonotic microorganisms cause reproductive problems such as abortions and stillbirths, leading to economic losses on farms, particularly within livestock. In South Africa, bovine brucellosis is endemic in cattle, and from 2013-2018, outbreaks of Brucella melitensis occurred in sable. Coxiella burnetii, the agent responsible for the zoonotic disease known as Q-fever and/or coxiellosis, also causes reproductive problems and infects multiple domestic animal species worldwide, including humans. However, little is known of this disease in wildlife. With the expansion of the wildlife industry in South Africa, diseases like brucellosis and coxiellosis can significantly impact herd breeding success because of challenges in identifying, managing and treating diseases in wildlife populations. This study investigated samples obtained from aborted sable and roan antelope, initially suspected to be brucellosis, from game farms in South Africa using serology tests and ruminant VetMAX™ polymerase chain reaction (PCR) abortion kit. The presence of C. burnetii was confirmed with PCR in a sable abortion case, while samples from both sable and roan were seropositive for C. burnetii indirect enzyme-linked immunosorbent assay (iELISA). This study represents the initial report of C. burnetii infection in sable and roan antelope in South Africa. Epidemiological investigations are crucial to assess the risk of C. burnetii in sable and roan populations, as well as wildlife and livestock in general, across South Africa. This is important in intensive farming practices, particularly as Q-fever, being a zoonotic disease, poses a particular threat to the health of veterinarians and farm workers as well as domestic animals.Contribution: A report of clinical C. burnetii infection in the wildlife industry contributes towards the limited knowledge of this zoonotic disease in South Africa.

Asunto(s)

Antílopes , Coxiella burnetii , Fiebre Q , Animales , Sudáfrica/epidemiología , Fiebre Q/veterinaria , Fiebre Q/epidemiología , Coxiella burnetii/aislamiento & purificación , Femenino , Aborto Veterinario/microbiología , Aborto Veterinario/epidemiología , Animales Salvajes/microbiología

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Feral swine are invasive in the United States and a reservoir for infectious diseases. The increase in feral swine population and the geographic range are a concern for the spread of zoonotic diseases to humans and livestock. Feral swine could contribute to the spread of Coxiella burnetii, the causative agent of human Q fever. In this study, we characterized the seroprevalence of C. burnetii in feral swine populations of Hawai'i and Texas, which have low and high rates of human Q fever, respectively. Seropositivity rates were as high as 0.19% and 6.03% in Hawai'i and Texas, respectively, indicating that feral swine cannot be ruled out as a potential reservoir for disease transmission and spread. In Texas, we identified the overlap between seropositivity of feral swine and human Q fever incidence. These results indicate that there is a potentially low but detectable risk of C. burnetii exposure associated with feral swine populations in Hawai'i and Texas.

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The case presents a 47-year-old man with sudden abdominal pain and fever, but the cause was uncertain. Through metagenomic next-generation sequencing (mNGS) and detecting Q fever antibodies in serum, along with the patient's clinical and epidemiological history, a precise diagnosis was made, enabling timely and proper treatment.

Asunto(s)

Coxiella burnetii , Secuenciación de Nucleótidos de Alto Rendimiento , Metagenómica , Fiebre Q , Humanos , Coxiella burnetii/genética , Coxiella burnetii/aislamiento & purificación , Masculino , Fiebre Q/diagnóstico , Fiebre Q/microbiología , Persona de Mediana Edad , Metagenómica/métodos , Genoma Bacteriano/genética , Anticuerpos Antibacterianos/sangre

RESUMEN

This study investigated the prevalence, antimicrobial resistance, and genetic diversity of Staphylococcus aureus, as well as the detection and genetic relationship of Coxiella burnetii in retail milk samples and plastic bags from 25 local dairy delicatessens. Bacteriological culture, PCR, and Sanger sequencing were performed. Eleven percent of the samples were positive for S. aureus, none of which were methicillin-resistant or enterotoxigenic. The rep-PCR analysis revealed a high similarity between strains isolated from milk and bag samples from the same source. Moreover, 14% of the milk samples were positive for C. burnetii, which matched 100% of the reference strains in the GenBank.

