Detection of Rickettsia raoultii in Vermipsylla alakurt-Like Fleas of Sheep in Northwestern China.

INTRODUCTION: To date, a total of 2574 validated flea species have been discovered. Vermipsyllidae is a family of fleas that comprises at least eight species. Vermipsylla is a genus of the family Vermipsyllidae within the order Siphonaptera of fleas. Here a novel Vermipsylla species was described, and rickettsial agent was also detected in it. METHODS: A total of 128 fleas were collected directly from 260 pastured sheep in China. Of these, eight representative fleas (four males and four females) were identified by key morphological features. Meanwhile, 120 flea DNAs, including six flea samples for molecular taxonomy, were subjected to Rickettsia spp. DNA detection. The molecular identity of fleas was determined by amplification and sequenmce analysis of four genetic markers (the 28S rDNA genes, the 18S rDNA genes, the mitochondrial cytochrome c oxidase subunit I and subunit II). In addition, five Rickettsia-specific gene fragments were used to identify the species of the rickettsial agents. The amplified products were sequenced and phylogenetically analyzed. RESULTS: The morphological characteristics of the flea species identified in this study were similar to Vermipsylla alakurt, but presented difference in hair number of the metepimeron, the third tergum, the genitals and the tibiae of hind leg. The 18S rDNA, 28S rDNA and COII genetic markers from fleas showed the highest identity to those of V. alakurt, shared 98.45% (954/969), 95.81% (892/931) and 85.86% (571/665) similarities, respectively. However, the COI sequence showed the highest identity to that of Dorcadia ioffi with 88.48% (576/651) similarity. Rickettsia raoutii tested positive in 14.17% (17/120) flea DNA samples. CONCLUSION: Our study reports the detection of R. raoultii in V. alakurt-like fleas infesting sheep in China.

Comparison of hematologic and serum biochemical variables in Brucella-infected and Brucella-free adult Himalayan marmots (Marmota himalayana).

BACKGROUND: The Himalayan marmot (Marmota himalayana) plays a reservoir role in the epidemiology of brucellosis. However, the changes in blood biochemical parameters are still unclear in Brucella-seropositive marmots. OBJECTIVES: The present study was designed to explore the hematologic and biochemical variable changes in Brucella-seropositive marmots. METHODS: Blood samples were collected from the dorsalis pedis vein of Himalayan marmots (24 Brucella-seropositive marmots and 24 Brucella-free marmots). Ten hematologic and 10 serum biochemical variable examinations were performed and analyzed. RESULTS: Our results showed that leukocyte, platelet, neutrophil, and lymphocyte counts significantly increased, while the level of carbon dioxide combining power decreased in Brucella-infected marmots. These findings indicate that Brucella triggers an immune response in Himalayan marmots. CONCLUSIONS: This study provides a preliminary investigation of the changes in blood biochemical analytes in Brucella-infected marmots. The interaction between Brucella infection and blood biochemical indices in Himalayan marmots should be further explored.

Influenza vaccine effectiveness against influenza A during the delayed 2022/23 epidemic in Shihezi, China.

After the temporary end of COVID-19 in China in February 2023, the influenza epidemic peaked in March across many Chinese places. We recruited a total of 258 all-age subjects presenting influenza-like illness (ILI) in Shihezi city, China from January 1 to March 16, 2023, and tested for influenza virus infection. Using a test-negative design, we assessed influenza vaccine effectiveness (VE) of 56.3% (95% CrI: 13.6, 73.6) against medically attended, influenza illness during the delayed 2022/23 influenza epidemic. The findings contributed to the continuous monitoring of the influenza vaccine performance across the world, especially in the "post-COVID" pandemic era.

Rickettsia aeschlimannii Infection in a Woman from Xingjiang, Northwestern China.

