First detection of anti-Besnoitia spp. specific antibodies in horses and donkeys in Italy

Among Apicomplexa protozoa infecting equids, Besnoitia spp., Toxoplasma gondii and Neospora spp. represent important issues from a sanitary and zootechnical viewpoint. However, only scarce epidemiological data are available on the spread of the infections in horses and donkeys in Europe. Therefore, a serosurvey was planned to estimate the prevalence of these Sarcocystidae species in Italian equids. Serum samples from 268 horses and 18 donkeys raised in Italy were collected and serologically analyzed to detect anti-Besnoitia spp., anti-T. gondii and anti-Neospora spp. antibodies: an approach based on an initial screening by in-house ELISA followed by a confirmatory WB was used. Two horses (0.7%) and four donkeys (22.2%), showed antibodies anti-Besnoitia spp. Ten horses (3.7%) resulted positive to T. gondii and one of these (0.4%) was seropositive also to Neospora spp. This is the first detection of anti-Besnoitia spp. specific antibodies in Italian horses and donkeys. The study confirmed the circulation of Besnoitia spp. among equids in Europe. Low prevalence of T. gondii and Neospora spp. in horses raised in Italy was reported. Nevertheless, it is noteworthy to consider that consumption of horse meat could represent a source for human toxoplasmosis.     

Prevalence of anti-Toxoplasma gondii antibody in domestic horses in Japan

The present study is the first report that investigated the seroprevalence of Toxoplasma gondii infection in domestic horses in various prefectures of Japan and analyzed risk factors for seropositivity. We performed a latex agglutination test for riding/racing horses from 11 prefectures in Japan (783 samples) and 4 groups of Japanese native horses (254 samples). The total seroprevalence of anti-T. gondii antibody in horses examined in this study was 4.24% (44/1037). As for riding/racing horses, we did not find a statistically different T. gondii seroprevalence between sampling prefectures. In contrast, seroprevalence of T. gondii in older horses (> 21 years) was significantly higher than that in younger horses (< 5 years and 11–15 years). There was no significant difference in T. gondii seroprevalence between riding/racing horses and Japanese native horses. Logistical regression analysis revealed that age, but not sex and usage, is a significant risk factor of T. gondii infection for domestic horses in Japan. These findings suggest that domesticated horses in Japan can be horizontally infected with T. gondii by ingestion of food or water contaminated with oocysts.     

Epidemiological studies on caprine arthritis-encephalitis virus infection in Jordan

To investigate the seroprevalence of, and risk factors for, caprine arthritis-encephalitis virus (CAEV) infection in different breeds of goats in Jordan, sera from 1100 goats from three different geographical regions in Jordan were analyzed. Prevalence of antibodies to CAEV was determined using a competitive ELISA test. A semi-structured questionnaire was used to collect information on herd health and management. Questionnaire data were tested in a multivariable logistic regression model to elucidate risk factors associated with CAEV seropositivity. In addition, the incidence of CAEV antibodies was investigated in six goat herds located in the northern part of Jordan. Out of the 69 goat herds investigated, 16 (23.2%) had antibodies against CAEV. Individual goat true seroprevalence to CAEV was 8.9%. The highest CAEV seroprevalence was observed in goats older than 3-years and younger than 6-years of age. The seroprevalence of CAEV in goats was significantly higher (P < 0.05) in the northern part of Jordan than that in central or southern parts of Jordan. The multivariable logistic regression model identified large herd size (OD = 2.0; 95% CI: 1.1, 2.7), addition of new animals to the herd (OD = 1.3; 95% CI: 0.3, 1.6) and contact with other goat herds (OD = 1.1; 95% CI: 0.9, 2.0) as risk factors for CAEV seropositivity. The incidence of CAEV seropositivity in the six herds monitored in the northern part of Jordan ranged from 2.4 to 5.3%.     

Prevalence and Associated Risk Factors of Toxocara vitulorum Infections in Buffalo and Cattle Calves in Three Provinces of Central Cambodia

The prevalence and associated risk factors of Toxocara vitulorum infection in buffalo and cattle calves was studied in 3 provinces in central Cambodia. Fecal samples were collected from 517 calves between the age of 1-15 weeks and processed for nematode egg counts by a modified McMaster method. A total of 64 calves were found to excrete T. vitulorum eggs in their feces (12.4%; 95% exact CI: 9.7-15.5). The mean fecal egg count was 2,798 EPG (SD=16,351; range=0-224,400). A multivariable generalized linear mixed model showed higher odds of T. vitulorum infection for buffalo versus cattle, for animals aged 4-8 weeks versus younger and older ones, and for animals with strongyle infection. There was no association with fecal consistency. Farmers should be aware of the potential impact of T. vitulorum, and treat their calves at the age of 2-3 weeks with anthelmintics such as benzimidazoles or pyrantel.     