RESUMEN

Introduction: Understanding multi-pathogen infections/exposures in livestock is critical to inform prevention and control measures against infectious diseases. We investigated the co-exposure of foot-and-mouth disease virus (FMDV), Brucella spp., Leptospira spp., and Coxiella burnetii in cattle in three zones stratified by land use change and with different wildlife-livestock interactions in Narok county, Kenya. We also assessed potential risk factors associated with the transmission of these pathogens in cattle. Methods: We identified five villages purposively, two each for areas with intensive (zone 1) and moderate wildlife-livestock interactions (zone 2) and one for locations with low wildlife-livestock interactions (zone 3). We sampled 1,170 cattle from 390 herds through a cross-sectional study and tested the serum samples for antibodies against the focal pathogens using enzyme-linked immunosorbent assay (ELISA) kits. A questionnaire was administered to gather epidemiological data on the putative risk factors associated with cattle's exposure to the investigated pathogens. Data were analyzed using the Bayesian hierarchical models with herd number as a random effect to adjust for the within-herd clustering of the various co-exposures among cattle. Results: Overall, 88.0% (95% CI: 85.0-90.5) of the cattle tested positive for at least one of the targeted pathogens, while 41.7% (95% CI: 37.7-45.8) were seropositive to at least two pathogens. FMDV and Brucella spp. had the highest co-exposure at 33.7% (95% CI: 30.9-36.5), followed by FMDV and Leptospira spp. (21.8%, 95% CI: 19.5-24.4), Leptospira spp. and Brucella spp. (8.8%, 95% CI: 7.2-10.6), FMDV and C. burnetii (1.5%, 95% CI: 0.7-2.8), Brucella spp. and C. burnetii (1.0%, 95% CI: 0.3-2.2), and lowest for Leptospira spp. and C. burnetii (0.3%, 95% CI: 0.0-1.2). Cattle with FMDV and Brucella spp., and Brucella spp. and Leptospira spp. co-exposures and those simultaneously exposed to FMDV, Brucella spp. and Leptospira spp. were significantly higher in zone 1 than in zones 2 and 3. However, FMDV and Leptospira spp. co-exposure was higher in zones 1 and 2 than zone 3. Discussion/conclusion: We recommend the establishment of a One Health surveillance system in the study area to reduce the morbidity of the targeted zoonotic pathogens in cattle and the risks of transmission to humans.

RESUMEN

BACKGROUND: Coxiella burnetii is a bacterium with extreme tenacity and contagiousness that is mainly transmitted by inhalation of contaminated aerosols. Nevertheless, a transmission by ticks is under discussion. We report a case of Q fever in an urban environment and far away from sheep breeding that caused a rare right-sided endocarditis. CASE PRESENTATION: A 55-year-old man who was in good health before the event developed a C. burnetii -endocarditis of the tricuspid valve. He had no contact with sheep and no recent travel in a rural or even endemic area. The infection originated in a strictly urban environment, and the patient's occupation as a cemetery gardener in Berlin, coupled with the close temporal and local exposure to wild boar, made a transmission by these animals a plausible hypothesis. The infection was confirmed by the German Reference Laboratory, and the patient recovered completely after treatment with doxycycline and hydrochlorquine. CONCLUSIONS: The specialities of this case report are the right-sided endocarditis and the transmission of C. burnetii in a metropolitan area without sheep contact. We think that this case should serve to increase awareness of the potential for Q fever infection even in non-rural areas.

Asunto(s)

Coxiella burnetii , Endocarditis Bacteriana , Fiebre Q , Válvula Tricúspide , Fiebre Q/transmisión , Fiebre Q/microbiología , Fiebre Q/diagnóstico , Fiebre Q/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Humanos , Válvula Tricúspide/microbiología , Endocarditis Bacteriana/microbiología , Endocarditis Bacteriana/transmisión , Endocarditis Bacteriana/tratamiento farmacológico , Coxiella burnetii/aislamiento & purificación , Animales , Antibacterianos/uso terapéutico , Doxiciclina/uso terapéutico , Ovinos

