Molecular detection of two new putative species of gammaherpesvirus in petaurid possums.

A molecular survey of herpesviruses in Australian native mammals was conducted, spanning 260 individuals from 27 species. Among the herpesviruses detected, a putative new gammaherpesvirus species was detected in the yellow-bellied glider (Petaurus australis), and another in the critically endangered Leadbeater's possum (Gymnobelideus leadbeateri). In addition, the known host range of the putative species macropodid gammaherpesvirus 3 (MaHV-3) is herein extended to the western grey kangaroo (Macropus fuliginosus). These findings expand our understanding of herpesviruses in Australian mammals and may inform biosecurity protocols for captive and translocated populations.

Update on feline alphaherpesvirus-1 seroprevalence in Victorian feral and owned cats.

The seroprevalence of feline alphaherpesvirus-1 (FHV-1) in feral cats in Victoria, Australia, was last assessed in 1981 when serum-virus-neutralising antibodies (VNAb) against FHV-1 were detected in 11% of the sampled population from two Victorian locations. In this current study, VNAb were assessed in serum from feral cats located in Phillip Island, Point Cook and Hattah in the Mallee region in Northern Victoria. In feral cats, the seroprevalence of VNAb to FHV-1 was highest in Point Cook at 24.6% (17/69), followed by Phillip Island at 16.7% (11/66) and Hattah where no feral cats had detectable VNAb to FHV-1 (0/12). In contrast, virus-neutralising antibodies were observed in 84.1% (37/44) of Victorian-owned cats. This higher seroprevalence in owned cats is likely due to the use of FHV-1 vaccines; however, the vaccination history of the cats was not known and the development of neutralising antibodies after infection or vaccination can vary. The results are useful for understanding FHV-1 exposure in feral and owned cats and are important background information in the context of any potential future use of FHV-1-vectored vaccines.

Knowledge of pet-related zoonotic diseases and pet care in Hong Kong, a heavily crowded urban setting.

BACKGROUND: With the rapid expansion of pet animal populations worldwide, pet-related zoonotic diseases are becoming an important issue in public health. Hong Kong (HK), located in southern China, is one of the most crowded urban centres in the world. The population of pets, especially exotic pets, in HK has grown significantly in recent decades, potentially elevating the risk of pet-related zoonotic diseases. However, no studies have been conducted to explore the knowledge of HK public towards pet-related zoonotic diseases and animal husbandry practices. OBJECTIVES: To evaluate the level of awareness among the HK public of pet-related zoonotic diseases and their understanding of proper animal husbandry practices. METHODS: The study was carried out in HK from June-August 2019 using both online and paper versions of a questionnaire. A total of 362 completed questionnaires (74.3% return rate) were collected and the responses analysed. RESULTS: Sixty percent of the participants were current or past pet owners or planned on becoming pet owners in the coming 2 years, irrespective of their income or size of their living space. Among the participants, pet owners (including those who planned pet ownership) had a relatively higher level of awareness of pet-related zoonotic disease. However, the overall awareness of zoonotic diseases among both pet and non-pet owners was low with a knowledge score of <50%. A similar trend was observed for knowledge about proper animal husbandry practices. CONCLUSIONS: This study showed that the HK public was generally not familiar with pet-related zoonotic diseases and proper pet care. These knowledge gaps could potentially increase the risk of disease transmission. Further studies focusing on specific pet species and on people of different social-economic backgrounds are needed to provide future direction of efforts to reduce the risk of pet-related zoonotic diseases and to enhance pet-related animal and human welfare.

Genome Sequences of Two Marsupial Simplex Viruses, Macropodid Alphaherpesviruses 2 and 4.

We present the genome sequences of macropodid alphaherpesviruses 2 and 4, two closely related pathogens of macropods. Both encoded 68 nonredundant open reading frames (ORFs) and share 90.6% genome-wide nucleotide identity. These viruses are associated with fatal outbreaks of disease in multiple marsupial species. These sequences will be important for the development of new diagnostic tools.

