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With the objective of studying the role of wild fauna in the epidemiology of fasciolosis disease, a definitive wild-host inventory was carried out in a french farm where infected domestic hosts (cows) cohabit with wild potential ones. Liver flukes, faecal eggs and antibodies were looked for in lagomorphs (Oryctolagus cuniculus) and rodents (Myocastor coypus, Ondatra zybethicus, Rattus norvegicus, Arvicola sapidus and micromammal species) trapped in the study area. Presence of Fasciola hepatica was detected in two species: O. cuniculus and M. coypus. Infection rates were respectively 34 % (42/124) and 55 % (106/193). Liver flukes were found in 78 M. coypus (n = 192) and 11 O. cuniculus (n = 35). No other species was infected by F. hepatica. The number of animals shedding fluke eggs was higher in M. coypus (49 out of 1 27 sampled; 38.6 %) than in O. cuniculus (two out of 17 sampled; 11.7 %).The results indicate that M. coypus may play a role in the maintenance and the dissemination of F. hepatica in various environments and open a discussion on the role of other natural wild hosts.

The State of Uttarakhand in India has been studying the Jamrani Multipurpose Project in the last 40 years. The government’s feasibility study has been completed and all statutory clearances were obtained. It comprises the construction of a 150-meter-high roller compacted concrete dam across the Gola River, a 14-megawatt toe powerhouse, the expansion and modernization of irrigation canal systems and a drinking water component. The project benefits will include 117 million liters per day drinking water for Haldwani Town, increased water availability for 150,000 ha cultivable command area and annual energy generation of 63 gigawatt-hour as a byproduct. The project is estimated to cost $365 million and was proposed in 2019 for the Asian Development Bank’s financial assistance. A memorandum of understanding was signed in 2018 between the states of Uttarakhand and Uttar Pradesh, defining how the cost and benefits will be shared. The paper will discuss the ADB project appraisal process and describe the steps being taken to confirm and enhance the project economic feasibility, improve the mitigation of environmental and social impacts and review and confirm the technical studies.

The article discusses a study which investigated the prevalence of infectious agents in honey bees in western France. Topics covered include the drastic decline in the pollinating insect population, the use of polymerase chain reaction (PCR) methods in quantifying sample contents and the high prevalence of infectious agents found in terms of colonies and of apiaries. Also mentioned is the assessment of the survival of the colonies after the wintering season.

A continuous in vitro culture system for Babesia divergens was initiated from a human isolate. It was maintained through 305 subcultures for 3 years using a low concentration of serum and a low haematocrit, with no decrease in the initial virulence. This in vitro system enabled the routine culture of all human and bovine B. divergens isolates thus far tested, with a mean parasitaemia level of 30%-40%. Different cytological aspects observed in the same isolate by optical and electron microscopy were described in parasitized ox, gerbil and human erythrocytes. The sequence of B. divergens antibody responses was determined in man and ox, enabling the precise identification of major B. divergens antigens as candidates for vaccines. [ABSTRACT FROM AUTHOR]

Tick-borne encephalitis (TBE) is a viral disease endemic in Eurasia. The virus is mainly transmitted to humans via ticks and occasionally via the consumption of unpasteurized milk products. The European Centre for Disease Prevention and Control reported an increase in TBE incidence over the past years in Europe as well as the emergence of the disease in new areas. To better understand this phenomenon, we investigated the drivers of TBE emergence and increase in incidence in humans through an expert knowledge elicitation. We listed 59 possible drivers grouped in eight domains and elicited forty European experts to: (i) allocate a score per driver, (ii) weight this score within each domain, and (iii) weight the different domains and attribute an uncertainty level per domain. An overall weighted score per driver was calculated, and drivers with comparable scores were grouped into three terminal nodes using a regression tree analysis. The drivers with the highest scores were: (i) changes in human behavior/activities; (ii) changes in eating habits or consumer demand; (iii) changes in the landscape; (iv) influence of humidity on the survival and transmission of the pathogen; (v) difficulty to control reservoir(s) and/or vector(s); (vi) influence of temperature on virus survival and transmission; (vii) number of wildlife compartments/groups acting as reservoirs or amplifying hosts; (viii) increase of autochthonous wild mammals; and (ix) number of tick species vectors and their distribution. Our results support researchers in prioritizing studies targeting the most relevant drivers of emergence and increasing TBE incidence.

