Novel estimation of African swine fever transmission parameters within smallholder villages in Lao P.D.R.

African Swine Fever (ASF) disease transmission parameters are crucial for making response and control decisions when faced with an outbreak, yet they are poorly quantified for smallholder and village contexts within Southeast Asia. Whilst disease-specific factors - such as latent and infectious periods - should remain reasonably consistent, host, environmental and management factors are likely to affect the rate of disease spread. These differences are investigated using Approximate Bayesian Computation with Sequential Monte-Carlo methods to provide disease parameter estimates in four naïve pig populations in villages of Lao People's Democratic Republic. The villages represent smallholder pig farmers of the Northern province of Oudomxay and the Southern province of Savannakhet, and the model utilised field mortality data to validate the transmission parameter estimates over the course of multiple model generations. The basic reproductive number between-pigs was estimated to range from 3.08 to 7.80, whilst the latent and infectious periods were consistent with those published in the literature for similar genotypes in the region (4.72 to 6.19 days and 2.63 to 5.50 days, respectively). These findings demonstrate that smallholder village pigs interact similarly to commercial pigs, however the spread of disease may occur slightly slower than in commercial study groups. Furthermore, the findings demonstrated that despite diversity across the study groups, the disease behaved in a consistent manner. This data can be used in disease control programs or for future modelling of ASF in smallholder contexts.

Effect of probiotics and prebiotics on the composition of the equine fecal and seminal microbiomes and sperm quality: A pilot study.

Probiotic and prebiotic effects on equine semen and gastrointestinal microbiome composition and sperm quality are unknown. This study aimed to evaluate the effects of pre-, pro- or synbiotic supplementation on fecal and semen microbiome composition and sperm quality parameters of stallions. This Latin square crossover trial involved four miniature pony stallions receiving control diet only, or addition of a pro-, pre- or synbiotic formulation. Full-length 16S rRNA gene amplicon sequencing was used to measure diversity of semen and fecal microbiomes. Total sperm count, total motility, progressive motility, DNA integrity, lipid peroxidation and mitochondrial oxidative stress, biomarkers of sperm quality, were measured after each intervention. A general linear model was employed to analyse and compare microbiome diversity measures and sperm quality data across four time points. Shannon's diversity index (alpha-diversity), and evenness of semen and gastrointestinal microbiomes were significantly different (p<0.001). A trend was observed for prebiotic effects on the diversity indices of the GI microbiome (p= 0.07). No effects of treatments were observed on either semen microbiome or sperm quality. Pre-, pro- and synbiotic supplements showed no negative effect on sperm quality parameters observed. This proof of concept provides preliminary data to inform future studies exploring the relationship between microbiomes and fertility.

The semen microbiome of miniature pony stallions.

CONTEXT: Little is known about the microbial composition of stallion semen. AIMS: To describe the microbiota detected in equine semen of healthy miniature pony stallions. METHODS: Semen specimens were collected using a Missouri artificial vagina at a single time point. PacBio (Pacific Biosciences) genomic DNA sequencing of the 16S rRNA gene was performed on these specimens, following which next-generation microbiome bioinformatics platform QIIME2 was used to process fastq files and analyse the amplicon data. The data were categorised into genus, family, class, order and phylum. KEY RESULTS: Firmicutes and Bacteroidetes phyla predominated (76%), followed by Proteobacteria (15%). Bacteroidales, Clostridiales and Cardiobacteriales predominated the microbial rank of order (86%). Class was mainly composed of Bacteroidia, Clostridia and Gammaproteobacteria (87%), while family was mainly composed of Porphyromonadaceae , Family_XI and Cardiobacteriaceae (62%). At the level of genus, 80% of the abundance was composed of seven genera, namely Porphyromonas, Suttonella, Peptoniphilus, Fastidiosipila, Ezakiella, Petrimonas and an unknown taxon. CONCLUSIONS: The findings indicate that specific microbiota may be characteristic of healthy miniature pony stallions' semen with some inter-individual variations observed. IMPLICATIONS: Larger equine studies involving fertile and infertile subjects could be informed by this study and could explore the relationship of the semen microbiome to male fertility.

