Prevalence and genetic characterization of Toxoplasma gondii in naturally infected backyard pigs intended for familial consumption in Romania

BACKGROUND

Foodborne toxoplasmosis in humans can be due to the exposure to tissue cysts of Toxoplasma gondii through the consumption of meat, including pork, of infected animals. Traditional Romanian food habits include pork as the preferred meat, while backyard pig rearing remains a common practice in many rural areas of Romania. The aims of the present study were to estimate the prevalence of T. gondii infection in naturally infected backyard pigs slaughtered for familial consumption and to genetically characterize the T. gondii strains obtained.

METHODS

Paired blood and heart samples were collected from 94 backyard pigs, home slaughtered for private consumption. Serum samples were analyzed using the immunofluorescence antibody test (IFAT) for anti-T. gondii antibody detection. Heart samples were screened by polymerase chain reaction (PCR) targeting the 529-bp repeat region (REP529) for T. gondii detection. In addition, heart samples from IFAT positive animals were bioassayed in mice. The T. gondii isolates were genotyped by the analysis of 15 microsatellite markers.

RESULTS

The results showed that almost half of the pigs investigated were T. gondii seropositive (46.8%, 95% confidence interval (CI): 36.4-57.4%) and in more than a quarter of the pigs (26.6%, 95% CI: 18.0-36.7%), the parasite was detected by PCR. Three (3/44) T. gondii strains were isolated from hearts of seropositive pigs and they all belonged to genotype II.

CONCLUSIONS

The present study showed the presence of T. gondii infection in backyard pigs in Romania, which suggests that consumption of pork from animals reared and slaughtered at home may pose a potential threat to human health and should be given attention. In addition, to our knowledge, this is the first study to provide data concerning T. gondii strains circulating in pigs from Romania.

The life history and feeding ecology of velvet shell, Velutina velutina (Gastropoda: Velutinidae), a specialist predator of ascidians

Velvet shell, Velutina velutina (Müller, 1776), is a specialist predator of ascidians, like other members of the gastropod family Velutinidae. Globally, invasive ascidians have become problematic, ecologically and economically, yet ecological knowledge of velutinids remains limited. This study outlines the life history and feeding ecology of V. velutina in eastern Canada based on laboratory work complemented by field observations. The life history of V. velutina is closely linked with ascidians, which serve as prey and protection for their egg capsules. Egg capsules were embedded within tunics of Aplidium glabrum (Verrill, 1871) and Ascidia callosa Stimpson, 1852, with a preference for the latter. Seasonal behavioural shifts were consistent annually and corresponded with seawater temperature cycles. Feeding dominated during the coldest months (January–May), growth occurred as water temperature increased to the annual maximum (June and July), transitioning to mating during the warmest period (July–August), and egg capsule deposition dominated as water temperature declined (November–January). Larvae hatched between January and July after 2–4 months of development. Velutina velutina preyed on all ascidian species presented during this study, including golden star tunicate, Botryllus schlosseri (Pallas, 1766), and vase tunicate, Ciona intestinalis (Linnaeus, 1767), two non-indigenous species, although solitary species were preferred.

The native European Aedes geniculatus mosquito species can transmit chikungunya virus

Europe is the world’s leading tourism destination and is receiving every year travellers from areas with active arbovirus transmission. There is thus a threat of mosquito-borne virus emergence in Europe due to the presence of the invasive mosquito vector Aedes albopictus. Little attention has been paid about the possible role of indigenous mosquito species as vectors of emerging arboviruses. Here, we assessed the vector competence dynamic of Aedes geniculatus, a European anthropophilic mosquito species, for chikungunya virus (CHIKV) in comparison with an European population of Ae. albopictus. We revealed that Ae. geniculatus is highly susceptible to CHIKV infection and could transmit the virus. By specifically exploring the vector competence dynamic in both mosquito species, we revealed that the cumulative distribution of CHIKV incubation period in Ae. geniculatus was delayed by several days as compared to Ae. albopictus. Our results strengthen the importance of considering indigenous species as potential vectors for emerging arboviruses. They also revealed the importance of considering variation in arbovirus dissemination or transmission dynamics in mosquitoes when performing vector competence assays. We will discuss the implications of our results on a CHIKV outbreak dynamic in a theoretical framework.

