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1.
Front Cell Infect Microbiol ; 14: 1323054, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38567022

RESUMO

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.


Assuntos
Coxiella burnetii , Endocardite Bacteriana , Febre Q , Masculino , Humanos , Adulto , Febre Q/diagnóstico , Febre Q/tratamento farmacológico , Vancomicina/uso terapêutico , Doxiciclina/uso terapêutico , Hidroxicloroquina , Endocardite Bacteriana/diagnóstico , Endocardite Bacteriana/tratamento farmacológico
2.
BMC Microbiol ; 24(1): 118, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575865

RESUMO

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.


Assuntos
Coxiella burnetii , Febre Q , Vacinas , Animais , Coelhos , Febre Q/microbiologia
3.
J Clin Microbiol ; 62(4): e0170323, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38470022

RESUMO

Serum polymerase chain reaction (PCR) for the detection of Coxiella burnetii DNA has been suggested for rapid Q fever diagnosis. We evaluated the role of PCR testing in serum in the diagnosis of acute Q fever in an endemic setting. We examined patients suspected of acute Q fever tested for C. burnetii-specific serum real-time PCR in a tertiary hospital between January 2019 toand December 2022. In the first half, PCR orders were consultation-based by infectious diseases specialists, while in the second half, they were guided by serology, positive IgM2, and negative IgG1 and IgG2, indicating early acute infection. Logistic regression analyzed independent predictors for positive PCR. PCR positivity rates were calculated using various clinical criteria in the diagnostic algorithm. Out of 272 patients, 13 (4.8%) tested positive and 130 exhibited serologically suspected early infection. Presentation during April-July and aspartate aminotransferase (AST) > 3× upper normal limit (UNL) were independently associated with positive PCR with an odds ratio (OR) = 15.03 [95% confidence interval (CI), 1.58-142.46], P = 0.018 and OR = 55.44 [95% CI, 6.16-498.69], P < 0.001, respectively. PCR positivity rate was 8.5% in serologically suspected early infection vs 1.4% in other serology, yielding OR = 6.4 [95% CI, 1.4-29.7], P = 0.009. Adding AST > 3× UNL increased OR to 49.5 [95% CI, 5.9-408.7], P ≤ 0.001 reducing required PCR tests for a single acute Q fever case from 11.8 to 3. Elevated AST in serologically suspected early Q fever is proposed to be used in a diagnostic stewardship algorithm integrating PCR in serum in an endemic setting. IMPORTANCE: Our study suggests in a diagnostic stewardship approach the integration of molecular testing (Coxiella burnetii targeted PCR) for the diagnosis of acute Q fever in a reliable time in the endemic setting. Integrating PCR detecting Coxiella burnetii in serum in routine testing of suspected early acute Q fever based on serology result increased the PCR positivity rate significantly. Adding increased transaminases optimizes PCR utility which is highly requested particularly in endemic areas.


Assuntos
Coxiella burnetii , Febre Q , Humanos , Coxiella burnetii/genética , Febre Q/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real , DNA Bacteriano , Imunoglobulina G , Algoritmos
4.
Prev Vet Med ; 225: 106157, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38452603

RESUMO

Coxiella burnetii is a Gram-negative bacterium that causes the zoonotic disease Q fever. Wild boars serve as reservoirs for C. burnetii. This study aimed to identify the risk factors associated with C. burnetii infection in wild boars. We analyzed the data from 975 wild boar samples collected from June to November 2021 in South Korea. We utilized the indirect ELISA to detect antibodies against C. burnetii. A sample optical density to positive-control optical density value exceeding 50% was classified as positive. We gathered data on the forestation, terrain, weather, agriculture, and animal density of the region where the samples were collected. Continuous variables were categorized into tertiles. We performed a univariate logistic regression analysis and included variables with a p-value < 0.2 in the final multivariable logistic regression model. In our multivariable logistic regression analysis to identify risk factors for C. burnetii infection in wild boars, we used a forward selection method to enter variables based on the order of their significance. We performed the final multivariable logistic regression analyses using either continuous variables or variables categorized into tertiles. The prevalence of C. burnetii was 14.6% (n=142). Locations with the highest maximum wind speeds (3.92-8.24 m/s) showed a 59% increase in infection odds compared to locations with the lowest speeds (1.45-3.25 m/s)(p=0.044). For each 1 m/s increase in maximum wind speed, infection odds increased by 24.1% (p=0.037). Regions with the highest percentage of paddy fields per area (8.3-45%) showed a 76% increase in infection odds compared to regions with the lowest percentage (0-1.5%)(p=0.011). For each 1% increase in the proportion of paddy fields per area, infection odds increased by 3.3% (p=0.003). High maximum wind speed and a high percentage of paddy field were identified as significant risk factors for C. burnetii infection in wild boars.