RESUMEN

Coxiella burnetii is a globally distributed obligate intracellular pathogen. Although often asymptomatic, infections can cause acute Q fever with influenza-like symptoms and/or severe chronic Q fever. Coxiella burnetii develops a unique replicative niche within host cells called the Coxiella-containing vacuole (CCV), facilitated by the Dot/Icm type IV secretion system translocating a cohort of bacterial effector proteins into the host. The role of some effectors has been elucidated; however, the actions of the majority remain enigmatic and the list of true effectors is disputable. This study examined CBU2016, a unique C. burnetii protein previously designated as an effector with a role in infection. We were unable to validate CBU2016 as a translocated effector protein. Employing targeted knock-out and complemented strains, we found that the loss of CBU2016 did not cause a replication defect within Hela, THP-1, J774, or iBMDM cells or in axenic media, nor did it affect the pathogenicity of C. burnetii in the Galleria mellonella infection model. The absence of CBU2016 did, however, result in a consistent decrease in the size of CCVs in HeLa cells. These results suggest that although CBU2016 may not be a Dot/Icm effector, it is still able to influence the host environment during infection.

Asunto(s)

Proteínas Bacterianas , Coxiella burnetii , Fiebre Q , Vacuolas , Coxiella burnetii/genética , Coxiella burnetii/metabolismo , Coxiella burnetii/patogenicidad , Humanos , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Vacuolas/microbiología , Vacuolas/metabolismo , Animales , Fiebre Q/microbiología , Células HeLa , Línea Celular , Factores de Virulencia/metabolismo , Factores de Virulencia/genética , Técnicas de Inactivación de Genes , Mariposas Nocturnas/microbiología , Interacciones Huésped-Patógeno , Células THP-1

RESUMEN

Although we live in the genomic era, the accessibility of the complete genome sequence of Coxiella burnetii, the etiological agent of Q fever, has increased knowledge in the field of genomic diversity of this agent However, it is still somewhat of a "question" microorganism. The epidemiology of Q fever is intricate due to its global distribution, repository and vector variety, as well as absence of surveys defining the dynamic interaction among these factors. Moreover, C. burnetii is a microbial agent that can be utilized as a bioterror weapon. Therefore, typing techniques used to recognize the strains can also be used to trace infections back to their source which is of great significance. In this paper, the latest and current typing techniques of C. burnetii spp. are reviewed illustrating their advantages and constraints. Recently developed multi locus VNTR analysis (MLVA) and single-nucleotide polymorphism (SNP) typing methods are promising in improving diagnostic capacity and enhancing the application of genotyping techniques for molecular epidemiologic surveys of the challenging pathogen. However, most of these studies did not differentiate between C. burnetii and Coxiella-like endosymbionts making it difficult to estimate the potential role that ticks play in the epidemiology of Q fever. Therefore, it is necessary to analyze the vector competence of different tick species to transmit C. burnetii. Knowledge of the vector and reservoir competence of ticks is important for taking adequate preventive measures to limit infection risks. The significant prevalence observed for the IS1111 gene underscores its substantial presence, while other genes display comparatively lower prevalence rates. Methodological variations, particularly between commercial and non-commercial kit-based methods, result in different prevalence outcomes. Variations in sample processing procedures also lead to significant differences in prevalence rates between mechanical and non-mechanical techniques.

Asunto(s)

Coxiella burnetii , Fiebre Q , Coxiella burnetii/genética , Coxiella burnetii/clasificación , Coxiella burnetii/aislamiento & purificación , Fiebre Q/microbiología , Fiebre Q/epidemiología , Fiebre Q/diagnóstico , Humanos , Técnicas de Genotipaje/métodos , Animales , Genotipo , Polimorfismo de Nucleótido Simple , Repeticiones de Minisatélite

RESUMEN

Introduction: Tick-borne pathogens, such as Borreliella spp., Rickettsia spp., and Anaplasma spp., are frequently detected in Germany. They circulate between animals and tick vectors and can cause mild to severe diseases in humans. Knowledge about distribution and prevalence of these pathogens over time is important for risk assessment of human and animal health. Methods: Ixodes ricinus nymphs were collected at different locations in 2009/2010 and 2019 in Germany and analyzed for tick-borne pathogens by real-time PCR and sequencing. Results: Borreliella spp. were detected with a prevalence of 11.96% in 2009/2010 and 13.10% in 2019 with B. afzelii and B. garinii as dominant species. Borrelia miyamotoi was detected in seven ticks and in coinfection with B. afzelii or B. garinii. Rickettsia spp. showed a prevalence of 8.82% in 2009/2010 and 1.68% in 2019 with the exclusive detection of R. helvetica. The prevalence of Anaplasma spp. was 1.00% in 2009/2010 and 7.01% in 2019. A. phagocytophilum was detected in seven tick samples. None of the nymphs were positive for C. burnetii. Discussion: Here, observed changes in prevalence were not significant after a decade but require longitudinal observations including parameters like host species and density, climatic factors to improve our understanding of tick-borne diseases.