Partial migration is a pervasive albeit poorly studied phenomenon by which some individuals of a population migrate while others are residents. It has tremendous consequences on seasonal variations of population size/structure and therefore management. Using a multi-event capture-mark-recapture/recovery (CMR) approach, we assessed seasonal site occupancy, survival and site fidelity of a partially migratory diving duck, the Common pochard (Aythya ferina), in an area potentially including both local breeders and winter visitors. The modelling exercise indeed discriminated two different categories of individuals. First, locally breeding females which had a probability of being present in our study area during winter of 0.41. Females of this category were found to be more faithful to their breeding site than males (breeding site fidelity probabilities of 1 and 0.11, respectively). The second category of birds were winter visitors, which included adults of both sexes, whose probability of being present in the study area during the breeding season was nil, and young of both sexes with a 0.11 probability of being present in the area during the breeding season. All wintering individuals, among which there was virtually no locally breeding male, displayed a high fidelity to our study area from one winter to the next (0.41-0.43). Estimated annual survival rates differed according to age (adults 0.69, young 0.56). For both age classes mortality was higher during late winter/early spring than during summer/early winter. Our study is among the first to show how and under which conditions the multi-event approach can be employed for investigating complex movement patterns encountered in partial migrants, providing a convenient tool for overcoming state uncertainty. It also shows why studying patterns of probability of individual presence/movements in partial migrants is a key towards understanding seasonal variations in numbers.

Background: The honey bee, Apis mellifera, is frequently used as a sentinel to monitor environmental pollution. In parallel, general weakening and unprecedented colony losses have been reported in Europe and the USA, and many factors are suspected to play a central role in these problems, including infection by pathogens, nutritional stress and pesticide poisoning. Honey bee, honey and pollen samples collected from eighteen apiaries of western France from four different landscape contexts during four different periods in 2008 and in 2009 were analyzed to evaluate the presence of pesticides and veterinary drug residues., Methodology/findings: A multi-residue analysis of 80 compounds was performed using a modified QuEChERS method, followed by GC-ToF and LC-MS/MS. The analysis revealed that 95.7%, 72.3% and 58.6% of the honey, honey bee and pollen samples, respectively, were contaminated by at least one compound. The frequency of detection was higher in the honey samples (n = 28) than in the pollen (n = 23) or honey bee (n = 20) samples, but the highest concentrations were found in pollen. Although most compounds were rarely found, some of the contaminants reached high concentrations that might lead to adverse effects on bee health. The three most frequent residues were the widely used fungicide carbendazim and two acaricides, amitraz and coumaphos, that are used by beekeepers to control Varroa destructor. Apiaries in rural-cultivated landscapes were more contaminated than those in other landscape contexts, but the differences were not significant. The contamination of the different matrices was shown to be higher in early spring than in all other periods., Conclusions/significance: Honey bees, honeys and pollens are appropriate sentinels for monitoring pesticide and veterinary drug environmental pollution. This study revealed the widespread occurrence of multiple residues in beehive matrices and suggests a potential issue with the effects of these residues alone or in combination on honey bee health.

In a region-wide serologic study carried out in 2004 on free-ranging hunted roe deer in various landscapes, we found that 58% of the animals (237 out of 406) were antibody positive for Babesia divergens antigen. Serologic and infection status was also analyzed for 327 roe deer live-trapped in two fenced forest areas over 5 yr (2004-08). For two consecutive years during this period, 92 and 94% of the deer in these closed populations were antibody-positive for B. divergens. Babesia spp. were isolated in autologous red blood cell culture for 131 of the trapped animals (40%). Molecular typing was done on 76 isolates with polymerase chain reaction (PCR)-restriction fragment length polymorphism methods targeted at the 18S ribosomal subunit gene (18 isolates) and the Bd37 gene coding for a merozoïte surface antigen implicated in a protective response (60 isolates). Results indicated continuous cocirculation of B. capreoli and B. venatorum in both forests and possible coinfection of animals with both species. No infection with B. divergens was detected. Fifteen isolates were confirmed to be B. capreoli by sequencing part of the 18S rRNA gene. Using PCR detection of the Bd37 gene, all nine isolates of B. venatorum in this study were negative, whereas the 15 confirmed and 50 putative B. capreoli isolates showed very variable restriction profiles, distinct from those known for Bd37 in B. divergens. Two isolates showed conflicting results, suggestive of mixed infection.