Tick-borne Rickettsia aeschlimannii infection in humans has been described in several countries. This is the first report of R. aeschlimannii in a woman who reported being bitten by ticks in Xingjiang, northwestern China. R. aeschlimannii infection was confirmed by molecular detection in blood and urine of the patient, who presented clinical symptoms of severe edema, partial necrosis, and monocytosis. R. aeschlimannii was also detected in Hyalomma asiaticum ticks around the patient's residence. Infections of spotted fever group Rickettsia species should be included in the differential diagnosis from other tick-borne diseases.

A tick bite patient with fever and meningitis co-infected with Rickettsia raoultii and Tacheng tick virus 1: a case report.

BACKGROUND: Increasing numbers of tick-borne pathogens are being discovered, including those that infect humans. However, reports on co-infections caused by two or more tick-borne pathogens are scarce. CASE PRESENTATION: A 38-year-old male farmer was bitten by a hard tick, presented with fever (37.7 °C), severe headache and ejection vomiting. Lumbar puncture was performed in the lateral decubitus. The cerebrospinal fluid (CSF) was clear, and analysis showed severe increased pressure (320 mm H2O), mild leukocytosis (126.0 × 106/L, mononuclear cells accounting for 73%) and elevated total protein concentration (0.92 g/L). Bacterial cultures of CSF and blood were negative. The diagnosis of Rickettsia raoultii and Tacheng tick virus 1 (TcTV-1) co-infection was confirmed by amplifying four rickettsial genetic markers and the partial small (S) RNA segment of TcTV-1 from the patient's blood. The patient gradually recovered after treatment with levofloxacin and ribavirin. CONCLUSIONS: This is the first reported co-infection case with fever and meningitis caused by R. raoultii and TcTV-1. It is vital to screen for multiple pathogens in tick-bitten patients, especially in those with severe complex symptoms.

Short- and long-term follow-up outcomes of patients with Brucella endocarditis: a systematic review of 207 Brucella endocarditis Cases.

Brucella endocarditis is a fatal complication and the most frequent cause of death for human brucellosis. This study aimed to systematically review the literature on the follow-up outcomes of Brucella endocarditis and analyze the determinants affecting the follow-up outcomes. The databases PubMed, Web of Science, Embase, and Cochrane were searched using keywords and suitable combinations. All studies reporting the follow-up outcomes of Brucella endocarditis were included. Finally, a total of 76 studies (207 patients), including cases or case series, were included. The event rate for patients who underwent short- and long-term follow-up was 12.0% (2 relapsed and 1 died) and 8.1% (6 relapsed and 8 died), respectively. The differences in outcomes between different age groups (18-39, 40-59, and ≥60) were significant (P < 0.05, P = 0.035). The outcomes of the 18-39 age group were worse than those of the 40-59 age group (OR, 0.277; 95% CI, 0.103-0.748; P = 0.011). Accordingly, follow-up (both short- and long-term follow-up) is essential for Brucella endocarditis patients, especially for younger patients (18-39 years) in the first 6 months after treatment. The burden of Brucella endocarditis related complications were immense. Further studies are needed to explore age-based epidemiology of Brucella endocarditis and the exact influencing factors of the follow-up outcomes.

A case report of endocarditis and spondylitis caused by Brucella melitensis biovar 3.

BACKGROUND: This case report describes the clinical process of a shepherd who suffered brucellosis-related endocarditis (BE) and spondylitis (BS) and was infected with Brucella melitensis biovar 3 (B. melitensis biovar 3). CASE PRESENTATION: A 55-year-old male patient was admitted to The First Affiliated Hospital of Shihezi University on October 11, 2018, due to over 3 months of intermittent fever, back pain, and heart trouble. The Rose Bengal Plate test was positive, the standard agglutination test titer for brucellosis was 1/800, and the blood culture was positive for B. melitensis biovar 3. Three instances of transthoracic echocardiography examination at days 1, 25, and 376 after admission to the hospital and magnetic resonance imaging (MRI) and computed tomography (CT) checks at days 5 and 38 revealed that the size of the vegetation on the posterior leaflet of the mitral valve increased from 0.7 × 1.4 cm to 1.2 × 1.5 cm and that the left atrium and ventricle were enlarged. The MRI and CT results showed hyperplasia of the second and third vertebra, a cold abscess formed on both sides of the psoas major muscles, and the vertebra hyperplasia became aggravated at a later time point. The patient's situation deteriorated, and heart failure was discovered on October 22, 2019. At the moment of submission of this manuscript, the patient remains in bed at home because of severe debility caused by brucellosis. CONCLUSIONS: This is the first reported case of endocarditis combined with spondylitis caused by B. melitensis biovar 3 in a shepherd. Brucellosis infection can cause work-power losses because of misdiagnosis or a lack of proper treatment. Early diagnosis and treatment are essential for a successful outcome.