Virulence of atypical Toxoplasma gondii strains isolated in French Guiana in a murine model

Background. Toxoplasma gondii is an obligate intracellular protozoan parasite of warm-blooded vertebrates. Most infections in immunocompetent patients are asymptomatic. However, since 2000s, strains with particular genetic profiles that differ from the known clonal type (type I, II, III), have been described. In French Guiana, these strains are highly pathogenic in immunocompetent patients. They have defined a new clinical entity called Amazonian Toxoplasmosis. The present study aims to further improve our knowledge on the pathogenicity of these Amazonian T. gondii strains in comparison with three reference strains using Swiss strain mice. With these data, we tried to establish a predictive virulence score to classify these strains, but also to correlate this virulence with the severity of the disease in infected patients. Results. All the virulence indicators revealed that the Amazonian strains isolated in French Guiana presented a high virulence profile, but lower than the highly virulent type I reference RH strain. The findings reveal differences in virulence between human and animal strains, but also between anthropized and wild strains. Conclusion. In addition to being a clinically relevant animal model of Amazonian Toxoplasmosis, this model could also provide a solid experimental basis for future studies aiming to investigate the underlying mechanisms of Amazonian Toxoplasmosis disease.

[Seroprevalence of Toxoplasmosis among Pregnant Women in Benin: Meta-Analysis and Meta-Regression]

To assess the seroprevalence of toxoplasmosis among pregnant women in Benin, we conducted a meta-analysis using the PRISMA criteria. Al research published between 1990 and 2018 on toxoplasmosis among pregnant women Benin were eligible. A total of five databases were investigated, and the extracted data were subjected to a meta-analysis under R 3.1 using both random effect model and fixed effect model. The overall prevalence of toxoplasma-specific IgG among pregnant women was 47% (CI 95%: 40-53) and that of specific IgM was 2% (CI 95%: 1-3). The infection rate in urban areas (52%) was significantly higher than in rural areas (33%). The two main risk factors identified by the various eligible studies were the age of the pregnant women and the consumption of raw vegetables. We show that toxoplasmosis is endemic in pregnant women in Benin, implying that primary prevention measures must be put in place by the competent authorities to control this infection.

The introduction of new hosts with human trade shapes the extant distribution of Toxoplasma gondii lineages

Toxoplasma gondii is a zoonotic protozoan with a worldwide occurrence, but the determinants of the current pattern in the geographical distribution of T. gondii lineages and strains remain poorly understood. To test the influence of human trade on T. gondii populations, we conducted a population genetic study of 72 T. gondii animal isolates from Senegal, a West African country in which the ongoing inland progress of invasive murine hosts (introduced in port cities of Senegal since the 16th century by European sailors) is well described. Isolates were mainly collected on free-range poultry, which are considered as relevant bioindicators of T. gondii strain diversity in the domestic environment. Sampling was conducted in two port cities of Senegal (Dakar and Saint-Louis) and in one inland region (Kedougou). Population genetic analyses using 15 microsatellite markers revealed different patterns between port cities where lineages non-virulent for mice (type II, type III, and Africa 4) were predominant, and Kedougou where the mouse-virulent Africa 1 lineage was the most common. By considering the current spatial pattern in the inland progress of invasive rodents in Senegal, our results suggest that the invasive house mouse Mus musculus domesticus counter-selects the Africa 1 lineage in the invaded areas. The comparison of the microsatellite alleles of type II strains from Senegal to type II strains from other areas in Africa and Western Europe, using discriminant analysis of principal components and Network analysis, point to a mainly Western European origin of the type II lineage in Senegal. Collectively, these findings suggest that human-mediated intercontinental migrations of murine hosts are important vectors of T. gondii strains. Differential susceptibility of endemic and introduced murine hosts to various T. gondii strains probably determines the persistence of these strains in the environment, and therefore their availability for human and animal infection.