This study focused on Oeosophagostomum sp., and more especially on O. bifurcum, as a parasite that can be lethal to humans and is widespread among humans and monkeys in endemic regions, but has not yet been documented in apes. Its epidemiology and the role played by non-human primates in its transmission are still poorly understood. O. stephanostomum was the only species diagnosed so far in chimpanzees. Until recently, O. bifurcum was assumed to have a high zoonotic potential, but recent findings tend to demonstrate that O. bifurcum of non-human primates and humans might be genetically distinct. As the closest relative to human beings, and a species living in spatial proximity to humans in the field site studied, Pan troglodytes is thus an interesting host to investigate. Recently, a role for chimpanzees in the emergence of HIV and malaria in humans has been documented. In the framework of our long-term health monitoring of wild chimpanzees from Kibale National Park in Western Uganda, we analysed 311 samples of faeces. Coproscopy revealed that high-ranking males are more infected than other individuals. These chimpanzees are also the more frequent crop-raiders. Results from PCR assays conducted on larvae and dried faeces also revealed that O. stephanostomum as well as O. bifurcum are infecting chimpanzees, both species co-existing in the same individuals. Because contacts between humans and great apes are increasing with ecotourism and forest fragmentation in areas of high population density, this paper emphasizes that the presence of potential zoonotic parasites should be viewed as a major concern for public health. Investigations of the parasite status of people living around the park or working inside as well as sympatric non-human primates should be planned, and further research might reveal this as a promising aspect of efforts to reinforce measures against crop-raiding.

We report in vitro culture of zoonotic Babesia sp. EU1 from blood samples of roe deer in France. This study provides evidence of transovarial and transstadial transmission of the parasite within Ixodes ricinus, which suggests that this tick could be a vector and reservoir of EU1.

Babesia divergens, the main causative agent of bovine babesiosis in Western Europe, was isolated from naturally infected cattle. Ninety-six blood samples were examined by means of an in vitro culture technique in sheep erythrocytes: 19 of them were collected from animals in the acute phase of the disease with visible parasitemia on blood smears, while the 77 remaining animals showed no microscopically detectable parasites. B. divergens was cultured from the 19 first blood samples as well as from 31 samples collected from asymptomatic animals. The time period before parasites could be detected in the culture varied in the latter samples from 6 to 20 days. The effects of sampling condition (anticoagulant used) and storage length were tested. A good correlation was obtained between immunofluorescent antibody test and culture, with identical results (positive or negative) for 89.6% of the samples collected from asymptomatic animals. The sensitivity of the in vitro culture method was determined and was about 10 parasites/mL of whole blood from three independent experiments performed with three different isolates, confirming its suitability to detect and culture diverse B. divergens isolates from carrier cattle. The parasites could indeed be isolated 9 months after the acute babesiosis phase in the blood of naturally infected animals. The 50 isolates collected in this study were successfully subcultured, cryopreserved and resuscitated using the same culture medium. The in vitro isolation of B. divergens from asymptomatic carrier cattle was achieved and will allow the analysis of parasite diversity within cattle herds.

Parasitic diseases, like babesiosis and theileriosis are transmitted by ticks: their occurrence is therefore linked to the size of the tick stock and the seasonality of the vectors. Babesia divergens bovine babesiosis transmitted by Ixodes ricinus is widespread and often reported in France. Serological prevalence is high, ranging from 20 to 80% according to the farms. Clinical incidence is low: around 0.4% for the whole cattle population. The endemic situation is unstable and clinical cases occur more frequently with farming system modifications. L. ricinus is a tick essentially found in woodlands and so, for the most part, is found in closed rural areas. The situation of the other bovine babesiosis (Babesia major) and theileriosis (Theileria orientalis) is not well documented in France. However, the epidemiology of parasitic diseases is changing, especially because of changes in the environmental characteristics, i.e. both farm and herd management conditions and also climatic conditions. These modifications can provoke an increase in the tick stocks, an increase in the contact rate between cattle and ticks, and an increase in the contact rate between cattle and the wild fauna, especially deer. This results in likely modifications of the endemic situation, with a higher risk of clinical babesiosis in the medium term.

