Toxoplasma gondii in sheep: Serological occurrence at slaughterhouse level in Italy and environmental risk factors

Toxoplasmosis is a parasitic disease affecting a wide range of species, including humans, and can be responsible for important clinical manifestations such as abortion and neurological signs. Sheep show a remarkable susceptibility to its causative agent, Toxoplasma gondii, and zoonotic transmission may occur in case of consumption of undercooked meat obtained from infected animals. Toxoplasma gondii seroprevalence in sheep can significantly vary on a geographical basis, as shown by numerous surveys conducted worldwide. To investigate environmental and climate conditions that may affect the likelihood of ovine infection, 405 serum samples from selected sheep raised in 91 farms were collected from two abattoirs, with each abattoir receiving animals from two regions (1/Tuscany-Latium and 2/Campania-Basilicata). The seroprevalence of infection in all examined animals was 53.8%. Young animals (n = 165) had a lower likelihood of being T. gondii positive compared to the adults (OR = 0.21), and the seropositive rate of animals slaughtered in abattoir 2 was significantly higher than that of animals slaughtered in abattoir 1 (60.5 vs. 43.2%, p < 0.01). The significant bioclimatic variables (p < 0.05) associated with the presence of T. gondii antibodies were related to areas with a lower range of temperature and higher precipitation. In conclusion, this study expands on the interpretation of serological data, with the inclusion of environmental and climatic variables, as possible risk factors in the spread of toxoplasmosis in the study area. These findings provide novel insights to support public health measures, such as risk-based control plan, and contribute to a "One Health" approach, taking into account the environmental and climatic perspectives.

West Nile and Usutu viruses co-circulation in central Italy: outcomes of the 2018 integrated surveillance

BACKGROUND

West Nile (WNV) and Usutu (USUV) are emerging vector-borne zoonotic flaviviruses. They are antigenically very similar, sharing the same life cycle with birds as amplification host, Culicidae as vector, and man/horse as dead-end host. They can co-circulate in an overlapping geographic range. In Europe, surveillance plans annually detect several outbreaks.

METHODS

In Italy, a WNV/USUV surveillance plan is in place through passive and active surveillance. After a 2018 WNV outbreak, a reinforced integrated risk-based surveillance was performed in four municipalities through clinical and serological surveillance in horses, Culicidae catches, and testing on human blood-based products for transfusion.

RESULTS

Eight WNV cases in eight equine holdings were detected. Twenty-three mosquitoe catches were performed and 2367 specimens of Culex pipiens caught; 17 pools were USUV positive. A total of 8889 human blood donations were tested, and two asymptomatic donors were USUV positive.

CONCLUSIONS

Different surveillance components simultaneously detected WNV only in horses and USUV only in humans and mosquitoes. While in endemic areas (i.e. northern Italy) entomological surveillance is successfully used as an early detection warning, this method in central Italy seems ineffective. To achieve a high level of sensitivity, the entomological trapping effort should probably exceed a reasonable balance between cost and performance. Besides, WNV/USUV early detection can be addressed by horses and birds. Further research is needed to adapt the surveillance components in different epidemiological contexts.

Aedes albopictus (Diptera: Culicidae) Monitoring in the Lazio Region (Central Italy)

The Asian tiger mosquito Aedes albopictus (Skuse 1894) is assuming an ever-increasing importance as invasive species in Europe and consequently as human health and nuisance concern. In Central Italy, the species has been recently involved in a chikungunya outbreak. A 3 yr Ae. albopictus monitoring was carried out in 21 municipalities of the Lazio region (Central Italy), belonging to three provinces. Samplings were performed on a weekly basis using ovitraps, in order to investigate climatic and spatial variables driving egg abundance and Ae. albopictus period of activity. A temperature of 10.4°C was indicated as lower threshold for the onset of egg-laying activity, together with a photoperiod of 13:11 (L:D) h. The whole oviposition activity lasted 8 mo (May-December), with 95% of eggs laid between early June and mid-November and a peak at the end of August. Egg abundance was positively influenced by accumulated temperature (AT) of the 4 wk preceding sampling and negatively by precipitation during the week before. Egg-laying activity dropped with decreasing AT, increasing rainfall, and with a photoperiod below 10:14 (L:D) h. Our results pinpointed the importance of fine-scaled spatial features on egg abundance. Some of these fine-scaled characteristics have been highlighted, such as the presence of vegetation and human footprint index. Our model estimated an almost doubled maximum number of laid eggs for the maximum value of human footprint. Compelling evidence of the relevance of fine-scaled characteristics was reported, describing cases where human-made breeding sites driven the abundance of Ae. albopictus.

