World One Health Day 2017 – Research Bites

When: Thursday 2 November 2017 @ 4.00pm – 7.00pm
Where: Geelong Centre for Emerging Infecous Diseases (GCEID) Level 1, HERB Building, Located at the rear of Kitchener House, 285-299 Ryrie Street, Geelong

All welcome at this free event. Register by emailing: gceidadm@deakin.edu.au.

Wish to download the flyer for your own use? click HERE (PDF)

All-Cause Mortality Risk in Australian Women with Impaired Fasting Glucose and Diabetes

Authors: de Abreu, Lelia L. F.; Holloway, Kara L.; Mohebbi, Mohammadreza; Sajjad, Muhammad A.; Kotowicz, Mark A.; Pasco, Julie A.

Source: JOURNAL OF DIABETES RESEARCH,  June 2017

Brief summary of the paper:

Aims. Impaired fasting glucose (IFG) and diabetes are increasing in prevalence worldwide and lead to serious health problems. The aim of this longitudinal study was to investigate the association between impaired fasting glucose or diabetes and mortality over a 10-year period in Australian women.

Methods. This study included 1167 women (ages 20–94 yr) enrolled in the Geelong Osteoporosis Study. Hazard ratios for all-cause mortality in diabetes, IFG, and normoglycaemia were calculated using a Cox proportional hazards model.

Results. Women with diabetes were older and had higher measures of adiposity, LDL cholesterol, and triglycerides compared to the IFG and normoglycaemia groups (all ). Mortality rate was greater in women with diabetes compared to both the IFG and normoglycaemia groups (HR 1.8; 95% CI 1.3–2.7). Mortality was not different in women with IFG compared to those with normoglycaemia (HR 1.0; 95% CI 0.7–1.4).

Conclusions. This study reports an association between diabetes and all-cause mortality. However, no association was detected between IFG and all-cause mortality. We also showed that mortality in Australian women with diabetes continues to be elevated and women with IFG are a valuable target for prevention of premature mortality associated with diabetes.

Prevalence of arthritis according to age, sex and socioeconomic status in six low and middle income countries: analysis of data from the World Health Organization study on global AGEing and adult health (SAGE) Wave 1

Authors: Brennan-Olsen, Sharon L.; Cook, S.; Leech, M. T.; Bowe, S. J.; Kowal, P.; Naidoo, N.; Ackerman, N.; Page, R. S.; Hosking, S. M.; Pasco, J. A.; Mohebbi, M.

Source: BMC MUSCULOSKELETAL DISORDERS, JUN 21 2017

Brief summary of the paper:

Background: In higher income countries, social disadvantage is associated with higher arthritis prevalence; however, less is known about arthritis prevalence or determinants in low to middle income countries (LMICs). We assessed arthritis prevalence by age and sex, and marital status and occupation, as two key parameters of socioeconomic position (SEP), using data from the World Health Organization Study on global AGEing and adult health (SAGE).

Methods: SAGE Wave 1 (2007–10) includes nationally-representative samples of older adults (≥50 yrs), plus smaller samples of adults aged 18-49 yrs., from China, Ghana, India, Mexico, Russia and South Africa (n = 44,747). Arthritis was defined by self-reported healthcare professional diagnosis, and a symptom-based algorithm. Marital status and education were self-reported. Arthritis prevalence data were extracted for each country by 10-year age strata, sex and SEP. Country-specific survey weightings were applied and weighted prevalences calculated. 

Results: Self-reported (lifetime) diagnosed arthritis was reported by 5003 women and 2664 men (19.9% and 14.1%, respectively), whilst 1220 women and 594 men had current symptom-based arthritis (4.8% and 3.1%, respectively). For men, standardised arthritis rates were approximately two- to three-fold greater than for women. The highest rates were observed in Russia: 38% (95% CI 36%–39%) for men, and 17% (95% CI 14%–20%) for women. For both sexes and in all LMICs, arthritis was more prevalent among those with least education, and in separated/divorced/widowed women.

Concludes: High arthritis prevalence in LMICs is concerning and may worsen poverty by impacting the ability to work and fulfil community roles. These findings have implications for national efforts to prioritise arthritis prevention and management, and improve healthcare access in LMICs.