Babesia divergens was cultivated in sheep erythrocytes in RPMI 1640 supplemented with 10% Fetal Calf Serum (FCS) or sheep serum. In vitro cultures in sheep red blood cells were initiated with human erythrocytes infected in vitro with B. divergens Rouen 1987 or with gerbil blood infected with several isolates from bovine origin. After the first subcultures on sheep erythrocytes, a ten-fold multiplication of the parasites was obtained within 48 h. Erythrocytes from three splenectomized sheep were infected in vitro with B. divergens; when parasitaemia reached 10%, the animals were inoculated with homologous parasitized erythrocytes. All sheep expressed hyperthermia with a peak between the 6th and the 9th day post-infection (p-i) and a transitory parasitaemia 10 days p-i. In vitro primary cultures were performed on two of these sheep, demonstrating the parasite persistence at very low parasitaemia in the infected animals. Splenectomized sheep can be used as a new model for B. divergens chronic infection.

To clarify the role of the nutria Myocastor coypus in the epidemiology of domestic fasciolosis in Loire-Atlantique (department of western France), 438 nutrias were trapped in 9 humid areas of the department and 304 nutrias were trapped in 3 farms where Fasciola hepatica was present; all animals were necropsied. Liver flukes were found in 160 nutrias: 38 nutrias randomly taken in the department (8.7%) and 122 trapped in fasciolosis areas (40.1%). The average parasitic burden was 5.7 flukes per nutria. Sixty-five percent of the liver flukes measured more than 18 mm (size of sexual maturity). The coproscopic examinations carried out on 144 infected nutrias showed that 90% of the infected nutrias shed fluke eggs. The hatching rate was 39.6%. Two groups of 100 Lymnaea truncatula snails, originating from 2 different populations, were exposed to F. hepatica miracidiae hatched from eggs collected from infected nutrias. The prevalence of the infection was 74% and 58.6% in the 2 groups of snails. The average redial burden was 6.2 rediae per snail. The total number of metacercariae was 72.4 metacercariae per snail producing cercariae. Two groups of 5 sheep were orally infected by 150 metacercariae of nutria or sheep origin, respectively. The installation rates of F. hepatica in sheep were respectively 31.6% and 29.6% for the two groups. Specific antibody kinetics of sheep were similar whether the metacercariae were of nutria or sheep origin. M. coypus allows the complete development of F. hepatica and releases parasitic elements that are infective for domestic ruminants. Because of its eco-ethologic characteristics, the nutria could be a potential wild reservoir of F. hepatica in France.

Babesia divergens cause of bovine babesiosis transmitted by Ixodes ricinus, is widely spread especially in West, Central and South-West parts of France. It occurs with two annual peaks, in spring and autumn. The study was carried out during a period of two years (1991-1993) in four farms in the Sarthe area, in order to know the distribution and the ecology of I. ricinus, and to show the presence of B. divergens. Cattle are parasitised as early as March essentially by adult ticks, according to a seasonal distribution (spring, autumn). The flag method allows to catch essentially the larvae and the nymphs on the pastures; nymphs appear as early as March, and larvae one to two months later. Ectoparasite collection on trapped micromammals (Apodemus sylvaticus, Clethrionomys glareolus, etc.) in pastures hedges, is used to detect small I. ricinus populations, mostly larvae. A new ELISA method has been used for the study of the kinetics of anti-B. divergens antibodies in 236 cattle during two years. Most of the animals (60%) show a high antibody level, essentially at the end of the pasture season; the percentage of positive animals decreases during winter and increases again during the pasture season. Calves become seropositive since their first months on pastures. Adults show asymptomatic infections several times along the year, mostly during spring and autumn; only three clinical babesiosis cases have been observed during the whole study, in animals exhibiting nevertheless a high specific antibody level.

This study aims to assess the relationships between the phyto-ecological characteristics of grazing pastures and their risk of being infested by the hard tick Ixodes ricinus. To that purpose, 128 pastures belonging to 20 dairy farms were observed from April to July 1994. The farms were located in western France. Assessment of the tick population was made by four monthly, blanket-dragging sessions. The average infestation rate was 40.2%. Six types of pastures were identified according to their basic phyto-ecological characteristics using a factorial analysis of correspondences followed by a hierarchical ascending classification. These identified types were significantly related to the infestation rates, thereby making it possible to provide a predictive value in risk assessment. The infestation rates were high (96% on average) in two types of pastures characterized by their proximity to woods, and low (13%) in two other types characterized by seeded grass species located at some distance from woods, and intermediate (39% on average) in the last two types.