Asunto(s)

Ixodes , Enfermedades por Picaduras de Garrapatas , Animales , Alemania/epidemiología , Ixodes/microbiología , Prevalencia , Enfermedades por Picaduras de Garrapatas/epidemiología , Enfermedades por Picaduras de Garrapatas/microbiología , Ninfa/microbiología , Borrelia/aislamiento & purificación , Borrelia/genética , Humanos , Rickettsia/genética , Rickettsia/aislamiento & purificación , Anaplasma/genética , Anaplasma/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa

RESUMEN

Coxiella burnetii is the causative agent of Q fever. The main reservoirs for this bacterium, which can lead to human infection, in our region are typically cattle, goats, and sheep. In animals, C. burnetii infection is often detected due to reproductive problems. European Member States are required to report confirmed cases annually, but the lack of uniform reporting methods makes the data rather inconsistent. The Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise is involved in official controls to identify the causes of abortions, monitor suspected or positive herds, evaluate suspected infections in pets and humans, monitor the spread in wildlife, etc. In this paper, we summarize the presence of C. burnetii over the last five years (2019-2023). Additionally, a detailed overview of C. burnetii infection in wild and domestic animals is provided. Five hundred sixty animals-including cattle; goats; sheep; wild animals, such as deer, boars, wolves, roe deer, owls, and otters; buffalo; dogs; horses; cats; and a donkey-and six human samples were tested by real-time PCR on the transposase gene IS1111 to detect C. burnetii. The MST profile was identified in some of the samples. Outbreaks of C. burnetii occurred in four herds. In one of them, it was possible to follow the outbreak from inception to eradication by evaluating the effect of vaccination on real-time PCR Ct values. A total of 116 animals tested positive for C. burnetii, including 73 goats, 42 sheep, and one bovine. None of the other samples tested positive. The strains for which the ST was performed were identified as ST79, a strain that has been present in the area for more than ten years. The effect of vaccination on the reduction of positive samples and the variation of real-time PCR Ct values was evaluated in strict correlation.

RESUMEN

The objective of this study was to apply and preliminarily evaluate a High-Resolution Melting (HRM) analysis technique coupled with qPCR, that allows the simultaneous detection of 10 different ruminant abortogenic pathogens, for investigating abortions in sheep and goats throughout Greece. A total of 264 ovine and caprine vaginal swabs were obtained the week following the abortion from aborted females and analyzed using a commercially available kit (ID Gene™ Ruminant Abortion Multiplex HRM, Innovative Diagnostics). Results indicated a high prevalence of Coxiella burnetii and Chlamydophila spp., which were detected in 48.9% and 42.4% of the vaginal swabs, respectively. Results for these most commonly detected pathogens were compared with those of a well-established commercial qPCR kit, with near-perfect agreement. Toxoplasma gondii, Salmonella spp., Brucella spp., Anaplasma phagocytophilum, Campylobacter fetus, and Neospora caninum were also identified, the two latter reported for the first time in the country in small ruminants. Mixed infections occurred in 35.6% of the animals examined. This technique allows for the simultaneous detection of many abortogenic pathogens in an accurate and cost-effective assay. Detection of uncommon or not previously reported pathogens in various cases indicates that their role in ovine and caprine abortions may be underestimated.

RESUMEN

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.

Asunto(s)

Coxiella burnetii , Lynx , Fiebre Q , Animales , Lynx/microbiología , Coxiella burnetii/aislamiento & purificación , Fiebre Q/veterinaria , Fiebre Q/epidemiología , Fiebre Q/microbiología , España/epidemiología , Femenino , Masculino , Estudios Seroepidemiológicos , Prevalencia , Estudios Longitudinales

