Methodological considerations in injury burden of disease studies across Europe: a systematic literature review.

BACKGROUND: Calculating the disease burden due to injury is complex, as it requires many methodological choices. Until now, an overview of the methodological design choices that have been made in burden of disease (BoD) studies in injury populations is not available. The aim of this systematic literature review was to identify existing injury BoD studies undertaken across Europe and to comprehensively review the methodological design choices and assumption parameters that have been made to calculate years of life lost (YLL) and years lived with disability (YLD) in these studies. METHODS: We searched EMBASE, MEDLINE, Cochrane Central, Google Scholar, and Web of Science, and the grey literature supplemented by handsearching, for BoD studies. We included injury BoD studies that quantified the BoD expressed in YLL, YLD, and disability-adjusted life years (DALY) in countries within the European Region between early-1990 and mid-2021. RESULTS: We retrieved 2,914 results of which 48 performed an injury-specific BoD assessment. Single-country independent and Global Burden of Disease (GBD)-linked injury BoD studies were performed in 11 European countries. Approximately 79% of injury BoD studies reported the BoD by external cause-of-injury. Most independent studies used the incidence-based approach to calculate YLDs. About half of the injury disease burden studies applied disability weights (DWs) developed by the GBD study. Almost all independent injury studies have determined YLL using national life tables. CONCLUSIONS: Considerable methodological variation across independent injury BoD assessments was observed; differences were mainly apparent in the design choices and assumption parameters towards injury YLD calculations, implementation of DWs, and the choice of life table for YLL calculations. Development and use of guidelines for performing and reporting of injury BoD studies is crucial to enhance transparency and comparability of injury BoD estimates across Europe and beyond.

Molecular epidemiology of Cryptosporidium spp. in calves in Estonia: high prevalence of Cryptosporidium parvum shedding and 10 subtypes identified.

We investigated the molecular epidemiology of Cryptosporidium spp. in Estonia by testing fecal samples from 486 calves aged <2 months, raised on 53 cattle farms, for the presence of Cryptosporidium DNA. The parasites were identified and characterized by sequencing of the 18S rRNA gene and of the 60 kDa glycoprotein (gp60) gene. Moreover, using a questionnaire, we surveyed factors that could be relevant for animal-to-human and human-to-animal transmission of Cryptosporidium spp. on the farms. Cryptosporidium spp. were shed by 23% of the investigated calves and at least one shedding calf was found on 66% of the farms. Cryptosporidium parvum was the most common species shed, while C. bovis and C. ryanae were also detected. More than half of the calves aged 8-14 days shed C. parvum. Nine previously described C. parvum subtypes (IIaA14G1R1, IIaA16G1R1, IIaA17G1R1, IIaA18G1R1, IIaA19G1R1, IIaA20G1R1, IIaA21G1R1, IIaA22G1R1 and IIaA16G2R1) and an apparently novel subtype IIlA21R2 were found. Calves from farms that reported spreading manure on fields during spring had 10 times higher odds to shed Cryptosporidium spp. in their feces than calves from farms that did not. Calves aged 8-14 days had higher odds to shed IIa18G1R1 as well as IIaA16G1R1 than younger calves.

Prevalence of cysticercosis in Estonian pigs and cattle.

Taenia solium has been ranked as the most important foodborne parasite and Taenia saginata as the most commonly found human Taenia tapeworm worldwide. The last official reports of taeniosis from Estonia were in 2003 for T. solium and 2012 for T. saginata. By law, all animal cases of cysticercosis must be registered and reported when found. Our aim was to estimate the prevalence of cysticercosis in Estonia caused by T. solium in pigs and T. saginata in cattle. The four slaughterhouses participating in the study slaughter between them approximately 80% of pigs and cattle in Estonia annually. Sampling spanned from February to April 2014, visiting the slaughterhouses five times per week. Visual inspection, palpation, and incisions at predilection sites were used to find cysts in both species. The sites inspected in both species were the external masseter, tongue, heart, and diaphragm. In addition, the internal masseter in pigs was examined, and the internal pterygoid muscle and esophagus in cattle. DNA was extracted from the cysts and used for PCR amplification of the cox1-gene for Taenia genus and species identification. A total of 564 cattle and 1217 pigs were examined. Cysts were found in 0.36% (n = 2; CI 0.06-1.17) of cattle and in 0.08% (n = 1; CI 0.004-0.40) of pigs. Cestode PCR was negative from all cysts. Results should be considered taking into account the low sensitivity and specificity of finding cysts. Results reflect the situation in larger slaughterhouses, and the possibility that the situation in smaller slaughterhouses is different should not be excluded.