Chlamydia psittaci: a suspected cause of reproductive loss in three Victorian horses.

Chlamydia psittaci was detected by PCR in the lung and equine foetal membranes of two aborted equine foetuses and one weak foal from two different studs in Victoria, Australia. The abortions occurred in September 2019 in two mares sharing a paddock northeast of Melbourne. The weak foal was born in October 2019 in a similar geographical region and died soon after birth despite receiving veterinary care. The detection of C. psittaci DNA in the lung and equine foetal membranes of the aborted or weak foals and the absence of any other factors that are commonly associated with abortion or neonatal death suggest that this pathogen may be the cause of the reproductive loss. The detection of C. psittaci in these cases is consistent with the recent detection of C. psittaci in association with equine abortion in New South Wales. These cases in Victoria show that C. psittaci, and the zoonotic risk it poses, should be considered in association with equine reproductive loss in other areas of Australia.

Detection and Differentiation of Two Koala Gammaherpesviruses by Use of High-Resolution Melt (HRM) Analysis Reveals Differences in Viral Prevalence and Clinical Associations in a Large Study of Free-Ranging Koalas.

The iconic koala (Phascolarctos cinereus) is host to two divergent gammaherpesviruses, phascolarctid gammaherpesviruses 1 and 2 (PhaHV-1 and -2), but the clinical significance of the individual viruses is unknown and current diagnostic methods are unsuitable for differentiating between the viruses in large-scale studies. To address this, we modified a pan-herpesvirus nested PCR to incorporate high-resolution melt analysis. We applied this assay in a molecular epidemiological study of 810 koalas from disparate populations across Victoria, Australia, including isolated island populations. Animal and clinical data recorded at sampling were analyzed and compared to infection status. Between populations, the prevalence of PhaHV-1 and -2 varied significantly, ranging from 1% to 55%. Adult and older animals were 5 to 13 times more likely to be positive for PhaHV-1 than juveniles (P < 0.001), whereas PhaHV-2 detection did not change with age, suggesting differences in how these two viruses are acquired over the life of the animal. PhaHV-1 detection was uniquely associated with the detection of koala retrovirus, particularly in females (P = 0.008). Both viruses were significantly associated (P < 0.05) with the presence of genital tract abnormalities (uterine/ovarian cysts and testicular malformation), reduced fertility in females, urinary incontinence, and detection of Chlamydia pecorum, although the strength of these associations varied by sex and virus. Understanding the clinical significance of these viruses and how they interact with other pathogens will inform future management of threatened koala populations.

Eimeria taggarti N. Sp., a Novel Coccidian (Apicomplexa: Eimeriorina) in the Prostate of an Antechinus flavipes.

A novel coccidian species was discovered in the prostate of an Antechinus flavipes (yellow-footed antechinus) in South Australia during the period of postmating male antechinus immunosuppression and mortality. This novel coccidian is unusual because it develops extraintestinally and sporulates endogenously within the prostate gland of its mammalian host. Histological examination of prostatic tissue revealed dense aggregations of spherical and thin-walled tetrasporocystic, dizoic, sporulated coccidian oocysts within tubular lumina, with unsporulated oocysts and gamogonic stages within the cytoplasm of glandular epithelial cells. This coccidian was observed occurring concurrently with dasyurid gammaherpesvirus 1 infection of the antechinus' prostate. Eimeria-specific 18S small-subunit ribosomal (r)DNA polymerase chain reaction amplification was used to obtain a partial 18S rDNA nucleotide sequence from the antechinus coccidian. Bayesian phylogenetic analysis based on 18S rDNA gene sequences revealed that the novel coccidian clusters with reptile-host coccidians, forming an ancestral basal lineage of the eimeriid clade. The species has been named Eimeria taggarti n. sp. on the basis of both sporulated oocyst morphology and molecular characterization. It is suspected that E. taggarti is sexually transmitted via excretion of sporulated oocysts or free sporocysts with prostatic secretions in semen.