Detection of Fusarium wilt pathogens of Psidium guajava L. in soil using culture independent PCR (ciPCR)

Traditional culturing methods take a long time for identification of pathogenic isolates. A protocol has been developed for the detection of Fusarium from soil samples in the early stage of infection. Seventeen soil samples from different locations were collected before the onset of rains to find out the presence of Fusarium spp. population present in the soil of guava orchards and to correlate its presence with incidence of wilt. A PCR based method was developed for the molecular characterization of Fusarium using Fusarium spp. specific primer. DNA extracted by this method was free from protein and other contaminations and the yield was sufficient for PCR amplification. The primer developed in this study was amplifying ∼230 bp in all infected samples while not in healthy soil. The specificity and sensitivity of primer were tested on several Fusarium spp. and found that this primer was amplifying 10⁻⁶ dilution of the fungal DNA. The present study facilitates the rapid detection of Fusarium spp. from infected soil samples of guava collected from different agroclimatic regions in India. A rapid detection method for pathogens and a diagnostic assay for disease would facilitate an early detection of pathogen and lead to more effective control strategies.     

Seroprevalence of Toxoplasma gondii Among Primary School Children in Shandong Province,China

Although Toxoplasma gondii infection in primary school children has been investigated in many countries, limited surveys have been available in primary school children in China. In the present study, we report the seroprevalence of T. gondii infection in primary school children in Shandong province, China. Sera from 6,000 primary school children were evaluated for T. gondii antibodies with ELISA. The overall seroprevalence of T. gondii infection was 16.0% (961/6,000), of which 14.5% (870/6,000) were positive for anti-T. gondii IgG antibodies, 3.4% (206/6,000) positive for IgM, and 1.9% (115/6,000) were positive for both IgG and IgM. The results of the present investigation indicated a high seroprevalence of T. gondii infection in primary school children in Shandong province, China. Therefore, effective measures should be taken to prevent and control T. gondii infection in primary school children in this province. To the best of our knowledge, this is the first report of T. gondii seroprevalence in primary school children in Shandong province, China.     

Seroprevalence of Babesia caballi and Theileria equi in the Swiss horse population

In Switzerland, the prevalence and incidence of equine piroplasma parasite (EPP) infections are unknown. In order to obtain a first insight into the prevalence, a representative sample of 689 sera of horses from Switzerland was serologically tested for the presence of antibodies directed against T. equi and B. caballi using the Indirect Fluorescence Antibody Test (IFAT). A total of 50 (7.3%) horses were seropositive for EPP: overall, the seroprevalence of T. equi was significantly higher than that of B. caballi (p = 0.002). The seropositivities in indigenous horses (animals bred and raised in Switzerland) and in imported horses were 4.8% (11/230) and 8.5% (39/459), respectively. Unlike in indigenous horses, where no significant difference in seroprevalences could be observed between the two parasite species, the seroprevalence of T. equi was significantly higher (p < 0.001) than that of B. caballi in imported horses. Horses imported from France, Spain and Portugal exhibited a significantly higher seroprevalence, and horses imported from Germany a significantly lower seroprevalence of EPP compared to indigenous horses. There were no associations between sex, age, weight loss, surgery or blood transfusions with T. equi and B. caballi seroprevalences.The overall seroprevalence of 7.3% clearly shows that infection with EPP is a threat to the health of the horses in Switzerland. With the presumed expansion of permissive tick vectors, EPP infections will potentially increase in importance in the future. Therefore, continuous monitoring is mandatory.     

Analysis of somatic and salivary gland antigens of third stage larvae of Rhinoestrus spp. (Diptera, Oestridae)

Larvae of Rhinoestrus spp. (Diptera, Oestridae) infect nasal and sinus cavities of horses, causing a nasal myiasis characterized by severe respiratory distress. Presently, the diagnosis of horse nasal botfly relies on the observation of clinical signs, on the post mortem retrieval of larvae or on molecular assays performed using pharyngeal swabs. The present study was carried out to characterize larval somatic proteins and salivary glands of Rhinoestrus spp. in a preliminary assessment towards the immunodiagnosis of equine rhinoestrosis. Out of the 212 necropsied horses 13 were positive for the presence of Rhinoestrus spp. larvae. The analysis of the sera from the infected animals by Western blotting assay showed the presence of a specific host humoral immune response against Rhinoestrus spp. larvae and proved that the salivary glands are the major immunogens in horse nasal botflies.     