Exposure of yellow-legged gulls to Toxoplasma gondii along the Western Mediterranean coasts: Tales from a sentinel

Efficiently tracking and anticipating the dynamics of infectious agents in wild populations requires the gathering of large numbers of samples, if possible at several locations and points in time, which can be a challenge for some species. Testing for the presence of specific maternal antibodies in egg yolks sampled on the colonies could represent an efficient way to quantify the exposure of breeding females to infectious agents, particularly when using an abundant and widespread species, such as the yellow-legged gull (Larus michahellis). We used such an approach to explore spatio-temporal patterns of exposure to Toxoplasma gondii, a pathogenic protozoan responsible of toxoplasmosis in humans and other warm-blooded vertebrates. First, we tested the validity of this approach by exploring the repeatability of the detection of specific antibodies at the egg level using two different immunoassays and at the clutch level using an occupancy model. Then, samples gathered in 15 colonies from France, Spain and Tunisia were analysed using an immunoassay detecting antibodies specifically directed against T. gondii. Prevalence of specific antibodies in eggs was overall high while varying significantly among colonies. These results revealed that T. gondii circulated at a large spatial scale in the western Mediterranean yellow-legged gull population, highlighting its potential role in the maintenance community of this parasite. Additionally, this study illustrates how species commensal to human populations like large gulls can be used as wildlife sentinels for the tracking of infectious agents at the human-wildlife interface, notably by sampling eggs.

Seroprevalence of Toxoplasma gondii in commensal rodents sampled across Senegal, West Africa

Risks related to Toxoplasma gondii infection in humans remain poorly known in Senegal. Although rodent surveys could help to assess the circulation of T. gondii, they have seldom been set up in sub-Saharan Africa. The aim of this study was to examine Toxoplasma seroprevalence in rodents from villages and towns across Senegal. Rodents were sampled in 40 localities using a standardised trapping protocol. Detection of T. gondii antibodies was performed on 1205 rodents, using a modified agglutination test (MAT) technique. Seroprevalence data were analysed depending on geography, the local rodent community, and individual characteristics of the rodent hosts. We found 44 seropositive rodents from four different species (Mastomys erythroleucus, Mastomys natalensis, Mus musculus domesticus, Rattus rattus). Toxoplasma seroprevalence was low, averaging 4% in the localities. Higher Toxoplasma seroprevalence (up to 24%) was found in northern Senegal, a region known to be the heart of pastoral herding in the country.

Prevalence of toxoplasmosis and genetic characterization of Toxoplasma gondii strains isolated in wild birds of prey and their relation with previously isolated strains from Turkey

Toxoplasma gondii is a protozoon parasite that causes congenital toxoplasmosis, as well as other serious clinical presentations, in immune compromised humans. Analyses of the prevalence and genotyping of strains from the definitive host and intermediate hosts will help to understanding the circulation of the different strains and elucidating the role of the genotype(s) in human toxoplasmosis. Turkey has a specific geographic location bridging Africa, Europe, and Asia. We hypothesized that T. gondii strains may have been transferred to Turkey from these continents via migratory birds or vice versa. The present study aimed to assess the prevalence of toxoplasmosis in wild birds of prey of İzmir and Manisa provinces as well as genetically characterize T. gondii strains from these wild birds to show the relation between bird strains and neighboring stray cats as well as human strains previously isolated in Turkey. Tissues obtained from 48 wild birds were investigated for the presence of T. gondii DNA and then bioassayed in mouse. Isolated strains were genotyped using 15 microsatellite markers. The prevalence of T. gondii DNA was found to be 89.6% (n: 43/48) in wild birds. Out of 43 positive samples, a total of 14 strains were genotyped by 15 microsatellite markers. Among them, eight were type II, three were type III and three were mixture of genotypes (two type II/II and one was II/III). These are the first data that showed the presence of T. gondii and types II and III genotypes in wild birds of Turkey. Moreover, Africa 1 was not detected. In addition, cluster analysis showed that T. gondii strains within type II and III lineage have close relation with strains previously isolated from stray cats in İzmir. Further studies are required to isolate more strains from human cases, other intermediate hosts, and water sources to reveal this relation.

On the Weight of the Brain in the Insane, with reference to the Hemispheres, Lobes, Brain-Stem, and Cerebellum

These results are tabulated after weighing 400 brains as follows:—

Toxoplasma and Africa: One Parasite, Two Opposite Population Structures

Exploring the genetic diversity of Toxoplasma gondii is essential for an understanding of its worldwide distribution and the determinants of its evolution. Africa remains one of the least studied areas of the world regarding T. gondii genetic diversity. This review has compiled published data on T. gondii strains from Africa to generate a comprehensive map of their continent-wide geographical distribution. The emerging picture about T. gondii strain distribution in Africa suggests a geographical separation of the parasite populations across the continent. We discuss the potential role of a number of factors in shaping this structure. We finally suggest the next steps towards a better understanding of Toxoplasma epidemiology in Africa in light of the strains circulating on this continent.