Assuntos
Coxiella burnetii , Febre Q , Animais , Estudos Soroepidemiológicos , Febre Q/epidemiologia , Febre Q/veterinária , Febre Q/microbiologia , Fatores de Risco , República da Coreia/epidemiologia , Prevalência
5.
Acta Microbiol Immunol Hung ; 71(1): 76-81, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38466372

RESUMO

We report a case of exposure to Coxiella burnetii in a surgical nurse who underwent an injury of her finger with a scalpel blade during a native aortic valve replacement with a bio-prosthetic cardiac valve conducted on a patient suffering from C. burnetii aortic endocarditis. Given the positivity of C. burnetii culture and PCR from the patient's aortic valve, she was prescribed prophylactic doxycycline 100 mg twice a day for 10 days. Q fever is an occupational zoonosis resulting usually of exposure to infected animals by inhalation of infected aerosols or consumption of contaminated raw milk. Apart from materno-foetal transmission, about 180 cases of human-to-human C. burnetii transmission have been published from 1949 to today, including transmission by blood transfusion, sexual relations, transmission in the healthcare setting to staff, patient attendants and other patients that were likely infected from inhalation of aerosol from respiratory or placental products, transmission to staff during autopsies of patients with Q fever and transmission in familial settings. As C. burnetii is a highly infectious bacterium, that may cause infection with a low inoculum, it should be added to the list of organisms which may be of concern following blood exposure among healthcare professionals.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Coxiella burnetii , Exposição Ocupacional , Febre Q , Humanos , Animais , Feminino , Gravidez , Coxiella burnetii/genética , Febre Q/microbiologia , Placenta
6.
Trop Anim Health Prod ; 56(3): 106, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38507146

RESUMO

Coxiella burnetii, or Q fever agent, has notable implications for human and livestock health. Infections in cattle primarily manifest through reproductive issues where infected animals shed the bacterium in birth fluids, placental tissues, and milk, serving as potential sources of transmission. Bovine herds become reservoirs, contributing to the environmental contamination of farming areas. Comprehensive studies on the prevalence, transmission routes, and associated risk factors among cattle contribute to the development of effective control strategies, ultimately safeguarding both livestock and public health.Here we determine the prevalence of Coxiella burnetii antibodies against in dairy cattle farms from Kabylia (northern Algeria) and identify the associated risk factors. Bulk tank milk samples from 184 farms were analyzed by indirect ELISA technique, 49 of them were tested positive which corresponds to a prevalence rate of 26.63% (95% CI 20.25-33.01%). Multivariate analysis by logistic regression showed that the risk factors associated with detection of anti-Coxiella burnetii antibodies are: cohabitation of cattle with small ruminants(OR = 3.74 95% CI [1.41-8.92]), exposure to prevailing winds (OR = 5.12 95% CI [2.11-13.45]), and the veterinarian visits frequency(OR = 5.67 95% CI [2.55-13.60]). These findings underscore the susceptibility of dairy cattle to Q fever in the Kabylia region, highlighting practices that pose risks. We recommend the implementation of hygienic measures and adherence to proper farming conditions to mitigate the transmission of Q fever and reduce the associated zoonotic risk.


