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Geelong West, Australia

Samaan G.,National Center for Epidemiology and Population Health | Hendrawati F.,Disease Investigation Center | Taylor T.,Australian Animal Health Laboratory | Pitona T.,Disease Investigation Center | And 4 more authors.
Bulletin of the World Health Organization | Year: 2012

Problem The World Health Organization (WHO) developed a guideline with 10 control measures to reduce transmission of A(H5N1) avian influenza virus in markets in low-resource settings. The practical aspects of guide implementation have never been described. Approach WHO's guideline was implemented in two Indonesian markets in the city of Makassar to try to reduce transmission of the A(H5N1) virus. The guideline was operationalized using a participatory approach to introduce a combination of infrastructural and behavioural changes. Local setting Avian influenza is endemic in birds in Makassar. Two of the city's 22 dilapidated, poorly-run bird markets were chosen for the study. Before the intervention, neither market was following any of WHO's 10 recommended control measures except for batch processing. Relevant changes Market stakeholders' knowledge about the avian influenza A(H5N1) virus improved after the interventions. WHO guideline recommendations for visual inspection, cleaning and poultry-holding practices, as well as infrastructural requirements for zoning and for water supply and utilities, began to conform to the WHO guideline. Low-maintenance solutions such as installation of wastewater treatment systems and economic incentives such as composting were well received and appropriate for the low-resource setting. Lessons learnt Combining infrastructural changes with behaviour change interventions was critical to guideline implementation. Despite initial resistance to behaviour change, the participatory approach involving monthly consultations and educational sessions facilitated the adoption of safe food-handling practices and sanitation. Market authorities assumed important leadership roles during the interventions and this helped shift attitudes towards regulation and market maintenance needs. This shift may enhance the sustainability of the interventions.

Penrith M.-L.,University of Pretoria | Vosloo W.,University of Pretoria | Vosloo W.,Australian Animal Health Laboratory | Jori F.,CIRAD - Agricultural Research for Development | And 2 more authors.
Virus Research | Year: 2013

African swine fever was reported in domestic pigs in 26 African countries during the period 2009-2011. The virus exists in an ancient sylvatic cycle between warthogs (. Phacochoerus africanus) and argasid ticks of the Ornithodoros moubata complex in many of the countries reporting outbreaks and in two further countries in the region. Eradication of the virus from the countries in eastern and southern Africa where the classic sylvatic cycle occurs is clearly not an option. However, the virus has become endemic in domestic pigs in 20 countries and the great majority of outbreaks in recent decades, even in some countries where the sylvatic cycle occurs, have been associated with movement of infected pigs and pig meat. Pig production and marketing and ASF control in Africa have been examined in order to identify risk factors for the maintenance and spread of ASF. These include large pig populations, traditional free-range husbandry systems, lack of biosecurity in semi-intensive and intensive husbandry systems, lack of organisation in both pig production and pig marketing that results in lack of incentives for investment in pig farming, and ineffective management of ASF. Most of these factors are linked to poverty, yet pigs are recognised as a livestock species that can be used to improve livelihoods and contribute significantly to food security. The changes needed and how they might be implemented in order to reduce the risk of ASF to pig producers in Africa and to the rest of the world are explored. © 2012 Elsevier B.V.

Tiller R.V.,Centers for Disease Control and Prevention | Gee J.E.,Centers for Disease Control and Prevention | Frace M.A.,Centers for Disease Control and Prevention | Taylor T.K.,Australian Animal Health Laboratory | And 3 more authors.
Applied and Environmental Microbiology | Year: 2010