Reproduction and nutritional stress are risk factors for Hendra virus infection in little red flying foxes (Pteropus scapulatus)

Hendra virus (HeV) is a lethal paramyxovirus which emerged in humans in 1994. Poor understanding of HeV dynamics in Pteropus spp. (flying fox or fruit bat) reservoir hosts has limited our ability to determine factors driving its emergence. We initiated a longitudinal field study of HeV in little red flying foxes (LRFF; Pteropus scapulatus) and examined individual and population risk factors for infection, to determine probable modes of intraspecific transmission. We also investigated whether seasonal changes in host behaviour, physiology and demography affect host-pathogen dynamics. Data showed that pregnant and lactating females had significantly higher risk of infection, which may explain previously observed temporal associations between HeV outbreaks and flying fox birthing periods. Age-specific seroprevalence curves generated from field data imply that HeV is transmitted horizontally via faeces, urine or saliva. Rapidly declining seroprevalence between two field seasons suggests that immunity wanes faster in LRFF than in other flying fox species, and highlights the potentially critical role of this species in interspecific viral persistence. The highest seroprevalence was observed when animals showed evidence of nutritional stress, suggesting that environmental processes that alter flying fox food sources, such as habitat loss and climate change, may increase HeV infection and transmission. These insights into the ecology of HeV in flying fox populations suggest causal links between anthropogenic environmental change and HeV emergence.     

Molecular Detection and Seroprevalence of Babesia microti among Stock Farmers in Khutul City,Selenge Province,Mongolia

Babesiosis is an emerging tick-borne disease in humans worldwide; however, little is known about the frequency of infection or prevalence of this disease in other parts of the world, excluding North America. In this study, we aimed to investigate Babesia microti infection frequency in a human population in Mongolia. One hundred blood samples were collected from stock farmers living in Khutul city of Selenge province, Mongolia. The sera and DNA from blood samples were evaluated for the presence of B. microti infection by using indirect fluorescent antibody (IFA) tests and PCR. The positive detection rates obtained using the IFA tests and PCR assays were 7% and 3%, respectively. This study is the first to detect of B. microti infections based on antibody seroprevalence or PCR assays for the presence of B. microti DNA in a Mongolian population.     

Serologic Survey of Toxoplasmosis in Seoul and Jeju-do, and a Brief Review of Its Seroprevalence in Korea

Knowledge of the prevalence of human Toxoplasma gondii infection is required in the Republic of Korea. In this study, we surveyed the seroprevalence of T. gondii infection and analyzed the risk factors associated with seropositivity among residents in 2 administrative districts; Seoul and the island of Jeju-do, which have contrasting epidemiologic characteristics. Sera and blood collected from 2,150 residents (1,114 in Seoul and 1,036 in Jeju-do) were checked for IgG antibody titers using ELISA and for the T. gondii B1 gene using PCR. In addition, participants completed a questionnaire that solicited information on gender, age, occupation, eating habits, history of contact with animals, and travel abroad. The T. gondii B1 gene was not detected in all residents examined. However, ELISA showed 8.0% (89 of 1,114 sera) positive for IgG antibodies against T. gondii in Seoul and 11.3% (117 of 1,036 sera) in Jeju-do. In both districts, the positive rates were higher in males than in females, and those 40-79 years of age showed higher rates than other ages. In Seoul, residents older than 70 years of age showed the highest positive rate, 14.9%, whereas in Jeju-do the highest prevalence, 15.6%, was in those in their sixties. The higher seropositive rate in Jeju-do than in Seoul may be related to eating habits and occupations. The present results and a review of related literature are indicative of an increased seroprevalence of T. gondii in Korea in recent years.     

The impact of climate change on the geographical distribution of two vectors of Chagas disease: implications for the force of infection

Chagas disease, caused by the parasite Trypanosoma cruzi, is the most important vector-borne disease in Latin America. The vectors are insects belonging to the Triatominae (Hemiptera, Reduviidae), and are widely distributed in the Americas. Here, we assess the implications of climatic projections for 2050 on the geographical footprint of two of the main Chagas disease vectors: Rhodnius prolixus (tropical species) and Triatoma infestans (temperate species). We estimated the epidemiological implications of current to future transitions in the climatic niche in terms of changes in the force of infection (FOI) on the rural population of two countries: Venezuela (tropical) and Argentina (temperate). The climatic projections for 2050 showed heterogeneous impact on the climatic niches of both vector species, with a decreasing trend of suitability of areas that are currently at high-to-moderate transmission risk. Consequently, climatic projections affected differently the FOI for Chagas disease in Venezuela and Argentina. Despite the heterogeneous results, our main conclusions point out a decreasing trend in the number of new cases of Tr. cruzi human infections per year between current and future conditions using a climatic niche approach.     