Assuntos
Doenças dos Bovinos , Coxiella burnetii , Febre Q , Humanos , Bovinos , Animais , Feminino , Gravidez , Febre Q/epidemiologia , Febre Q/veterinária , Febre Q/microbiologia , Leite/microbiologia , Prevalência , Argélia/epidemiologia , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Placenta , Anticorpos Antibacterianos , Fatores de Risco , Anticorpos Antiprotozoários
7.
Appl Environ Microbiol ; 90(3): e0220123, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38412030

RESUMO

Coxiella burnetii infection was monitored during seven kidding seasons (2017-2023) in a dairy goat herd that after an outbreak of Q fever abortions was vaccinated with an inactivated phase I vaccine. Due to the high infection rate just after the outbreak, only the replacement stock was vaccinated during the first three kidding seasons, and when the average herd immunity had decreased (fourth kidding season onwards), the whole herd was vaccinated. Vaginal swabs, feces, and milk were analyzed by PCR to monitor infection, and dust and aerosols were analyzed to measure C. burnetii environmental contamination. One year after the onset of the outbreak, a significant reduction in C. burnetii shedding loads was observed, but the percentage of shedding animals remained high until the third kidding season. By the seventh kidding season, no shedders were detected. The bacterial load excreted was significantly lower in vaccinated compared with unvaccinated animals, and in yearlings compared with multiparous. C. burnetii was detected by PCR in aerosols collected inside the animal premises throughout the study period except in the last season; whereas, aerosols collected outdoors tested negative in the last three kidding seasons. Viable C. burnetii was detectable in environmental dust collected inside the barn until the third kidding season following the outbreak. These results indicate that after an outbreak of Q fever, the risk of infection for humans and susceptible animals can remain high for at least three kidding seasons when the number of C. burnetii animal shedders is still high, even when bacterial excretion is low. IMPORTANCE: Q fever is a zoonosis distributed worldwide. Ruminants are the main reservoir, and infection can cause high rates of abortion. After entering a farm, Coxiella burnetii infection can persist in the animal population over several lambing/kidding periods. Once infection is established in a herd, vaccination with the inactivated Phase I vaccine significantly reduces bacterial shedding, but although at low levels, excretion may continue to occur for several lambing/kidding seasons. The time that C. burnetii remains viable in the farm environment after an outbreak of Q fever determines the period when risk of infection is high for the people in close contact. This work showed that this period extends at least three kidding seasons after the outbreak. These results provided valuable information on the epidemiology of C. burnetii infection in goat herds and may help to develop guidelines for controlling the disease and reducing infection risk for susceptible people and animals.


Assuntos
Coxiella burnetii , Doenças das Cabras , Febre Q , Vacinas , Gravidez , Feminino , Humanos , Animais , Ovinos , Febre Q/epidemiologia , Febre Q/prevenção & controle , Febre Q/veterinária , Estações do Ano , Cabras , Surtos de Doenças/veterinária , Vacinação/veterinária , Aerossóis , Poeira , Doenças das Cabras/epidemiologia , Doenças das Cabras/prevenção & controle , Doenças das Cabras/microbiologia
8.
BMC Infect Dis ; 24(1): 172, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326756

RESUMO

BACKGROUND: Spontaneous miscarriage, a leading health concern globally, often occurs due to various factors, including infections. Among these, Coxiella burnetii and Brucella spp. may have adverse effects on pregnancy outcomes. While previous research has established a link between infections and spontaneous miscarriage, our study aimed specifically to investigate the presence of these two pathogens in abortion samples from women who experienced spontaneous miscarriages in Iran. Our study can add to the existing knowledge by focusing on Iran, a region with a high prevalence of C. burnetii and Brucella spp. As a result, it could provide a better understanding and unique insights into the relationship of these pathogens with spontaneous miscarriages in endemic regions. METHODS: From March 2021 to March 2022, a total of 728 abortion samples (including placenta and cotyledon) were collected from 409 women who had experienced spontaneous miscarriages in the provinces of Tehran, Fars, and West Azerbaijan in Iran. The specimens included 467 Formalin-Fixed Paraffin-Embedded (FFPE) and 261 fresh frozen samples. After DNA extraction from abortion samples, the quantitative real-time PCR (qPCR) assay targeted a specific fragment of the IS1111 and IS711 elements for molecular identification of C. burnetii and Brucella spp., respectively. Furthermore, the qPCR assay employing specific primers for different species was used to determine the species of Brucella. RESULTS: Among the studied women, 1 out of 409 (0.24%) samples tested positive for Brucella spp., specifically Brucella melitensis. There were no positive specimens for C. burnetii. CONCLUSIONS: Our study contributes to understanding the potential involvement of Brucella species in spontaneous infectious abortion within endemic regions. The identification of B. melitensis in this study highlights the need for further research in this area. However, while our results suggest a relatively low or zero identification of these pathogens in our sample population, this does not rule out the possibility of undetected infections. Therefore, it is critical to acknowledge the limitations of the molecular techniques used (qPCR), which may have potential limitations such as sensitivity and specificity. Moreover, because 64.15% of our samples were FFPE, the sensitivity of the qPCR test may be reduced. These raise concerns about the accuracy of the reported prevalence rates and the potential for false positives or negatives.