Human Tacheng Tick Virus 2 Infection, China, 2019.

We used metagenomic analysis to identify Tacheng tick virus 2 infection in a patient with a history of tick bite in northwestern China. We confirmed the virus with reverse transcription-PCR, virus isolation, and genomic analysis. We detected viral RNA in 9.6% of ticks collected from the same region.

Brucellar reproductive system injury: A retrospective study of 22 cases and review of the literature.

OBJECTIVE: We aimed to describe the clinical characteristics and prognosis of 22 patients with Brucella-induced reproductive system injury. METHODS: We assessed 22 patients with reproductive system injury between 2010 and 2018 at The First Affiliated Hospital of Xinjiang Medical University. RESULTS: The disease is predominant in men. Male patients had orchitis, erectile dysfunction, prostatitis, and urethral stricture, while female patients had vaginitis and cervicitis. Some patients had laboratory abnormalities and liver injury. Patients received combination therapy of rifampicin and doxycycline. Doxycycline combined with levofloxacin or moxifloxacin was administered to patients with rifampicin intolerance. All patients had received antibiotic therapy for at least 6 weeks. One patient was lost to follow-up, one patient relapsed because of osteoarthropathy, and one patient had dysuria resulting from chronic prostatitis. The clinical symptoms resolved in the other patients, and the overall patient prognosis was good. CONCLUSION: Clinicians should pay attention to brucellosis-induced reproductive system damage. The two-drug regimen of rifampicin+doxycycline is recommended for these patients. Doxycycline combined with levofloxacin or moxifloxacin should be used in patients with brucellosis-induced reproductive system damage who have rifampicin intolerance. The treatment course should be at least 6 weeks.

A Tentative Tamdy Orthonairovirus Related to Febrile Illness in Northwestern China.

BACKGROUND: Many novel tick-borne viruses have been discovered by deep-sequencing technology in recent years; however, their medical significance is unknown. METHODS: We obtained clinical data of a patient from Xinjiang, China. Possible pathogens were detected by metagenomic analysis; the causative pathogen Tacheng tick virus 1 (TcTV-1) was found and further confirmed by reverse transcriptase-polymerase chain reaction, viral culture, and sequence analyses. Epidemiological investigation was conducted in the local human population, domestic animals, and ticks by serological/molecular methods. RESULTS: A 62-year-old woman with a history of tick bite in Qinghe, Xinjiang, presented with fever and rashes. These symptoms were relieved after clinical treatment. TcTV-1 (strain QH1) was isolated from the patient's cerebrospinal fluid, throat swabs, and urine on day 47 after illness onset. Although the blood and urine showed viral RNA positive on day 73 after illness onset, the virus was only isolated from urine. Serological detection revealed a virus neutralizing antibody titer of 1:40 and 1:80 on day 47 and 73 after illness onset, respectively. No coinfection with other pathogens was detected, suggesting TcTV-1 may be the potential causative pathogen. We detected anti-TcTV-1 antibodies (immunoglobulin G: 10.1%; immunoglobulin M: 4.8%) in the local human population. The viral RNA was also found in cattle (4.9%), sheep (9.2%), and ticks, including Dermacentor marginatus (14.3%), Dermacentor silvarum (11.8%), Dermacentor nuttalli (6.7%), and Hyalomma asiaticum (4.8%). CONCLUSIONS: TcTV-1 may be associated with a febrile illness syndrome, and epidemiological data of the virus in humans and animals necessitate disease surveillance of TcTV-1 infection in China.