Serum vitamin C status of people in New South Wales: retrospective analysis of findings at a public referral hospital.

OBJECTIVES: To examine the relationship between vitamin C status and demographic factors in New South Wales on the basis of serum vitamin C test results undertaken at the central pathology laboratory in Sydney, and to assess associations with age, gender, social disadvantage, and geographic remoteness. DESIGN, SETTING: Retrospective observational study; analysis of vitamin C test results undertaken at the Royal Prince Alfred Hospital, 1 January 2017 - 31 December 2021. MAIN OUTCOME MEASURES: Vitamin C status (normal, serum concentration ≥ 40 µmol/L; hypovitaminosis C, 12-39 µmol/L; significant deficiency, < 12 µmol/L); associations of vitamin C status with year of testing, age, gender, socio-economic status (Index of Relative Socio-Economic Advantage and Disadvantage quintile), and geographic remoteness (Australian Statistical Geography Standard); rate of hypovitaminosis C or significant deficiency test results (relative to findings of normal levels; per 100 000 estimated resident population) by Statistical Area 3. RESULTS: Of 17 507 vitamin C tests undertaken during 2017-2021, 4573 were excluded (multiple tests for individuals); of 12 934 included results, 6654 were for women (51.5%), 9402 for people living in major cities (73.5%), and 81 for people in remote or very remote areas (0.6%). In multivariable multinomial regression analyses, significant deficiency (relative to normal test results) was more likely for men than women (adjusted odds ratio [aOR], 1.39; 95% confidence interval [CI], 1.27-1.52); the likelihood of hypovitaminosis C (IRSAD quintile 1 v 5, aOR, 1.35; 95% CI, 1.19-1.53) or significant deficiency (aOR, 2.07; 95% CI, 1.79-2.40) generally increased with postcode-level socio-economic disadvantage. Several of the population areas with the highest low vitamin C rates were areas of greatest disadvantage in NSW. CONCLUSIONS: The prevalence of vitamin C deficiency among older people and people living in areas of socio-economic disadvantage indicates that population assessment of vitamin C levels would be appropriate.

Brucellosis in India: Comparing exposure amongst veterinarians, para-veterinarians and animal handlers.

The exposure to Brucella species is an occupational hazard for veterinary personnel in India. In our previous study, paraveterinarians and animal handlers were found to be at higher risk of being seropositive. In the present study, we further investigate comparative exposure risk to brucellosis amongst the veterinary professionals, identify risk factors, and evaluate the perceptions and practices towards using adequate personal protective equipment (PPE) while attending high risk veterinary interventions. A cross-sectional study was conducted amongst veterinary personnel in the Punjab state of India. Logistic and negative binomial regression models were constructed to interpret the influence of categorical and numerical variables on prevalence of brucellosis and the adequacy of PPE use, respectively. Compared to veterinarians, animal handlers were less likely to consider veterinary practice in sheep and goats (odds ratio [OR] 0.3; 95% confidence interval [CI]: 0.2-0.7) or assisting in obstetric interventions (OR 0.3, 95% CI 0.1-0.8) as potential exposures. They were less aware of the signs and symptoms of the disease in humans (OR 0.05, 95% CI 0.02-0.14) and of the availability of vaccines for cattle (OR 0.07, 95% CI 0.01-0.3) than the veterinarians, and were least likely of the three groups to recommend vaccination of cattle against brucellosis to animal owners (OR 0.1, 95% CI 0.02-0.3). Compared to veterinarians, they were also less likely to consider zoonotic risk (OR 0.4, 95% CI 0.2-0.8) or better efficiency (OR 0.1, 95% CI 0.05-0.4) as enablers of PPE use during veterinary procedures. Of the three occupational groups, animal handlers were also less likely to use adequate PPE during high-risk veterinary exposures, although they were found to have handled the highest number of cases of abortion. The average use of adequate PPE during high-risk interventions in one month preceding this study was lowest for animal handlers. Veterinary personnel with a higher rate of PPE use during high-risk veterinary interventions were likely to obtain information on brucellosis from government sources (p = 0.06) and felt that PPE use enhanced their professional efficiency (Incidence rate ratio [IRR] 3.3, 95% CI 1.5-8.1) compared to those who were less likely to use adequate PPE. We recommend concerted efforts to increase awareness amongst veterinary personnel, particularly amongst animal handlers, regarding brucellosis and the importance of biosecurity measures in veterinary practice. Designing training courses on the importance of PPE use along with formulation of biosecurity guidelines at local levels could help reduce the prevalence of the disease in veterinary personnel.