Assuntos
Aborto Espontâneo , Brucella melitensis , Brucelose , Coxiella burnetii , Febre Q , Humanos , Gravidez , Feminino , Coxiella burnetii/genética , Aborto Espontâneo/epidemiologia , Irã (Geográfico)/epidemiologia , Brucelose/epidemiologia , Brucella melitensis/genética , Febre Q/epidemiologia
9.
Infect Genet Evol ; 118: 105562, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38307395

RESUMO

The present study was conducted with the aim of investigating the prevalence and genetic structure of Coxiella burnetii in tick samples collected from domestic animals in Hormozgan province146 tick samples were randomly collected from cattle, sheep, goat, camel and dog herds in seven cities of Hormozgan. After the DNA was extracted from each tick sample; Nested-PCR method was used to identify the presence of C. burnetii using IS1111 transposon gene and isocitrate dehydrogenase icd gene. In addition, phylogenetic analysis and tree diagram were constructed based on IS1111 and icd genes. The results showed that out of 146 pool tick samples, 40 pool samples based on IS1111 gene and 32 pool samples based on icd gene were infected with C. burnetii. When results were stratified by livestock type, infection rates were highest in sheep ticks (37.5%, 95% CI: 21.2% - 57.29%), followed by cattle ticks (32.14%, 95% CI: 17.90% - 50.66%) and dog tick (15%, 95% CI: 70.6% - 29%). In camel and goat ticks, the infection rate was 15.90 and 23.07%, respectively. In conclusion, this study emphasizes the role of ticks as potential carriers of C. burneti. The results indicate the importance of cattle, sheep, goats, camels and dogs in Hormozgan region as effective factors in the epidemiology of Q fever and its impact on public health. In addition, a high degree of similarity (from 99% to 100%) was observed between IS1111 and icd genes in this study and recorded sequences from different regions of the world.


Assuntos
Coxiella burnetii , Carrapatos , Animais , Cães , Camelus , Coxiella burnetii/genética , Cabras , Irã (Geográfico)/epidemiologia , Filogenia , Rhipicephalus sanguineus , Carrapatos/microbiologia
10.
Vaccine ; 42(8): 1993-2003, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38388237

RESUMO

Q fever in humans is caused by Coxiella (C.) burnetii. In 2008 and 2012, cases of Q fever in humans were linked to an infected flock of approximately 650 ewes. Since 2013 gimmers (G'13, G'14, G'15 etc.) were primary vaccinated (two doses) with an inactivated C.burnetii vaccine without any revaccination. In 2013, 30 ewes were primary vaccinated (A'13). Shedding was annually monitored by qPCR-testing of vaginal and nasal swabs collected at lambing. Animals were tested for Phase I- (PhI) and PhII-antibodies (Ab) and for PhII-specific-interferon-γ (IFN-γ) before and after vaccination. The effect of a revaccination was determined in 2018 and 2023. Groups of randomly selected gimmers primary vaccinated in 2015, 2016 and 2017 and a mixed group of older animals (A'13, G'13 and G'14) were revaccinated once in 2018. The trial was repeated in 2023 on groups primary vaccinated in 2019-2023. Major shedding after the outbreak in 2012 ceased in 2014. Thereafter C.burnetii was only sporadically detected at low-level in 2018, 2021 and 2023. Sheep naturally exposed to C.burnetii during the outbreak in 2012 (A'13, G'13) mounted a strong and complete (PhI, PhII, IFN-γ) recall immune response after vaccination. A serological PhI+/PhII+ pattern dominated after vaccination. In contrast, since 2014 a weaker immune response (PhII-titre, IFN-γ) and a dominance of the PhI-/PhII+ pattern was observed in vaccinated gimmers. The number of serologically non-responding gimmers to vaccination increased to 25.0 % in G'16/G'17 and 40.4 % in G'19/G'20. But revaccination even three (G'15 in 2018) and four (G'19 in 2023) years after primary vaccination resulted in a strong and complete immune response. No difference of the immune response nor to more recently primary vaccinated animals (G'23 in 2023) nor to those animals that were present during the outbreak (A'13/G'13/G'14 in 2018) was observed.