Impairment of infectious laryngotracheitis virus replication by deletion of the UL[-1] gene.

Infectious laryngotracheitis virus (ILTV) encodes several unique genes, including a pair of unique nuclear proteins UL0 and UL[-1] that are expressed during replication in cell culture. Although the UL0 gene has been shown to be dispensable for replication, the role of UL[-1] has not been elucidated. In this study a deletion mutant of ILTV lacking the UL[-1] gene was constructed using homologous recombination. The coding sequences of the gene were replaced with the gene for enhanced green fluorescent protein and the cytomegalovirus major immediate early promoter element. The progeny virus carrying the reporter gene was readily identified using fluorescent microscopy, but was unable to propagate in the permissive cells in the absence of wild type ILTV. Even after plaque purification and fluorescent associated cell sorting the recombinant virus deficient in UL[-1] gene could not be successfully isolated. Our findings suggest that the UL[-1] gene has an important role in ILTV replication.

Evidence of widespread natural recombination among field isolates of equine herpesvirus 4 but not among field isolates of equine herpesvirus 1.

Recombination in alphaherpesviruses allows evolution to occur in viruses that have an otherwise stable DNA genome with a low rate of nucleotide substitution. High-throughput sequencing of complete viral genomes has recently allowed natural (field) recombination to be studied in a number of different alphaherpesviruses, however, such studies have not been applied to equine herpesvirus 1 (EHV-1) or equine herpesvirus 4 (EHV-4). These two equine alphaherpesviruses are genetically similar, but differ in their pathogenesis and epidemiology. Both cause economically significant disease in horse populations worldwide. This study used high-throughput sequencing to determine the full genome sequences of EHV-1 and EHV-4 isolates (11 and 14 isolates, respectively) from Australian or New Zealand horses. These sequences were then analysed and examined for evidence of recombination. Evidence of widespread recombination was detected in the genomes of the EHV-4 isolates. Only one potential recombination event was detected in the genomes of the EHV-1 isolates, even when the genomes from an additional 11 international EHV-1 isolates were analysed. The results from this study reveal another fundamental difference between the biology of EHV-1 and EHV-4. The results may also be used to help inform the future safe use of attenuated equine herpesvirus vaccines.

A systematic review of the role of hepatectomy in the management of metastatic renal cell carcinoma.

AIM: This review sought to systematically appraise the literature to establish the role of hepatectomy in treating renal cell carcinoma hepatic metastases. METHOD: Medline and EMBASE were systematically searched for papers reporting survival of patients who underwent hepatectomy for metastatic renal cell carcinoma. RESULTS: Six studies containing 140 patients were included. There were no randomised controlled trials. Perioperative mortality was 4.3%, with reported morbidity between 13 and 30%. Patients with metachronous presentation, and a greater time interval between resection of primary tumour and development of metachronous metastases, appeared to have better survival. There was no difference in survival between patients with solitary and multiple metastases. CONCLUSION: Few patients with hepatic metastases from renal cell carcinoma are suitable for hepatectomy as metastatic disease is usually widespread. Selected patients may experience a survival benefit, but identifying these patients remains difficult.

Assessment of the potential relationship between egg quality and infectious bronchitis virus infection in Australian layer flocks.

OBJECTIVE: This investigation aimed to determine if there was a relationship between the production of eggs with poor internal quality, as measured by poor Haugh units, by Australian layer flocks and the detection of infectious bronchitis virus (IBV) in the hens. Other risk factors including flock size, flock type, flock age, chicken breed and vaccination frequency were also assessed. METHODS: The study group comprised 17 flocks from 14 farms. Data relating to the factors investigated were requested on a regular basis. The Haugh unit data were used to grade eggs as good or poor based on the age and flock at the time of data collection. Cloacal swabs were collected from 20 chickens in each flock approximately every 6 weeks. RESULTS: IBV was detected from a majority of the flocks and in 68% of cases the IBV strain detected was an A-vaccine-related field strain. Three variant strains were detected. Detection of IBV in a flock, the farm type and flock size were identified as potential risk factors for the production of eggs with poor Haugh units. CONCLUSION: IBV is prevalent in Australian layer flocks, but infection was primarily subclinical. The results complement previous reports indicating that there are many potential risk factors for the production of eggs with poor Haugh units.