Cohort Profile: Melbourne Atopy Cohort study (MACS)

Authors: Lowe, Adrian J.; Lodge, Caroline J.; Allen, Katrina J.; Abramson, Michael J.; Matheson, Melanie C.; Thomas, Paul S.; Barton, Christopher A.; Bennett, Catherine M.; Erbas, Bircan; Svanes, Cecilie; Wjst, Mathias; Real, Francisco Gomez; Perret, Jennifer L.; Russell, Melissa A.; Southey, Melissa C.; Hopper, John L.; Gurrin, Lyle C.; Axelrad, Christine J.; Hill, David J.; Dharmage, Shyamali C.

Source: INTERNATIONAL JOURNAL OF EPIDEMIOLOGY, 46 (1):25-26G, FEB 2017

Brief summary of the paper: Why was the cohort set up?

The Melbourne Atopy Cohort Study (MACS) is a longitudinal study of a high-risk birth cohort, and their families, that focuses on the natural history, causes and consequences of allergic diseases (eczema, food allergy, asthma and allergic rhinitis). There is evidence that the prevalences of asthma, eczema and allergic rhinitis have risen rapidly since the 1960s and, although the evidence is less robust, there also appears to have been a later increase in the prevalence of food allergy. Australia has one of the highest rates of these diseases in the world. The rapid rise in prevalence suggests that shifts in environmental exposures are important in the induction of these diseases, as genetic influences alone cannot account for such swift changes.

For these reasons we established the MACS in 1990, by recruiting 620 unborn infants (probands) and their family members (1234 parents and 617 siblings). The MACS was originally designed to trial the effect of three infant formulae on the incidence of allergic disease. Before birth, infants were randomized to receive one of three formulae (cows’ milk, soy and a partially hydrolysed whey formula) at cessation or partial cessation of breastfeeding. Further details of this clinical trial are published elsewhere. Although the MACS was commenced as a clinical trial, the data have been subsequently used to address a wide range of questions relating to the natural history of allergic disease and risk factors for these conditions. Specific areas of focus are:

  • oral and environmental risk factors for allergic disease and impaired lung function;
  • use of early life biomarkers, particularly skin prick testing, to identify children at the greatest risk of developing allergic disease;
  • and examination of the natural history and inter- relationships between the manifestations of allergic diseases, including wheeze sub-types.

Continue to read the full paper HERE.

High burden of complicated skin and soft tissue infections in the Indigenous population of Central Australia due to dominant Panton Valentine leucocidin clones ST93-MRSA and CC121-MSSA

Authors: Harch, Susan A. J.; MacMorran, Eleanor; Tong, Steven Y. C.; Holt, Deborah C.; Wilson, Judith; Athan, Eugene; Hewagama, Saliya

Source: BMC INFECTIOUS DISEASES, 17(1):405, JUN 7 2017

Brief summary of the paper:

BACKGROUND: Superficial skin and soft tissue infections (SSTIs) are common among the Indigenous population of the desert regions of Central Australia. However, the overall burden of disease and molecular epidemiology of Staphylococcus aureus complicated SSTIs has yet to be described in this unique population.

METHODS: Alice Springs Hospital (ASH) admission data was interrogated to establish the population incidence of SSTIs. A prospective observational study was conducted on a subset of S. aureus complicated SSTIs (carbuncles and furuncles requiring surgical intervention) presenting during a one month period to further characterize the clinical and molecular epidemiology. High resolution melting analysis was used for clonal complex discrimination. Real-time polymerase chain reaction identifying the lukF component of the Panton Valentine leucocidin (pvl) gene determined pvl status. Clinical and outcome data was obtained from the ASH medical and Northern Territory shared electronic health records.

RESULTS: SSTIs represented 2.1% of ASH admissions during 2014. 82.6% occurred in Indigenous patients (n = 382) with an estimated incidence of 18.9 per 1, 000 people years compared to the non-Indigenous population of 2.9 per 1000, with an incident rate ratio of 6.6 (95% confidence interval 5.1-8.5). Clinical and molecular analysis was performed on 50 isolates from 47 patients. Community-associated methicillin-resistant S. aureus (CA-MRSA) predominated (57% of isolates). The high burden of SSTIs is partly explained by the prevalence of pvl positive strains of S. aureus (90% isolates) for both CA-MRSA and methicillin-susceptible S. aureus (MSSA). ST93-MRSA and CC121-MSSA were the most prevalent clones. SSTIs due to ST93-MRSA were more likely to require further debridement (p = 0.039), however they also more frequently received inactive antimicrobial therapy (p < 0.001).

