Seroprevalence of Bartonella henselae in patients awaiting heart transplant in Southern Italy

Seroprevalence of vector-borne pathogens in outdoor workers from southern Italy and associated occupational risk factors

Background

Vector-borne diseases (VBDs) represent an emerging global threat to public health due to the geographical expansion of arthropod vectors. The study aims to assess the seroprevalence of selected vector-borne pathogens (VBPs) in different groups of outdoor workers and the occupational risk factors for exposure to arthropod bites.

Methods

A cross-sectional study was conducted on 170 workers recruited in two different regions of southern Italy, including farmers, forestry workers, veterinarians, geologists/agronomists and administrative employees, and tested for IgG antibodies against Bartonella henselae, Borrelia spp. Coxiella burnetii and Rickettsia conorii, using a chemiluminescent immunoassay (CLIA). The relationship among job characteristics, tick exposure and the prevalence of seropositive subjects for each pathogen was investigated by applying categorical principal component analysis (CATPCA).

Results

A high seroprevalence for C. burnetii (30.0%) and R. conorii (15.3%) was reported, mainly in farmers (67.7% and 54.8%, respectively) and forestry workers (29.0% and 16.1%, respectively), while a low prevalence was observed for B. henselae and Borrelia spp. (8.8% and 4.1%, respectively). The regression equation by CATPCA was significant for C. burnetii and R. conorii (P < 0.001), showing a positive association with job, tick bite exposure, working area and contact with animals.

Conclusions

These findings highlight the need of activating an appropriate occupational health response for minimizing the risk of arthropod vector exposure in workplaces, considering specific preventive measures in particular in high-risk job categories.

Graphical Abstract

Serological and Molecular Detection of Bartonella henselae in Cats and Humans From Egypt: Current Status and Zoonotic Implications

Bartonellosis is a vector-borne zoonotic disease caused by the intracellular bacterium of genus Bartonella. The disease has a worldwide distribution and cats represent the major reservoir of this disease. Despite its global distribution, very limited previous studies have investigated the occurrence of bartonellosis in cats and their owners in Egypt. In an endeavor to explore this topic, we investigated the occurrence of Bartonella henselae (B. henselae) infection in 225 samples (blood, saliva, and claw) obtained from 75 healthy cats in Upper Egypt. These samples were routinely obtained during veterinary clinic visits. This study also involved an examination of 100 humans, including cat owners and people with a history of contact with cats. Attempted isolation and identification of B. henselae in cats were also performed. Furthermore, PCR was performed for molecular identification of B. henselae in blood samples from cats. Meanwhile, an immunofluorescent assay was performed to study the seroprevalence of B. henselae infection in humans. In this study, B. henselae could not be isolated from any of the examined blood, saliva, or claw samples from cats. Interestingly, B. henselae was identified molecularly in 8% (6/75) of blood samples from cats. The seroprevalence of B. henselae in humans was 46% and its occurrence was higher in females (46.6%) than in males (41.7%) (P = 0.748). B. henselae infection was higher among cat owners [51.4% (19/37)] than among people with a history of contact with cats [42.9% (27/63)] (P = 0.410). Infection was higher in rural regions [79.5% (31/39)] than in urban regions [24.6% (15/61)] (P < 0.001). Collectively, this data provide interesting baseline information about the occurrence of B. henselae in cats and humans in Upper Egypt, which reflects the potential zoonotic transmission of this bacterium. Future study is mandatory to explore the occurrence of B. henselae in major reservoirs in Egypt.

Bartonella infections diagnosed in the French reference center, 2014-2019, and focus on infections in the immunocompromised

We studied retrospectively 651 PCR-confirmed Bartonella infections diagnosed at the French reference center for bartonellosis from 2014 to 2019. The most common form was cat-scratch disease (89%) followed by endocarditis (9%). Disseminated forms (2%) mainly presented as bacillary angiomatosis or peliosis hepatis in solid organ transplant recipients.

The seroprevalence of Bartonella spp. in the blood of patients with musculoskeletal complaints and blood donors, Poland: a pilot study

BACKGROUND

Bartonella spp. can cause a variety of diseases, such as lymphadenopathies, cat scratch disease, and trench fever, but can also give rise to many non-specific symptoms. No data exists regarding the prevalence of Bartonella spp. in patients with musculoskeletal complaints, nor among blood donors in Poland.

METHODS

The presence of anti-Bartonella IgM and IgG in the serum of blood donors (n = 65) (Lodz, Poland) and in the patients of the Department of Rheumatology Clinic (n = 40) suffering from musculoskeletal symptoms was tested by immunofluorescence. Blood samples were cultured on enriched media. Epidemiological questionnaires were used to identify key potential risk factors, such as sex, age, contact with companion animals, and bites from insects or animals.

RESULTS

Altogether, 27 of the 105 tested subjects were seropositive for Bartonella henselae IgG (23%) and three for Bartonella quintana IgG (2.85%); IgMs against B. henselae were found in three individuals (2.85%), and IgMs against B. quintana were found in one (1.54%). No statistically significant difference was found between the prevalence of B. henselae in the blood of donors or patients and the presence of unexplained musculoskeletal complaints (23% vs 30%). Individuals who had kept or been scratched by cats were not more likely to be B. henselae seropositive (p > 0.01). Tick bites were more commonly reported in patients, but insignificantly (p > 0.01).