Review of Cryptosporidium and Giardia in the eastern part of Europe, 2016.

IntroductionThis paper reviews the current knowledge and understanding of Cryptosporidium spp. and Giardia spp. in humans, animals and the environment in 10 countries in the eastern part of Europe: Bosnia and Herzegovina, Croatia, Czech Republic, Estonia, Hungary, Latvia, Poland, Romania, Serbia and Slovenia. Methods: Published scientific papers and conference proceedings from the international and local literature, official national health service reports, national databases and doctoral theses in local languages were reviewed to provide an extensive overview on the epidemiology, diagnostics and research on these pathogens, as well as analyse knowledge gaps and areas for further research. Results:Cryptosporidium spp. and Giardia spp. were found to be common in eastern Europe, but the results from different countries are difficult to compare because of variations in reporting practices and detection methodologies used. Conclusion: Upgrading and making the diagnosis/detection procedures more uniform is recommended throughout the region. Public health authorities should actively work towards increasing reporting and standardising reporting practices as these prerequisites for the reported data to be valid and therefore necessary for appropriate control plans.

How does supplementary feeding affect endoparasite infection in wild boar?

Supplementary feeding is widely used in game management but may aid the transmission of parasites. Firstly, feeding sites attract animals and may be regarded as high-risk areas for parasite transmission. Secondly, high host population densities resulting from and supported by supplementary feeding, as well as accumulation of parasites in the environment, may increase parasite prevalence. Our aim was to investigate whether host density or the number of feeding sites drives endoparasite infection in an Estonian wild boar (Sus scrofa) population. For this, we collected wild boar faeces from forests, and soil samples from supplementary feeding sites in central and south-eastern Estonia. The role of host density and number of feeding sites on both the risk and mean abundance of endoparasite infection was modelled using generalized linear models (GLM). The presence of biohelminths in faecal samples was associated with both wild boar and feeding site density, whereas the presence of Eimeria sp. oocysts in faecal samples was only associated with wild boar density. Helminth eggs were found more often from the soil of active and abandoned feeding sites than from control areas. This could reflect parasitic contamination or indicate that supplementary feeding sites are suitable habitat for soil-dwelling nematodes. These results suggest that the effects of supplementary feeding on parasite prevalence in wild boar are mediated by the characteristics of parasite life cycles.

Seasonal recovery of Eimeria oocysts from soil on naturally contaminated pastures.

Though Eimeria is an important parasite of cattle, research is lacking on how the parasite persist in the pasture soils. In this study, feces samples were collected from three pastures in June and October 2010 and soil samples in April 2011. Coordinates of sampling locations were recorded with Global Positioning System together with information about grass cover, shade, and elevation. All soil samples were collected from the same locations as the fecal samples and used in model evaluating the possible factors influencing the concentration of oocysts in the soil. Feces and soil samples were investigated using a quantitative flotation technique. Eimeria oocysts were found in 95.6% of fecal samples collected in summer and 84.5% of samples in fall. In contrast, the same locations soil samples were positive for Eimeria oocysts in 37.3% (summer) and 44.3% (fall). Despite larger numbers of oocysts in fecal samples shed during summer compared to fall, there was no difference in the concentration of oocysts in soil samples the following spring. The odds of higher numbers of oocysts in soil samples in spring were higher if fecal samples collected in summer were in shade or if containing Eimeria alabamensis during the fall. Factors other than the concentrations of oocysts shed in feces appear to affect whether oocysts persist between grazing seasons.