First genetic characterization of Toxoplasma gondii in stray cats from Algeria

Toxoplasmosis is a parasitic disease with worldwide distribution and a major public health problem. In Algeria, no data are currently available about genotypes of Toxoplasma gondii isolated from animals or humans. The present study assesses for the first time the seroprevalence of toxoplasmosis in stray cats, and provides molecular characterization of T. gondii strains circulating in this feline population in Algiers, the capital city of Algeria. Sera from 96 stray cats were tested for the presence of antibodies against T. gondii using the modified agglutination test. The seroprevalence was 50% (48/96) using 1:6 as the positivity cut-off. Different organs samples from stray cats, including heart samples, were tested for the presence of Toxoplasma DNA using real-time PCR. T. Gondii DNA was detected in 90.6% (87/96) of hearts. Of these parasitic DNAs, 22 were submitted to genotyping through the analysis of 15 microsatellite markers. The identified genotypes (12 of 22) mainly belonged to the type II lineage.

The first isolation and molecular characterization of Toxoplasma gondii from horses in Serbia

Background

Consumption of undercooked or insufficiently cured meat is a major risk factor for human infection with Toxoplasma gondii. Although horsemeat is typically consumed rare or undercooked, information on the risk of T. gondii from infected horse meat to humans is scarce. Here, we present the results of a study to determine the presence of T. gondii infection in slaughter horses in Serbia, and to attempt to isolate viable parasites.

Methods

The study included horses from all regions of Serbia slaughtered at two abattoirs between June 2013 and June 2015. Blood sera were tested for the presence of specific IgG T. gondii antibodies by the modified agglutination test (MAT), and samples of trypsin-digested heart tissue were bioassayed in mice. Cyst-positive mouse brain homogenates were subjected to DNA extraction and T. gondii strains were genotyped using 15 microsatellite markers (MS).

Results

A total of 105 slaughter horses were sampled. At the 1:6 cut-off 48.6% of the examined horses were seropositive, with the highest titre being 1:400. Viable parasites were isolated from two grade type mares; both parasite isolates (RS-Eq39 and RS-Eq40) were T. gondii type III, and both displayed an increased lethality for mice with successive passages. These are the first cases of isolation of T. gondii from horses in Serbia. When compared with a worldwide collection of 61 type III and type III-like strains, isolate RS-Eq39 showed a combination of MS lengths similar to a strain isolated from a duck in Iran, and isolate RS-Eq40 was identical in all markers to three strains isolated from a goat from Gabon, a sheep from France and a pig from Portugal. Interestingly, the source horses were one seronegative and one weakly seropositive.

Conclusions

The isolation of viable T. gondii parasites from slaughter horses points to horsemeat as a potential source of human infection, but the fact that viable parasites were isolated from horses with only a serological trace of T. gondii infection presents further evidence that serology may not be adequate to assess the risk of toxoplasmosis from horsemeat consumption. Presence of T. gondii type III in Serbia sheds more light into the potential origin of this archetypal lineage in Europe.

Electronic supplementary material

The online version of this article (doi:10.1186/s13071-017-2104-x) contains supplementary material, which is available to authorized users.

Spread rate of lumpy skin disease in the Balkans, 2015-2016

After its introduction in Turkey in November 2013 and subsequent spread in this country, lumpy skin disease (LSD) was first reported in the western Turkey in May 2015. It was observed in cattle in Greece and reported to the World Organization for Animal Health (OIE) in August 2015. From May 2015 to August 2016, 1,092 outbreaks of lumpy skin disease were reported in cattle from western Turkey and eight Balkan countries: Greece, Bulgaria, The Former Yugoslav Republic of Macedonia, Serbia, Kosovo, and Albania. During this period, the median LSD spread rate was 7.3 km/week. The frequency of outbreaks was highly seasonal, with little or no transmission reported during the winter. Also, the skewed distribution of spread rates suggested two distinct underlying epidemiological processes, associating local and distant spread possibly related to vectors and cattle trade movements, respectively.

