Prevalence of Borrelia, Neoehrlichia mikurensis and Babesia in ticks collected from vegetation in eastern Poland.

In Poland, tick-borne diseases constitute the majority of diseases related to exposure to biological agents with a predominance of Lyme borreliosis; therefore, research on ticks as a reservoir of various pathogens remains crucial in the epidemiology of human diseases after tick bites. This study aimed to identify the occurrence of Borrelia burgdorferi sensu lato, Borrelia miyamotoi, Neoehrlichia mikurensis, and Babesia spp. in ticks collected from vegetation in eastern Poland. Additionally, the prevalence of co-infections in the adult Ixodes ricinus ticks was determined. Among I. ricinus ticks the predominantly detected pathogen was B. burgdorferi s.l. (23%) with B. burgdorferi sensu stricto as the most frequently identified species, followed by B. garinii. In 2013, the double or triple infections of B. burgdorferi s.s., B. afzelii, and B. garinii species did not exceed 9% in adult ticks, whereas in 2016, the prevalence of mixed infections reached 29%. The prevalence of N. mikurensis and B. miyamotoi in I. ricinus was determined at the same level of 2.8%. Four Babesia species were identified in the examined I. ricinus population: B. microti (1.5%), B. venatorum (1.2%), B. divergens (0.2%), and B. capreoli (0.1%). Co-infections were detected in 10.1% of all infected ticks with the highest prevalence of co-infections with B. burgdorferi s.l. and Babesia species. The changes in the prevalence and the distribution of particular pathogens within tick populations indicate the need for monitoring the current situation related to tick-borne pathogens from the aspect of risk to human health.

Timber-colonizing gram-negative bacteria as potential causative agents of respiratory diseases in woodworkers.

OCCURRENCE: Gram-negative bacteria occur commonly in the inner tissues of stored coniferous and deciduous timber, showing a marked variation in numbers. The greatest maximal numbers are found in the sapwood of coniferous timber. The common constituents of the Gram-negative biota are potentially pathogenic species of Enterobacteriaceae family of the genera Rahnella, Pantoea, Enterobacter, and Klebsiella. The air of wood-processing facilities is polluted with the wood-borne Gram-negative bacteria and produced by them endotoxin, as demonstrated worldwide by numerous studies. EFFECTS: There are three potential pathways of the pathogenic impact of wood-borne Gram-negative bacteria on exposed woodworkers: allergic, immunotoxic, and infectious. Allergic impact has been underestimated for a long time with relation to Gram-negative bacteria. Hopefully, the recent demonstration of the first documented case of hypersensitivity pneumonitis (HP) in woodworkers caused by Pantoea agglomerans which developed in extremely large quantities in birch sapwood, would speed up finding of new wood-related cases of HP caused by Gram-negative bacteria. The second pathway is associated with endotoxin, exerting strong immunotoxic (excessively immunostimulative) action. It has been demonstrated that endotoxin is released into wood dust in the form of nano-sized microvesicles, by peeling off the outer membrane of bacteria. Endotoxin microvesicles are easily inhaled by humans together with dust because of small dimensions and aerodynamic shape. Afterwards, they cause a nonspecific activation of lung macrophages, which release numerous inflammatory mediators causing an inflammatory lung reaction, chest tightness, fever, gas exchange disorders, and bronchospasm, without radiographic changes. The resulting disease is known as "Organic Dust Toxic Syndrome" or "toxic pneumonitis." The potential third pathway of pathogenic impact is infection. The suspected species is Klebsiella pneumoniae that may occur commonly in wood dust; however, until now this pathway has not been confirmed. CONCLUSION: Summarizing, Gram-negative bacteria-inhabiting timber should be considered, besides filamentous fungi and actinobacteria, as important risk factors of occupational disease in woodworkers that could be either HP with allergenic background or toxic pneumonitis elicited by endotoxin.

Detection of Legionella spp. and occurrence of virulence genes: lvh, rtxA and enhC in water samples from artificial water systems.