Persistence of Eimeria bovis in soil.

Eimeriosis is a disease that occurs globally and often affects cattle grazing on pastures contaminated with oocysts of the pathogenic species Eimeria bovis, Eimeria zuernii or Eimeria alabamensis, respectively. Nonetheless, little is understood regarding oocyst persistence on the pasture. The study was performed in the temperate climate zone. Soil samples were spiked with 100,000 E. bovis oocysts in July 2010 or with 50,000 oocysts in October 2010, respectively, both either with our without addition of cattle faeces. The soil samples were exposed to natural environmental conditions until April 2011. A subset of the samples was analysed immediately after spiking as positive control. The oocysts were recovered by a flotation method and counted in a reading chamber. On average, 23 % of the oocysts could be recovered from the positive control. The recovery of oocysts dropped to 0.30 % of the original level in the samples prepared in July independent of the addition of faeces, whereas the oocyst count was higher in the samples prepared in October, both without (2.05 %) and with (2.64 %) faecal material. No differences were observed between presence of oocysts or oocyst counts recovered in the presence or absence of faeces. Presence of faeces had a positive influence on oocyst integrity. During the winter season, the number of oocysts in the soil was lowered under the detection limit in most samples. On the other hand, the comparatively short 3-month summer period had a significant influence on the number of persisting oocysts too.

Is livestock production prepared for an electrically paralysed world?

Politics, insolvency, increased technological complexity and solar flares are factors that currently present uncomfortably real threats to our increasing dependency on electricity. In some scenarios, there may be no warning before electronic and mechanical help will cease to function. Industrial food production appears to be particularly vulnerable. Making preparations for an electrically paralysed period may not only be prudent, and a matter of national security, but might also push scientific efforts in agricultural production past energy reduction and towards more resilient and sustainable options.

Coxiella burnetii Seroprevalence and Associated Risk Factors in Cattle, Sheep, and Goats in Estonia.

Q fever, a disease caused by Coxiella burnetii (CB), is an emerging zoonotic health problem. The prevalence data from potential sources are valuable for assessing the risk to human and animal health. To estimate the prevalence of CB antibodies in Estonian ruminants, pooled milk and serum samples from cattle (Bos taurus) and pooled serum samples from sheep (Ovis aries) and goats (Capra hircus) were analyzed. Additionally, bulk tank milk samples (BTM; n = 72) were analyzed for the presence of CB DNA. Questionnaires and herd-level datasets were used to identify the risk factors for exposure using binary logistic regression analysis. The prevalence of CB-positive dairy cattle herds (27.16%) was significantly higher than that in beef cattle herds (6.67%) and sheep flocks (2.35%). No CB antibodies were detected in the goat flocks. CB DNA was found in 11.36% of the BTM samples. The odds of seropositivity were higher in dairy cattle herds, with an increasing number of cattle in the herd, and with location in southwestern, northeastern and northwestern Estonia. Dairy cattle herds had higher odds of testing positive for CB in BTM if the dairy cows were kept loose and lower odds if the herd was located in northwestern Estonia.

Analysis of reservoir sources of Campylobacter isolates to free-range broilers in Denmark.

