First detection of Cupriavidus gilardii in a bovine neonatal diarrhea outbreak.

BACKGROUND: Cupriavidus gilardii is an aerobic, gram-negative, motile, glucose-nonfermenting bacillus, first described in 1999. Typically, it exhibits low pathogenicity in humans, causing opportunistic infections primarily in individuals with compromised immune systems. This bacterium has been also found in various environmental sources such as plants and contaminated soils. Notably, there have been no documented cases of C. gilardii infections in animals. CASE PRESENTATION: This case report outlines a bovine neonatal diarrhea outbreak that occurred in Northern Greece, during which C. gilardii was isolated. Faecal samples from 5-day-old calves were collected and transported to the laboratory for further examination. Bacterial culture and next generation sequencing techniques were employed to confirm the presence of this bacterium in the samples. Following the isolation and identification of C. gilardii from the samples, an autogenous vaccine was produced and administered to the cows within the farm. Subsequent to vaccination, a progressive reduction in calf diarrhea and deaths was observed, leading to their eventual complete resolution. To the best of our knowledge, this represents the first documentation of C. gilardii isolation from cases of bovine neonatal diarrhea. CONCLUSION: This case report presents the first isolation case of C. gilardii from animal samples and more specifically from calf faecal samples. It represents an important observation, providing evidence that this opportunistic human pathogen could contribute to clinical symptoms in animals.

First report of canine Astrovirus and Sapovirus in Greece, hosting both asymptomatic and gastroenteritis symptomatic dogs.

BACKGROUND: Astrovirus, Norovirus and Sapovirus are widely distributed viruses in humans and animals worldwide. They have frequently been associated with disease, mainly of gastroenteric nature. In dogs, these viruses have been detected both in symptomatic and asymptomatic animals, mainly of young age. METHODS: In the present epidemiologic study, we investigated the presence of canine Astrovirus (CAstV), canine Norovirus (canine NoV) and canine Sapovirus (Canine SaV) in saliva and stools of 201 domestic dogs originating from throughout Greece, based on two different molecular methods, i.e. conventional and SYBR-Green Real-time RT-PCR. The samples derived from young and adult asymptomatic and symptomatic animals. CAstV was detected in 15/201 (7.5%) and 29/201 (15%) of the examined dogs using conventional RT-PCR and SYBR-Green Real time RT-PCR, respectively. RESULTS: The prevalence of the virus was higher at healthy dogs, with a slight discrepancy of the two methods on the aspect of age (67% young dogs with the method of conventional RT-PCR, versus 52% adult positive dogs with the method of SYBR-Green Real-time RT-PCR). Canine SaV was detected in 52/201 (23%) of the dogs (mainly young and asymptomatic), with the method of SYBR-Green Real-time RT-PCR only, while canine NoV was not detected in any sample with either of the two methods applied. Sequencing of the CAstV positive samples resulted in the acquisition of one CAstV sequence. Phylogenetic analysis confirmed the results, clustering the CAstV sequence with homologous canine hosting sequences from other countries. CONCLUSIONS: CAstV and Canine SaV were proved to circulate in Greek dogs. SYBR-Green Real time RT-PCR showed greater sensitivity in the detection of these viruses. Additionally, we were able to specify the CAstV strain that circulates in Greece, through phylogenetic analysis. To our knowledge, this is the first epidemiological study of CAstV and canine SaV in dogs in Greece, as well as the first time detected in dogs from Greece.

Bartha-K61 vaccine protects nursery pigs against challenge with novel european and asian strains of suid herpesvirus 1.