Detection of a novel gammaherpesvirus in koalas (Phascolarctos cinereus).

A novel gammaherpesvirus was detected in wild koalas (Phascolarctos cinereus) captured at different locations during 2010. Sequence analysis of the DNA polymerase gene revealed that the virus was genetically distinct from all known gammaherpesviruses. This is the first herpesvirus to be definitively identified in the Vombatiforme suborder (koalas and wombats).

Gammaherpesvirus infection in a free-ranging eastern grey kangaroo (Macropus giganteus).

A gammaherpesvirus was detected by polymerase chain reaction (PCR) in ocular, nasal and oropharyngeal swab samples collected from an adult free-ranging male eastern grey kangaroo (Macropus giganteus) with clinical signs of severe respiratory disease. This is the first time a gammaherpesvirus has been detected in a free-ranging macropod in Australia. The nucleotide sequence of a conserved region of the DNA polymerase gene of the detected virus showed a high degree of identity to a gammaherpesvirus recently detected in a zoological collection of eastern grey kangaroos in North America. The detection of this gammaherpesvirus in a free-ranging, native eastern grey kangaroo provides evidence that this species is a natural host.

Application of high-resolution melt curve analysis for classification of infectious bronchitis viruses in field specimens.

OBJECTIVE: A real-time polymerase chain reaction (PCR)/high-resolution melt (HRM) curve analysis protocol was developed in our laboratory to differentiate infectious bronchitis (IB) virus reference strains. In the current study, this method was used to detect and classify IB viruses in field submissions. PROCEDURE: Over an 11-month period samples from 40 cases of suspected IB virus were received and 17 submissions were positive for IB virus by polymerase chain reaction. HRM curve analysis classified each strain as subgroup 1, 2 or 3 strain (12 submissions) or a strain that was unable to be classified (5 submissions). The 3' untranslated region (UTR) and partial S1 gene nucleotide sequences for the 17 IB virus strains were determined and their identity with those of the relative reference strains compared to confirm the classifications generated using the HRM curve analysis. RESULTS: Of the 12 IB field viruses classified as subgroup 1, 2, or 3 using HRM curve analysis, the 3'UTR and S1 gene nucleotide sequences had identities ≥99% with the respective subgroup reference strain. Analysis of the 3' UTR and S1 gene nucleotide sequences for the five IB virus strains that could not be classified indicated that four belonged to one of the subgroups, and one was a potential recombinant strain (between strains from subgroups 2 and 3). A novel recombinant strain was also detected. CONCLUSION: HRM curve analysis can rapidly assign the majority of IB viruses present in field submissions to known subgroups. Importantly, HRM curve analysis also identified variant genotypes that require further investigation.

Comparison of the safety and protective efficacy of vaccination with glycoprotein-G-deficient infectious laryngotracheitis virus delivered via eye-drop, drinking water or aerosol.

Infectious laryngotracheitis virus (ILTV), an alphaherpesvirus, causes respiratory disease in chickens and is commonly controlled by vaccination with conventionally attenuated virus strains. These vaccines have limitations due to residual pathogenicity and reversion to virulence. To avoid these problems and to better control disease, attention has recently turned towards developing a novel vaccine strain that lacks virulence gene(s). Glycoprotein G (gG) is a virulence factor in ILTV. A gG-deficient strain of ILTV has been shown to be less pathogenic than currently available vaccine strains following intratracheal inoculation of specific pathogen free chickens. Intratracheal inoculation of gG-deficient ILTV has also been shown to induce protection against disease following challenge with virulent virus. Intratracheal inoculation, however, is not suitable for large-scale vaccination of commercial poultry flocks. In this study, inoculation of gG-deficient ILTV via eye-drop, drinking water and aerosol were investigated. Aerosol inoculation resulted in undesirably low levels of safety and protective efficacy. Inoculation via eye-drop and drinking water was safe, and the levels of protective efficacy were comparable with intratracheal inoculation. Thus, gG-deficient ILTV appears to have potential for use in large-scale poultry vaccination programmes when administered via eye-drop or in drinking water.