CONCLUSION

This is the first report of a high seroprevalence of anti-Bartonella IgG in patients with musculoskeletal symptoms and in blood donors in Poland. The obtained results indicate that such seroprevalence may have a possible significance in the development of musculoskeletal symptoms, although it should be confirmed on a larger group of patients. Asymptomatic bacteremia might occur and pose a threat to recipients of blood from infected donors. Hence, there is a need for more detailed research, including molecular biology methods, to clarify the potential risk of Bartonella spp. being spread to immunocompromised individuals.

KEY POINTS

• This is the first study presenting high seroprevalence of Bartonella spp. in Poland. • IgG and IgM antibodies against B. quintana were found in blood samples of blood donors.

Serological and molecular detection of Bartonella henselae in specimens from patients with suspected cat scratch disease in Italy: A comparative study

Cat scratch disease (CSD) is an infectious disease caused by Bartonella henselae, usually characterized by self-limiting regional lymphadenopathy and fever. Given the low clinical diagnostic sensitivity and specificity of conventional anti-B. henselae indirect immunofluorescence assays (IFAs), real-time polymerase chain reaction (PCR)-based detection of B. henselae is now being proposed as a more sensitive tool to diagnose CSD. Thus, here we have assessed the efficacy of real-time PCR in detecting B. henselae in different specimens from patients with suspected CSD and compared it to that of IFA. From March 2011 to May 2016, at the Microbiology and Virology Unit, Azienda Ospedaliera Universitaria Città della Salute e della Scienza di Torino, Turin, Italy, 115 clinical specimens (56 aspirated pus, 39 fresh lymph node biopsies, and 20 whole blood samples) and 99 sera from 115 patients with suspected CSD (62 females and 53 males between the ages of 3 months and 68 years) were analyzed by both real-time PCR, used in a qualitative way, and IFA (IgM and IgG) for the presence of B. henselae. For 16 patients, serological results were not available due to a clinical decision not to request the test. B. henselae DNA positivity was detected by real-time PCR in 37.39% of patients, while 62.61% of them were negative. Thus, patients were divided into two groups: real-time PCR+ (n = 43) and real-time PCR- (n = 72). Real-time PCR screening of whole blood, biopsies, and aspirated pus revealed B. henselae positivity in 40%, 38.46%, and 35.71% of patients, respectively. When we analyzed samples by IFA, we found the presence of B. henselae in 28 out of 99 (28.28%) patients, of which 11 (11.11%) belonged to the real-time PCR+ group and 17 (17.17%) to the real-time PCR- group. Among the 71 seronegative subjects, 16 (16.16%) were found positive for B. henselae by real-time PCR. Thus, by combining the results of both assays, we were able to increase the percentage of B. henselae positive specimens from 27.27% (real-time PCR) or 28.28% (IFA) to 44.44% (real-time PCR+IFA). Altogether, these findings indicate that the early detection of B. henselae in patients with suspicious CSD through combined real-time PCR and serological analyses can lead to a more accurate diagnosis of CSD, thereby allowing prompt and appropriate disease management.

Effectiveness of a 10% imidacloprid/4.5% flumethrin polymer matrix collar in reducing the risk of Bartonella spp. infection in privately owned cats

BACKGROUND

Bartonella henselae, Bartonella clarridgeiae and the rare Bartonella koehlerae are zoonotic pathogens, with cats being regarded as the main reservoir hosts. The spread of the infection among cats occurs mainly via fleas and specific preventive measures need to be implemented. The effectiveness of a 10% imidacloprid/4.5% flumethrin polymer matrix collar (Seresto®, Bayer Animal Health), registered to prevent flea and tick infestations, in reducing the risk of Bartonella spp. infection in privately owned cats, was assessed in a prospective longitudinal study.

METHODS

In March-May 2015 [Day 0 (D0)], 204 privately-owned cats from the Aeolian Islands (Sicily) were collared (G1, n = 104) or left as controls (G2, n = 100). The bacteraemia of Bartonella spp. was assessed at enrolment (D0) and study closure (D360) by PCR and DNA sequencing both prior to and after an enrichment step, using Bartonella alpha proteobacteria growth medium (BAPGM).

RESULTS

A total of 152 cats completed the study with 3 in G1 and 10 in G2 being positive for Bartonella spp. Bartonella henselae genotype I ZF1 (1.35%) and genotype II Fizz/Cal-1 (6.76%) as well as B. clarridgeiae (5.41%) were detected in cats of G2. Bartonella clarridgeiae was the only species detected in G1. Based on the yearly crude incidence of Bartonella spp. infection (i.e. 3.85% in G1 and 13.51% in G2; P = 0.03) the Seresto® collar achieved a preventative efficacy of 71.54%. The incidence of Bartonella spp. infection was more frequent in flea-infested cats (6/33, 18.18%) than in uninfested ones (7/112, 5.88%) (P = 0.036).

