Urban zoonoses caused by Bartonella,Coxiella, Ehrlichia,and Rickettsia species

The last half of the 20th Century witnessed an increase in the occurrence and recognition of urban zoonoses caused by members of the genera Bartonella, Coxiella, Ehrlichia, and Rickettsia, all traditionally considered to be members of the family Rickettsiaceae. In recent years, new human pathogens (Bartonella elizabethae, Bartonella henselae, and Rickettsia felis) have been recognized in urban environments. Other newly recognized pathogens (Ehrlichia chaffeensis and Ehrlichia phagocytophila in the United States) have sylvan zoonotic cycles but are present in urban areas because their vertebrate hosts and associated ectoparasitic arthropod vectors are able to survive in cities. Still other agents, which were primarily of historical importance (Bartonella quintana) or have not traditionally been associated with urban environments (Rickettsia rickettsii), have been recognized as causes of human disease in urban areas. Some diseases that have traditionally been associated with urban environments, such as rickettsialpox (caused by Rickettsia akari) and murine typhus (caused by Rickettsia typhi), still occur in large cities at low or undetermined frequencies and often go undetected, despite the availability of effective measures to diagnose and control them. In addition, alternate transmission cycles have been discovered for Coxiella burnetii, Rickettsia prowazekii, and R. typhi that differ substantially from their established, classic cycles, indicating that the epidemiology of these agents is more complex than originally thought and may be changing. Factors leading to an increase in the incidence of illnesses caused by these bacteria in urban areas include societal changes as well as intrinsic components of the natural history of these organisms that favor their survival in cities. Transovarial and transstadial transmission of many of the agents in their arthropod hosts contributes to the highly focal nature of many of the diseases they cause by allowing the pathogens to persist in areas during adverse times when vertebrate amplifying hosts may be scarce or absent. Domesticated animals (primarily cats, dogs, and livestock) or commensal rodents [primarily Norway rats (Rattus norvegicus) and house mice (Mus musculus)] can serve as vertebrate amplifying hosts and bring these agents and their ectoparasitic arthropod vectors into direct association with humans and help maintain transmission cycles in densely populated urban areas. The reasons for the increase in these urban zoonoses are complex. Increasing population density worldwide, shifts in populations from rural areas to cities, increased domestic and international mobility, an increase in homelessness, the decline of inner-city neighborhoods, and an increase in the population of immunosuppressed individuals all contribute to the emergence and recognition of human diseases caused by these groups of agents. Due to the focal nature of infections in urban areas, control or prevention of these diseases is possible. Increased physician awareness and public health surveillance support will be required to detect and treat existing urban infections caused by these agents, to determine the disease burden caused by them, to design and implement control programs to combat and prevent their spread, and to recognize emerging or resurging infections caused by members of these genera as they occur.     

Infections in Patients With End-stage Liver Disease

Infections in patients with end-stage liver disease (ESLD) are an important cause of morbidity and mortality in these patients. Abnormalities in their natural defense mechanisms, alterations in the enteric flora and the growing utilization of invasive procedures increase the risk of infections in these patients. Common bacterial infections in ESLD patients include spontaneous bacterial peritonitis, urinary tract infections, community-acquired pneumonia, dermatologic infections, and bacteremia. Viral infections such as influenza can have a devastating course in ESLD patients. Hepatitis B and C are now among the most common causes of ESLD. They also present an important therapeutic challenge. As patients with human immunodeficiency virus are surviving longer, ESLD due to hepatitis C is now emerging as a leading cause of morbidity in these patients. Prompt detection of infections, use of appropriate antibiotics for treatment and prophylactic measures such as vaccinations can help improve survival in these patients.     

Bartonella species in small mammals and their ectoparasites in Taiwan

Bartonella spp. prevalence in small mammals and their ectoparasites was investigated in Taiwan. Blood samples were obtained from 66 rats, 20 shrews, 276 mites (Laelaps spp.), 74 fleas (Xenopsylla cheopis), 81 lice (Polyplax spp.), and 47 ticks (41 Dermacentor spp. and 6 Ixodes spp.). Bartonellae were isolated or detected in 27 (31.4%) animals. Bartonella DNA was detected in 48 (64.9%) fleas and 11 (64.7%) pooled lice samples, but not in mite and tick samples. Bartonella phoceensis, B. queenslandensis, B. tribocorum, B. elizabethae, and B. rattimassiliensis were isolated or detected in bacteremic mammals. For the first time in Taiwan, B. tribocorum, B. elizabethae, B. queenslandensis, and a B. rochalimae-like strain were detected in fleas, and B. tribocorum, B. phoceensis, and B. rattimassiliensis were detected in lice obtained from small mammals. A broader range of Bartonella species was identified in the ectoparasites than in the small mammals.     

