Avian paramyxoviruses and influenza viruses isolated from mallard ducks (Anas platyrhynchos) in New Zealand

A comprehensive study using virological and serological approaches was carried out to determine the status of live healthy mallard ducks (Anas platyrhynchos) in New Zealand for infections with avian paramyxoviruses (APMV) and influenza viruses (AIV). Thirty-three viruses isolated from 321 tracheal and cloacal swabs were characterized as: 6 AIV (two H5N2 and four H4N6), 10 APMV-1 and 17 APMV-4. Of 335 sera samples tested for AIV antibodies, 109 (32.5%) sera were positive by nucleoprotein-blocking ELISA (NP-B-ELISA). Serum samples (315) were examined for antibody to APMV-1, -2, -3, -4, -6, -7, -8, -9 by the haemagglutination inhibition test. The largest number of reactions, with titres up to greater than or equal to 1/64, was to APMV-1 (93.1%), followed by APMV-6 (85.1%), APMV-8 (56%), APMV-4 (51.7%), APMV-7 (47%), APMV-9 (15.9%), APMV-2 (13.3%) and APMV-3 (6.0%). All of the H5N2 isolates of AIV and the APMV-1 isolates from this and earlier New Zealand studies had low pathogenicity indices assessed by the Intravenous Pathogenicity Index (IVPI) with the result 0.00 and Intracerebral Pathogenicity Index (ICPI) with results 0.00-0.16. Partial genomic and antigenic analyses were also consistent with the isolates being non-pathogenic. Phylogenetic analysis of the 10 APMV-1 isolates showed 9 to be most similar to the reference APMV-1 strain D26/76 originally isolated in Japan and also to the Que/66 strain, which was isolated in Australia. The other isolate was very similar to a virus (MC 110/77) obtained from a shelduck in France.

Detection of Influenza type A virus by LightCycler RT-PCR

Using the Roche LightCycler we developed a real-time reverse transcriptase polymerase chain reaction (RT-PCR) assay using the Influenza A LightCycler RT-PCR (FA-LC-RTPCR) for the rapid detection of Influenza A. The assay was used to examine 178 nasopharyngeal aspirate (NPA) samples, from patients with clinically recognised respiratory tract infection, for the presence of Influenza A RNA. The results were then compared to a testing algorithm combining direct immunofluorescent assy (DFA) and a culture augmented DFA (CA-DFA) assay. In total, 76 (43%) specimens were positive and 98 (55%) specimens were negative by both the FA-LC-RTPCR and the DFA and CA-DFA algorithm. In addition, the FA-LC-RTPCR detected a further 4 (2%) positive specimens, which were confirmed by a conventional RT-PCR method. The high level of sensitivity and specificity, combined with the rapid turnaround time for results, makes the LC-RT-PCR assay suitable for the detection of Influenza A in clinical specimens.

A 5 '-nuclease real-time reverse transcriptase-polymerase chain reaction assay for the detection of a broad range of influenza A subtypes, including H5N1

A 5'-nuclease real-time reverse transcriptase-polymerase chain reaction assay was developed for the detection of influenza type A and was validated using a range of influenza A subtypes, including avian strains, and 126 nasopharyngeal aspirate samples. The results show the assay is suitable for screening for influenza A infections, particularly in regions where avian strains may be circulating. (c) 2005 Elsevier Inc. All rights reserved.

Safety of neuraminidase inhibitors for influenza

Neuraminidase inhibitors, oseltamivir and zanamivir, are used for the treatment of, and protection from, influenza. The safety of these compounds has been assessed in systematic reviews. However, the data presented are somewhat limited by the paucity of good quality adverse event data available. The majority of safety outcomes are based on evidence from just one or two randomised controlled trials. The results of the systematic reviews suggest that neuraminidase inhibitors have a reasonable side effect and adverse effect profile if they are to be used to treat or protect patients against a life-threatening disease. However, if these compounds are to be prescribed in situations in which avoidance of inconvenience or minor discomfort is hoped for, then the balance of harms to benefits will be more difficult to judge.