RESUMEN

Introduction: Coxiella burnetii (C. burnetii)-infected livestock and wildlife have been epidemiologically linked to human Q fever outbreaks. Despite this growing zoonotic threat, knowledge of coxiellosis in wild animals remains limited, and studies to understand their epidemiologic role are needed. In C. burnetii-endemic areas, ticks have been reported to harbor and spread C. burnetii and may serve as indicators of risk of infection in wild animal habitats. Therefore, the aim of this study was to compare molecular techniques for detecting C. burnetii DNA in ticks. Methods: In total, 169 ticks from wild animals and cattle in wildlife conservancies in northern Kenya were screened for C. burnetii DNA using a conventional PCR (cPCR) and two field-friendly techniques: Biomeme's C. burnetii qPCR Go-strips (Biomeme) and a new C. burnetii PCR high-resolution melt (PCR-HRM) analysis assay. Results were evaluated, in the absence of a gold standard test, using Bayesian latent class analysis (BLCA) to characterize the proportion of C. burnetii positive ticks and estimate sensitivity (Se) and specificity (Sp) of the three tests. Results: The final BLCA model included main effects and estimated that PCR-HRM had the highest Se (86%; 95% credible interval: 56-99%), followed by the Biomeme (Se = 57%; 95% credible interval: 34-90%), with the estimated Se of the cPCR being the lowest (24%, 95% credible interval: 10-47%). Specificity estimates for all three assays ranged from 94 to 98%. Based on the model, an estimated 16% of ticks had C. burnetii DNA present. Discussion: These results reflect the endemicity of C. burnetii in northern Kenya and show the promise of the PCR-HRM assay for C. burnetii surveillance in ticks. Further studies using ticks and wild animal samples will enhance understanding of the epidemiological role of ticks in Q fever.

RESUMEN

Coxiella burnetii is a highly infectious, Gram-negative, obligate intracellular bacterium and the causative agent of human Q fever. The Coxiella Containing Vacuole (CCV) is a modified phagolysosome that forms through fusion with host endosomes and lysosomes. While an initial acidic pH < 4.7 is essential to activate Coxiella metabolism, the mature, growth-permissive CCV has a luminal pH of ~5.2 that remains stable throughout infection. Inducing CCV acidification to a lysosomal pH (~4.7) causes Coxiella degradation, suggesting that Coxiella regulates CCV pH. Supporting this hypothesis, Coxiella blocks host lysosomal biogenesis, leading to fewer host lysosomes available to fuse with the CCV. Host cell lysosome biogenesis is primarily controlled by the transcription factor EB (TFEB), which binds Coordinated Lysosomal Expression And Regulation (CLEAR) motifs upstream of genes involved in lysosomal biogenesis and function. TFEB is a member of the microphthalmia/transcription factor E (MiT/TFE) protein family, which also includes MITF, TFE3, and TFEC. This study examines the roles of MiT/TFE proteins during Coxiella infection. We found that in cells lacking TFEB, both Coxiella growth and CCV size increase. Conversely, TFEB overexpression or expression in the absence of other family members leads to significantly less bacterial growth and smaller CCVs. TFE3 and MITF do not appear to play a significant role during Coxiella infection. Surprisingly, we found that Coxiella actively blocks TFEB nuclear translocation in a Type IV Secretion System-dependent manner, thus decreasing lysosomal biogenesis. Together, these results suggest that Coxiella inhibits TFEB nuclear translocation to limit lysosomal biogenesis, thus avoiding further CCV acidification through CCV-lysosomal fusion. IMPORTANCE: The obligate intracellular bacterial pathogen Coxiella burnetii causes the zoonotic disease Q fever, which is characterized by a debilitating flu-like illness in acute cases and life-threatening endocarditis in patients with chronic disease. While Coxiella survives in a unique lysosome-like vacuole called the Coxiella Containing Vacuole (CCV), the bacterium inhibits lysosome biogenesis as a mechanism to avoid increased CCV acidification. Our results establish that transcription factor EB (TFEB), a member of the microphthalmia/transcription factor E (MiT/TFE) family of transcription factors that regulate lysosomal gene expression, restricts Coxiella infection. Surprisingly, Coxiella blocks TFEB translocation from the cytoplasm to the nucleus, thus downregulating the expression of lysosomal genes. These findings reveal a novel bacterial mechanism to regulate lysosomal biogenesis.