Information delivery and the veterinarian-horse owner relationship in the context of Hendra virus in Australia.

Hendra virus (HeV) is an emerging bat-borne virus endemic in Australia that can be transmitted from horses to humans and has a high fatality rate for horses and people. Controversy surrounding HeV risk mitigation measures have strained the veterinarian-horse owner relationship. This study aimed to characterise the veterinarian-horse owner relationship in general and also in the context of HeV by analysing data derived from the 'Horse Owners and Hendra Virus: A Longitudinal Study to Evaluate Risk' (HHALTER) study. Australian horse owners were recruited via emails, social media and word-of-mouth for a series of five surveys that were administered online at six-monthly intervals over a two-year period to capture baseline knowledge, attitudes and practices of horse owners regarding HeV and any changes over time. In the current study, descriptive analyses of information sources were performed to understand the use of veterinarians as a HeV information source (Surveys 1 and 5; n = 1195 and n = 617). Ordinal logistic regression analyses were conducted to determine factors associated with the frequency of horse owner contact with a veterinarian (Survey 3; n = 636). This study found a relative increase over the study period in the proportion of horse owners who had used veterinarians as HeV information source in the last 12 months (from 51.9% to 88.3%). Owning more horses, being older, having a 'duty of care' for other people working with horses and deriving the main income from horse related business were factors associated with more frequent veterinary contact. Results suggest that traditional information sources such as workshops, information packs and risk training are likely to be used by horse owners. Smart phone applications should be considered for use in the future and require further investigation for horse health communication. The findings of this study may be helpful in optimising strategies for horse health information delivery.

Investigating baseline red meat slaughter operator capacity and directions for development in Lao PDR.

A study of operator knowledge, attitudes and practices (KAP) in red meat slaughter premise operations in northern Laos was conducted and compared with international best practice, to inform future industry development. The survey interviewed 68 (of 94 possible participants) employees from all ten commercial slaughter premises in six districts in three northern Laos provinces. This was supported by observations of slaughter premises, processes and the conduct of personnel. Descriptive analysis and linear regression modelling identified significant KAP predictor factors, and a gap analysis supported or rejected inferences from the generally low KAP scores for human and animal health, animal welfare, good manufacturing practices (GMP), work conditions and economics. The median proportion of correctly/desirably answered knowledge-related questions was 35.2% (interquartile range [IQR] = 22.2-51.9%) with 27.3% (IQR = 15.9-31.8%) for the attitude-related questions and 21.4% (IQR = 14.3-35.7%) for the practice-related questions. Two districts had significantly lower KAP scores than other districts, and staff had the lowest and meat inspectors had the highest scores. This study indicates that the current KAP for red meat processing falls short of international standards and that training programmes on disease risks and prevention are important in facilitating red meat industry development.

Triggers for Preeclampsia Onset: a Case-Crossover Study.