Data collected from a longitudinal survey carried out over a 2-year period, in four dairy herds in western France, were used to assess Babesia divergens antibody kinetics. Farms were visited once a month. The total number of animals monitored was 236 including calves, heifers and cows of the Holstein and Normande breeds. An ELISA was used to follow the humoral response levels against Babesia divergens. When the study began, in the autumn of 1991 (200 animals), half of the animals were already seropositive (57.5%). In all four herds, the percentage of positive animals decreased during winter, and increased during spring. Antibody levels remained stable in 49 animals, high for some, very low or negative for others. Most seropositive animals showed at least one antibody peak at some time during the 2-year period, but some presented two to five. Among the calves, 61.3% showed seroconversion during the first pasture season. Similarly, 60% of the newly purchased cows showed increases in antibody levels during the 3 months after their introduction into a new herd, regardless of the initial antibody level. Only three dairy cows had expressed a clinical babesiosis, these cows were already seropositive. Clinical incidence is low in the four farms, nevertheless serological prevalence and incidence are high.

Data collected from a longitudinal survey carried out over 2 years on four farms in western France were used to assess the incidence and infestation of Ixodes ricinus on rodents. Once a month, on each farm, 25 Sherman live traps were set in hedges bordering selected pastures. A total of 799 micromammals were examined, including Apodemus sylvaticus, Clethrionomys glareolus, Microtus agrestis, Microtus arvalis, and Crocidura spp. Larvae and nymphs of I. ricinus were found. Small numbers of Ixodes (Exopalpiger) trianguliceps were also recovered from each farm. The mean infestation rate of the I. ricinus larvae (1.6-5.9) among all animals examined varied between farms Most animals were infested by only a single tick, but one M. agrestis harboured 43 I. ricinus larvae. Larvae or nymphs were found throughout the year, with peaks from March to October.

Data collected from a longitudinal survey carried out over a 2 year period in four herds located in western France were used to assess the infestation level in cattle by female ixodes ricinus and to describe its seasonality. Farms were visited once a month. The population studied consisted of calves, heifers and dairy cows (of Holstein and Norman de breeds). The total number of animals monitored varied from 207 to 173 throughout the study, because of the culling of dairy cows and birth of calves. The infestation level by l ricinus varied from one herd to another. Heifers were found to have a greater level of infestation than dairy cows and calves. The infestation rate appeared to be low, ie, most animals (between 47 and 83%) were infested by only one tick in the axilla. The seasonal distribution of ticks showed two peaks, one in spring and a second lower one in autumn, with slight fluctuations between herds and years. The number of ticks on cattle and the percentage of infested animals showed a parallel seasonality.

A longitudinal survey was carried out during a 2 year period in Western France to assess the infestation level of grazing pastures by Ixodes ricinus ticks. Four farms were visited once a month and each of the grazing pastures was sampled in the centre and at the border using the blanket dragging method. A total of 3562 I. ricinus (34 adults, 900 nymphs and 2628 larvae) were collected and the infestation was significantly higher during the first year (p < 0.0001). The infestation level by I. ricinus varied between grazing pastures and farms. Grazing pastures in the vicinity of forest were more infested than the others, all through the study. The seasonal distribution of ticks showed peaks, with low fluctuations between farms, years and stages. Tick abundance could not be related to vegetation, but only to the vicinity of woods.

A sample of 110 lactating dairy cows was examined to describe the attachment sites of female Ixodes ricinus ticks and to assess whether counts on one or two body areas can predict infestation and its level. Seventy per cent of the cows were infested by I. ricinus and the average tick burden on the infested cows was 15, ranging from 1 to 136. Preferred attachment sites were the axilla, udder/groin, neck, dewlap and flank. Udder/groin and axilla carried respectively 35.3% and 44.1% of the total tick burden. To predict infestation (yes/no), sensitivity of counts on axilla, on udder/groin and on both areas was respectively, 76.6%, 80.6% and 94.8%. Total burden prediction equations based on count on axilla and udder/groin are presented.