Asunto(s)

Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice , Coxiella burnetii , Lisosomas , Fiebre Q , Coxiella burnetii/genética , Coxiella burnetii/metabolismo , Coxiella burnetii/fisiología , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Lisosomas/metabolismo , Humanos , Fiebre Q/microbiología , Animales , Vacuolas/metabolismo , Vacuolas/microbiología , Ratones , Núcleo Celular/metabolismo , Transporte de Proteínas

RESUMEN

Coxiella burnetii, the causative agent of Q fever, is an intracellular pathogen posing a significant global public health threat. There is a pressing need for dependable and effective treatments, alongside an urgency for further research into the molecular characterization of its genome. Within the genomic landscape of Coxiella burnetii, numerous hypothetical proteins remain unidentified, underscoring the necessity for in-depth study. In this study, we conducted comprehensive in silico analyses to identify and prioritize potential hypothetical protein of Coxiella burnetii, aiming to elucidate the structure and function of uncharacterized protein. Furthermore, we delved into the physicochemical properties, localization, and molecular dynamics and simulations, and assessed the primary, secondary, and tertiary structures employing a variety of bioinformatics tools. The in-silico analysis revealed that the uncharacterized protein contains a conserved Mth938-like domain, suggesting a role in preadipocyte differentiation and adipogenesis. Subcellular localization predictions indicated its presence in the cytoplasm, implicating a significant role in cellular processes. Virtual screening identified ligands with high binding affinities, suggesting the protein's potential as a drug target against Q fever. Molecular dynamics simulations confirmed the stability of these complexes, indicating their therapeutic relevance. The findings provide a structural and functional overview of an uncharacterized protein from C. burnetii, implicating it in adipogenesis. This study underscores the power of in-silico approaches in uncovering the biological roles of uncharacterized proteins and facilitating the discovery of new therapeutic strategies. The findings provide valuable preliminary data for further investigation into the protein's role in adipogenesis.

Asunto(s)

Adipogénesis , Proteínas Bacterianas , Coxiella burnetii , Simulación de Dinámica Molecular , Coxiella burnetii/metabolismo , Coxiella burnetii/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/química , Fiebre Q/microbiología , Humanos

RESUMEN

Birds are known to be carriers of ticks infected by tick-borne pathogens, including bacteria. However, not many studies have been carried out on avian tissues to detect these agents. The aim of the present survey was to investigate, using PCR, the presence of Anaplasma phagocytophilum, Bartonella spp., Borrelia burgdorferi sensu lato, Chlamydia psittaci, Coxiella burnetii, Ehrlichia canis, Francisella tularensis, and Rickettsia spp. in the spleens collected from 300 wild birds of different orders and species from Central Italy. A total of 53 (17.67%) samples were PCR positive for at least one investigated pathogen. One (0.33%) bird was positive for Bartonella spp., five (1.67%) birds were positive for C. burnetii, eleven (3.67%) for B. burgdorferi s.l., and thirty-six (12%) for C. psittaci. No coinfection was detected. All samples were negative for A. phagocytophilum, E. canis, F. tularensis, and Rickettsia spp. The findings showed that wild birds may harbor different zoonotic tick-borne bacteria; therefore, they can contribute to the diffusion of these agents.

RESUMEN

Q fever is a worldwide distribution disease caused by Coxiella burnetii（C. burnetii）, an obligate intracellular, Gram-negative acidophilic bacterium belonging to γ-proteobacterium. Most patients present with acute Q-fever accompanied by atypical flu-like symptoms, with only 1%-5% of cases may develop into persistent and focally infected foci, mainly manifest as endocarditis, osteomyelitis and prosthetic arthritis. In this case, the patient experienced an unexplained and uninterrupted fever up to 39.2 °C for a week, accompanied by chills and headaches, as well as abnormal liver function. The laboratory reported negative results for blood culture and respiratory-associated pathogens, however, the metagenomic next-generation sequencing (mNGS) reported that detection of 20 sequence reads of C. burnetii in the patient's peripheral blood. In addition, the patient had traveled to Sri Lanka, Iraq and Saudi Arabia before illness. In clinical, the treatment regimen was adjusted from empirically intravenous moxifloxacin 400 mg a day for 1 week to continuously oral minocyline 100 mg twice daily for 2 weeks. The patient was in good health without any adverse sequelae during outpatient visitation and the phone calls follow-up. In conclusion, the mNGS does provide an early and timely diagnostic basis for rare and difficult to culture pathogens, which contributes to the success of clinical anti-infection.