Occurrence and Abundance of Dermacentor reticulatus in the Habitats of the Ecological Corridor of the Wieprz River, Eastern Poland

Ecological corridors are zones of natural vegetation, which connect with other vegetation strips to create migration routes for animals and plants. The aim of our study was to investigate the occurrence and relative abundance of Dermacentor reticulatus in various habitats of the ecological corridor of the Wieprz River in eastern Poland. Ticks were collected using the flagging method in seven sites within the ecological corridor of the Wieprz River, i.e., one of the longest uninterrupted vegetation strips in eastern Poland. The presence of D. reticulatus adults was confirmed in each of the examined sites. The autumn peak of tick activity dominated in most plots. During this period, on average up to 309.7 individuals were collected within 30-min. The results of our study show that, due to the high abundance of local D. reticulatus populations, the habitats located in the ecological corridor of the Wieprz River can be regarded as preferred habitats of this tick species.

A Case of Anaplasmosis during a Warm Minnesota Fall

A healthy 33 year old male presented in December with a 3 week history of fever and fatigue. He had been deer-hunting in northern Minnesota 1 month prior and had sustained a tick bite. Extensive laboratory investigations and a lumbar puncture were conducted. He was empirically with doxycycline and had rapid improvement in his symptoms. Subsequently, PCR and serologic testing returned positive for Anaplasma phagocytophlium. Anaplasmosis is a tick-borne illness caused by the bacterium Anaplasma phagocytophilum and is typically seen in the warmer months. This patient’s presentation in December was uncommon for a tick-borne illness in Minnesota. Regional weather records demonstrated unseasonably warm temperatures during the patient’s trip. Ixodes ticks are known to be sensitive to temperature and humidity, which likely contributed to increased tick activity, leading to disease transmission. This case highlights the importance for clinicians to be aware of local weather patterns and how this might influence seasonal disease presentations.

The role of host phenology for parasite transmission

Phenology is a fundamental determinant of species distributions, abundances, and interactions. In host–parasite interactions, host phenology can affect parasite fitness due to the temporal constraints it imposes on host contact rates. However, it remains unclear how parasite transmission is shaped by the wide range of phenological patterns observed in nature. We develop a mathematical model of the Lyme disease system to study the consequences of differential tick developmental-stage phenology for the transmission of B. burgdorferi. Incorporating seasonal tick activity can increase B. burgdorferi fitness compared to continuous tick activity but can also prevent transmission completely. B. burgdorferi fitness is greatest when the activity period of the infectious nymphal stage slightly precedes the larval activity period. Surprisingly, B. burgdorferi is eradicated if the larval activity period begins long after the end of nymphal activity due to a feedback with mouse population dynamics. These results highlight the importance of phenology, a common driver of species interactions, for the fitness of a parasite.

Ixodid ticks in the Western Ukraine

During the 2018–2019 years, 2884 ticks were collected from five species of animals, including pets (dogs and cats), cattle (cows and horses) and wildlife (wild boar) in Khmelnytsky, Chernivtsi and Vinnytsia regions. Ixodid ticks were identified as: D. reticulatus (2370; 82.2 % of all collected ticks), I. ricinus 510 (17.7 %) and 4 of I. hexagonus (0.1 %) from cats. Adult D. reticulatus (77 %) and I. ricinus (23 %) were detected in dogs. Ixodid ticks collected from horses were D. reticulatus (95 %) and I. ricinus (5 %), and from cows – D. reticulatus (93 %) and I. ricinus (7 %). I. ricinus was the predominant tick collected from cats (58 %). 100 % of D. reticulatus was collected from wild boars. Most ticks were collected during the spring tick activity between March and May. However, D. reticulatus was found on animals every month, including the winter. D. reticulatus males accounted for the overwhelming majority of ticks collected in winter (68 % for dogs, 84 % for wild boars). In all other seasons D. reticulatus females prevailed – 66 % in dogs, 77 % in horses and 71 % in cattle, in all areas. In addition, 4 females of I. hexagonus were removed from the cat in June. The average number of ticks per animal was about three ticks among dogs, two in cats, fourteen in cattle, seven in horses and seven in wild boars. Particularly high amount of D. reticulatus was recorded on cattle and horses in the spring. The relatively high amount of I. ricinus was observed in cats in the spring months. To evaluate the natural biocenoses of the three ticks species in the study areas, the ticks were collected using a flag in urban parks and rural areas. Two types of ticks were found in open areas. The density of adult D. reticulatus ticks in the open areas was relatively high, above 20 mites/1000 m2 in most places. The density of adult ticks of I. ricinus was significantly lower in the typical habitat (forests), within 3 mites/1000 m2, several times lower than the density of D. reticulatus in the typical habitat. Thus, in the western regions of Ukraine, two species of I. ricinus and D. reticulatus mites are widespread in natural biocenoses, as well as in farm and domestic animals, D. reticulatus is the dominant species. This type of tick is active throughout the year, so constant preventive treatment of animals is required to prevent infection with tick-borne diseases.