A case with neurological abnormalities caused by Rickettsia raoultii in northwestern China.

BACKGROUND: The number of new rickettsial species are rapidly increasing, and increasing numbers of Rickettsia raoultii (R. raoultii) infection cases have been detected in humans. However, neurological abnormalities caused by R. raoultii are rarely reported, especially in northwestern China. CASE PRESENTATION: A 36-year-old Kazakh shepherd with an attached tick on part temporalis, presented with right eyelid droop, lethargy, fever, headache, fever (38.0-41.0 °C) and erythematous rash. The examination of cerebrospinal fluid (CSF) showed cerebrospinal pressure of 200 mm H2O, leukocyte count of 300.0 × 106/L, adenosine deaminase of 2.15 U/L, and total protein concentration of 0.93 g/L. The diagnosis of R. raoultii infection was confirmed by six genetic markers, and semi-quantified by enzyme-linked immunosorbent assay for rickettsial antigen. The patient gradually recovered after treatment with doxycycline and ceftriaxone. R. raoultii DNA was found both in a tick detached from this patient and in 0.18% (2/1107) of blood samples collected from local shepherds. CONCLUSIONS: This is the first reported case with neurological abnormalities caused by R. raoultii in northwestern China. It is vital to detect rickettsial agents both in blood and CSF for tick bite patients with neurological abnormalities. Public health workers and physicians should pay attention to neurological abnormalities caused by Rickettsia.

Circulating Th1, Th2, Th17, Treg, and PD-1 Levels in Patients with Brucellosis.

Brucella is an intracellular infection bacterium; the pathogenesis of Brucella and chronicity of infection may be related to the immune response of T cells. T lymphocytes mainly participate in cellular immune response. The extent of different T cell subsets imbalanced and their function dysregulated in patients with brucellosis remain not explicit. We grouped patients at different stages (acute, chronic, and convalescent). The frequencies of Th1, Th2, Th17, Treg, and PD-1 (programmed cell death protein 1) in peripheral blood were examined by flow cytometry, and the expressions of T lymphocyte cytokines in serum were detected by cytometric bead array. Th1, Th17, and Treg cell immunity was predominant in the acute stage, while Th2, Th17, and Treg cell immunity was predominant in the chronic stage. The expressions of PD-1 on CD4+ and CD8+ T lymphocytes were significantly different in acute and chronic patients. The percentages of Th1 cells in convalescent patients were still higher than those in healthy controls within one year after withdrawal. The expression of T lymphocyte cytokines in serum was different in patients at different stages. These results indicate that peripheral T lymphocyte immunity was involved in patients with brucellosis and represents a target for the preclinical and clinical assessment of novel immunomodulating therapeutics. The patients' immune function had not completely recovered in a short period of time during convalescence, so long-term follow-up of convalescent patients is needed.

Childhood pneumonia due to brucellosis: A case report.

RATIONALE: Childhood brucellosis is a significant community health problem. It may imitate other conditions and may be misdiagnosed. Pulmonary involvement is a rare complication of childhood brucellosis. PATIENT CONCERNS: A 23-month-old child was referred to our hospital with a 3-week history of fevers and cough. He was initially diagnosed with pneumonia. DIAGNOSES AND INTERVENTIONS: Conventional antibiotic treatment was ineffectual. Total leukocyte count was 10,300/mm, hemoglobin was 8.5 g/dL, and platelet count was 250,000/mm. The erythrocyte sedimentation rate and procaicltonin were 25 mm/h and 0.12 ng/mL, respectively. Chest radiography showed pneumonic infiltrate in both lungs.The initial bacteriologic test results were negative. Ten days after admission, Brucella melitensis were isolated from the second blood culture. This child was cured with the 2-drug regimen (rifampin+trimethopicin-sulfamethoxazole) for 6 weeks. OUTCOMES: The child recovered well with no occurrence of complications. The child remained asmptomatic without any signs or symptoms at a follow-up of 1 year. LESSONS: Non-specific findings of pulmonary brucellosis in children often make diagnosis difficult. The second blood culture is essential. In endemic areas, children with fevers and cough should be included in the diagnosis in cases of pulmonary brucellosis.