Toxoplasma gondii survey in cats from two environments of the city of Rio de Janeiro, Brazil by Modified Agglutination Test on sera and filter-paper

Background

Toxoplasma gondii is a protozoan with a worldwide distribution, in warm-blood animals, including humans. Local conditions and environmental disturbances may influence transmission dynamics of a zoonotic agent. This study evaluates the epidemiology of T. gondii based on toxoplasmosis prevalence in two populations of cats living in distinct urbanization conditions in Rio de Janeiro, Brazil.

Methods

Among 372 domestic cats sampled, 265 were from a public shelter located downtown Rio and 107 from a relatively preserved wild environment in a residential area. Sera and eluates from dried blood spots were tested for detection of IgG antibodies against T. gondii by modified agglutination test (MAT).

Results

Antibodies to T. gondii were detected in 32/265 (12.08%) animals from the public shelter and in 4/107 (3.74%) cats from the residential area. Identical results were observed for sera and eluates.

Conclusions

Filter paper provides a reliable accurate alternative storage option when conditions of sample collection and transportation in the field are unfavorable. The significantly lower prevalence in the residential area is discussed in terms of environmental, biological and behavioral features.

Sodium Channel Trafficking

Voltage-gated sodium channels (VGSC) are critical determinants of cellular electrical activity through the control of initiation and propagation of action potential. To ensure this role, these proteins are not consistently delivered to the plasma membrane but undergo drastic quality controls throughout various adaptive processes such as biosynthesis, anterograde and retrograde trafficking, and membrane targeting. In pathological conditions, this quality control could lead to the retention of functional VGSC and is therefore the target of different pharmacological approaches. The present chapter gives an overview of the current understanding of the facets of VGSC life cycle in the context of both cardiac and neuronal cell types.

Phylogeography of Toxoplasma gondii points to a South American origin

Toxoplasma gondii, a protozoan found ubiquitously in mammals and birds, is the etiologic agent of toxoplasmosis, a disease causing substantial public health burden worldwide, including about 200,000 new cases of congenital toxoplasmosis each year. Clinical severity has been shown to vary across geographical regions, with South America exhibiting the highest burden. Unfortunately, the drivers of these heterogeneities are still poorly understood, and the geographical origin and historical spread of the pathogen worldwide are currently uncertain. A worldwide sample of 168 T. gondii isolates gathered in 13 populations was sequenced for five fragments of genes (140 single nucleotide polymorphisms from 3153bp per isolate). Phylogeny based on Maximum likelihood methods with estimation of the time to the most recent common ancestor (TMRCA) and geostatistical analyses were performed for inferring the putative origin of T. gondii. We show that extant strains of the pathogen likely evolved from a South American ancestor, around 1.5 million years ago, and reconstruct the subsequent spread of the pathogen worldwide. This emergence is much more recent than the appearance of ancestral T. gondii, believed to have taken place about 11 My ago, and follows the arrival of felids in this part of the world. We posit that an ancestral lineage of T. gondii likely arrived in South America with felids and that the evolution of oral infectivity through carnivorism and the radiation of felids in this region enabled a new strain to outcompete the ancestral lineage and undergo a pandemic radiation.

Patterns and Drivers of Egg Pigment Intensity and Colour Diversity in the Ocean: A Meta-Analysis of Phylum Echinodermata

Egg pigmentation is proposed to serve numerous ecological, physiological, and adaptive functions in egg-laying animals. Despite the predominance and taxonomic diversity of egg layers, syntheses reviewing the putative functions and drivers of egg pigmentation have been relatively narrow in scope, centring almost exclusively on birds. Nonvertebrate and aquatic species are essentially overlooked, yet many of them produce maternally provisioned eggs in strikingly varied colours, from pale yellow to bright red or green. We explore the ways in which these colour patterns correlate with behavioural, morphological, geographic and phylogenetic variables in extant classes of Echinodermata, a phylum that has close phylogenetic ties with chordates and representatives in nearly all marine environments. Results of multivariate analyses show that intensely pigmented eggs are characteristic of pelagic or external development whereas pale eggs are commonly brooded internally. Of the five egg colours catalogued, orange and yellow are the most common. Yellow eggs are a primitive character, associated with all types of development (predominant in internal brooders), whereas green eggs are always pelagic, occur in the most derived orders of each class and are restricted to the Indo-Pacific Ocean. Orange eggs are geographically ubiquitous and may represent a 'universal' egg pigment that functions well under a diversity of environmental conditions. Finally, green occurs chiefly in the classes Holothuroidea and Ophiuroidea, orange in Asteroidea, yellow in Echinoidea, and brown in Holothuroidea. By examining an unprecedented combination of egg colours/intensities and reproductive strategies, this phylum-wide study sheds new light on the role and drivers of egg pigmentation, drawing parallels with theories developed from the study of more derived vertebrate taxa. The primary use of pigments (of any colour) to protect externally developing eggs from oxidative damage and predation is supported by the comparatively pale colour of equally large, internally brooded eggs. Secondarily, geographic location drives the evolution of egg colour diversity, presumably through the selection of better-adapted, more costly pigments in response to ecological pressure.