Campylobacter is a common cause of food poisoning in many countries, with broilers being the main source. Organic and free-range broilers are more frequently Campylobacter-positive than conventionally raised broilers and may constitute a higher risk for human infections. Organic and free-range broilers may get exposed to Campylobacter from environmental reservoirs and livestock farms, but the relative importance of these sources is unknown. The aim of the study was to describe similarities and differences between the genetic diversity of the Campylobacter isolates collected from free-range/organic broilers with those isolated from conventional broilers and other animal hosts (cattle, pigs, and dogs) in Denmark to make inferences about the reservoir sources of Campylobacter to free-range broilers. The applied aggregated surveillance data consisted of sequenced Campylobacter isolates sampled in 2015 to 2017 and 2018 to 2021. The data included 1,102 isolates from free-range (n = 209), conventional broilers (n = 577), cattle (n = 261), pigs (n = 30), and dogs (n = 25). The isolates were cultivated from either fecal material (n = 434), food matrices (n = 569), or of nondisclosed origin (n = 99). Campylobacter jejuni (94.5%) dominated and subtyping analysis found 170 different sequence types (STs) grouped into 75 clonal complexes (CCs). The results suggest that CC-21 and CC-45 are the most frequent CCs found in broilers. The relationship between the CCs in the investigated sources showed that the different CCs were shared by most of the animals, but not pigs. The ST-profiles of free-range broilers were most similar to that of conventional broilers, dogs and cattle, in that order. The similarity was stronger between conventional broilers and cattle than between conventional and free-range broilers. The results suggest that cattle may be a plausible reservoir of C. jejuni for conventional and free-range broilers, and that conventional broilers are a possible source for free-range broilers or reflect a dominance of isolates adapted to the same host environment. Aggregated data provided valuable insight into the epidemiology of Campylobacter sources for free-range broilers, but time-limited sampling of isolates from different sources within a targeted area would hold a higher predictive value.

Systematic review of products with potential application for use in the control of Campylobacter spp. in organic and free-range broilers.

Campylobacter spp. are some of the most important food-borne zoonoses in Europe and broiler meat is considered the main source of Campylobacter infections. Organic and free-range broilers have access to outdoor reservoirs of Campylobacter and are more frequently infected at slaughter than the conventional broiler flocks. Limitations to biosecurity and treatment options in these production types calls for additional solutions. This review examines intervention methods with sufficient strength and quality, which are able to reduce the load of Campylobacter safely and efficiently and discuss their applicability in organic and free-range broiler production. Four different products passed the inclusion criteria and their quality examined: ferric tyrosine chelate, a prebiotic fermentation product of Saccharomyces cerevisiae, short-chain fatty acid butyrate coated on microbeads added to feed, and a mix of organic acids added to the drinking water. Though potential candidates for reducing Campylobacter in broilers were identified, there is a lack of large scale intervention studies that demonstrate an effect under field conditions of a free-range broiler production.

Trichinella spp. in Wild Boars (Sus scrofa), Brown Bears (Ursus arctos), Eurasian Lynxes (Lynx lynx) and Badgers (Meles meles) in Estonia, 2007-2014.

In this study, we summarize Trichinella findings from four wild, free-ranging host species from Estonia during 2007-2014. Trichinella spp. larvae were detected in 281 (0.9%, 95% confidence interval (CI) 0.8-1.0) of 30,566 wild boars (Sus scrofa), 63 (14.7%, 95% CI 11.6-18.3) of 429 brown bears (Ursus arctos), 59 (65.56%, 95% CI 55.3-74.8) of 90 Eurasian lynxes (Lynx lynx), and three (60.0%, 95% CI 18.2-92.7) of five badgers (Meles meles). All four European Trichinella species were detected: T. britovi in 0.7% of the wild boars, 7.2% of the brown bears, 45.6% of the lynxes, and 40.0% of the badgers; T. nativa in 0.1% of the wild boars, 5.8% of the brown bears, and 20.0% of the lynxes; T. pseudospiralis in 0.02% the wild boars; and T. spiralis in 0.03% of the wild boars and 4.4% of the lynxes. The results include the first description from Estonia of T. britovi in brown bear and badgers, T. pseudospiralis in wild boars, and T. spiralis in wild boars and lynxes. The results indicate high infection pressure in the sylvatic cycles across the years-illustrating continuous risk of spillover to domestic cycles and of transmission to humans.

HERBIVORES AS ACCIDENTAL HOSTS FOR TRICHINELLA: SEARCH FOR EVIDENCE OF TRICHINELLA INFECTION AND EXPOSURE IN FREE-RANGING MOOSE (ALCES ALCES) IN A HIGHLY ENDEMIC SETTING.