BACKGROUND: Risk factors for preeclampsia are well established, whereas, the triggers associated with timing of preeclampsia onset are not. The aim of this study was to establish whether recent infection or other triggers were associated with timing of preeclampsia onset. METHODS: We used a case-crossover design with preeclampsia cases serving as their own controls. Women with singleton pregnancies of ≥20 weeks gestation presenting at three hospitals were eligible for inclusion. Exposures to potential triggers were identified via guided questionnaire. Infective episodes included symptoms lasting >24 h. Preeclampsia was defined as hypertension (BP ≥140 mmHg and/or ≥90 mmHg) and proteinuria (protein/creatinine ratio ≥30 mg/mmol). Conditional logistic regression was used to compare the odds of exposure to potential triggers in the case windows (1-7 days preceding diagnosis of preeclampsia) and control windows (8-14 days prior to diagnosis); unadjusted odds ratios (ORs) are reported. RESULTS: Among 286 recruited women, 25 (8.7%) reported a new infection in the 7 days prior to preeclampsia onset and 21 (7.3%) in the 8-14 days prior. There was no significant association between onset of infection in the 7 days prior and preeclampsia diagnosis (OR 1.24, 95% CI 0.65, 2.34). Consumption of caffeine (OR 0.51, 95% CI 0.33, 0.77), spicy food (OR 0.49, 95% CI 0.30, 0.81), and alcohol (OR 0.26, 95% CI 0.10, 0.71) were strongly inversely associated with preeclampsia onset. CONCLUSION: Recent infection does not appear to trigger preeclampsia. Decreased consumption of caffeine, spicy food, and alcohol may be prodromal markers. Such behaviours may be early markers of imminent preeclampsia.

Variation in and factors associated with timing of low risk, pre-labour repeat caesarean sections in NSW, 2008-2011.

OBJECTIVE: To explore variation in public hospital rates of early (37-38 weeks gestation) prelabour repeat caesarean section among low-risk women at and beyond term in New South Wales (NSW) between 2008 and 2011. IMPORTANCE OF THE STUDY: A NSW Ministry of Health policy directive for public hospitals (PD2007_024), 'Maternity - timing of elective or pre-labour caesarean section', requires that low-risk elective or prelabour caesarean section does not occur before 39 completed weeks gestation. However, compliance with this policy has not been evaluated. STUDY TYPE: Population-based record linkage study Methods: Linked birth and hospital data for low-risk, prelabour repeat caesarean sections in NSW in 2008-2011 were analysed using multilevel regression modelling. Rates were adjusted for casemix and hospital factors. Low-risk pregnancies were defined as singleton live births at 37-42 weeks gestation among women without medical or obstetric complications and where the indication for caesarean section was 'elective repeat caesarean section'. RESULTS: In 2008-2011, there were 15 163 prelabour repeat caesarean sections among low-risk women in NSW. Overall, 34.7% of low-risk prelabour repeat caesarean sections occurred before 39 weeks gestation. Adjusted NSW public hospital rates of early (37-38 weeks gestation) low-risk prelabour repeat caesarean section varied widely (16.3-67.5%). Adjusting for casemix factors actually increased the between-hospital variation by 4.3%; adjusting for hospital factors reduced variation by 20.0%. Smoking, private healthcare, assisted reproductive technology use, higher parity, a noncaesarean uterine scar and delivering in a hospital with CPAP (continuous positive airway pressure) facilities were associated with higher odds of early delivery, although infants that were small for gestational age were associated with lower odds. Hospitals with higher rates of low-risk deliveries and higher propensity for vaginal birth after caesarean section had lower odds of early delivery. CONCLUSIONS: The findings suggest generally poor compliance with the policy directive that prelabour caesarean does not occur before 39 weeks gestation, with adjusted compliance rates ranging from 32.5% to 83.7%. Large between-hospital variation after adjustment suggests that nonmedical factors are related to timing of low-risk prelabour repeat caesarean sections. Further strategies are needed to improve adherence to this evidence based policy.

Prevalence of noncaesarean uterine surgical scars in a maternity population.

The prevalence of noncaesarean section uterine surgical scars in a general obstetric population was 3.0 of 1000 deliveries and among nulliparae 3.4 of 1000 deliveries, calculated from population data of all delivery records in New South Wales from 2005 to 2011. As the population prevalence is low, women with a noncaesarean section uterine surgical scar are unlikely to impact the analyses of factors associated with caesarean section.

Variation in hospital caesarean section rates for women with at least one previous caesarean section: a population based cohort study.