Cat scratch disease (bartonellosis) mimicking an SLE flare.

Only recently Bartonella species have been recognized as important human pathogens. Cat scratch disease (CSD), caused by infection with Bartonella henselae, shows a steady increase in the number of cases throughout the world. We report a case of an 18-year-old woman with systemic lupus erythematosus (SLE) who presented with ongoing fever, arthralgias and loss of weight which did not respond to increasing doses of corticosteroids. After exclusion of common infections a photograph of her cat in combination with scratch marks on her arms finally led to the suspicion of CSD. This tentative diagnosis was confirmed serologically. Under clarithromycin treatment the patient rapidly responded and her temperature dropped within 2 days.     

巴尔通体的流行病学

巴尔通体为革兰阴性菌,可通过媒介昆虫白蛉、跳蚤、体虱传播,致人巴尔通体病。主要表现为奥罗亚热和秘鲁疣、猫抓病、五日热、杆菌性血管瘤等。本文综述了巴尔通体的流行病学。     

Infection and angiomatous cutaneous lesions]

The occurrence of angiomatous cutaneous lesions in the presence of an infective process is not a frequent phenomenon. Most infectious diseases are associated with an exanthematous reaction. The combination of an infective illness and angiomatous lesions is seen essentially in the bartonelloses and in Kaposi's disease. Bartonelloses: group of infections due to alpha-proteobacteria such as Bartonella. Bartonella bacilliformis (BB), is the causal agent of Carrion's disease, the chronic cutaneous form of which (verruga peruana), in which the vector is an arthropod of the Lutzomyia species found in South America, presents superficial and deep angiomatous cutaneous nodules. Spontaneous regression occurs in a few months or years. Bartonella henselae (BH) and Bartonella quintana (BQ), are the causal agents of bacillary angiomatosis (BA), described in 1983, in which angiomatous papules or nodules with an appearance like botryomycomas, are associated with visceral lesions. The characteristic histological features (with the demonstration or the bacilli by Warthin-Starry stain) together with culture of the bacterium in various tissues (including the blood) are diagnostic. BA occurs most commonly, but not exclusively, in patients with HIV infection. Furthermore, BH is responsible for cat scratch disease while BQ causes trench fever. The reservoir of BH is the cat. The bartonella produce angiogenic factors responsible for the neovascularisation seen in angiomatous lesions. The differential diagnosis is between botryomycomas and Kaposi's disease. Numerous antibiotics are effective against botryomycomas, particularly chloramphenicol and penicillin for BB and macrolides, cyclins and fluoroquinolones for BH and BQ. Kaposi's disease (KD): whether classical, endemic or epidemic (due to HIV infection) is characterised by cutaneous and visceral angiomatous lesions: these are associated with multifocal tumorous proliferations (of endothelial and fusiform cells) affected by angiogenic growth factors (PDGF, FGF, IL6, alphaTGF, HIVtat, androgens) and strongly linked to the lymphocytic and endothelial tropism of a gamma herpes virus (HHV8, Chang and Moore 1994). HHV8 infection, probably sexually transmitted, is also the cause of lymphomas occurring in cavities and of Castleman's disease. The course of KD is very variable: from the indolent form in elderly HIV-ve patients, to the explosive forms in the immunodepressed (particularly in HIV+ve patients.     

Bartonellosis and a possible role of Ixodes ticks (family Ixodidae, order Parasitiformes) in the transmission of pathogenic Bartonella bacteria

The papers reviews the literature on bartonellosis and a role of Ixodes ticks, including the representatives of the genus Ixodes, in the circulation and transmission of Bartonella bacteria. It shows that man can be infected with pathogenic Bartonella bacteria by the bite of ticks. The paper also presents data on tick-transmitted human and animal mixed infections, including bartonellosis.     