[Prevalence of asthma consultations in general practice]

INTRODUCTION

Few data from primary care settings are available about asthma prevalence. The aim of this study was to evaluate the prevalence of asthma consultations in general practice, and to describe their characteristics.

METHODS

This was a multicenter, cross-sectional national study, conducted in general practice. Investigators were 54 interns from 27 medical schools. Between December 2011 and April 2012, they collected and entered variables specific to each consultation over a period of 20 days from a structured electronic health record using the International classification of primary care (ICPC-2) together with data about their trainer(s).

RESULTS

Data were recorded for 20,613 consultations with 45,582 consultation outcomes described. Asthma represented 348 (1.69%) of consultations. The presence of an asthma code was associated with fewer reasons for the consultation, but with more processes of care. Forty-two percent of other consultation results associated with asthma in the same consultation concerned chronic diseases.

CONCLUSION

Our findings suggest that asthma remains underdiagnosed in general practice in France. In order to address this problem, the development of validated diagnostic tools that can be used in general practice settings, and a better access to spirometry, may be directions to explore in future research.

Efficacy of communication skills training on colorectal cancer screening by GPs: a cluster randomised controlled trial

Colorectal cancer (CRC) mass screening has been implemented in France since 2008. Participation rates remain too low. The objective of this study was to test if the implementation of a training course focused on communication skills among general practitioners (GP) would increase the delivery of gaiac faecal occult blood test and CRC screening participation among the target population of each participating GP. A cluster randomised controlled trial was conducted with GP's practice as a cluster unit. GPs from practices in the control group were asked to continue their usual care. GPs of the intervention group received a 4-h educational training, built with previous qualitative data on CRC screening focusing on doctor-patient communication with a follow-up of 7 months for both groups. The primary outcome measure was the patients' participation rate in the target population for each GP. Seventeen GPs (16 practices) in intervention group and 28 GPs (19 practices) in control group participated. The patients' participation rate in the intervention group were 36.7% vs. 24.5% in the control group (P = 0.03). Doctor-patient communication should be developed and appear to be one of the possible targets of improvement patients adherence and participation rate in the target population for CRC mass screening.

Detection of Toxoplasma gondii DNA in horse meat from supermarkets in France and performance evaluation of two serological tests

In France, some cases of severe toxoplasmosis have been linked to the consumption of horse meat that had been imported from the American continent where atypical strains of Toxoplasma gondii are more common than in Europe. Many seroprevalence studies are presented in the literature but risk assessment of T. gondii infection after horse meat consumption is not possible in the absence of validated serological tests and the unknown correlation between detection of antibodies against T. gondii and presence of tissue cysts. We performed magnetic-capture polymerase chain reaction (MC-PCR) to detect T. gondii DNA in 231 horse meat samples purchased in supermarkets in France and evaluated the performance and level of agreement of the modified agglutination test (MAT) and enzyme-linked immunosorbent assay (ELISA) in the meat juices. The serological tests lacked sensitivity, specificity, and agreement between them, and there was no correlation with the presence of T. gondii DNA in horse meat, raising concerns about the reliability of T. gondii seroprevalence data in horses from the literature. T. gondii DNA was detected in 43% of horse meat samples but the absence of strain isolation in mice following inoculation of more than 100 horse meat samples suggests a low distribution of cysts in skeletal muscles and a low risk of T. gondii infection associated with horse meat consumption. However, to avoid any risk of toxoplasmosis, thorough cooking of horse meat is recommended.