Seroprevalence and risk factors associated with exposure to Leishmania infantum in dogs, in an endemic Mediterranean region

Canine leishmaniasis (CanL) is a zoonotic parasitic disease caused by Leishmania infantum in the Mediterranean area and transmitted by phlebotomine sand fly vectors. The domestic dog is the main reservoir host. The aim of this study was to assess the influence of different individual, environmental and spatial risk factors on the dog exposure to L. infantum and to estimate the seroprevalence among owned and kennel dogs, in the Lazio region (central Italy), where canine leishmaniasis is endemic. In the period 2010-2014, 13,292 sera from kennel and owned dogs were collected by official and private veterinarians. The presence of anti-Leishmania IgG was analysed by indirect fluorescent antibody test (IFAT), using a 1:80 titre cut-off. At the univariable analysis, CanL seropositivity was associated with sex, size, breed, coat length, living with other dogs and forest/semi-natural land cover. At the multivariable analysis, age, ownership and attitude were confirmed as risk factors, being more than 2 years old, owned, and hunting dogs at higher risk. Being a Maremma sheepdog was a protective factor. A true overall seroprevalence of 6.7% (95% CI: 6.2-7.2) was estimated in the whole population while 7.3% (95% CI: 6.8-7.8) was estimated in kennel dogs and 74.3% (95% CI: 70.8-77.6) in owned dogs. The role of kennels as a key component for CanL active and passive surveillance was also highlighted. This study confirmed the endemicity of CanL in the Lazio region and focused some factors that can influence the seropositivity of dogs in a Mediterranean region.

Cross-sectional serosurvey of Coxiella burnetii in healthy cattle and sheep from extensive grazing system in central Italy

A cross-sectional survey was carried out to estimate the seroprevalence of Coxiella burnetii in extensively grazed cattle and sheep from central Italy and to identify the related risk factors. Data on notified human Q fever cases in the area were also collected and described. A two-stage cluster sampling was performed. A total of 5083 animals (2210 cattle; 2873 sheep) belonging to 186 farms (92 herds; 94 flocks) were tested for the presence of antibodies against C. burnetii using a commercial enzyme-linked immunosorbent assay kit. The prevalence at the animal-level resulted three times higher in sheep compared to cattle (37.8% vs. 12.0%; χ2 = 270.10, P < 0.001). The prevalence at the herd-level was also higher in sheep than in cattle (87.2% vs. 68.5%; χ2 = 9.52, P < 0.01). The multivariate analysis showed a higher risk of seropositivity for cattle aged 67-107 months (OR 2.79, 95% CI 1.86-4.18), cattle >107 months of age (OR 2.07, 95% CI 1.36-3.14) and mixed breed cattle (OR 1.74, 95% CI 1.11-2.72). A herd size >92 animals was recognized as herd-level risk factor in cattle (OR 6.88, 95% CI 1.67-28.37). The risk of being seropositive was double in sheep belonging to flocks >600 animals (odds ratio (OR) 2.04, 95% CI 1.63-2.56). Sheep were confirmed to be the most exposed species. Nevertheless, the prevalence observed in cattle also suggests the potential involvement of this species in the circulation of the pathogen in the area. Seven confirmed human Q fever cases were reported. In five out of seven cases there was at least one exposed herd within a 5 km buffer. Even though the source of the infection was not identified, the possibility of C. burnetii circulating in the livestock and human population in the study area cannot be overlooked. The integration between veterinary and human surveillance will be crucial to understand the spread of this zoonosis and to support the adoption of appropriate control measures.