BACKGROUND: Internationally, repeat caesarean sections make the largest contribution to overall caesarean section rates and inter-hospital variation has been reported. The aim of this study was to determine if casemix and hospital factors explain variation in hospital rates of repeat caesarean sections and whether these rates are associated with maternal and neonatal morbidity. METHODS: This population-based record linkage study utilised data from New South Wales, Australia between 2007 and 2011. The study population included maternities with any previous caesarean section(s) and were singleton, cephalic and ≥ 37 weeks' gestation (Robson Group 5). Multilevel regression models were used to examine variation in hospital rates of 'planned repeat caesarean section' and, among women who planned a vaginal birth, 'intrapartum caesarean section'. We assessed associations between risk-adjusted hospital rates of planned and intrapartum caesarean sections and rates of casemix adjusted maternal and neonatal morbidity, postpartum haemorrhage and Apgar score <7 at five minutes. RESULTS: Of 61894 maternities with a previous caesarean section in 81 hospitals, 82.1% resulted in a caesarean section (72.7% planned and 9.4% unplanned intrapartum caesareans) and 17.9% in vaginal birth. Observed hospital rates of planned caesarean sections ranged from 50.7% to 98.4%. Overall 49.0% of between-hospital variation in planned repeat caesarean section rates was explained by patient (17.3%) and hospital factors (31.7%). Increased odds of planned caesarean section were associated with private hospital status and lower hospital propensity for vaginal birth after caesarean. There were no associations between hospital rates of planned repeat caesarean section and adjusted morbidity rates. Among women who intended a vaginal birth, the observed rates of intrapartum caesarean section ranged from 12.9% to 71.9%. In total, 27.5% of between-hospital variation in rates of intrapartum caesarean section was explained by patient (19.5%) and hospital factors (8.0%). The adjusted morbidity rates differed among hospital intrapartum caesarean section rates, but were influenced by a few hospitals with outlying morbidity rates. CONCLUSIONS: Among women with at least one previous caesarean section, less than half of the variation in hospital caesarean section rates was explained by differences in hospital's patient characteristics and practices. Strategies aimed at modifying caesarean section rates for these women should not affect morbidity rates.

Applying Bayesian network modelling to understand the links between on-farm biosecurity practice during the 2007 equine influenza outbreak and horse managers' perceptions of a subsequent outbreak.

Australia experienced its first ever outbreak of equine influenza in August 2007. Horses on 9359 premises were infected over a period of 5 months before the disease was successfully eradicated through the combination of horse movement controls, on-farm biosecurity and vaccination. In a previous premises-level case-control study of the 2007 equine influenza outbreak in Australia, the protective effect of several variables representing on-farm biosecurity practices were identified. Separately, factors associated with horse managers' perceptions of the effectiveness of biosecurity measures have been identified. In this analysis we applied additive Bayesian network modelling to describe the complex web of associations linking variables representing on-farm human behaviours during the 2007 equine influenza outbreak (compliance or lack thereof with advised personal biosecurity measures) and horse managers' perceptions of the effectiveness of such measures in the event of a subsequent outbreak. Heuristic structure discovery enabled identification of a robust statistical model for 31 variables representing biosecurity practices and perceptions of the owners and managers of 148 premises. The Bayesian graphical network model we present statistically describes the associations linking horse managers' on-farm biosecurity practices during an at-risk period in the 2007 outbreak and their perceptions of whether such measures will be effective in a future outbreak. Practice of barrier infection control measures were associated with a heightened perception of preparedness, whereas horse managers that considered their on-farm biosecurity to be more stringent during the outbreak period than normal practices had a heightened perception of the effectiveness of other measures such as controlling access to the premises. Past performance in an outbreak setting may indeed be a reliable predictor of future perceptions, and should be considered when targeting infection control guidance to horse owners and managers.

Perceptions of vulnerability to a future outbreak: a study of horse managers affected by the first Australian equine influenza outbreak.