Assuntos
Coxiella burnetii , Febre Q , Humanos , Ovinos , Animais , Feminino , Febre Q/prevenção & controle , Febre Q/veterinária , Febre Q/epidemiologia , Anticorpos , Vacinas Bacterianas , Imunidade
11.
Infect Immun ; 92(3): e0056022, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38363133

RESUMO

The Gram-negative bacterium Coxiella burnetii is the causative agent of query fever in humans and coxiellosis in livestock. C. burnetii infects a variety of cell types, tissues, and animal species including mammals and arthropods, but there is much left to be understood about the molecular mechanisms at play during infection in distinct species. Human stimulator of interferon genes (STING) induces an innate immune response through the induction of type I interferons (IFNs), and IFN promotes or suppresses C. burnetii replication, depending on tissue type. Drosophila melanogaster contains a functional STING ortholog (Sting) which activates NF-κB signaling and autophagy. Here, we sought to address the role of D. melanogaster Sting during C. burnetii infection to uncover how Sting regulates C. burnetii infection in flies. We show that Sting-null flies exhibit higher mortality and reduced induction of antimicrobial peptides following C. burnetii infection compared to control flies. Additionally, Sting-null flies induce lower levels of oxidative stress genes during infection, but the provision of N-acetyl-cysteine (NAC) in food rescues Sting-null host survival. Lastly, we find that reactive oxygen species levels during C. burnetii infection are higher in Drosophila S2 cells knocked down for Sting compared to control cells. Our results show that at the host level, NAC provides protection against C. burnetii infection in the absence of Sting, thus establishing a role for Sting in protection against oxidative stress during C. burnetii infection.


Assuntos
Coxiella burnetii , Febre Q , Animais , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , NF-kappa B/metabolismo , Febre Q/microbiologia , Espécies Reativas de Oxigênio/metabolismo
12.
Comp Immunol Microbiol Infect Dis ; 106: 102126, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38325127

RESUMO

Aiming at identifying the reservoir and contamination sources of Coxiella burnetii in Northern Algeria, we investigated the molecular presence of the bacterium in 599 samples (blood, placenta, liver, spleen, and uterus) collected from cattle, sheep, dogs and cats. Our qPCR results showed that 15/344 (4.36%) blood samples and six/255 (2.35%) organ specimens were positive for C. burnetii. In cattle, three (4%) blood and liver samples were positive. In sheep, one blood (1.19%) and 3 (8.57%) placenta samples were positive. At the Algiers dog pound, 8 (10%) and 3 (5%) blood samples were qPCR positivein dogs and cats, respectively. In addition, MST genotyping showed that MST 33 was present in cattle and sheep, MST 20 in cattle,andMST 21 in dogs and cats.