Herbivores can be accidental hosts for the zoonotic nematode parasites Trichinella spp., which are endemic at high prevalence in wildlife in northeastern Europe. Using direct and indirect detection methods for Trichinella spp., we investigated samples from 463 wild moose (Alces alces) harvested by hunters in Estonia in 2015. A total of 460 moose were tested directly by artificial digestion of diaphragm muscle, 463 moose were tested indirectly by enzyme-linked immunosorbent assay (ELISA), and 34 moose also by western blot. Positive-control reference sera were from other host species. Nematode larvae were found in six muscle samples; five of which were pooled samples. None of the larvae were identified as Trichinella spp., based on their morphology and molecular analyses. Twelve moose (2.6%) were positive by ELISA, but none were positive by the western blot test. Trichinella spp. infection was not detected, but ELISA results may suggest Trichinella spp. exposure in a small proportion of moose in Estonia.

The Zoonotic Parasite Dirofilaria repens Emerged in the Baltic Countries Estonia, Latvia, and Lithuania in 2008-2012 and Became Established and Endemic in a Decade.

The zoonotic parasite Dirofilaria repens has spread toward north in Europe, and cases of autochthonous dirofilariosis caused by D. repens have emerged in the Baltic countries Estonia, Latvia, and Lithuania. We conducted a review on the emergence of dirofilariosis in humans and domestic dogs in these three countries in northeastern Europe. Based on the available literature and reports, the first finding in the Baltic countries was made in Latvia in 2008, followed by the first in Lithuania in 2010, and the first in Estonia in 2012. In all three countries, further findings were reported soon after the first reports. By the end of 2019, autochthonous human D. repens infections had been described from Latvia and Lithuania, and autochthonous canine D. repens infections had been described from all three Baltic countries. While no epidemiological studies estimating prevalence or incidence of the human infections have been published from the three countries, a substantial proportion of investigated dogs have tested positive for microfilariae in studies performed in Latvia and Lithuania. Dirofilariosis is an emerging zoonosis in northern Europe, and the summarized data confirm that D. repens has become established and endemic in the Baltic countries. The available data do not provide a good overview of the situation, and further epidemiological studies are needed. Awareness about the recently emerged zoonotic parasite should be increased among medical doctors, veterinarians, and the general public. Managing this zoonotic infection is a public health challenge that needs to be addressed using a One Health approach. Investigating the spread of D. repens in the Baltic countries could be useful for better preparedness for the anticipated further spread to the Nordic countries.

Leptospira spp. in Cats in Estonia: Seroprevalence and Risk Factors for Seropositivity.

Leptospirosis is a zoonotic bacterial disease that affects humans and animals worldwide. Recently, more attention has been paid to Leptospira spp. infections in domestic cats. In this seroepidemiological study, we estimated the prevalence of anti-Leptospira spp. antibodies in domestic cats in Estonia and evaluated risk factors for the seropositivity. A total of 546 surplus feline plasma and serum samples, collected in collaboration with small animal clinics and an animal shelter in 2013 and 2015, were included in this study. The samples were tested for antibodies against Leptospira spp. using a microscopic agglutination test. The panel included Leptospira interrogans serovars Pomona, Icterohaemorrhagiae, Bratislava, Canicola, and Hardjo, and Leptospira kirschneri serovar Grippotyphosa. Titers ≥100 (positive reactions at dilutions ≥1/100) were considered positive. Anti-Leptospira spp. antibodies were detected in 12.8% of the cats. The percentage of cats that tested positive for antibodies against L. interrogans serovars Pomona, Icterohaemorrhagiae, Bratislava, Canicola, and Hardjo were 9.3%, 3.5%, 2.4%, 0.4%, and 0.2%, respectively, and the percentage of cats that tested positive for antibodies against L. kirschneri serovar Grippotyphosa was 7.3%. Of the seropositive cats, 46.5%, 35.2%, 12.7%, 4.2%, and 1.4% tested positive for 1, 2, 3, 4, and 5 serovars, respectively. The prevalence of anti-Leptospira spp. antibodies was 11.2% in pet cats and 16.3% in shelter cats. Among pet cats, the seroprevalence was over four times higher in cats that had access to the outdoors (17.2%) than in indoor cats (3.9%). Multivariable models, one based on data on pet cats only and another including also data on shelter cats, identified having access to the outdoors, being a shelter cat, and being from Western Estonia as the risk factors for seropositivity. Cats could be better protected from exposure to Leptospira spp. by not allowing them to roam freely outdoors.