A cross-sectional serosurvey in a sheep population in central Italy following a bluetongue epidemic

Bluetongue (BT) is a viral disease that affects ruminants and is transmitted by midges of the genus Culicoides spp. The seroprevalence, the clinical form and the occurrence rates significantly differ in relation to several factors such as bluetongue virus (BTV) serotype, host species, breed susceptibility, specific previous exposure, vector ecology, husbandry and health status. Following the 2001-2006 BTV2 and BTV16 epidemics in central Italy, a new epidemic caused by BTV1 occurred in 2013-2015 causing 398 outbreaks in a susceptible population of about 1 million ruminants. The present study assessed the BTV1 seroprevalence in the sheep population of central Italy by conducting two cross-sectional surveys, in the proximity of and within BT outbreak farms. A total of 2,984 sheep from 437 farms were sampled. The animal-level prevalence was 19% (95% CI: 17-21%), the between-herd prevalence was 46% (95% CI: 41-51%) and the within-herd prevalence was 21% (95% CI: 16-26%). Risk factors were investigated by logistic regression models. Living on a farm where an outbreak occurred and the number of outbreaks in proximity of the farm were identified as risk factors, while herd size was identified as a protective factor. This study represents the first BT survey in southern Europe and reports valuable findings on BTV epidemiology. Despite intensive virus circulation, the estimated seroprevalences were low. The assessment of the population immunity level is crucial for defining an efficient vaccination strategy and for predicting the impact of future virus circulation. In view of the low seroprevalence detected albeit an extensive BTV1 circulation, the population immunity was likely to be inadequate in preventing new BTV1 epidemics. Moreover, considering the recurrent introduction of new serotypes from North Africa and the Balkans, the control of multi-serotype BTV infections will continue to present a challenge in the near future.

Angiostrongylus vasorum in wolves in Italy: prevalence and pathological findings

Background

Angiostrongylus vasorum is a nematode residing in the heart and pulmonary vessels of dogs and wild carnivores. In Europe the red fox is its reservoir, while only three records from wolves have been published. Angiostrongylus vasorum has a worldwide distribution, and many pieces of evidence demonstrate that it is spreading from endemic areas to new ones. In Italy, A. vasorum was reported with increasing frequency in dogs and foxes in the last decades, and now it is considered endemic throughout the country. Angiostrongylus vasorum can be asymptomatic or cause respiratory and circulatory disorders, at times causing severe disseminated infections.

Methods

Between February 2012 and December 2016, 25 wolves found dead in central Italy were submitted to the Istituto Zooprofilattico del Lazio e della Toscana for post-mortem examination. Samples of lungs, heart, liver, spleen, kidneys, mediastinic lymph nodes and brain were collected from each animal for histological examination. When adult and larval nematodes were microscopically seen in lungs, the other organs were processed, and five histological sections for each organ were examined. To confirm parasite identification, lung samples were submitted to a PCR-sequencing protocol targeting the ITS2 region of A. vasorum.

Results

Seven wolves (28.0%) harboured nematode larvae in lung sections. In two of the positive wolves, adult nematodes were visible in pulmonary arteries, in four animals larvae were also detected in other organs. DNA sequencing reactions confirmed parasite identification as A. vasorum in all the cases.

Conclusions

As a result of the high prevalence of A. vasorum reported in wolves in the present study, a focus of high circulation could be hypothesised in central Italy. Nevertheless, the similarly high prevalence in foxes originating from the same areas were reported in previous papers. Histopathological evidence highlights the pathogenic potential of A. vasorum in the wolf, especially in juvenile animals.

Single incision sling (Ajust™) for the treatment of female stress urinary incontinence: 2-year follow-up

OBJECTIVE

The primary outcome of this study was to evaluate the subjective and objective outcomes of an adjustable Single Incision Sling (Ajust™ C.R. Bard Inc., New Providence, NJ, USA) for the treatment of SUI, with a 2-year follow-up. The secondary outcome was to evaluate the safety of this procedure and the impact of this mini-sling on the filling and voiding phases of the bladder.