CONCLUSIONS: ST93-MRSA and CC121-MSSA are the dominant causes of carbuncles and furuncles in Central Australia. Both of these virulent clones harbor pvl but the impact on clinical outcomes remains uncertain. The high prevalence of CA-MRSA supports empiric vancomycin use in this population when antimicrobial therapy is indicated. Prompt surgical intervention remains the cornerstone of treatment.

Are Poultry or Wild Birds the Main Reservoirs for Avian Influenza in Bangladesh?

Authors: Mohammad Mahmudul Hassan, Md. Ahasanul Hoque, Nitish Chandra Debnath, Mat Yamage, and Marcel Klaassen

Source: EcoHealth (available online: 15 June 2017)

Brief summary of the paper: Avian influenza viruses (AIV) are of great socioeconomic and health concern, notably in Southeast Asia where highly pathogenic strains, such as highly pathogenic avian influenza (HPAI) H5N1 and other H5 and H7 AIVs, continue to occur. Wild bird migrants are often implicated in the maintenance and spread of AIV.

However, little systematic surveillance of wild birds has been conducted in Southeast Asia to evaluate whether the prevalence of AIV in wild birds is higher than in other parts of the world where HPAI outbreaks occur less frequently. Across Bangladesh, we randomly sampled a total of 3585 wild and domestic birds to assess the prevalence of AIV and antibodies against AIV and compared these with prevalence levels found in other endemic and non-endemic countries.

Our study showed that both resident and migratory wild birds in Bangladesh do not have a particularly elevated AIV prevalence and AIV sero-prevalence compared to wild birds from regions in the world where H5N1 is not endemic and fewer AIV outbreaks in poultry occur.

Like elsewhere, notably wild birds of the orders Anseriformes were identified as the main wild bird reservoir,although we found exceptionally high sero-prevalence in one representative of the order Passeriformes, the house crow (Corvus splendens), importantly living on offal from live bird markets.

This finding, together with high sero- and viral prevalence levels of AIV in domestic birds, suggests that wild birds are not at the base of the perpetuation of AIV problems in the local poultry sector, but may easily become victim to AIV spill back from poultry into some species of wild birds, potentially assisting in further spread of the virus.

Evolutionary and network analysis of virus sequences from infants infected with an Australian recombinant strain of human parechovirus type 3

Soren A. and Tiffanie N.

Authors: Soren Alexandersen, Tiffanie M. Nelson, Jason Hodge & Julian Druce

Source: Scientific Reports 7, Article number: 3861 (Published online: 20 June 2017) [PDF]

Brief summary of the paper: We present the near complete virus genome sequences with phylogenetic and network analyses of potential transmission networks of a total of 18 Australian cases of human parechovirus type 3 (HPeV3) infection in infants in the period from 2012–2015.

Overall the results support our previous finding that the Australian outbreak strain/lineage is a result of a major recombination event that took place between March 2012 and November 2013 followed by further virus evolution and possibly recombination.

While the nonstructural coding region of unknown provenance appears to evolve significantly both at the nucleotide and amino acid level, the capsid encoding region derived from the Yamagata 2011 lineage of HPeV3 appears to be very stable, particularly at the amino acid level. The phylogenetic and network analyses performed support a temporal evolution from the first Australian recombinant virus sequence from November 2013 to March/April 2014, onto the 2015 outbreak.

The 2015 outbreak samples fall into two separate clusters with a possible common ancestor between March/April 2014 and September 2015, with each cluster further evolving in the period from September to November/December 2015.

Nuclear localization and secretion competence are conserved among henipavirus matrix proteins

Authors: McLinton, Elisabeth C.; Wagstaff, Kylie M.; Lee, Alexander; Moseley, Gregory W.; Marsh, Glenn A.; Wang, Lin-Fa; Jans, David A.; Lieu, Kim G.; Netter, Hans J.

