Subtyping Blastocystis in pigs and humans revealed unusual avian-specific subtype ST6 in humans in Serbia.

Blastocystis is a common protist colonizing the gastrointestinal tract of humans and various animals. The first subtyping of Blastocystis isolates in pigs and humans in Serbia revealed unusual avian-specific subtype ST6 in humans. In total, 48 pig faecal specimens collected on seven pig farms and 50 human faecal specimens positive to Blastocystis by microscopic examination were selected for the study. Eleven randomly selected PCR-positive pig samples and 10 samples from human patients (with gastrointestinal complaints) were subjected to SSU rDNA sequencing. Three subtypes were identified (ST3, ST5 and ST6) by phylogenetic analysis. ST5 was found in all pig samples; while in human samples, we detected ST3 and ST6. The latter subtype is relatively uncommon in Europe and highly adapted to avian hosts; therefore, the possibility of sporadic zoonotic transmission to human patients should not be ignored.

Multi-Approach Investigation Regarding the West Nile Virus Situation in Hungary, 2018.

The West Nile virus is endemic in multiple European countries and responsible for several epidemics throughout the European region. Its evolution into local or even widespread epidemics is driven by multiple factors from genetic diversification of the virus to environmental conditions. The year of 2018 was characterized by an extraordinary increase in human and animal cases in the Central-Eastern European region, including Hungary. In a collaborative effort, we summarized and analyzed the genetic and serologic data of WNV infections from multiple Hungarian public health institutions, universities, and private organizations. We compared human and veterinary serologic data, along with NS5 and NS3 gene sequence data through 2018. Wild birds were excellent indicator species for WNV circulation in each year. Our efforts resulted in documenting the presence of multiple phylogenetic subclades with Balkans and Western-European progenitor sequences of WNV circulating among human and animal populations in Hungary prior to and during the 2018 epidemic. Supported by our sequence and phylogenetic data, the epidemic of 2018 was not caused by recently introduced WNV strains. Unfortunately, Hungary has no country-wide integrated surveillance system which would enable the analysis of related conditions and provide a comprehensive epidemiological picture. The One Health approach, involving multiple institutions and experts, should be implemented in order to fully understand ecological background factors driving the evolution of future epidemics.

Comparison of Conventional and Molecular Diagnostic Techniques for Detection of Blastocystis sp. in Pig Faeces.

BACKGROUND: Blastocystis is a common protist colonizing the gastrointestinal tract of humans and various animals. Pigs have been suggested to be a reservoir for human Blastocystis infections because of high prevalence of the parasite in these animals and the presence of zoonotic subtypes. Nevertheless, epidemiological data is often misinterpreted due to the lack of standard diagnostic procedures. This study aimed to compare the sensitivity of different diagnostic techniques in detection of Blastocystis sp. in pigs. METHODS: Overall, 48 individual faecal samples were collected from pigs reared in an intensive farming system (Autonomous Province of Vojvodina, Serbia) and were tested by microscopic examination of direct wet mount, in vitro cultivation in modified Jones' medium and conventional PCR for rRNA gene. RESULTS: Xenic in vitro cultivation in Jones' medium showed higher sensitivity than direct wet mount when we compared it with PCR. Namely, the estimated sensitivity of direct wet mount was 46.15%, while the sensitivity of in vitro cultivation was 84.62%. CONCLUSION: Low sensitivity of conventional parasitological compared to molecular methods is proven. Thus, reports on prevalence that rely solely on microscopy of faecal samples (unprocessed or concentrated) are probably underestimating the true prevalence of the parasite.

Body temperature and motion: Evaluation of an online monitoring system in pigs challenged with Porcine Reproductive & Respiratory Syndrome Virus.

Highly contagious and emerging diseases cause significant losses in the pig producing industry worldwide. Rapid and exact acquisition of real-time data, like body temperature and animal movement from the production facilities would enable early disease detection and facilitate adequate response. In this study, carried out within the European Union research project RAPIDIA FIELD, we tested an online monitoring system on pigs experimentally infected with the East European subtype 3 Porcine Reproductive & Respiratory Syndrome Virus (PRRSV) strain Lena. We linked data from different body temperature measurement methods and the real-time movement of the pigs. The results showed a negative correlation between body temperature and movement of the animals. The correlation was similar with both body temperature obtaining methods, rectal and thermal sensing microchip, suggesting some advantages of body temperature measurement with transponders compared with invasive and laborious rectal measuring. We also found a significant difference between motion values before and after the challenge with a virulent PRRSV strain. The decrease in motion values was noticeable before any clinical sign was recorded. Based on our results the online monitoring system could represent a practical tool in registering early warning signs of health status alterations, both in experimental and commercial production settings.

Vaccination of broilers against Newcastle disease in the presence of maternally derived antibodies.

OBJECTIVE: The aim of this study was to evaluate the efficacy of a live attenuated vaccine against Newcastle disease in broilers with different levels of maternally derived antibodies (MDA). While vaccination remains the single most important means for controlling Newcastle disease, presence of MDA may interfere with the vaccination of young birds and decrease the efficacy of the vaccine. MATERIALS AND METHODS: Day-old chicks with variable levels of MDA (negative, low and high) were vaccinated with a live attenuated vaccine against Newcastle disease. Three most commonly used inoculation routes were compared; oculonasal, spray and oral (drinking water). Onset and duration of immunity were measured by serology and challenge with virulent virus. RESULTS: Immune response in vaccinated MDA-positive birds was delayed in comparison with SPF controls. Protection was well established already at 14 days post vaccination in SPF birds while in MDA-positive birds it was 1-2 weeks delayed and was lower throughout the study. Non-vaccinated MDA-positive birds lost passive protection completely at 3-4 weeks of age and were significantly more susceptible to challenge than vaccinated hatch mates at all test points. The protection rate increased in vaccinated birds towards the end of the experiment and reached 70-100 % at the last test points (35-42 days of age). Correlation of haemagglutination inhibition (HI) titre vs. protection rate revealed the importance of cellular and local immunity as most of the vaccinated birds with low HI titre were protected, contrary to their unvaccinated hatch mates with the same HI titre. Oculonasal route seems to provide slightly better protection than the other two routes. CONCLUSIONS AND CLINICAL RELEVANCE: Although immune protection in vaccinated MDA-positive birds may be decreased or delayed, vaccination still provides high protection against ND challenge in comparison with the unvaccinated hatch mates. The degree of interference seems to be proportional to the level of MDA. Vaccination schedules therefore need to be designed according to the immune status of the flock.