Assuntos
Doenças do Gato , Doenças dos Bovinos , Coxiella burnetii , Doenças do Cão , Doenças das Cabras , Febre Q , Doenças dos Ovinos , Gravidez , Feminino , Animais , Cães , Gatos , Bovinos , Ovinos , Coxiella burnetii/genética , Febre Q/epidemiologia , Febre Q/veterinária , Febre Q/microbiologia , Genótipo , Argélia/epidemiologia , Doenças do Gato/microbiologia , Doenças do Cão/epidemiologia , Doenças do Cão/microbiologia , Doenças dos Bovinos/microbiologia , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/microbiologia , Ruminantes , Cabras , Doenças das Cabras/microbiologia
13.
Port J Card Thorac Vasc Surg ; 30(4): 59-62, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38345879

RESUMO

Q fever is an ubiquitous zoonosis caused by Coxiella burnetii, an intracellular bacterium that can produce acute or chronic infections in humans. These forms are characterized by different evolution, serological profile and treatment that must be very long to achieve a cure in chronic forms. However, the serological profile for diagnosis and the real value of serology for predicting outcome are controversial, and management dilemmas for many patients with Q fever infection are continuously emerging. In this case report, we present a 20-year-old man from Nicaragua who worked as a farmer with a culture-negative infective endocarditis who presented with a mycotic aneurysm. The present report reviews the clinical presentation and diagnosis of Q fever IE.


Assuntos
Aneurisma Infectado , Coxiella burnetii , Endocardite , Aneurisma Intracraniano , Febre Q , Masculino , Humanos , Adulto Jovem , Adulto , Febre Q/complicações , Aneurisma Infectado/diagnóstico , Aneurisma Intracraniano/complicações
14.
Adv Healthc Mater ; 13(7): e2302351, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38198823

RESUMO

Coxiella burnetti is an intracellular bacterium that causes Q fever, a disease of worldwide importance. Q-VAX® , the approved human Q fever vaccine, is a whole cell vaccine associated with safety concerns. Here a safe particulate subunit vaccine candidate is developed that is ambient-temperature stable and can be cost-effectively manufactured. Endotoxin-free Escherichia coli is bioengineered to efficiently self-assemble biopolymer particles (BPs) that are densely coated with either strings of 18 T-cell epitopes (COX-BP) or two full-length immunodominant antigens (YbgF-BP-Com1) all derived from C. burnetii. BP vaccine candidates are ambient-temperature stable. Safety and immunogenicity are confirmed in mice and guinea pig (GP) models. YbgF-BP-Com1 elicits specific and strong humoral immune responses in GPs with IgG titers that are at least 1 000 times higher than those induced by Q-VAX® . BP vaccine candidates are not reactogenic. After challenge with C. burnetii, YbgF-BP-Com1 vaccine leads to reduced fever responses and pathogen burden in the liver and the induction of proinflammatory cytokines IL-12 and IFN-γ inducible protein (IP-10) when compared to negative control groups. These data suggest that YbgF-BP-Com1 induces functional immune responses reducing infection by C. burnetii. Collectively, these findings illustrate the potential of BPs as effective antigen carrier for Q fever vaccine development.


Assuntos
Coxiella burnetii , Febre Q , Humanos , Animais , Camundongos , Cobaias , Febre Q/prevenção & controle , Coxiella burnetii/metabolismo , Vacinas Bacterianas , Imunidade , Vacinas de Subunidades/metabolismo
15.
Eur J Clin Microbiol Infect Dis ; 43(4): 649-657, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38270806

RESUMO

PURPOSE: Fever of intermediate duration (FID) is defined as a fever in the community without a specific origin or focus, with a duration between 7 and 28 days. FID is often caused by pathogens associated with animal contact or their arthropods parasites, such as ticks, fleas, or lice. The purpose of this work is to design a collection of molecular tools to promptly and accurately detect common bacterial pathogens causing FID, including bacteria belonging to genera Rickettsia, Bartonella, Anaplasma, and Ehrlichia, as well as Coxiella burnetii. METHODS: Reference DNA sequences from a collection of Rickettsia, Bartonella, Anaplasma, and Ehrlichia species were used to design genus-specific primers and FRET probes targeted to conserved genomic regions. For C. burnetii, primers previously described were used, in combination with a newly designed specific probe. Real-time PCR assays were optimized using reference bacterial genomic DNA in a background of human genomic DNA. RESULTS: The four real-time PCR assays can detect as few as ten copies of target DNA from those five genera of FDI-causing bacteria in a background of 300 ng of human genomic DNA, mimicking the low microbial load generally found in patient's blood. CONCLUSION: These assays constitute a fast and convenient "toolbox" that can be easily implemented in diagnostic laboratories to provide timely and accurate detection of bacterial pathogens that are typical etiological causes of febrile syndromes such as FID in humans.