BACKGROUND: A growing body of work shows the benefits of applying social cognitive behavioural theory to investigate infection control and biosecurity practices. Protection motivation theory has been used to predict protective health behaviours. The theory outlines that a perception of a lack of vulnerability to a disease contributes to a reduced threat appraisal, which results in poorer motivation, and is linked to poorer compliance with advised health protective behaviours. This study, conducted following the first-ever outbreak of equine influenza in Australia in 2007, identified factors associated with horse managers' perceived vulnerability to a future equine influenza outbreak. RESULTS: Of the 200 respondents, 31.9% perceived themselves to be very vulnerable, 36.6% vulnerable and 31.4% not vulnerable to a future outbreak of equine influenza. Multivariable logistic regression modelling revealed that managers involved in horse racing and those on rural horse premises perceived themselves to have low levels of vulnerability. Managers of horse premises that experienced infection in their horses in 2007 and those seeking infection control information from specific sources reported increased levels of perceived vulnerability to a future outbreak. CONCLUSION: Different groups across the horse industry perceived differing levels of vulnerability to a future outbreak. Increased vulnerability contributes to favourable infection control behaviour and hence these findings are important for understanding uptake of recommended infection control measures. Future biosecurity communication strategies should be delivered through information sources suitable for the horse racing and rural sectors.

Untangling the complex inter-relationships between horse managers' perceptions of effectiveness of biosecurity practices using Bayesian graphical modelling.

On-farm biosecurity practices have been promoted in many animal industries to protect animal populations from infections. Current approaches based on regression modelling techniques for assessing biosecurity perceptions and practices are limited for analysis of the interrelationships between multivariate data. A suitable approach, which does not require background knowledge of relationships, is provided by Bayesian network modelling. Here we apply such an approach to explore the complex interrelationships between the variables representing horse managers' perceptions of effectiveness of on-farm biosecurity practices. The dataset was derived from interviews conducted with 200 horse managers in Australia after the 2007 equine influenza outbreak. Using established computationally intensive techniques, an optimal graphical statistical model was identified whose structure was objectively determined, directly from the observed data. This methodology is directly analogous to multivariate regression (i.e. multiple response variables). First, an optimal model structure was identified using an exact (exhaustive) search algorithm, followed by pruning the selected model for over-fitting by the parametric bootstrapping approach. Perceptions about effectiveness of movement restrictions and access control were linked but were generally segregated from the perceptions about effectiveness of personal and equipment hygiene. Horse managers believing in the effectiveness of complying with movement restrictions in stopping equine influenza spread onto their premises were also more likely to believe in the effectiveness of reducing their own contact with other horses and curtailing professional visits. Similarly, the variables representing the effectiveness of disinfecting vehicles, using a disinfectant footbath, changing into clean clothes on arrival at the premises and washing hands before contact with managed horses were clustered together. In contrast, horse managers believing in the effectiveness of disinfecting vehicles (hygiene measure) were less likely to believe in the effectiveness of controlling who has access to managed horses (access control). The findings of this analysis provide new insights into the relationships between perceptions of effectiveness of different biosecurity measures. Different extension education strategies might be required for horse managers believing more strongly in the effectiveness of access control or hygiene measures.

Understanding the associations between on-farm biosecurity practice and equine influenza infection during the 2007 outbreak in Australia.

In a previous premises-level case-control study of the 2007 equine influenza outbreak in Australia, the protective effect of several variables representing on-farm biosecurity practices was identified. However, using logistic regression it was not possible to definitively identify individual effects and associations between each of the personal biosecurity measures implemented by horse premises owners and managers in the face of the outbreak. In this study we apply Bayesian network modelling to identify the complex web of associations between these variables, horse premises infection status and other premises-level covariates. We focussed this analysis primarily on the inter-relationship between the nine variables representing on-farm personal biosecurity measures (of people residing on the premises and those visiting), and all other variables from the final logistic regression model of our previous analysis. Exact structure discovery was used to identify the globally optimal model from across the landscape of all directed acyclic graphs possible for our dataset. Bootstrapping was used to adjust the model for over-fitting. Our final Bayesian graphic network model included 18 variables linked by 23 arcs, each arc analogous to a single multivariable generalised linear model, combined in a probabilistically coherent way. Amongst the personal biosecurity measures, having a footbath in place, certain practices of visitors (hand-washing, changing clothes and shoes) in contact with the horses, and the regularity of horse handling were statistically associated with premises infection status. The results of this in-depth analysis provide new insight into the complex web of direct and indirect associations between risk factors and horse premises infection status during the first 7 weeks of the 2007 equine influenza outbreak in Australia. In future outbreaks, unnecessary contact and handling of horses should be avoided, especially by those coming from off the premises. Prior to any such contact, persons handling horses should use a footbath (if present), change their clothes and shoes, and wash their hands.