Monitoring Dermacentor reticulatus Host-Seeking Activity in Natural Conditions

Ticks are hematophagous ectoparasites of humans and animals. These arthropods employ different strategies in their host-seeking activity; most often, it is the “nest”- and “pasture-questing” behaviour. Some species, e.g., Dermacentor reticulatus, exhibit both types of activity depending on their developmental stage. The aim of the present study was to investigate the host-seeking activity of adult D. reticulatus ticks in the eastern part of Poland. To this end, ticks were collected with the flagging method during their seasonal activity in three different types of habitat. Active specimens were marked with a permanent marker and then released. This was repeated consistently at 7-day intervals using a different colour of the marker each time, which allowed tracking the questing activity of the specimens. Most frequently, repetitive tick activity (repeated up to seven times) was noted in a locality surrounded by urban developments. In an agriculturally unused open meadow habitat, 69.9% of D. reticulatus ticks were found to undertake questing activity only once. D. reticulatus females proved to be more aggressive and determined to find a host than the males of this species. Adult D. reticulatus ticks are able to stay in the habitat for a long time and undertake multiple host-seeking activities. The greatest threat of attacks on animals, including domestic animals, and sporadically humans, by these ticks occurs in meadow habitats, which are preferred by this species.

Management Options for Ixodes ricinus-Associated Pathogens: A Review of Prevention Strategies

Ticks are important human and animal parasites and vectors of many infectious disease agents. Control of tick activity is an effective tool to reduce the risk of contracting tick-transmitted diseases. The castor bean tick (Ixodes ricinus) is the most common tick species in Europe. It is also a vector of the causative agents of Lyme borreliosis and tick-borne encephalitis, which are two of the most important arthropod-borne diseases in Europe. In recent years, increases in tick activity and incidence of tick-borne diseases have been observed in many European countries. These increases are linked to many ecological and anthropogenic factors such as landscape management, climate change, animal migration, and increased popularity of outdoor activities or changes in land usage. Tick activity is driven by many biotic and abiotic factors, some of which can be effectively managed to decrease risk of tick bites. In the USA, recommendations for landscape management, tick host control, and tick chemical control are well-defined for the applied purpose of reducing tick presence on private property. In Europe, where fewer studies have assessed tick management strategies, the similarity in ecological factors influencing vector presence suggests that approaches that work in USA may also be applicable. In this article we review key factors driving the tick exposure risk in Europe to select those most conducive to management for decreased tick-associated risk.