Herd factors influencing oocyst production of Eimeria and Cryptosporidium in Estonian dairy cattle.

Cryptosporidium and Eimeria are intestinal parasites which are sensitive to the surroundings, behaviour and well-being of their host. In the present study, a range of factors related to farm management systems, environment, housing and herd characteristics were investigated with regard to alterations in oocyst excretion in cattle, using a mixed-effects model. Information and samples for three age categories were obtained from 45 Estonian dairy farms, located in 15 counties. Leaving the calf with the mother after birth reduced the risk of shedding higher levels of Cryptosporidium (OR = 0.20) and Eimeria (OR = 0.68) oocysts in all animals. The calves younger than 3 months kept on farms housing at least 150 animals had less risk (OR = 0.39) of producing higher numbers of Cryptosporidium oocysts. A somewhat lower infection level was observed in 3- to 12-month-old animals housed in separate buildings (OR = 0.64). The chance of shedding higher levels of Eimeria doubled (OR = 2.27) in cattle older than a year in case a vacancy period was used before replacing animals in pens and tripled (OR = 2.94) when the relative humidity exceeded 75% in the cowshed. Winter reduced the odds (OR = 0.25) of shedding Eimeria oocysts in the oldest animals compared to the fall season. Simple changes in handling and housing of cattle may produce a positive effect on controlling coccidian infections in Estonian dairy herds.

Coxiella burnetii Antibody Prevalence and Risk Factors of Infection in the Human Population of Estonia.

Q fever is an emerging health problem in both humans and animals. To estimate the prevalence of Coxiella burnetii (C. burnetii) antibodies in the Estonian population, we analyzed plasma samples from 1000 individuals representing the general population and 556 individual serum samples from five population groups potentially at a higher risk (veterinary professionals, dairy cattle, beef cattle, and small ruminant stockbreeders and hunters). Additionally, 118 dairy cow bulk tank milk samples were analyzed to establish the infection status of the dairy cattle herds and the participating dairy cattle keepers. Questionnaires were used to find the potential risk factors of exposure. The effects of different variables were evaluated using binary logistic regression analysis and mixed-effects logistic analysis. The prevalence in veterinary professionals (9.62%; p = 0.003) and dairy cattle farmers (7.73%; p = 0.047) was significantly higher than in the general population (3.9%). Contact with production animals in veterinary practice and being a dairy stockbreeder in C. burnetii positive farms were risk factors for testing C. burnetii seropositive (p = 0.038 and p = 0.019, respectively). Results suggest that C. burnetii is present in Estonia and the increased risk of infection in humans is associated with farm animal contact.

Large-Scale Epidemiological Study on Toxoplasma gondii Seroprevalence and Risk Factors in Sheep in Estonia: Age, Farm Location, and Breed Associated with Seropositivity.