Assuntos
Bartonella , Coxiella burnetii , Rickettsia , Animais , Humanos , Rickettsia/genética , Bartonella/genética , Ehrlichia/genética , Coxiella burnetii/genética , Anaplasma/genética , DNA
16.
Nat Commun ; 15(1): 697, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38267444

RESUMO

Lipopolysaccharide (LPS) phase variation is a critical aspect of virulence in many Gram-negative bacteria. It is of particular importance to Coxiella burnetii, the biothreat pathogen that causes Q fever, as in vitro propagation of this organism leads to LPS truncation, which is associated with an attenuated and exempted from select agent status (Nine Mile II, NMII). Here, we demonstrate that NMII was recovered from the spleens of infected guinea pigs. Moreover, these strains exhibit a previously unrecognized form of elongated LPS and display increased virulence in comparison with the initial NMII strain. The reversion of a 3-bp mutation in the gene cbu0533 directly leads to LPS elongation. To address potential safety concerns, we introduce a modified NMII strain unable to produce elongated LPS.


Assuntos
Coxiella burnetii , Animais , Cobaias , Coxiella burnetii/genética , Lipopolissacarídeos , Mutação , Reprodução , Baço
17.
Comp Immunol Microbiol Infect Dis ; 106: 102127, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38277904

RESUMO

In addition to zoonotic viral pathogens, bats can also harbor bacterial pathogens, including hemoplasmas (hemotropic mycoplasmas) and Coxiella burnetii. The present study aimed to investigate, using molecular techniques, the presence of hemoplasmas and C. burnetii in spleen samples from vampire bats in northern Brazil. For this purpose, between 2017 and 2019, spleen samples were collected from Desmodus rotundus (n = 228) and Diaemus youngii (n = 1) captured in the states of Pará (n = 207), Amazonas (n = 1), Roraima (n = 18) and Amapá (n = 3). DNA samples extracted from the bat spleen and positive in PCR for the endogenous gapdh gene were subjected to conventional PCR assays for the 16S rRNA, 23S rRNA and RNAse P genes from hemoplasmas and to qPCR based on the IS1111 gene element for C. burnetii. All spleen samples from vampire bats were negative in the qPCR for C. burnetii. Hemoplasmas were detected in 10 % (23/229) of spleen samples using a PCR based on the 16S rRNA gene. Of these, 21.73 % (5/23) were positive for the 23S rRNA gene and none for the RNAseP gene. The seven hemoplasma 16S rRNA sequences obtained were closely related to sequences previously identified in vampire bats from Belize, Peru and Brazil. The 23S rRNA sequence obtained revealed genetic proximity to hemoplasmas from non-hematophagous bats from Brazil and Belize. The analysis revealed different circulating genotypes among Brazilian vampire bats, in addition to a trend towards genera-specific hemoplasma genotypes. The present study contributes to the knowledge of the wide diversity of hemoplasmas in vampire bats.


Assuntos
Quirópteros , Coxiella burnetii , Infecções por Mycoplasma , Animais , Infecções por Mycoplasma/microbiologia , Infecções por Mycoplasma/veterinária , Quirópteros/microbiologia , Brasil/epidemiologia , Coxiella burnetii/genética , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética , Filogenia
18.
Prev Vet Med ; 223: 106114, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38198901