Successful treatment of post-influenza pseudomembranous necrotising bronchial aspergillosis with liposomal amphotericin, inhaled amphotericin B, gamma interferon and GM-CSF

A case of aspergillus tracheobronchitis following influenza A infection in an immunocompetent 35 year old woman is described that required prolonged mechanical ventilation for airways obstruction. Treatment included liposomal amphotericin, inhaled amphotericin, gamma interferon and GM-CSF. Liposomal amphotericin therapy was associated with reversible hepatosplenomegaly. Inhaled corticosteroids with continued antifungal therapy were used for the management of severe recurrent airway obstruction. After a prolonged course of treatment she survived with fixed airways obstruction unresponsive to corticosteroids.

Delivery of multiple CD8 cytotoxic T cell epitopes by DNA vaccination

Development of CD8 alpha beta CTL epitope-based vaccines requires an effective strategy capable of co-delivering large numbers of CTL epitopes, Here we describe a DNA plasmid encoding a polyepitope or polytope protein, which contained multiple contiguous minimal murine CTL epitopes, Mice vaccinated with this plasmid made MHC-restricted CTL responses to each of the epitopes, and protective CTL were demonstrated in recombinant vaccinia virus, influenza virus, and tumor challenge models, CTL responses generated by polytope DNA plasmid vaccination lasted for 1 yr, could be enhanced by co-delivering a gene for granulocyte-macrophage CSF, and appeared to be induced in the absence of CD4 T cell-mediated help, The ability to deliver large numbers of CTL epitopes using relatively small polytope constructs and DNA vaccination technology should find application in the design of human epitope-based CTL vaccines, in particular in vaccines against EBV, HIV, and certain cancers.

The Australian mortality decline: all-cause mortality 1788-1990

This review describes the Australian decline in all-cause mortality, 1788-1990, and compares this with declines in Europe and North America. The period until the 1870s shows characteristic 'crisis mortality', attributable to epidemics of infectious disease. A decline in overall mortality is evident from 1880. A precipitous fall occurs in infant mortality from 1900, similar to that in European countries. Infant mortality continues downward during this century (except during the 1930s), with periods of accelerated decline during the 1940s (antibiotics) and early 1970s. Maternal mortality remains high until a precipitous fall in 1937 coinciding with the arrival of sulphonamide. Excess mortality due to the 1919 influenza epidemic is evident. Artefactual falls in mortality occur in 1930, and for men during the war of 1939-1945. Stagnation in overall mortality decline during the 1930s and 1945-1970 is evident for adult males, and during 1960-1970 for adult females. A decline in mortality is registered in both sexes from 1970, particularly in middle and older age groups, with narrowing of the sex differential. The mortality decline in Australia is broadly similar to those of the United Kingdom and several European countries, although an Australian advantage during last century and the first part of this century may have been due to less industrialisation, lower population density and better nutrition. Australia shows no war-related interruptions in the mortality decline. Australian mortality patterns from 1970 are also similar to those observed in North America and European countries (including the United Kingdom, but excluding Eastern Europe).

Crystallization of a trimeric human T cell leukemia virus type 1 gp21 ectodomain fragment as a chimera with maltose-binding protein

We present a novel protein crystallization strategy, applied to the crystallization of human T cell leukemia virus type 1 (HTLV-1) transmembrane protein gp21 lacking the fusion peptide and the transmembrane domain, as a chimera with the Escherichia coli maltose binding protein (MBP). Crystals could not be obtained with a MBP/gp21 fusion protein in which fusion partners were separated by a flexible linker, but were obtained after connecting the MBP C-terminal alpha-helix to the predicted N-terminal alpha-helical sequence of gp21 via three alanine residues. The gp21 sequences conferred a trimeric structure to the soluble fusion proteins as assessed by sedimentation equilibrium and X-ray diffraction, consistent with the trimeric structures of other retroviral transmembrane proteins. The envelope protein precursor, gp62, is likewise trimeric when expressed in mammalian cells. Our results suggest that MBP may have a general application for the crystallization of proteins containing N-terminal alpha-helical sequences.