STUDY DESIGN

In our prospective multicenter study we included 95 females with a clinical symptomatic and urodynamic diagnosis of primary SUI, and unsuccessful previous conservative treatment. Cure rate was evaluated objectively, using a standardized cough stress test and subjectively using the patient global impression of improvement. The King's Health questionnaire was used to evaluate quality of life (QoL). Urgency was evaluated using the patient perception of intensity of urgency scale. Complications were assessed intra-, peri- and post-operatively. All patients underwent urodynamic studies pre-operatively and at 6 months. The McNemar chi-square test was used to compare categorical variables, the paired t-test for continuous parametric variables, and the Fisher exact test for continuous non-parametric variables. A logistic regression model and odds ratios (with 95 percent confidence intervals) were used to assess the independent prognostic value of four variables for the outcome (age, parity, body mass index and menopausal status).

RESULTS

92 Patients completed the 2-year follow-up. The objective cure rate was 83.7% and the subjective cure rate was 81.5%. De novo urgency was present in 9 patients (9.8%) and was associated with de novo urge incontinence in 6 patients (6.5%). Only 1 patient with de novo urge incontinence showed de novo detrusor overactivity. Regarding QoL, the King's Health Questionnaire indicated a statistically significant improvement in all domains except sleep. We observed no intraoperative complications. Post-operatively 1 patient referred pain in the right leg, 3 patients had mesh extrusions, 1 patient had recurrent urinary tract infections. Post-operative urodynamics showed a statistically significant increase of detrusor pressure at maximum flow and a reduction of maximum flow rate. No patients were obstructed according to the Blaivas and Groutz nomogram.

A spatial, statistical approach to map the risk of milk contamination by &beta;-hexachlorocyclohexane in dairy farms

In May 2005, beta-hexachlorocyclohexane (β-HCH) was found in a sample of bovine bulk milk from a farm in the Sacco River valley (Latium region, central Italy). The primary source of contamination was suspected to be industrial discharge into the environment with the Sacco River as the main mean of dispersion. Since then, a surveillance programme on bulk milk of the local farms was carried out by the veterinary services. In order to estimate the spatial probability of β- HCH contamination of milk produced in the Sacco River valley and draw probability maps of contamination, probability maps of β-HCH values in milk were estimated by indicator kriging (IK), a geo-statistical estimator, and traditional logistic regression (LR) combined with a geographical information systems approach. The former technique produces a spatial view of probabilities above a specific threshold at non-sampled locations on the basis of observed values in the area, while LR gives the probabilities in specific locations on the basis of certain environmental predictors, namely the distance from the river, the distance from the pollution site, the elevation above the river level and the intrinsic vulnerability of hydro-geological formations. Based on the β-HCH data from 2005 in the Sacco River valley, the two techniques resulted in similar maps of high risk of milk contamination. However, unlike the IK method, the LR model was capable of estimating coefficients that could be used in case of future pollution episodes. The approach presented produces probability maps and define high-risk areas already in the early stages of an emergency before sampling operations have been carried out.

Completeness of the dog registry and estimation of the dog population size in a densely populated area of Rome

In most European countries, registration and identification of dogs is compulsory. In Italy, the national dog registry is composed of regional dog registries. Although dog registries have been established for many years, the issue related to completeness of data has not been addressed so far. The objective of this study was twofold: first to assess the completeness of data of the dog registry through telephone interview of a sample of dog owners drawn from the dog registry, then to estimate the total owned dog population in 4 boroughs of Rome. For the second objective, a capture-recapture method was applied using data from the dog registry and data from a face-to-face questionnaire submitted to people waiting in the sitting room of 5 points of access for booking and payment of primary and specialist care. Different scenarios are proposed to verify the assumptions of the estimation procedure and potential biases are discussed. The completeness of data of the dog registry was 88.9% (95% CI: 85.8-91.9%) and the owned-dog population was estimated at 26,244 dogs (95% CI: 24,110-28,383). The dog registry is an important source of information especially when it is properly updated and completeness of data is known.