RESUMO

Infection with the bacterium Coxiella burnetii can cause coxiellosis in animals and Q fever in humans. Coxiellosis a consistently underreported infectious disease. The infection can result in reproductive consequences for humans and animals. Ruminants are a reservoir for infection and humans are generally infected via aerosolized secretions, making it a public health concern. Studies of ruminant seroprevalence are generally limited in size and scope. This study determined seroprevalence in a large-scale U.S. population of female goats using serum samples from 7736 does from 24 states. This study identified C. burnetii seroprevalence in the United States domestic goat population. Overall, 14.5 % (SE = 2.3) of does were seropositive and 21.0 % (SE = 2.4) of operations had at least 1 seropositive doe. Further, operation demographics and herd management practices associated with seropositivity were as follows: the suspected or confirmed presence of caprine arthritis encephalitis (CAE), caseous lymphadenitis (CL), Johne's disease, or sore mouth in the herd in the previous 3 years, not cleaning or disinfecting the kidding areas or removing aborting does from other does, allowing visitors to access the kidding areas, and a lower percentage of adult goat inventory that were adult bucks or wethers. Furthermore, goat breed was associated with seropositivity. These data show C. burnetii seroprevalence in the United States and identify operation and animal characteristics and management practices associated with C. burnetii seropositivity. Together, this information can be used to help limit animal transmission, inform public health measures, and help educate and protect individuals working with goats.


Assuntos
Coxiella burnetii , Doenças das Cabras , Febre Q , Doenças dos Ovinos , Humanos , Animais , Masculino , Feminino , Estados Unidos/epidemiologia , Ovinos , Cabras , Estudos Soroepidemiológicos , Prevalência , Doenças das Cabras/epidemiologia , Doenças das Cabras/microbiologia , Febre Q/epidemiologia , Febre Q/veterinária , Febre Q/microbiologia , Ruminantes , Fatores de Risco , Doenças dos Ovinos/epidemiologia
19.
Am J Trop Med Hyg ; 110(1): 155-158, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-37983923

RESUMO

Coxiella burnetii is an underreported zoonotic pathogen in many rural regions globally. We investigated C. burnetii exposure in a remote indigenous tribe residing in the Sierra Nevada de Santa Marta, Colombia. The high seroprevalence of 35% (95% CI, 27-43%) demonstrates the need for One Health studies to identify risk factors, clinical impact, and potential medical, veterinary, and environmental interventions.


Assuntos
Coxiella burnetii , Febre Q , Humanos , Colômbia/epidemiologia , Estudos Soroepidemiológicos , Fatores de Risco , Povos Indígenas , Febre Q/epidemiologia
20.
Comp Immunol Microbiol Infect Dis ; 104: 102097, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38029723

RESUMO

The role of wildlife in the complex balance of tick-borne diseases within ecosystems is crucial, as they serve as hosts for tick carriers and reservoirs for the pathogens carried by these ticks. This study aimed to investigate the presence of zoonotic pathogenic bacteria in wildlife, specifically in hares and long-eared hedgehogs (Hemiechinus megalofis), in the eastern region of Iran. The focus was on the detection of Borrelia spp., Coxiella burnetii, Anaplasma spp., Francisella spp., and Leptospira spp., using the Nested-PCR method. We analyzed a total of 124 blood samples, and 196 ticks collected from hares and long-eared hedgehogs were analyzed. The Nested-PCR method was employed to identify the presence of zoonotic pathogenic bacteria DNA. Our study revealed the presence of these zoonotic pathogenic bacteria in both wildlife species, indicating their potential role as hosts and reservoirs for the ticks carrying these pathogens. The specific presence and prevalence of Borrelia spp., Coxiella burnetii, Anaplasma spp., Francisella spp., and Leptospira spp. were determined through the Nested-PCR method. This study contributes to the limited knowledge about the involvement of wild animals in the transmission of tick-borne diseases. By using the Nested-PCR method, we successfully identified the presence of zoonotic pathogenic bacteria in hares and long-eared hedgehogs. This study emphasizes the need for further research to better understand the ecological process of tick-borne diseases, particularly the role of wildlife in their spread. Such knowledge is crucial for wildlife conservation efforts and the management of tick-borne diseases, ultimately benefiting both animal and human health.


Assuntos
Borrelia , Coxiella burnetii , Francisella , Lebres , Rickettsia , Doenças Transmitidas por Carrapatos , Carrapatos , Animais , Humanos , Carrapatos/microbiologia , Ecossistema , Irã (Geográfico)/epidemiologia , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/veterinária , Doenças Transmitidas por Carrapatos/microbiologia , Animais Selvagens/microbiologia , Coxiella burnetii/genética , Anaplasma/genética , Francisella/genética , Rickettsia/genética
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