The present study investigates the pathogenicity of two recently isolated strains of Suid herpesvirus 1 (SuHV1), the Greek strain Hercules and the Chinese strain HeN1, in unvaccinated pigs and in pigs vaccinated with a Bartha-K61 strain. In an experiment performed in negative pressure kiosks (isolators), 45-day old seronegative pigs previously oronasally /intramuscularly vaccinated with the Bartha-K61 vaccine strain, along with unvaccinated controls, were challenged either with the Hercules strain or the HeN1 strain of SuHV1. All animals were observed daily for clinical signs and body temperature and nasal swabs, faeces, blood and bodyweight were collected up to a maximum period of 20 days post-challenge (dpc). The results showed that, in the unvaccinated pigs, HeN1 strain was more virulent than the Hercules strain, with increased mortality, shorter time to death and higher group clinical score (p < 0.05). However, after vaccination with the Bartha-K61 vaccine, there was a drastic reduction in morbidity, mortality, bodyweight loss and virus excretion to almost a similar extent in both strains (p < 0.05). No significant differences were seen among the pigs of the two vaccinated groups compared to unvaccinated unchallenged controls, except a slight elevation in body temperature and in clinical score in the HeN1 vaccinees at 2 and 3 dpc, while bodyweight gain was similar to that of the negative control pigs. Our study showed that despite differences in virulence, the standard vaccination scheme with the Bartha-K61 strain could equally protect nursery pigs against both the European and Chinese strains.

The Complexity of Swine Caliciviruses. A Mini Review on Genomic Diversity, Infection Diagnostics, World Prevalence and Pathogenicity.

Caliciviruses are single stranded RNA viruses, non-enveloped structurally, that are implicated in the non-bacterial gastroenteritis in various mammal species. Particularly in swine, viral gastroenteritis represents a major problem worldwide, responsible for significant economic losses for the pig industry. Among the wide range of viruses that are the proven or suspected etiological agents of gastroenteritis, the pathogenicity of the members of Caliciviridae family is among the less well understood. In this context, the present review presents and discusses the current knowledge of two genera belonging to this family, namely the Norovirus and the Sapovirus, in relation to swine. Aspects such as pathogenicity, clinical evidence, symptoms, epidemiology and worldwide prevalence, genomic diversity, identification tools as well as interchanging hosts are not only reviewed but also critically evaluated. Generally, although often asymptomatic in pigs, the prevalence of those microbes in pig farms exhibits a worldwide substantial increasing trend. It should be mentioned, however, that the factors influencing the symptomatology of these viruses are still far from well established. Interestingly, both these viruses are also characterized by high genetic diversity. These high levels of molecular diversity in Caliciviridae family are more likely a result of recombination rather than evolutionary or selective adaptation via mutational steps. Thus, molecular markers for their detection are mostly based on conserved regions such as the RdRp region. Finally, it should be emphasized that Norovirus and the Sapovirus may also infect other domestic, farm and wild animals, including humans, and therefore their surveillance and clarification role in diseases such as diarrhea is a matter of public health importance as well.

Epidemiology of Astrovirus, Norovirus and Sapovirus in Greek pig farms indicates high prevalence of Mamastrovirus suggesting the potential need for systematic surveillance.

BACKROUND: Astrovirus, Norovirus and Sapovirus exhibit a wide distribution in swine pig herds worldwide. However, the association of porcine Astrovirus (PAstV), porcine Norovirus (PoNoV) and porcine Sapovirus (PoSaV) with disease in pigs remains uncertain. In this study, we investigated the prevalence of PAstV, PoNoV and PoSaV in Greek pig farms using both conventional RT-PCR and SYBR-Green Real-time RT-PCR in an effort to compare the sensitivity of the two methods. We examined 1400 stool samples of asymptomatic pigs originating from 28 swine farms throughout Greece in pools of five. RESULTS: PAstV was detected in all 28 swine farms examined, with an overall prevalence of 267/280 positive pools (95.4%). Porcine Caliciviruses prevalence was found at 36 and 57 out of the 280 examined samples, by the conventional and SYBR-Green Real time RT-PCR, respectively. Sequencing and phylogenetic analysis of the positive samples revealed that the detected PAstV sequences are clustered within PAstV1, 3 and 4 lineages, with PAstV3 being the predominant haplotype (91.2%). Interestingly, sequencing of the Calicivirus positive samples demonstrated the presence of non-target viruses, i.e. Sapovirus, Kobuvirus and Sapelovirus sequences and one sequence highly similar to bat Astrovirus, while no Norovirus sequence was detected. CONCLUSIONS: The high prevalence of PAstV in Greek pig farms poses a necessity for further investigation of the pathogenicity of this virus and its inclusion in surveillance programs in case that it proves to be important. To our knowledge, this is the first epidemiological study of these viruses in pig farms in Greece.