Experimental Infection of Sheep using Infective Larvae (L3) harvested from the Faeces of Naturally Infected Swayne’s Hartebeest (Alcelaphus buselaphus swaynei) at Senkele Swayne’s Hartebeest Sanctuary, Ethiopia

Experimental infection of sheep using nematode larvae recovered from the faeces of naturally infected endangered Swayne’s Hartebeest (SHB) was carried out from December/2006 - April/2007 to assess the potential for the inter–species transmission of helminths. Faecal samples were collected from Swayne’s Hartebeest without preservatives and cultivated at room temperature for 21 days. Infective larvae were collected overnight by Baermann’s Method and identified and counted under a microscope. The sample was divided into eight aliquots of 9400 infective larvae and drenched into eight worm-free sheep kept at zero grazing. After 30  days, faecal samples from infected sheep were examined for ova for further 30 days by the Modified McMaster Method. Adult nematodes were recovered from the infected sheep at post mortem examination and distinguished based on position of barbs, shape and length of spicule, position of cervical papillae and mouth parts. The mean eggs per gram of faeces (EPG) from all infected sheep was 9192 ± 1422. Haemonchus placei (86.3%) from abomasums, Oespophagostomum venulosum (13.3%) and Trichuris spp (0.3%) from large intestine were identified. No ova and adult parasite were recovered from the control sheep. The study demonstrated that transmission of helminths between Swayne’s Hartebeest and sheep is experimentally possible. This is the first study conducted on the potential inter-species transmission of parasites between Swayne’s Hartebeest and local sheep and fur ther research is recommended to determine the impact of multiple-species habitat use, on pasture contamination and any associated pathological impact.Key words: Eexperimental infection, helminths, inter-species transmission, local sheep, Swayne’s Hartebees

Genomic analysis of clostridioides difficile recovered from horses in Western Australia

Clostridioides difficile poses an ongoing threat as a cause of gastrointestinal disease in humans and animals. Traditionally considered a human healthcare-related disease, increases in community-associated C. difficile infection (CDI) and growing evidence of inter-species transmission suggest a wider perspective is required for CDI control. In horses, C. difficile is a major cause of diarrhoea and life-threatening colitis. This study aimed to better understand the epidemiology of CDI in Australian horses and provide insights into the relationships between horse, human and environmental strains. A total of 752 faecal samples from 387 Western Australian horses were collected. C. difficile was isolated from 104 (30.9%) horses without gastrointestinal signs and 19 (37.8%) with gastrointestinal signs. Of these, 68 (55.3%) harboured one or more toxigenic strains, including C. difficile PCR ribotypes (RTs) 012 (n = 14), 014/020 (n = 10) and 087 (n = 7), all prominent in human infection. Whole-genome analysis of 45 strains identified a phylogenetic cluster of 10 closely related C. difficile RT 012 strains of equine, human and environmental origin (0–62 SNP differences; average 23), indicating recent shared ancestry. Evidence of possible clonal inter-species transmission or common-source exposure was identified for a subgroup of three horse and one human isolates, highlighting the need for a One Health approach to C. difficile surveillance

Hantavirus maintenance and transmission in reservoir host populations

Hantaviruses are primarily hosted by mammalian species of the orders Rodentia, Eulipotyphla and Chiroptera. Spillover to humans is common, and understanding hantavirus maintenance and transmission in reservoir host populations is important for efforts to curtail human disease. Recent field research challenges traditional phases of virus shedding kinetics derived from laboratory rodent infection experiments. Organ infection sites in non-rodent hosts suggest similar transmission routes to rodents, but require direct assessment. Further advances have also been made in understanding virus persistence (and fadeouts) in fluctuating host populations, as well as occupational, recreational and environmental risk factors associated with spillover to humans. However, despite relevance for both intra-species and inter-species transmission, our understanding of the longevity of hantaviruses in natural environments remains limited.Peer reviewe