Source: JOURNAL OF GENERAL VIROLOGY, 98 (4):563-576, APR 2017

Brief summary of the paper: Viruses of the genus Henipavirus of the family Paramyxoviridae are zoonotic pathogens, which have emerged in Southeast Asia, Australia and Africa. Nipah virus (NiV) and Hendra virus are highly virulent pathogens transmitted from bats to animals and humans, while the henipavirus Cedar virus seems to be non-pathogenic in infection studies.

The full replication cycle of the Paramyxoviridae occurs in the host cell’s cytoplasm, where viral assembly is orchestrated by the matrix (M) protein. Unexpectedly, the NiV-M protein traffics through the nucleus as an essential step to engage the plasma membrane in preparation for viral budding/release.

Comparative studies were performed to assess whether M protein nuclear localization is a common feature of the henipaviruses, including the recently sequenced (although not yet isolated) Ghanaian bat henipavirus (Kumasi virus, GH-M74a virus) and Mojiang virus. Live-cell confocal microscopy revealed that nuclear translocation of GFP-fused M protein is conserved between henipaviruses in both human- and bat-derived cell lines.

However, the efficiency of M protein nuclear localization and virus-like particle budding competency varied. Additionally, Cedar virus-, Kumasi virus- and Mojiang virus-M proteins were mutated in a bipartite nuclear localization signal, indicating that a key lysine residue is essential for nuclear import, export and induction of budding events, as previously reported for NiV-M.

The results of this study suggest that the M proteins of henipaviruses may utilize a similar nucleocytoplasmic trafficking pathway as an essential step during viral replication in both humans and bats.

Interferon epsilon promotes HIV restriction at multiple steps of viral replication

Authors: Garcia-Minambres, Albert; Eid, Sahar G.; Mangan, Niamh E.; Pade, Corinna; Lim, San S.; Matthews, Antony Y.; de Weerd, Nicole A.; Hertzog, Paul J.; Mak, Johnson

Source: IMMUNOLOGY AND CELL BIOLOGY, 95 (5):478-483, MAY-JUN 2017

Brief summary of the paper: Interferon epsilon (IFNε) is a type I IFN that is expressed constitutively in the female reproductive tract (FRT), and contributes to protection in models of sexually transmitted infections.

Using multiple cell systems, including reporter cell lines and activated peripheral blood lymphocytes (PBLs), we show that recombinant IFNε impairs HIV infection at stage(s) post HIV entry and up to the translation of viral proteins. Consistent with this, IFNε upregulated a number of host cell restriction factors that block HIV at these stages of the replication cycle.

The potency of IFNε induction of these HIV restriction factors was comparable to conventional type I IFNs, namely IFNα and IFNβ. IFNε also significantly reduced the infectivity of progeny virion particles likely by inducing expression of HIV restriction factors, such as IFITM3, which act at that stage of infection. Thus, our data demonstrate that human IFNε suppresses HIV replication at multiple stages of infection.

Setting conservation priorities for migratory networks under uncertainty

Authors: Dhanjal-Adams, Kiran L.; Klaassen, Marcel; Nicol, Sam; Possingham, Hugh P.; Chades, Iadine; Fuller, Richard A.

SourceCONSERVATION BIOLOGY, 31 (3):646-656, JUN 2017

Brief summary of the paper: Conserving migratory species requires protecting connected habitat along the pathways they travel. Despite recent improvements in tracking animal movements, migratory connectivity remains poorly resolved at a population level for the vast majority of species, thus conservation prioritization is hampered.

To address this data limitation, we developed a novel approach to spatial prioritization based on a model of potential connectivity derived from empirical data on species abundance and distance traveled between sites during migration. We applied the approach to migratory shorebirds of the East Asian-Australasian Flyway.

Conservation strategies that prioritized sites based on connectivity and abundance metrics together maintained larger populations of birds than strategies that prioritized sites based only on abundance metrics. The conservation value of a site therefore depended on both its capacity to support migratory animals and its position within the migratory pathway; the loss of crucial sites led to partial or total population collapse.

We suggest that conservation approaches that prioritize sites supporting large populations of migrants should, where possible, also include data on the spatial arrangement of sites.