INTRODUCTION AND OBJECTIVE: Legionella spp. are ubiquitous worldwide in natural water sources (rivers, lakes) as well as in man-made water systems (cooling towers, tap water, spas). The most common species causing the disease in humans is Legionella pneumophila. Pathogenicity of Legionella is related to the genes associated with virulence. The study aimed to detect Legionella spp. DNA in man-made water systems, and to examine the presence of selected virulence genes (lvh, rtxA, enhC) in Legionella-positive samples. MATERIAL AND METHODS: A total of 52 water samples from hot and cold water systems collected from urban and rural areas were investigated for the presence of Legionella by polymerase chain reaction (PCR). The detection of three virulence loci (lvh, rtxA, and enhC) in water samples was investigated using PCR. RESULTS: Legionella spp. was detected in over half the tested samples (55.77%), both in water from hot (55.88%) and cold (55.56%) water systems. Sequencing confirmed the presence of Legionella pneumophila in the tested samples. Among all Legionella-positive isolates, at least one virulence gene was detected in the case of 55.17% (16/29) of environmental samples. The lvh locus was most frequently present in all specimens. CONCLUSIONS: The presence of Legionella pneumophila, the causative agent of Legionnaires' disease, in hot and cold water systems from rural and urban localities, indicates a risk to public health. The occurrence of virulence genes in tested samples suggests that L. pneumophila has the potential to cause human disease.

Potential sources of infection with selected zoonotic agents in the veterinary work environment - pilot studies.

INTRODUCTION AND OBJECTIVE: The problem of occupational biohazards is very important, especially in the field of agriculture and in human and veterinary medicine. The aim of the study was to determine the potential sources of infection in veterinary professionals with selected zoonotic agents, including: Toxoplasma gondii, Giardia duodenalis, Leptospira spp., Cryptosporidium spp. and Coxiella burnetii. MATERIAL AND METHODS: A total of 50 air samples from barns, piggeries and veterinary surgeries were examined for the presence of Leptospira spp. and C. burnetii DNA. Serum samples of 86 pigs and 80 cows were tested for the presence of antibodies to Leptospira spp. and to phase I and II C. burnetii antigens. Serum of 70 cats were tested for the presence of antibodies to T. gondii and 65 samples of cat faeces for the presence of T. gondii oocysts. The presence of G. duodenalis and Cryptosporidium spp. were examined in 50 of dog faeces and 50 of bovine faeces samples. RESULTS: DNA of Leptospira spp. was detected in 2 air samples from the piggeries (4%). C. burnetii DNA was not found in any sample. Anti-Leptospira spp. antibodies were detected in 51 (59.3%) of examined pigs. Neither anti-Leptospira spp. nor anti-C. burnetii antibodies were found among samples of bovine serum. Anti-T. gondii antibodies was found in 52 cat serum samples (74.3%). Among samples of cat faeces, no T. gondii oocysts were detected. In one sample of cattle stool (2%), G. duodenalis was detected and in another (2%) - Cryptosporidium spp. G. duodenalis was detected in 7 samples (14%) and Cryptosporidium spp. in 2 samples (2%) of dog faeces. CONCLUSIONS: The results of this study demonstrate the potential risk of infection with Leptospira spp. in veterinarians working with pigs. Veterinarians could be also be at risk of infection with T. gondii and G. duodenalis.

Study on Toxoplasma Gondii, Leptospira Spp., Coxiella Burnetii, and Echinococcus Granulosus Infection in Veterinarians from Poland.

INTRODUCTION: Exposure to zoonotic factors in veterinary practice is closely related to the nature of the work. The main aim of the study was to determine the risk of selected zoonotic infections among the occupational group of veterinarians in Poland. MATERIAL AND METHODS: Blood samples of 373 veterinarians (162 males and 211 females) from 12 provinces of Poland were collected by the venipuncture of a forearm for serological tests. Commercial immunoenzymatic tests (ELISA) were used for detection of specific IgG antibodies to Echinococcus granulosus, IgM and IgG to Leptospira spp., and IgM, IgA, and I and II phase IgG to Coxiella burnetii. Enzyme-linked fluorescence assays (ELFA) were used to detect IgM and IgG antibodies to Toxoplasma gondii. RESULTS: Positive results were found in 209 (56.0%) veterinarians for at least one of the examined diseases. The overall proportion of participants found to have specific Toxoplasma gondii antibodies in the IgM and/or IgG assays amounted to 44.5%. The presence of Coxiella burnetii antibodies was found in 16 (4.3%) subjects, while Leptospira spp. antibodies were detected in 63 (16.9%) veterinarians. Among the 373 veterinarians examined, no Echinococcus granulosus antibodies were found. CONCLUSION: Results of the study seem to indicate a slightly elevated risk of Toxoplasma gondii infection and a moderate risk of infection with Leptospira spp. and Coxiella burnetii in veterinarians.