Association of Bartonella species and Coxiella burnetii infection with coronary artery disease

Coronary artery disease is an inflammatory condition associated with several infections. We prospectively evaluated 155 consecutive patients undergoing coronary angiography for evidence of Bartonella species and Coxiella burnetii infection. All Bartonella cultures were found to be negative. Multivariable logistic regression analysis that controlled for potential confounding factors revealed no association between coronary artery disease and seropositivity to Bartonella henselae (odds ratio [OR], 0.852; 95% confidence interval [CI], 0.293-2.476), Bartonella quintana (OR, 0.425; 95% CI, 0.127-1.479), C. burnetii phase 1 (OR, undefined), and C. burnetii phase 2 (OR, 0.731; 95% CI, 0.199-2.680). The geometric mean titer (GMT) for C. burnetii phase 1 assay was slightly higher in persons with coronary artery disease than in those without such disease (P<.02). B. henselae, B. quintana, and C. burnetii seropositivity was not strongly associated with coronary artery disease. On the basis of GMTs, C. burnetii infection may have a modest association with coronary artery disease.     

Bartonella infection in shelter cats and dogs and their ectoparasites

Mainly through vector transmission, domestic cats and dogs are infected by several Bartonella spp. and represent a large reservoir for human infections. This study investigated the relationship of prevalences of Bartonella infection in shelter dogs and cats and various ectoparasite species infesting them (fleas, ticks, and lice). Moreover, relationships between Bartonella infection and animal gender and age and presence of ectoparasites were analyzed. Blood samples were collected from 120 dogs and 103 cats. There were 386 ticks and 36 fleas harvested on these dogs, and 141 fleas, 4 ticks, and 2 lice harvested on these cats. Isolation/detection of Bartonella sp. was performed by culture, polymerase chain reaction (PCR), and partial sequencing. Bartonella was isolated from 21 (20.4%) cats and detected by PCR from 20 (19.4%) cats, 2 (1.7%) dogs, 55 (39%) fleas collected from cats, 28 (10%) ticks DNA samples, and 1 (2.8%) flea collected from dogs. When combining culture and PCR data, 27 cats and 55 fleas collected on cats were positive for Bartonella henselae or Bartonella clarridgeiae, but none were coinfected. Approximately half of the B. henselae isolates from 21 cats were B. henselae type I. Moreover, B. henselae, Bartonella phoceensis, Bartonella queenslandensis, Bartonella rattimassiliensis, Bartonella elizabethae DNA was detected in ticks collected from dogs and one flea was B. clarridgeiae PCR positive. This is the first report of such a wide variety of Bartonella spp. detected in Rhipicephalus sanguineus. Further studies are required to understand the relative importance of these ectoparasites to transmit Bartonella spp. in dogs and cats.     

Recent advances in diagnosis and treatment of cat scratch disease

The cause of cat scratch disease (CSD), first described in France in 1950 and in the United States in 1951, was unknown until 1983 when the bacterium in lymph nodes was detected using a Warthin-Starry silver stain. Afipia felis has been an infrequent cause of CSD since1988, when this gram-negative bacterium was first isolated from 10 patients with CSD. In 1992 Bartonella organisms were isolated from immunocompetent and immunocompromised patients. An indirect fluorescent antibody test to detect bartonella-specific serum immunoglobulins was developed in 1992. Since then multiple studies have shown that three Bartonella species may produce either CSD in humans, usually Bartonella henselae or Bartonella clarridgeiae, or bacteremia in healthy cats. Also, these two bacteria and Bartonella quintana cause bacillary angiomatosis, bacillary peliosis, or relapsing bacteremia in humans. Cats are healthy carriers of Bartonella organisms and may be bacteremic for months to years. Cat-to-cat transmission of Bartonella organisms involves the cat flea in absence of direct contact transmission. CSD is the most common cause of regional lymphadenitis in children and adolescents. Present knowledge on the etiology, clinical features, epidemiology, pathogenesis, diagnosis, and management of CSD are presented. Also, brief comments about the etiology, clinical presentation, and treatment of bacillary angiomatosis and bacillary peliosis are provided.     

