Dirofilaria repens is a parasite of animals and humans, transferred by mosquitoes. The assessment of the presence of D. repens-infected vertebrate hosts in the investigated area can be performed by xenomonitoring—detection of the parasite in blood-feeding arthropods. Our study aimed to evaluate PCR xenomonitoring of mosquitoes as a tool for dirofilariosis surveillance in Poland. We were also interested whether inter-study comparisons at the international level would be possible. Mosquitoes were collected in a single locality in Mazowsze province in Poland, in which between 12 and 20% of dogs were infected with D. repens and autochthonous human dirofilariosis was confirmed. All captured female mosquitoes were divided into pools; alternatively, single mosquitoes were analyzed; DNA was isolated and subjected to PCR and real-time PCR for detection of D. repens. The estimations of infection rates of mosquitoes with D. repens, based on PCR results, varied from 0 to 1.57% even between assays for detection of distinct fragments of the same marker—cytochrome oxidase subunit one gene. Polymorphisms of the DNA sequence within binding sites of the primers used in D. repens xenomonitoring assays, applied in European studies, were identified. Non-specific amplification of Setaria tundra (Nematoda: Onchocercidae) DNA occurred. Surveillance of dirofilariosis by PCR mosquito xenomonitoring is possible; however, the efficiency of the approach on territories where the prevalence of the disease among definitive hosts is lower than 12% remains unknown. Furthermore, mosquito infection rate estimations can be PCR assay dependent, which makes inter-study comparisons difficult. The results obtained in independent European xenomonitoring studies were contradictory. International collaboration would be required to establish a standardized set of assays for sensitive and specific xenomonitoring-based dirofilariosis surveillance.

Hepatitis E virus (HEV) is known as zoonotic agent. The main reservoirs of HEV in Europe are pigs, wild boars, and deer. Hunting activity is considered to be a risk factor for HEV infection. We conducted a cross-sectional study among 1021 Polish hunters. To understand socio-demographic characteristics of this population and to gather information on potential exposures, all participants completed a questionnaire. Commercial immunoassays were employed to estimate seroprevalence anti-HEV. Samples with confirmed positive result of anti-HEV IgM were examined for HEV RNA. Anti-HEV IgG were identified in 227 people, 22.2% of the studied group. Seroprevalence among the studied hunters was associated with age ≥65 [adjusted prevalence ratio (aPR) 1.6, p = 0.037), living in a house (aPR 1.54, p = 0.013), professional contact with farm animals (aPR 1.09, p = 0.01), and consumption of stewed offal (aPR 1.61, p = 0.00). Washing hands after disembowelment was linked to lower seroprevalence (aPR 0.53; p = 0.00). Lower prevalence of anti-HEV IgG among hunters living in cities was associated with age: 35–49 (aPR 0.52, p = 0.011) and 50–64 (aPR 0.93, p = 0.58), living in a house (aPR 1.58, p = 0.002) and owning a cat (aPR 0.58, p = 0.042). Among hunters living in rural areas, seropositivity was associated with contact with farm animals (aPR 1.66, p = 0.013) and consumption of stewed offal (aPR 1.81; p = 0.001). Contrary to initial assumptions, it was concluded that hunting was of significantly lesser importance than other factors. Due to the high level of HEV seroprevalence identified, we recommend conducting a large-scale study in the general population of Poland.

The goal of the study was to design a single tube PCR test for detection and differentiation of Babesia species in DNA samples obtained from diverse biological materials. A multiplex, single tube PCR test was designed for amplification of approximately 400 bp region of the Babesia 18S rRNA gene. Universal primers were designed to match DNA of multiple Babesia spp. and to have low levels of similarity to DNA sequences of other intracellular protozoa and Babesia hosts. The PCR products amplified from Babesia DNA isolated from human, dog, rodent, deer, and tick samples were subjected to high-resolution melting analysis for Babesia species identification. The designed test allowed detection and differentiation of four Babesia species, three zoonotic (B. microti, B. divergens, B. venatorum) and one that is generally not considered zoonotic—Babesia canis. Both detection and identification of all four species were possible based on the HRM curves of the PCR products in samples obtained from the following: humans, dogs, rodents, and ticks. No cross-reactivity with DNA of Babesia hosts or Plasmodium falciparum and Toxoplasma gondii was observed. The lack of cross-reactivity with P. falciparum DNA might allow using the assay in endemic malaria areas. The designed assay is the first PCR-based test for detection and differentiation of several Babesia spp. of medical and veterinary importance, in a single tube reaction. The results of the study show that the designed assay for Babesia detection and identification could be a practical and inexpensive tool for diagnostics and screening studies of diverse biological materials.Electronic supplementary materialThe online version of this article (doi:10.1007/s00436-017-5576-x) contains supplementary material, which is available to authorized users.

Background Clinical manifestations in infection caused by B. miyamotoi can mimick highly variable symptoms of Lyme disease. The aim of our studies was to detect DNA of B. miyamotoi spirochetes in clinical materials from patients suspected of neuroborreliosis(retrospectively).Methods Samples of blood serum and cerebrospinal fluid were collected from 133 patients with clinical manifestations of neuroborreliosis. Diagnosis was established by detection of IgM and / or IgG specific antibodies to B. burgdorferi with ELISA in both sera and CSF. Specificity of positive ELISA results in sera were confirmed with Western-blot test. Bacterial DNA from the collected material was extracted, amplified and sequenced.Results Among 133 patients with clinical manifestations of neuroborreliosis recognized in the years 2010-2018., DNA of B. miyamotoi was detected in CSF from 1 (0.8%) patient with extraocular optic neuritis of the left eye (GenBank accession No. MK674170 and MK674171).Conclusion Detection of B. miyamotoi in patients with central nervous system infections, will allow a better understanding of the epidemiology of infections caused by Borrelia sp. spirochetes. Patients with neurological symptoms and questionable serological findings are a serious diagnostic problem, due to failure to meet the criteria for neuroboreliosis. This indicates the need for further studies of patients with signs of CNS infection.

In recent years, numerous studies screening mosquitoes for filarioid helminths (xenomonitoring) have been performed in Europe. The entomological monitoring of filarial nematode infections in mosquitoes by molecular xenomonitoring might serve as the measure of the rate at which humans and animals expose mosquitoes to microfilariae and the rate at which animals and humans are exposed to the bites of the infected mosquitoes. We hypothesized that combining the data obtained from molecular xenomonitoring and phenological studies of mosquitoes in the urban environment would provide insights into the transmission risk of filarial diseases. In our search for Dirofilaria spp.-infected mosquitoes, we have found Setaria tundra-infected ones instead, as in many other European studies. We have observed that cross-reactivity in PCR assays for Dirofilaria repens, Dirofilaria immitis, and S. tundra COI gene detection was the rule rather than the exception. S. tundra infections were mainly found in Aedes mosquitoes. The differences in the diurnal rhythm of Aedes and Culex mosquitoes did not seem a likely explanation for the lack of S. tundra infections in Culex mosquitoes. The similarity of S. tundra COI gene sequences found in Aedes vexans and Aedes caspius mosquitoes and in roe deer in many European studies, supported by data on Ae. vexans biology, suggested host preference as the most likely cause of the mosquito genus-biased infections. High diversity of the COI gene sequences isolated in the city of Wroclaw in south western Poland and the presence of identical or almost identical sequences in mosquitoes and roe deer across Europe suggests that S. tundra has been established in most of Europe for a very long time.