We report on the characterization of a group of seven novel Brucella strains isolated in 1964 from three native rodent species in North Queensland, Australia, during a survey of wild animals. The strains were initially reported to be Brucella suis biovar 3 on the basis of microbiological test results. Our results indicated that the rodent strains had microbiological traits distinct from those of B. suis biovar 3 and all other Brucella spp. To reinvestigate these rodent strains, we sequenced the 16S rRNA, recA, and rpoB genes and nine housekeeping genes and also performed multiple-locus variable-number tandem-repeat (VNTR) analysis (MLVA). The rodent strains have a unique 16S rRNA gene sequence compared to the sequences of the classical Brucella spp. Sequence analysis of the recA, rpoB, and nine housekeeping genes reveals that the rodent strains are genetically identical to each other at these loci and divergent from any of the currently described Brucella sequence types. However, all seven of the rodent strains do exhibit distinctive allelic MLVA profiles, although none demonstrated an amplicon for VNTR 07, whereas the other Brucella spp. did. Phylogenetic analysis of the MLVA data reveals that the rodent strains form a distinct clade separate from the classical Brucella spp. Furthermore, whole-genome sequence comparison using the maximal unique exact matches index (MUMi) demonstrated a high degree of relatedness of one of the seven rodent Brucella strains (strain NF 2653) to another Australian rodent Brucella strain (strain 83-13). Our findings strongly suggest that this group of Brucella strains isolated from wild Australian rodents defines a new species in the Brucella genus. Copyright © 2010, American Society for Microbiology.

Curran J.M.,Murdoch University | Robertson I.D.,Murdoch University | Ellis T.M.,30 Leonard Street | Selleck P.W.,Australian Animal Health Laboratory
Avian Diseases | Year: 2014

Evaluation of avian influenza virus (AIV) diagnostic methods, including a nucleoprotein (NP) competitive enzyme-linked immunosorbent assay (c-ELISA), hemagglutination inhibition (HI) test, type A real-time reverse transcription polymerase chain reaction (RRT-PCR), and embryonating chicken egg (ECE) virus isolation (VI), suggested validity of these tests in wild birds comparable to that reported in poultry. This was determined by analyzing the results from experimental inoculation of three species of wild birds with a low-pathogenicity AIV and from field surveillance data. The NP c-ELISA in a high-AIV prevalence setting had 100% diagnostic sensitivity (Se; 95% confidence interval [CI]: 81.5%-100%) and 91% diagnostic specificity (Sp; 95% CI: 70.8%-98.9%) in negative controls compared with the RRT-PCR. In low-AIV prevalence flocks using a >60% inhibition positivity threshold, relative to the HI test, c-ELISA performed with 90.5% Se (95% CI: 86.2%-93.8%) and 41.2% Sp (95% CI: 38.1%-44.5%). Assessment of HI suggests a titer ≥8 is a positive test result in wild-bird sera, and using this titer had 83.3% Se (95% CI: 58.6%-96.4%) in experimentally infected birds. The RRT-PCR diagnostic performance compared with VI in cloacal swabs varied over 2-6 days postinoculation, having high Se (83.3%-100%) and Sp (94.1%-100%) with substantial agreement (kappa = 0.8). The cycle thresholds (Ct) for the RRT-PCR of Ct < 37 for positivity and Ct = 37-40 as indeterminate were found to be valid for the species included in this study. In view of the interpretative diagnostic difficulties in heterogeneous populations of wild birds, this evaluation in three species of wild birds and in surveillance data should provide greater confidence in the application of these methods routinely used in poultry. © American Association of Avian Pathologists.

Henning J.,University of Queensland | Wibawa H.,Australian Animal Health Laboratory | Morton J.,University of Queensland | Usman T.B.,Disease Investigation Center | And 2 more authors.
Emerging Infectious Diseases | Year: 2010

In Java, Indonesia, during March 2007-March 2008, 96 farms with scavenging ducks that were not vaccinated against highly pathogenic avian influenza (HPAI) were monitored bimonthly. Bird-level (prevalence among individual birds) H5 seroprevalence was 2.6% for ducks and 0.5% for chickens in contact with ducks. At least 1 seropositive bird was detected during 19.5% and 2.0% of duck- and chickenflock visits, respectively. Duck flocks were 12.4× more likely than chicken flocks to have seropositive birds. During 21.4% of farm visits, ≥1 sampled duck was H5 seropositive when all sampled in-contact chickens were seronegative. Subtype H5 virus was detected during 2.5% of duck-flock visits and 1.5% of chicken-flock visits. When deaths from HPAI infection occurred, H5 virus shedding occurred in apparently healthy birds on 68.8% of farms. Of 180 poultry deaths investigated, 43.9% were attributed to H5 virus. These longitudinal study results indicate that ducks are a source of infection for chickens and, potentially, for humans.

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