Wildlife-livestock interactions and risk areas for cross-species spread of bovine tuberculosis

The transmission of diseases between livestock and wildlife can be a hindrance to effective disease control. Maintenance hosts and contact rates should be explored to further understand the transmission dynamics at the wildlife-livestock interface. Bovine tuberculosis (BTB) has been shown to have wildlife maintenance hosts and has been confirmed as present in the African buffalo (Syncerus caffer) in the Queen Elizabeth National Park (QENP) in Uganda since the 1960s. The first aim of this study was to explore the spatio-temporal spread of cattle illegally grazing within the QENP recorded by the Uganda Wildlife Authority (UWA) rangers in a wildlife crime database. Secondly, we aimed to quantify wildlife-livestock interactions and cattle movements, on the border of QENP, using a longitudinal questionnaire completed by 30 livestock owners. From this database, 426 cattle sightings were recorded within QENP in 8 years. Thirteen (3.1%) of these came within a 300 m–4 week space-time window of a buffalo herd, using the recorded GPS data. Livestock owners reported an average of 1.04 (95% CI 0.97–1.11) sightings of Uganda kob, waterbuck, buffalo or warthog per day over a 3-month period, with a rate of 0.22 (95% CI 0.20–0.25) sightings of buffalo per farmer per day. Reports placed 85.3% of the ungulate sightings and 88.0% of the buffalo sightings as further than 50 m away. Ungulate sightings were more likely to be closer to cattle at the homestead (OR 2.0, 95% CI 1.1–3.6) compared with the grazing area. Each cattle herd mixed with an average of five other cattle herds at both the communal grazing and watering points on a daily basis. Although wildlife and cattle regularly shared grazing and watering areas, they seldom came into contact close enough for aerosol transmission. Between species infection transmission is therefore likely to be by indirect or non-respiratory routes, which is suspected to be an infrequent mechanism of transmission of BTB. Occasional cross-species spillover of infection is possible, and the interaction of multiple wildlife species needs further investigation. Controlling the interface between wildlife and cattle in a situation where eradication is not being considered may have little impact on BTB disease control in cattle

One health, multiple challenges: The inter-species transmission of influenza A virus

Influenza A viruses are amongst the most challenging viruses that threaten both human and animal health. Influenza A viruses are unique in many ways. Firstly, they are unique in the diversity of host species that they infect. This includes waterfowl (the original reservoir), terrestrial and aquatic poultry, swine, humans, horses, dog, cats, whales, seals and several other mammalian species. Secondly, they are unique in their capacity to evolve and adapt, following crossing the species barrier, in order to replicate and spread to other individuals within the new species. Finally, they are unique in the frequency of inter-species transmission events that occur. Indeed, the consequences of novel influenza virus strain in an immunologically naïve population can be devastating. The problems that influenza A viruses present for human and animal health are numerous. For example, influenza A viruses in humans represent a major economic and disease burden, whilst the poultry industry has suffered colossal damage due to repeated outbreaks of highly pathogenic avian influenza viruses. This review aims to provide a comprehensive overview of influenza A viruses by shedding light on interspecies virus transmission and summarising the current knowledge regarding how influenza viruses can adapt to a new host

High level of inter-species transmission of simian foamy virus from non-human primates to humans in Gabon, central Africa

International audienceEach of the pathogenic human retroviruses (HIV-1/2 and HTLV-1) has a non-human primate (NHP) counterpart, and the presence of these retroviruses in humans results from interspecies transmission. The passage of another simian retrovirus, simian foamy virus (SFV), from NHPs to humans has been reported. Here, we evaluated the natural history of SFV in a free-ranging colony of mandrills (CIRMF primate center) and in mandrills living in natura in Gabon (central Africa). We also determined the SFV prevalence in a series of 497 NHP living in different parts of Gabon. Lastly, we investigated the possible transmission of SFVs to humans