云南西部地区居民区小型兽类携带病原体检测

目的 了解云南西部地区居民区小型兽类携带病原体情况,为自然疫源性疾病的防治提供科学依据。方法 在滇西地区8个州(市)中抽取的10个县(市、区)40个自然村中,随机抽取800户家庭(每村20户),进行室内捕鼠,采集鼠脾脏标本并提取基因组DNA,鼠肺标本提取RNA,运用聚合酶链反应(PCR)或免疫学方法,检测鼠疫、巴尔通体、伯氏疏螺旋体、巴贝西原虫、人粒细胞无形体、埃立克体、汉坦病毒等病原体。结果 捕获9种421只小型兽类,采集脏器样本404份,血清样本325份。检出鼠疫F1抗体两种方法共同阳性血清1份;扩增到巴尔通体枸橼酸合酶(gltA)基因64份,阳性率为15.84%,基因分析表明属6种基因型;检出伯氏疏螺旋体5S~23S rRNA间隔区基因5份,阳性率为1.24%,系统发育树显示均为Borrelia afzelii型;检出1例复合感染。其余病原体检测均为阴性。结论 滇西地区室内小型兽类感染病原体种类多,分布广,对人类健康有一定的危害,需加强监测并采取预防控制措施。     

Genetic and ecologic characteristics of Bartonella communities in rodents in southern China

Ecologic and bacteriologic observations of small mammals captured in Yunnan Province in the People's Republic of China indicated that Bartonella infections occurred at a high prevalence among some rodent species. Sequence analyses of the citrate synthase genes of these Bartonella demonstrated that rodents in this region harbored a diverse assemblage of strains. The Bartonella isolates obtained from Apodemus, Eothenomys, and Rattus typically clustered separately by genus of rodent host. Cultures obtained from Rattus rats were genetically related to Bartonella elizabethae, a recognized human pathogen. The finding of Bartonella species in a high proportion of the rodent samples from Yunnan suggests the need to investigate whether these agents might be responsible for cases of febrile illnesses of unknown etiology in southern China and elsewhere in southeastern Asia.     

Bartonella strains in small mammals from Dhaka, Bangladesh, related to Bartonella in America and Europe

Ecological and bacteriologic observations of small mammals captured in Dhaka, Bangladesh, indicated that Bartonella infections occurred in high prevalence among lesser bandicoot rats (Bandicota bengalensis), black rats (Rattus rattus), and house shrews (Suncus murinus). Sequence analysis of the citrate synthase gene of Bartonella isolates showed that small mammals in Bangladesh harbored a diverse assemblage of strains. Some cultures were genetically related to Bartonella elizabethae, a species identified from a human patient in the United States. Sequences of some other cultures from Bandicota and Rattus rats were identical to sequences of cultures from domestic rats in France, Portugal, and the United States. The finding of Bartonella species in a high proportion of the mammalian samples from Dhaka suggests the need to study whether these agents might be responsible for human cases of febrile illness of unknown etiology in Bangladesh and elsewhere in south Asia.     

Diseases produced by Bartonella

The genus Bartonella is cause of a broad number of emerging and re-emerging infectious diseases. Clinical manifestations depend on the implicated Bartonella sp. and the immunity of the host. Because there is not a universal therapy for this infection, treatment should be chosen individually. Bartonella sp. is responsible of potentially serious clinical pictures (endocarditis, chronic bacteremia, bacillary angiomatosis, Carrion's disease, etc.), so clinical suspicion, a quick diagnosis and an early treatment provide a better resolution.     

Emerging opportunistic yeast infections

A growing population of immunosuppressed patients has resulted in increasingly frequent diagnoses of invasive fungal infections, including those caused by unusual yeasts. The incidence of non-albicans species of Candida is increasing compared with that of Candida albicans, and several species, such as Candida glabrata and Candida krusei, may be resistant to azole antifungal therapy. Trichosporon species are the second most common cause of fungaemia in patients with haematological malignant disease and are characterised by resistance to amphotericin and echinocandins and poor prognosis. Rhodotorula species belong to the family Cryptococcaceae, and are a cause of catheter-related fungaemia, sepsis, and invasive disease in severely immunosuppressed patients. An increasing number of sporadic cases of invasive fungal infections by non-neoformans cryptococci have been reported in immunocompromised hosts, especially for patients with advanced HIV infection or cancer who are undergoing transplant. Other uncommon yeasts that can cause invasive disease in severely immunosuppressed patients include Geotrichum, Hansenula, Malassezia, and Saccharomyces. Host immune status is a crucial determinant of the type of invasive fungal infection a patient is at risk for. Diagnosis can be challenging and relies heavily on traditional cultures of blood and other sterile sites, although serum (1,3)-β-D-glucan testing might have an adjunctive role. Although rare yeasts are emerging as opportunistic human pathogens, diagnosis remains challenging and treatment suboptimal.     