Integrated system of approach for the control of ixodid ticks in the western region of Ukraine

For the control of ixodid ticks it is necessary to develop an integrated system of approach that provide a scientific and practical component. The integrated method is the most effective way to control arthropods. The research was conducted during 2018-2020 in the western region of Ukraine (Khmelnytsky, Chernivtsi, Vinnytsia regions). Based on data obtained in previous studies, as well as on the study of factors such as ticks species (Ixodes ricinus, Dermacentor reticulatus), environmental conditions and the possibility of certain measures in this region, an integrated system of measures to regulate the number of ixodid ticks in Western Ukraine were developed. In each region, two experimental private farms and one control farm were selected; the territory of the farms was about 20,000 m2. During the entire study period, 379 D. reticulatus ticks and 165 I. ricinus ticks were collected in all areas. In 2019, farms that were located at a distance of 1-1.5 km from swamps, lowlands and shrubs in open, dry, sunny areas showed the lowest frequency of ticks on animals. So, in May 2019, on average, in experimental farms on dogs, 9, 7 and 11 ticks were found on one animal in the Khmelnytsky, Chernivtsi and Vinnitsa regions, respectively. During acarological examination of farms in the Khmelnytsky region, the average density of ticks was 8, in Chernivtsi - 5, in Vinnitsa - 7 ticks / 1000 m2 in the spring peak of tick activity. In addition, taking into account the seasonal dynamics of ticks activity during 2018, mechanical cleaning of the territory and acaricidal treatments of vegetation were carried out from autumn 2019 to autumn 2020 - in spring (March, May) and autumn (September). According to the results of our research, the use of acaricidal treatments provided a decrease in the number of ticks populations by 50-90 % within 6-8 weeks. When collecting ticks for the flag in experimental plots of the Khmelnytsky region in 2020, the average density of ticks was 4, Chernivtsi - 2, Vinnitsa - 1 tick / 1000 m2 in the spring peak of tick activity. We also found that during the complex acaricidal treatment of the territory and the use of drops or sprays based on fipronil in 2020, half as many ticks were found on dogs than in 2019, which averaged 4 ticks in the Khmelnytsky region, in Chernivtsi - 3 and 5 ticks in the Vinnytsia region. In addition, it was found that mechanical cleaning of the area also helped to reduce the attractiveness of the area for small mammals.

Epidemiological features of Ixodic tick-borne Borreliosis in children in the Ulyanovsk region

This paper presents materials on the incidence of children with ixodiс tick-borne borreliosis in the Ulyanovsk region for the period 1996—2017.28 cases of tick-borne borreliosis among children were recorded. Tick suction in April-May was observed in 6 (21.4%) children, in June—August — in 12 (42.9%), in September—November — in 10 (35.7%). Migratory erythema was detected in 15 patients (53.6%). In half of the cases, moderate intoxication symptoms were observed (57.1%). Borreliosis was confirmed laboratory early in 75% of cases.Thus, a feature of ixodiс tick-borne borreliosis in children in the Ulyanovsk region is: detection of the disease during the period of tick activity, that is, in the early stages; equal ratio of erythema and non-erythhema forms; the prevalence in the clinic of mild symptoms of intoxication; laboratory confirmation in 75% of cases in the early stages. The presence of migratory erythema in the patient gives reason for the diagnosis of ixodiс tick-borne borreliosis even in the absence of positive results of a serological examination.

The role of host phenology for parasite transmission

Phenology is a fundamental determinant of species distributions, abundances, and interactions. In host-parasite interactions, host phenology can affect parasite fitness due to the temporal constraints it imposes on host contact rates. However, it remains unclear how parasite transmission is shaped by the wide range of phenological patterns observed in nature. We develop a mathematical model of the Lyme disease system to study the consequences of differential tick developmental-stage phenology for the transmission of B. burgdorferi. Incorporating seasonal tick activity can increase B. burgdorferi fitness compared to continuous tick activity but can also prevent transmission completely. B. burgdorferi fitness is greatest when the activity period of the infectious nymphal stage slightly precedes the larval activity period. Surprisingly, B. burgdorferi is eradicated if the larval activity period begins long after the end of nymphal activity due to a feedback with mouse population dynamics. These results highlight the importance of phenology, a common driver of species interactions, for the fitness of a parasite.