A cross-sectional study on biosecurity practices and communication networks of poultry exhibition in Australia.

Poultry exhibitors are perceived to pose a biosecurity risk due to the high frequency of movements of birds and the close contact between birds at poultry shows. This cross-sectional study assessed the risks posed by poultry exhibitors in Australia using face-to-face interviews (n=46) at eight poultry shows and a postal survey. Univariable and multivariable logistic regression analyses were used to investigate associations between age, sex, location, number of birds, number of shows attended per year and distance travelled to a show, with biosecurity and communication practices. A total of 357 (29.1%) exhibitors responded to the postal survey. Among all participants (n=403), most had owned poultry for more than 15 years (71.9%), kept less than 200 birds (83.4%), mainly chicken (96.7%) and waterfowl (17.8%), and reported not having any commercial poultry operation within 5 km of their property (85.4%). Despite most exhibitors (90.8%) having at least some knowledge of biosecurity principles; some of their practices could pose a risk for disease introduction and spread. Most exhibitors kept their birds with outdoor access (87.0%) and 67.0% of exhibitors reported contact of wild birds with domestic birds being possible. Only 60% and 40.6% of exhibitors cleaned transport cages after each use and isolated birds for over two weeks, respectively, with men and exhibitors keeping more birds less likely (P=0.003) to conduct this practice. Most exhibitors (75.0%) attended more than 5 shows per year, travelling long distances (up to 1000 km) to attend a show. Although most exhibitors would source and sell their birds from and to other exhibitors and at poultry shows, some reported sourcing (15.2%) and selling (25.3%) their birds at live bird markets. In addition, contact with veterinarians was low (23.1%), with younger exhibitors and women more likely to contact a veterinarian than older exhibitors (P=0.006) and men (P=0.017). Other poultry exhibitors were reported as the most useful source of information, followed by the poultry club, the veterinarian and Internet. Less than a quarter of exhibitors perceived the government agencies as a useful source of information. Newspapers, newsletters, emails and websites were the preferred methods of information delivery. However, information seeking behaviour was found to differ significantly (P<0.05) among gender and different age groups. Differing biosecurity, health and communication practices among poultry exhibitors found in this study need to be considered for the development of successful biosecurity extension and communication programmes.

A case-control study of risk factors for equine influenza spread onto horse premises during the 2007 epidemic in Australia.

The 2007 epidemic of equine influenza in Australia provided an opportunity to investigate the effectiveness of on-farm biosecurity measures in preventing the spread of a novel pathogen in a largely naive population. We conducted a case-control study of 200 horse premises from highly affected regions of the state of New South Wales (NSW), to investigate risk factors for the spread of equine influenza onto horse premises, specifically, non-compliance with biosecurity measures recommended to horse owners by the relevant animal health authority, the NSW Department of Primary Industries. The study was restricted to cases occurring during the first seven weeks of the epidemic, a period prior to vaccination and the relaxation of some movement restrictions. Case and control premises were selected from a laboratory testing dataset and interviews were conducted with horse owners and managers on premises between July and November 2009. The proximity of premises to the nearest infected premises was the factor most strongly associated with case status. Case premises were more likely than control premises to be within 5 km and beyond 10 km of an infected premises. Having a footbath in place on the premises before any horses were infected was associated with a nearly four-fold reduction in odds of infection (odds ratio=0.27; 95% confidence interval: 0.09, 0.83). This protective association may have reflected overall premises biosecurity standards related to the fomite transmission of equine influenza. Compliance with certain on-farm biosecurity practices seemingly prevented horses on premises in high risk areas being infected with equine influenza during the 2007 outbreak in Australia. In future outbreaks, in addition to broader disease control measures, on-farm biosecurity practices should be adopted by horse owners and managers to prevent equine influenza spread.