Bartonella Endocarditis in Complex Congenital Heart Disease

Bartonella species are an important cause of culture-negative endocarditis, with recognized risk factors of alcoholism, homelessness, cat exposure, and pre-existing valvular disease. We report a case of Bartonella henselae endocarditis in a 36-year-old woman with complex congenital heart disease who presented with a 7-month history of hemolytic anemia, leukocytoclastic vasculitis, and recurrent fevers. Transesophageal echocardiogram revealed vegetations on the patient’s native aortic valve and in the right ventricular to pulmonary artery conduit and associated bioprosthetic valve. Diagnosis of B. henselae was confirmed with serum antibody and polymerase chain reaction (PCR) testing and tissue stains. The patient was treated successfully with surgical resection and prolonged antimicrobial therapy with ceftriaxone, gentamicin, and doxycycline. A review of the literature suggests prosthetic valves and complex congenital heart disease are risk factors for Bartonella endocarditis, and a high index of suspicion with antibody and PCR testing can expedite diagnosis and improve outcomes.     

Ecological diversity of Bartonella species infection among dogs and their owner in Virginia

Bartonella species comprise a genus of gram-negative, fastidious, intracellular bacteria that have been implicated in association with an increasing spectrum of disease manifestations in dogs and human patients. In this study, chronic canine and human disease, for which causation was not diagnostically defined, were reported by the breeder of a kennel of Doberman pinschers. In addition to other diagnostic tests, serology, polymerase chain reaction, and enrichment blood culture were used to assess the prevalence of Bartonella sp. infection in the dogs and their owner. From five dogs, Bartonella vinsonii subsp. berkhoffii genotype I, multiple Bartonella henselae strains, and a species most similar to Candidatus B. volans, a rodent-associated Bartonella sp., were amplified and sequenced from biopsy tissues, cerebrospinal fluid, or blood enrichment cultures. The owner was bacteremic with B. vinsonii subsp. berkhoffii genotype I, the same subsp. and genotype detected in one of her dogs. These results further emphasize the ecological complexity of Bartonella sp. transmission in nature.     

Ectoparasitism and vector-borne diseases in 930 homeless people from Marseilles

Homeless people are particularly exposed to ectoparasites, but their exposure to arthropod-borne diseases has not been evaluated systematically. A medical team of 27 persons (7 nurses, 6 infectious disease residents or fellows, 2 dermatologists, and 12 infectious disease specialists) visited the 2 shelters in Marseilles, France, for 4 consecutive years. Homeless volunteers were interviewed, examined, and received care; and blood was sampled for cell counts and detection of bacteremia, antibodies to louse-borne (Rickettsia prowazekii, Bartonella quintana, and Borrelia recurrentis), flea-borne (R. typhi, R. felis), mite-borne (R. akari), and tick-borne (R. conorii) bacterial agents. We selected sex- and age-adjusted controls among healthy blood donors. Over 4 years, 930 homeless people were enrolled. Lice were found in 22% and were associated with hypereosinophilia (odds ratio, 5.7; 95% confidence intervals, 1.46-22.15). Twenty-seven patients (3%) with scabies were treated with ivermectin. Bartonella quintana was isolated from blood culture in 50 patients (5.3%), 36 of whom were treated effectively. The number of bacteremic patient increased from 3.4% to 8.4% (p = 0.02) over the 4 years of the study. We detected a higher seroprevalence to Borrelia recurrentis, R. conorii, and R. prowazekii antibodies in the homeless. Our study shows a high prevalence of louse-borne infections in the homeless and a high degree of exposure to tick-borne diseases and scabies. Despite effective treatment for Bartonella quintana bacteremia and the efforts made to delouse this population, Bartonella quintana remains endemic, and we found hallmarks of epidemic typhus and relapsing fever. The uncontrolled louse infestation of this population should alert the community to the possibility of severe re-emerging louse-borne infections.     

Semi-nested PCR detection of Bartonella henselae in Ixodes persulcatus ticks from Western Siberia, Russia

Questing adult Ixodes persulcatus ticks from Western Siberia, Russia were tested for infections with Bartonella spp. using seminested PCR assay with primers specific to the groEL gene. The proportion of ticks infected with Bartonella spp. was 44% in 2002 (n = 50) and 38% in 2003 (n = 50). Nucleotide sequences of a portion of the PCR products corresponded to Bartonella henselae species.