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In November 2017, two groups of P. conspicillatus pups from separate locations in Far North Queensland presented with neurological signs consistent with Australian bat lyssavirus (ABLV) infection. These pups (n = 11) died over an 11-day period and were submitted to a government laboratory for testing where ABLV infection was confirmed. Over the next several weeks, additional ABLV cases in flying foxes in Queensland were also detected. Brain tissue from ABLV-infected flying foxes during this period, as well as archived brain tissue, was selected for next-generation sequencing. Phylogenetic analysis suggests that the two groups of pups were each infected from single sources. They were likely exposed while in crèche at night as their dams foraged. This study identifies crèche-age pups at a potentially heightened risk for mass ABLV infection.

The application of variable-number tandem repeats (VNTR) genotyping of Mycobacterium avium subsp. paratuberculosis isolates to assist in investigating incidents of bovine Johne’s disease in a low-prevalence region of Australia is described in the current study. Isolates from a response to detection of bovine Johne’s disease in Queensland were compared with strains from national and international sources. The tandem application of mycobacterial interspersed repetitive unit (MIRU) and multilocus short sequence repeats (MLSSR) genotyping identified 2 strains, 1 that infected cattle on multiple properties with trace-forward histories from a common infected property, and 1 genotypically different strain recovered from a single property. The former strain showed an identical genotype to an isolate from India. Neither strain showed a genotypic link to regions of Australia with a higher prevalence of the disease. Genotyping has indicated incursions from 2 independent sources. This intelligence has informed investigations into potential routes of entry and the soundness of ongoing control measures, and supported strategy and policy decisions regarding management of Mycobacterium avium subsp. paratuberculosis incursions for Queensland.

A five year old Australian stock horse in Monto, Queensland, developed neurological signs and was euthanized after a six day course of illness. Histological examination of the brain and spinal cord revealed moderate to severe, subacute, non-suppurative encephalomyelitis. Sections of spinal cord stained positively in immunohistochemistry with a flavivirus-specific monoclonal antibody. Reverse transcription-polymerase chain reaction assay targeting the envelope gene of flavivirus yielded positive results from brain, spinal cord, cerebrospinal fluid and facial nerve. A flavivirus was isolated from the cerebrum and spinal cord. Nucleotide sequences obtained from amplicons from both tissues and virus isolated in cell culture were compared with those in GenBank, and had 96-98% identity with Murray Valley encephalitis virus. The partial envelope gene sequence of the viral isolate clustered into Genotype 1, and was most closely related to a previous Queensland isolate. This is the first confirmed case of naturally-occurring equine encephalitis attributable to Murray Valley encephalitis virus infection.

Solenopsis invicta Buren (red imported fire ant) are invasive pests that have the capability of major destructive impacts on lifestyle, ecology and economy. Control of this species is dependent, in part, upon ability to estimate the potential spread from newly discovered nests. The potential for spread and the spread characteristics differ between monogyne and polygyne social forms. Prior to this study, differentiation of the two social forms in laboratory test samples commonly used a method involving restriction endonuclease digestion of an amplified Gp-9 fragment. Success of this assay is limited by the quality of DNA, which in the field-collected insects may be affected by temporary storage in unfavourable conditions. Here, we describe an alternative and highly objective assay based upon a high resolution melt technique following preamplification of a significantly shorter Gp-9 fragment than that required for restriction endonuclease digestion. We demonstrate the application of this assay to a S. invicta incursion in Queensland, Australia, using field samples from which DNA may be partially degraded. The reductions in hands-on requirements and overall duration of the assay underpin its suitability for high-throughput testing.

Objective Describe the in-house validation of a previously reported influenza virus type A 5' Taq nuclease assay for detecting equine influenza virus A RNA in nasal swab material. Methods The validation compares the 5' Taq nuclease assay with a gel-based reverse transcription nested polymerase chain reaction (PCR) previously reported by the Irish Equine Centre for detection of H3N8 and H7N7 equine influenza viruses. This test was chosen because it targets a different region of the viral genome to the real-time test, so it is not merely a repeat of the same test in a different format. Moreover, nested PCRs are commonly considered to have similar sensitivity to real-time PCRs and are therefore ideal for evaluation comparisons. Results The sensitivity of the nested PCR was comparable to the 5' Taq nuclease test. Known positive samples and known negative samples reacted with both tests with 100% correlation. Parallel testing of 276 nasal swab samples showed 98% agreement. Conclusion The specificity of the nested amplicons was confirmed by nucleotide sequencing and showed > 99.5% identity with the same region of previously published equine influenza virus A sequences. The results of this work are appropriate validation for the acceptance of the real-time PCR for equine influenza A virus in equine nasal swabs. © 2011 The Authors. Australian Veterinary Journal © 2011 Australian Veterinary Association.

The fire ant Solenopsis invicta is a significant pest that was inadvertently introduced into the southern United States almost a century ago and more recently into California and other regions of the world. An assessment of genetic variation at a diverse set of molecular markers in 2144 fire ant colonies from 75 geographic sites worldwide revealed that at least nine separate introductions of S. invicta have occurred into newly invaded areas and that themain southern U.S. population is probably the source of all but one of these introductions. The sole exception involves a putative serial invasion from the southern United States to California to Taiwan. These results illustrate in stark fashion a severe negative consequence of an increasingly massive and interconnected global trade and travel system.

Ants have evolved very complex societies and are key ecosystem members. Some ants, such as the fire ant Solenopsis invicta, are also major pests. Here, we present a draft genome of S. invicta, assembled from Roche 454 and Illumina sequencing reads obtained from a focal haploidmale and his brothers.Weused comparative genomic methods to obtain insight into the unique features of the S. invicta genome. For example, we found that this genome harbors four adjacent copies of vitellogenin. A phylogenetic analysis revealed that an ancestral vitellogenin gene first underwent a duplication that was followed by possibly independent duplications of each of the daughter vitellogenins. The vitellogenin genes have undergone subfunctionalization with queen- and worker-specific expression, possibly reflecting differential selection acting on the queen andworker castes. Additionally, we identified more than 400 putative olfactory receptors of which at least 297 are intact. This represents the largest repertoire reported so far in insects. S. invicta also harbors an expansion of a specific family of lipid-processing genes, two putative orthologs to the transformer/feminizer sex differentiation gene, a functional DNA methylation system, and a single putative telomerase ortholog. EST data indicate that this S. invicta telomerase ortholog has at least four spliceforms that differ in their use of two sets ofmutually exclusive exons. Someof these and other unique aspects of the fire ant genome are likely linked to the complex social behavior of this species.