A Cross-Sectional Study on Intestinal Parasitic Infections in Rural Communities,Northeast Thailand

Despite the existence of effective anthelmintics, parasitic infections remain a major public health problem in Southeast Asia, including Thailand. In rural communities, continuing infection is often reinforced by dietary habits that have a strong cultural basis and by poor personal hygiene and sanitation. This study presents a survey of the prevalence of intestinal parasitic infections among the people in rural Thailand. The community-based cross-sectional study was conducted in villages in Khon Kaen Province, northeastern Thailand, from March to August 2013. A total of 253 stool samples from 102 males and 140 females, aged 2-80 years, were prepared using formalin-ethyl acetate concentration methods and examined using light microscopy. Ninety-four individuals (37.2%) were infected with 1 or more parasite species. Presence of parasitic infection was significantly correlated with gender (P=0.001); nearly half of males in this survey (49.0%) were infected. Older people had a higher prevalence than younger members of the population. The most common parasite found was Opisthorchis viverrini (26.9%), followed by Strongyloides stercoralis (9.5%), Taenia spp. (1.6%), echinostomes (0.4%), and hookworms (0.4%). The prevalence of intestinal protozoa was Blastocystis hominis 1.6%, Entamoeba histolytica 0.8%, Entamoeba coli 0.8%, Balantidium coli 0.4%, Iodamoeba bütschlii 0.4%, and Sarcocystis hominis 0.4%. Co-infections of various helminths and protozoa were present in 15.9% of the people. The present results show that the prevalence of parasitic infections in this region is still high. Proactive education about dietary habits, personal hygiene, and sanitation should be provided to the people in this community to reduce the prevalence of intestinal parasite infections. Moreover, development of policies and programs to control parasites is needed.     

Fecal and Molecular Survey of Neospora caninum in Farm and Household Dogs in Mashhad Area, Khorasan Province, Iran

Neospora caninum is an important cause of abortion in dairy cattle worldwide. Dog is the definitive host for N. caninum and can infect dairy cattle. The aim of this study is to determine the prevalence of Neospora oocysts in feces of dogs from dairy farms. A total of 174 fecal samples was collected from 89 farm dogs and 85 household dogs during 2006 and 2008. Fecal samples of dogs were microscopically examined for detecting Hammondia Neospora-like oocysts (HNLO) by Mini Parasep®SF fecal parasite concentrator. HNLO were microscopically detected in 4 fecal samples (2.2%). The fecal samples with HNLO were examined by N. caninum-specific PCR. Two of the samples were positive for N. caninum. The 2 positive fecal samples were selected for inoculation to calves. Two inoculated calves were seronegative by ELISA for 4 months post-infection. This is the first report of finding N. caninum DNA in feces of farm dogs in Mashhad area, Iran.     

Seroprevalence of Toxoplasma gondii Infection among HIV/AIDS Patients in Eastern China

Toxoplasmosis, a neglected tropical disease caused by the protozoan parasite Toxoplasma gondii, occurs throughout the world. Human T. gondii infection is asymptomatic in 80% of the population; however, the infection is life-threatening and causes substantial neurologic damage in immunocompromised patients such as HIV-infected persons. The major purpose of this study was to investigate the seroprevalence of T. gondii infection in subjects infected with HIV/AIDS in eastern China. Our findings showed 9.7% prevalence of anti-T. gondii IgG antibody in HIV/AIDS patients, which was higher than in intravenous drug users (2.2%) and healthy controls (4.7%), while no significant difference was observed in the seroprevalence of anti-Toxoplasma IgM antibody among all participants (P>0.05). Among all HIV/AIDS patients, 15 men (7.7%) and 10 women (15.9%) were positive for anti-T. gondii IgG antibody; however, no significant difference was detected in the seroprevalence of anti-Toxoplasma IgG antibody between males and females. The frequency of anti-Toxoplasma IgG antibody was 8.0%, 13.2%, 5.5%, and 0% in patients with normal immune function (CD4⁺ T-lymphocyte count ≥500 cells/ml), immunocompromised patients (cell count ≥200 and <500 cells/ml), severely immunocompromised patients (cell count ≥50 and <200 cells/ml), and advanced AIDS patients, respectively (cell count <50 cells/ml), while only 3 immunocompromised patients were positive for anti-T. gondii IgM antibody. The results indicate a high seroprevalence of T. gondii infection in HIV/AIDS patients in eastern China, and a preventive therapy for toxoplasmosis may be given to HIV/AIDS patients based on CD4⁺ T lymphocyte count.     