[Animal biomonitoring and micropollutants in public health--review]

The aim of the present review is to provide a picture of the current knowledge on animal biomonitoring and on the link between pollution and Public Health. There are various reasons leading to this road: the need of early detection of industrial pollutants, especially micropollutants that have adverse effects in very low concentrations: it is important to disclose the presence of these compounds directly or through certain molecular biomarkers in living organisms rather than in the natural environment, where they are often below the detection threshold; the need to optimize the allocation of resources: some experiences of biomonitoring carried out in wild animals may be useful in the identification of pollution sources; however, biomonitoring of domestic animals appears to be more feasable and effective, because they share with humans the exposure to pollutants. Nowadays, professionals of different disciplines such as doctors and biologists do not share a common set of terms and definitions in animal biomonitoring: this review wants to give a contribution in the consolidation of the current knowledge under a common language.

[Beta-hexachlorocyclohexane contamination in dairy farms of the Sacco River Valley, Latium, Italy, 2005. A retrospective cohort study]

OBJECTIVE

in March 2005, the Italian National Monitoring System on Chemical Residuals in Food of Animal Origin detected levels of the pesticide beta-hexachlorocyclohexane (ß-HCH) that were 20 times higher than the legal limit of 0.003 mg/kg in bulk milk from a dairy farm in the Sacco River valley. ß-HCH, a lindane isomer and possible human carcinogen, was subsequently found in milk from several neighboring farms. A study was therefore undertaken to evaluate the extent and risk factors for contamination.

DESIGN

all dairy cattle farms in the valley were enrolled in a retrospective cohort study and their bulk milk analyzed for ß-HCH. A questionnaire was administered to farmers to evaluate possible exposure factors.

SETTING AND PARTICIPANTS

cases: dairy farms with at least one result indicating ß-HCH ≥ 0.002 mg/kg in bulk milk during the period april-june 2005; exposure: feeding animals on fodder cultivated in soils watered with and/or flooded by river water; participants: IZSLT, RMG Local Health Unit, FR Local Health Unit.

MAIN OUTCOME MEASURES

attack rate, relative risk, attributable proportion among exposed.

RESULTS

of 244 farms tested, 34 met the case definition (attack rate 14%). The exposure to fodder cultivated in soils watered with and/or flooded by river water was observed in 33/34 (97%) case-farms and in 23/210 (10.9%) of those with contamination <0.002 mg/kg in bulk milk (RR 110.8; 95%CI 15.5- 792). Attributable proportion among exposed was more than 99%.

CONCLUSION

fodder cultivated near a contaminated river was the main risk factor for ß-HCH contaminated milk. On the basis of the epidemiologic evidence and laboratory testing, watering local fields with river water and production of fodder in farms with contaminated soil was banned, and all the animals from positive farms were culled.

Biotic and abiotic factors influencing distribution and abundance of Culicoides obsoletus group (Diptera: Ceratopogonidae) in central Italy

In the framework of a bluetongue surveillance program including clinical, serological, and entomological activities, Culicoides biting midges were light trapped weekly in two regions of central Italy, Lazio and Tuscany. In the period January 2002 through December 2005, 3,944 collections were carried out in 189 trap sites distributed in all the provinces of the two regions. Abundance data of C. obsoletus group were analyzed in relation to trap site altitude, distance from the sea, land use, and number of farmed animals. Species seasonality and overall temporal trend were also described. C. obsoletus was distributed over the whole study area, almost in all trapping sites and with high abundances. The species group was dominant among all captured Culicoides, with higher abundances recorded inland and in areas where land cover was partially or completely natural-wooded. Adults on the wing were caught all year round, with peaks in May-June and middle October. The observed trend through years recorded a peak during autumn 2002, in concomitance with a local epidemic of bluetongue.

Ehrlichia infection in Italy

Immunoglobulin M seroconversion to Ehrlichia chaffeensis was documented in U.S. citizens bitten by ticks in Sardinia. Seven cases of suspected ehrlichiosis in local residents were not confirmed by laboratory tests. In Alpine areas antibodies to E. phagocytophila were detected in persons at high risk, i.e., foresters (8.6%) and hunters (5.5%), and in controls (1.5%). Of 153 persons bitten by ticks, only one was Ehrlichia antibody-positive after 6 months.