CONCLUSIONS

Cats living in the Aeolian Islands are exposed to B. henselae and B. clarridgeiae. The Seresto® collar provided significant risk reduction against Bartonella spp. infection in outdoor cats under field conditions. Such a preventative tool could be a key contribution for decreasing the risk of Bartonella spp. infection in cats and thus ultimately to humans.

Prevalence of Bartonella spp. by culture, PCR and serology, in veterinary personnel from Spain

Background

The genus Bartonella includes fastidious, facultative intracellular bacteria mainly transmitted by arthropods and distributed among mammalian reservoirs. Bartonella spp. implicated as etiological agents of zoonoses are increasing. Apart from the classical Bartonella henselae, B. bacilliformis or B. quintana, other species (B. elizabethae, B. rochalimae, B. vinsonii arupensis and B. v. berkhoffii, B. tamiae or B. koehlerae, among others) have also been associated with human and/or animal diseases. Laboratory techniques for diagnosis (culture, PCR assays and serology) usually show lack of sensitivity. Since 2005, a method based on a liquid enrichment Bartonella alphaproteobacteria growth medium (BAPGM) followed by PCRs for the amplification of Bartonella spp. has been developed. We aimed to assess culture, molecular and serological prevalence of Bartonella infections in companion animal veterinary personnel from Spain.

Methods

Each of 89 participants completed a questionnaire. Immunofluorescence assays (IFA) using B. vinsonii berkhoffii (genotypes I, II and III), B. henselae, B. quintana and B. koehlerae as antigens were performed. A cut-off of 1:64 was selected as a seroreactivity titer. Blood samples were inoculated into BAPGM and subcultured onto blood agar plates. Bartonella spp. was detected using conventional and quantitative real-time PCR assays and DNA sequencing.

Results

Among antigens corresponding to six Bartonella spp. or genotypes, the lowest seroreactivity was found against B. quintana (11.2%) and the highest, against B. v. berkhoffii genotype III (56%). A total of 27% of 89 individuals were not seroreactive to any test antigen. Bartonella spp. IFA seroreactivity was not associated with any clinical sign or symptom. DNA from Bartonella spp., including B. henselae (n = 2), B. v. berkhoffii genotypes I (n = 1) and III (n = 2), and B. quintana (n = 2) was detected in 7/89 veterinary personnel. PCR and DNA sequencing findings were not associated with clinical signs or symptoms. No co-infections were observed. One of the two B. henselae PCR-positive individuals was IFA seronegative to all tested antigens whereas the other one was not B. henselae seroreactive. The remaining PCR-positive individuals were seroreactive to multiple Bartonella spp. antigens.

Conclusions

High serological and molecular prevalences of exposure to, or infection with, Bartonella spp. were found in companion animal veterinary personnel from Spain. More studies using BAPGM enrichment blood culture and PCR are needed to clarify the finding of Bartonella PCR-positive individuals lacking clinical symptoms.

Electronic supplementary material

The online version of this article (10.1186/s13071-017-2483-z) contains supplementary material, which is available to authorized users.

Seronegative disseminated Bartonella spp. infection in an immunocompromised patient

An 11 year old, hispanic girl with a history of B-cell acute lymphoblastic leukemia was admitted to the hospital for symptoms compatible with Bartonella henselae infection. The first molecularly diagnosed case of disseminated Bartonella henselae infection was reported in an immunocompromised patient in Lima, Peru. The analysis was confirmed by Polymerase Chain Reaction and automated sequencing of a liver biopsy sample, even though the serologic tests were negative. In conclusion, Bartonella spp. infection should have a particular diagnostic consideration in immunocompromised patients with fever of unknown origin and further investigation regarding the patient's past exposures with cats should also be elicited.

Infections and cardiovascular disease: is Bartonella henselae contributing to this matter?

Cardiovascular disease is still the major cause of death worldwide despite the remarkable progress in its prevention and treatment. Endothelial progenitor cells (EPCs) have recently emerged as key players of vascular repair and regenerative medicine applied to cardiovascular disease. A large amount of effort has been put into discovering the factors that could aid or impair the number and function of EPCs, and also into characterizing these cells at the molecular level in order to facilitate their therapeutic applications in vascular disease. Interestingly, the major cardiovascular risk factors have been associated with reduced number and function of EPCs. The bacterial contribution to cardiovascular disease represents a long-standing controversy. The discovery that Bartonella henselae can infect and damage EPCs revitalizes the enduring debate about the microbiological contribution to atherosclerosis, thus allowing the hypothesis that this infection could impair the cardiovascular regenerative potential and increase the risk for cardiovascular disease. In this review, we summarize the rationale suggesting that Bartonella henselae could favour atherogenesis by infecting and damaging EPCs, thus reducing their vascular repair potential. These mechanisms suggest a novel link between communicable and non-communicable human diseases, and put forward the possibility that Bartonella henselae could enhance the susceptibility and worsen the prognosis in cardiovascular disease.