Relative importance of management, meteorological and environmental factors in the spatial distribution of Fasciola hepatica in dairy cattle in a temperate climate zone

Fasciola hepatica, a trematode parasite with a worldwide distribution, is the cause of important production losses in the dairy industry. Diagnosis is hampered by the fact that the infection is mostly subclinical. To increase awareness and develop regionally adapted control methods, knowledge on the spatial distribution of economically important infection levels is needed. Previous studies modelling the spatial distribution of F. hepatica are mostly based on single cross-sectional samplings and have focussed on climatic and environmental factors, often ignoring management factors. This study investigated the associations between management, climatic and environmental factors affecting the spatial distribution of infection with F. hepatica in dairy herds in a temperate climate zone (Flanders, Belgium) over three consecutive years. A bulk-tank milk antibody ELISA was used to measure F. hepatica infection levels in a random sample of 1762 dairy herds in the autumns of 2006, 2007 and 2008. The infection levels were included in a Geographic Information System together with meteorological, environmental and management parameters. Logistic regression models were used to determine associations between possible risk factors and infection levels. The prevalence and spatial distribution of F. hepatica was relatively stable, with small interannual differences in prevalence and location of clusters. The logistic regression model based on both management and climatic/environmental factors included the factors: annual rainfall, mowing of pastures, proportion of grazed grass in the diet and length of grazing season as significant predictors and described the spatial distribution of F. hepatica better than the model based on climatic/environmental factors only (annual rainfall, elevation and slope, soil type), with an Area Under the Curve of the Receiver Operating Characteristic of 0.68 compared with 0.62. The results indicate that in temperate climate zones without large climatic and environmental variation, management factors affect the spatial distribution of F. hepatica, and should be included in future spatial distribution models.     

Toxoplasmosis seroprevalence in urban rodents: a survey in Niamey,Niger

A serological survey of Toxoplasma gondii was conducted on 766 domestic and peridomestic rodents from 46 trapping sites throughout the city of Niamey, Niger. A low seroprevalence was found over the whole town with only 1.96% of the rodents found seropositive. However, differences between species were important, ranging from less than 2% in truly commensal Mastomys natalensis, Rattus rattus and Mus musculus, while garden-associated Arvicanthis niloticus displayed 9.1% of seropositive individuals. This is in line with previous studies on tropical rodents - that we reviewed here - which altogether show that Toxoplasma seroprevalence in rodent is highly variable, depending on many factors such as locality and/or species. Moreover, although we were not able to decipher statistically between habitat or species effect, such a contrast between Nile grass rats and the other rodent species points towards a potentially important role of environmental toxoplasmic infection. This would deserve to be further scrutinised since intra-city irrigated cultures are extending in Niamey, thus potentially increasing Toxoplasma circulation in this yet semi-arid region. As far as we are aware of, our study is one of the rare surveys of its kind performed in Sub-Saharan Africa and the first one ever conducted in the Sahel.     

Prevalence of Zoonotic Trematode Metacercariae in Freshwater Fish from Gangwon-do,Korea

The infection status of zoonotic trematode metacercariae was investigated in a total of 2,293 freshwater fish collected from 11 rivers or streams in 9 administrative regions of Gangwon-do, Korea for 5 years (2009-2013). All fish were collected by netting methods and examined using the artificial digestion methods. Clonorchis sinensis metacercariae were detected in 4 fish species, i.e., Pungtungia herzi, Squalidus japonicus coreanus, Acheilognathus rhombeus, and Ladislabia taczanowskii, from only Hantangang in Cheorwon-gun. Metagonimus spp. metacercariae were found in 1,154 (50.3%) fish and their average number per infected fish was 55.8. Among the positive fish species, especially Tribolodon hakonensis from Namdaecheon in Yangyang-gun and Plecoglossus altivelis from Osipcheon in Samcheok-si were most heavily infected. Centrocestus armatus metacercariae were detected in 611 (26.7%) fish and the average metacercarial burden per infected fish was 1,032. Two chub species, Zacco platypus and Zacco temminckii were highly and heavily infected with C. armatus metacercariae in almost all regions surveyed. Echinostoma spp. metacercariae were also found in 24 fish from a few localities, but their numbers per fish infected were very low. From the above results, it is confirmed that the metacercariae of intestinal flukes, especially Metagonimus spp. and C. armatus, were heavily infected, while C. sinensis metacercariae were rarely found in fish from Gangwon-do, Korea.