Identification and characterization of H2N3 avian influenza virus from backyard poultry and comparison to novel H2N3 swine influenza virus

There are currently 16 identified H subtypes of influenza A; all 16 are known to infect avian species. In 2006 a novel influenza subtype (H2N3) was identified in a swine herd in Missouri. The hemagglutinin (HA) and neuraminidase (NA) genes were found to be avian in origin, raising concern regarding the potential for inter-species transmission of avian viruses to swine and humans. In early 2007, H2N3 influenza virus was isolated from a duck and a chicken from two separate backyard poultry flocks in Ohio. The nearly coincidental isolation of the same subtype in unnatural hosts in the Midwest United States raised the question about the origin of the viruses and the potential for these viruses to adapt to a new host and easily spread to nearby flocks or herds. Therefore, the viruses were further characterized by DNA sequencing and in vivo chicken pathogenicity testing. The virus sequences were compared to those from the 2006 swine isolates. In addition, the avian viruses were tested for cross-reactivity by virus neutralization (VN) and hemagglutination-inhibition (HI) using a panel of H2 reference sera including serum from the Missouri swine virus. Serologic survey on swine herds and poultry flocks in Ohio for H2 virus infection was also conducted to assess virus spreading. Sequence comparisons for the H and N genes demonstrated that the avian viruses were similar, but not identical, to the swine viruses. Accordingly, the avian and swine isolates were also antigenically related as determined by HI and VN assays, suggesting that both avian and swine viruses originated from the same group of H2N3 avian influenza viruses. Although serological surveys using the HI assay on poultry flocks and swine herds in Ohio did not reveal further spreading of H2 virus from the index flocks, continuous surveillance will be necessary. Contemporary H2N3 avian influenza viruses appear to be easily adaptable to poultry and swine, raising concern regarding the potential for inter-species transmission of H2N3 avian virus to humans

Mass Mortality of Adult Male Subantarctic Fur Seals: Are Alien Mice the Culprits?

Background: Mass mortalities of marine mammals due to infectious agents are increasingly reported. However, in contrast to previous die-offs, which were indiscriminate with respect to sex and age, here we report a land-based mass mortality of Subantarctic fur seals with apparent exclusivity to adult males. An infectious agent with a male-predilection is the most plausible explanation for this die-off. Although pathogens with gender-biased transmission and pathologies are unusual, rodents are known sources of male-biased infectious agents and the invasive Mus musculus house mouse, occurs in seal rookeries. Methodology / Principal Findings: Molecular screening for male-biased pathogens in this potential rodent reservoir host revealed the absence of Cardiovirus and Leptospirosis genomes in heart and kidney samples, respectively, but identified a novel Streptococcus species with 30 % prevalence in mouse kidneys. Conclusions / Significance: Inter-species transmission through environmental contamination with this novel bacterium, whose congenerics display male-bias and have links to infirmity in seals and terrestrial mammals (including humans)

Widespread infection with hemotropic mycoplasmas in bats in Spain, including a hemoplasma closely related to 'Candidatus Mycolasma hemohominis'

Molecular analyses of blood samples revealed infection with hemoplasmas in 97% of 31 cave bats captured in three caves in North-Eastern Spain. The characterization of 1250 bp of the 16S rRNA gene in 29 of the positive bats identified two different groups of sequences. Twenty-two Schreibers' bats (Miniopterus schreibersii) and one long-eared bat (Myotis capaccinii) shared one group, composed of seven closely related sequences. These sequences showed an identity of about 97% with "Candidatus Mycoplasma hemohominis" and the phylogenetic branch including bat and human sequences showed a 100% bootstrap value, supporting a close phylogenetic relationship between these hemoplasmas. The second group, representing a potentially novel species, was composed of a single sequence shared by six Schreibers' bats that had 91% identity with the recently reported hemoplasma from little brown bats in North America. Large bat aggregations in roosting caves probably benefits intra and inter-species transmission explaining the high observed prevalence