Toxoplasma gondii is a zoonotic parasite of major veterinary and public health importance. The parasite is common in many host species in Estonia, however, information about the seroprevalence in the local sheep population is lacking. We estimated T. gondii seroprevalence and evaluated a limited selection of possible risk factors for T. gondii seropositivity in sheep raised in Estonia. Sera from 1599 sheep from 122 flocks, collected during 2012-2013, were diluted to 1:40 and screened for the presence of anti-T. gondii immunoglobulin G antibodies using a commercial direct agglutination test. The cutoff titer for seropositivity was 40. A total of 667 of the 1599 sheep were T. gondii seropositive, yielding an apparent seroprevalence estimate of 41.71% (95% confidence interval 39.31-44.14). At least one seropositive sheep was detected on the majority (88.53%) of the farms. T. gondii seroprevalence was significantly lower in lambs (age <12 months) than in adults (age ≥12 months) (11.11% and 42.16%, respectively). The seroprevalence increased steeply with age in the first years of life. A multivariable random-effects logistic regression model identified being an adult (odds ratio [OR] 9.55) and being from a farm located on the islands (OR 2.51) as risk factors for T. gondii seropositivity, while being of Texel breed appeared as a protective factor (OR 0.34) when compared with the Estonian Blackhead breed. Exposure to T. gondii was widespread among the investigated sheep. Undercooked meat and unpasteurized milk from sheep from Estonia should be considered possible sources of T. gondii infections to other hosts, including humans.

Anti-Ascaris suum IgG antibodies in fattening pigs with different respiratory conditions.

During their migration through the pig's body, Ascaris suum larvae cause significant damage to the lungs. Little is known about the actual impact of this tissue damage on the occurrence and severity of respiratory problems in industrial pig fattening farms. In this study, we evaluated the link between the serological response to two different A. suum antigen preparations and respiratory or meat inspection outcomes. Two different serological tests were used that measure antibodies against either the A. suum haemoglobin molecule or complete homogenate of the 3rd stage larva that migrate through the lungs. Firstly, serum samples were analysed that were collected from 19 herds in which the cause of acute clinical respiratory symptoms was either Actinobacillus pleuropneumoniae, A. suum, or a miscellaneous cause. This was done to test whether serological results could confirm pathological findings. Secondly, serum samples from 60 herds of finishing pigs with a history of high or low frequency of pleuritis at meat inspection (MI), but without acute respiratory symptoms at the time of sampling, were also submitted for serological evaluation using both tests. Regression models were used to search for potential associations between the proportion of pigs testing seropositive with MI results, in particular pathological changes related to the lungs. The results of both ELISAs were strongly associated (P < 0.001) with pigs belonging to a herd where the respiratory problems could be attributed to A. suum by histology, indicating that both tests can be used to diagnose clinical respiratory outbreaks due to A. suum. In the herds without acute clinical respiratory symptoms, a positive association was found between the proportion of pigs testing seropositive and the percentage of livers rejected due to milk spots and with whole carcass condemnations. No association was found between Ascaris serology and lung pathology (pneumonia and pleuritis) registered at MI, however, challenging the likely involvement of Ascaris in the development of these lesions.

Toxoplasma gondii seroprevalence in extensively farmed wild boars (Sus scrofa) in Denmark.

Toxoplasma gondii is a zoonotic parasite of worldwide importance. In this study, we estimated T. gondii seroprevalence in extensively farmed wild boars in Denmark, where little is known about T. gondii in animal hosts. Our study focused on wild boars because they are considered good indicator species for the presence of T. gondii, and wild boar meat is used for human consumption. Serum samples from 101 wild boars collected in 2016-2018 from five different locations from the continental part of Denmark, Jutland, were screened for anti-T. gondii antibodies. The samples were analysed using a commercial indirect enzyme-linked immunosorbent assay (ELISA). Samples from 28 (27.7%) of the 101 wild boars tested positive with the ELISA. The odds for a wild boar to test seropositive were higher if it was sampled during the hunting season 2017-2018 than during 2016-2017 and if it was reported to be at least 1 year old than if it was younger (logistic regression model with the two variables: odds ratios 17.5 and 3.9, respectively). A substantial proportion of the investigated extensively farmed wild boars had been exposed to T. gondii. Moreover, the parasite appeared widespread, at least in the continental part of Denmark, Jutland, as seropositive wild boars were found from all five sampled locations. Assuming seropositivity indicates hosting viable parasites, consumption of undercooked wild boar meat from Denmark is a potential source of T. gondii infections to other hosts, including humans.