Glycoprotein G is a virulence factor in infectious laryngotracheitis virus.

Infectious laryngotracheitis virus (ILTV; Gallid herpesvirus 1) is an alphaherpesvirus that causes acute respiratory disease in chickens. The role of glycoprotein G (gG) in vitro has been investigated in a number of alphaherpesviruses, but the relevance of gG in vivo in the pathogenicity of ILTV or in other alphaherpesviruses is unknown. In this study, gG-deficient mutants of ILTV were generated and inoculated into specific-pathogen-free chickens to assess the role of gG in pathogenicity. In chickens, gG-deficient ILTV reached a similar titre to wild-type (wt) ILTV but was significantly attenuated with respect to induction of clinical signs, effect on weight gain and bird mortality. In addition, an increased tracheal mucosal thickness, reflecting increased inflammatory cell infiltration at the site of infection, was detected in birds inoculated with gG-deficient ILTV compared with birds inoculated with wt ILTV. The reinsertion of gG into gG-deficient ILTV restored the in vivo phenotype of the mutant to that of wt ILTV. Quantitative PCR analysis of the expression of the genes adjacent to gG demonstrated that they were not affected by the deletion of gG and investigations in vitro confirmed that the phenotype of gG-deficient ILTV was consistent with unaltered expression of these adjacent genes. This is the first reported study to demonstrate definitively that gG is a virulence factor in ILTV and that deletion of gG from this alphaherpesvirus genome causes marked attenuation of the virus in its natural host.

A glycoprotein I- and glycoprotein E-deficient mutant of infectious laryngotracheitis virus exhibits impaired cell-to-cell spread in cultured cells.

In alphaherpesviruses, glycoprotein I (gI) and glycoprotein E (gE) form a heterodimer that functions in cell-to-cell spread of the virus. Generally, alphaherpesvirus mutants that lack these glycoproteins are replication competent in cell culture but show a reduced capacity for cell-to-cell spread and hence smaller plaque sizes. Infectious laryngotracheitis virus (ILTV), or Gallid herpesvirus 1, is an alphaherpesvirus that causes respiratory disease in chickens. The roles of gI and gE in ILTV have not been investigated previously. In this study, a glycoprotein I and glycoprotein E deletion mutant of ILTV (gI/gE-ve ILTV) was generated by replacing the region of the ILTV genome coding for the adjacent gI and gE genes with the gene for enhanced green fluorescent protein (eGFP). This gI/E-ve ILTV was readily propagated in cell culture in the presence of wildtype ILTV (wt ILTV). However, in the absence of wt ILTV the propagation of gI/gE-ve ILTV was severely impaired. Infection of permissive cell cultures with gI/gE-ve ILTV failed to produce plaques but single infected cells could be identified by fluorescence microscopy. This suggests that gI/gE has a more significant role in the cell-to-cell spread of ILTV in vitro than in many other alphaherpesviruses.

Children of parents with mental illness. I: An overview from a nursing perspective.

This paper explores the psychosocial consequences of parental mental illness for child mental health and the implications for mental health nursing. The literature on risk and vulnerability to psychosocial disorder, resilience, child protection, disorder prevention and epidemiological data are reviewed. Based upon a health promotion approach, a model for mental health nursing advocacy for families of adult consumers is proposed as an effective means of preventing disorder in subsequent generations.