Meta-Analysis of the Changes of Peripheral Blood T Cell Subsets in Patients with Brucellosis.

Brucellosis is one of the most prevalent zoonotic diseases in the world, but its pathogenesis is not very clear. At present, it is thought that it may be related to the immunity of T cells. The conclusions of related studies are inconsistent, and its clinical significance is not explicit. We searched published articles in electronic databases up to December 2017 identified as relating to the clinical features of human brucellosis in China. Only eight studies had sufficient quality for data extraction. Meta-analysis showed a significantly decreased proportion of CD4+ T cells in human brucellosis patients compared to healthy subject individuals. The frequency of CD8+ T cells was significantly higher in human brucellosis patients than that in the healthy control group. The pooled analysis presented a significant decrease of the CD4+/CD8+ ratio in human brucellosis patients compared to healthy subjects. There is immunologic dysfunction of T lymphocyte in patients with human brucellosis, the CD4+ and CD8+ T cells might be the important factors affecting the progress of brucellosis.

A Systematic Review and Meta-Analysis of Epidemiology and Clinical Manifestations of Human Brucellosis in China.

Background. Brucellosis has a wide spectrum of clinical manifestations and it may last several days or even several years; however, it is often misdiagnosed and therefore may cause inadequate therapy and prolonged illness. Previous studies about meta-analysis of manifestations of brucellosis reported in English lacked the data published in Chinese, which did not provide details about the contact history, laboratory tests, and misdiagnosis. We undertake a meta-analysis of clinical manifestations of human brucellosis in China to identify those gaps in the literature. We have searched published articles in electronic databases up to December 2016 identified as relating to clinical features of human brucellosis in China. 68 studies were included in the analysis. The main clinical manifestations were fever, fatigue, arthralgia, and muscle pain (87%, 63%, 62%, and 56%, resp.). There are significant differences between adults and children. Rash, respiratory and cardiac complications, and orchitis/epididymitis were more prevalent in children patients. The common complications of brucellosis were hepatitis, followed by osteoarthritis, respiratory diseases, cardiovascular diseases, central nervous system dysfunction, hemophagocytic syndrome, and orchitis/epididymitis in male. In the nonpastoral areas, brucellosis has a high ratio of misdiagnosis. Our analysis provides further evidence for the accurate diagnosis, particularly in assessing severe, debilitating sequelae of this infection.

Brucella melitensis and B. abortus in eggs, larvae and engorged females of Dermacentor marginatus.

Brucellosis is a relatively common zoonosis, particularly in the developing countries. Our aim was to cultivate the Brucella wild-type strain from eggs of Dermacentor marginatus, and to molecularly investigate the presence of Brucella DNA in different developmental stages. A total of 350 engorged adult female ticks were collected from sheep and cattle, and individually placed into a single clean breathable tube suitable for laying eggs and for the development of larvae. Detection of Brucella DNA was attempted in engorged female ticks and their offsprings based on the Brucella outer membrane protein gene 22 (omp22) and IS711 gene. Additionally, bacterial isolation in the culture medium of Brucella was performed. The eggs from the Brucella DNA-positive engorged female ticks were positive for Brucella omp22 (4.6%, 16/350). The prevalence was 40.9% (90/220) in larvae, which developed from the Brucella DNA-positive egg batch. Based on BLASTn analysis of IS711 gene, ten (4.1%, 10/242) PCR products were identified as Brucella melitensis in D. marginatus from sheep, while six (5.6%, 6/108) were identified as B. abortus in D. marginatus infesting cattle. B. melitensis biotype 3 was isolated from eggs of D. marginatus. This is the first study which demonstrates the transovarial transmission of Brucella in the D. marginatus. Furthermore, Brucella may be partially transmitted from D. marginatus eggs to larvae (40.9%) in D. marginatus. These findings extend our knowledge on the transmission of Brucella in D. marginatus offsprings.