Fine-temporal forecasting of outbreak probability and severity: Ross River virus in Western Australia.

Health warnings of mosquito-borne disease risk require forecasts that are accurate at fine-temporal resolutions (weekly scales); however, most forecasting is coarse (monthly). We use environmental and Ross River virus (RRV) surveillance to predict weekly outbreak probabilities and incidence spanning tropical, semi-arid, and Mediterranean regions of Western Australia (1991-2014). Hurdle and linear models were used to predict outbreak probabilities and incidence respectively, using time-lagged environmental variables. Forecast accuracy was assessed by model fit and cross-validation. Residual RRV notification data were also examined against mitigation expenditure for one site, Mandurah 2007-2014. Models were predictive of RRV activity, except at one site (Capel). Minimum temperature was an important predictor of RRV outbreaks and incidence at all predicted sites. Precipitation was more likely to cause outbreaks and greater incidence among tropical and semi-arid sites. While variable, mitigation expenditure coincided positively with increased RRV incidence (r 2 = 0·21). Our research demonstrates capacity to accurately predict mosquito-borne disease outbreaks and incidence at fine-temporal resolutions. We apply our findings, developing a user-friendly tool enabling managers to easily adopt this research to forecast region-specific RRV outbreaks and incidence. Approaches here may be of value to fine-scale forecasting of RRV in other areas of Australia, and other mosquito-borne diseases.

Bridging the evidence-to-practice gap: exploring dental professionals' perspectives on managing oral health during pregnancy in Tasmania, Australia.

BACKGROUND: Poor oral health is associated with adverse health, social and economic consequences for pregnant women. While dental professionals promote good oral health within the dental practice context, more broadly, women in the antenatal period face poor oral health outcomes. Therefore, this study explored dental professionals' perceptions of their role in managing the oral health of pregnant women and identified the barriers and facilitators to improving maternal oral health. METHODS: This study employed a descriptive qualitative method utilizing semi-structured interviews. Convenience and snowball sampling were used to recruit 13 dental professionals from Tasmania, Australia, comprising dentists (n = 10), oral health therapists (n = 2) and dental therapist (n = 1). Interviews were audio-recorded, transcribed verbatim and analysed using inductive thematic analysis. RESULTS: Three major themes were constructed from the interviews: (1) dental professionals' oral health care of women during pregnancy; (2) perceived challenges to maternal oral health; and (3) proposed strategies to improve maternal oral health. CONCLUSIONS: Findings suggest dental professionals' competence in maternal oral health, but that several barriers, such as dental care access and maternal factors, hinder oral health outcomes. To address these barriers, oral health policies that support interprofessional collaboration, professional training and evaluation of existing community oral health programmes are needed. © 2024 Australian Dental Association.

A systematic review assessing the effectiveness of interventions to improve persistence with anti-resorptive therapy in women at high risk of clinical fracture.

BACKGROUND: despite availability of effective treatments for osteoporosis, impact on fracture rates may be suboptimal because of failure to adhere to recommended anti-resorptive therapy. OBJECTIVE: to identify randomized controlled trials (RCTs) evaluating interventions intended to improve persistence with anti-resorptive therapy for treating women with osteoporosis or osteopenia. The design of the study is a systematic review and meta-analysis of RCTs. METHODS: included trials were those reporting interventions to improve persistence with or adherence to anti-resorptive treatment compared to a control medication or usual care. A search of MEDLINE, EMBASE, CINAHL and the Cochrane Library was supplemented by review of cited literature. Reports were reviewed and data pooled where appropriate. The primary outcome was duration of persistence with medication. RESULTS: six trials met inclusion criteria, including four reporting persistence as an outcome measure indicating a relative reduction in non-persistence of 22% (pooled relative risk: 0.78, 95% confidence interval 0.65-0.95) for active compared to control interventions. Heterogeneity between the trial effects was present but not significant (I(2) = 47%, P = 0.11). Interventions were varied in design, and some measurements of adherence were subject to self-report bias. Two trials included the majority of participants (3386/3497), accounting for >90% of the weight in the pooled estimate. CONCLUSIONS: trials to date suggest potential for improving persistence with medication taking thus improving treatment outcomes and reducing fracture risk. More precise measurement of medication taking and promoting fidelity to a precisely defined intervention protocol may lead to better assessment of impact on clinically important outcomes.

Mitogen-induced responses in lymphocytes from platypus, the Tasmanian devil and the eastern barred bandicoot.

OBJECTIVE: As the platypus (Ornithorhynchus anatinus), the Tasmanian devil (Sarcophilus harrisi) and the eastern barred bandicoot (Perameles gunni) are currently at risk of serious population decline or extinction from fatal diseases in Tasmania, the goal of the present study was to describe the normal immune response of these species to challenge using the lymphocyte proliferation assay, to give a solid basis for further studies. METHODS: For this preliminary study, we performed lymphocyte proliferation assays on peripheral blood mononuclear cells (PBMC) from the three species. We used the common mitogens phytohaemagglutinin (PHA), concanavalin A (ConA), lipopolysaccharide (LPS) and pokeweed mitogen (PWM). RESULTS: All three species recorded the highest stimulation index (SI) with the T-cell mitogens PHA and ConA. Tasmanian devils and bandicoots had greater responses than platypuses, although variability between individual animals was high. CONCLUSION: For the first time, we report the normal cellular response of the platypus, the Tasmanian devil and the eastern barred bandicoot to a range of commonly used mitogens.

Is overweight/obesity a risk factor for periodontitis in young adults and adolescents?: a systematic review.

BACKGROUND: Obesity in young adults and adolescents is associated with chronic co-morbidities. This project investigated whether being overweight or obese is a risk factor for periodontitis in adolescents (13-17 years) and young adults (18-34 years). METHODS: A search of 12 databases was conducted using Medical Subject Headings/Index and Emtree terms. Based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, articles published between 2003 and 2016 were screened that reported periodontal and anthropometric measures. The Newcastle-Ottawa Scale was used to appraise the quality of studies. RESULTS: Of 25 eligible studies from 12 countries, 17 showed an association between obesity and periodontitis (odds ratios ranged from 1.1 to 4.5). The obesity indicators of body mass index, waist circumference, waist-hip ratio and body fat percentage were significantly associated with measures of periodontitis of bleeding on probing, plaque index, probing depths, clinical attachment loss, calculus, oral hygiene index and community periodontal index. Two prospective cohort studies in the review showed no significant association between obesity and periodontitis, but these studies had limitations of study design and used inappropriate epidemiological diagnostic measures of periodontitis. CONCLUSION: There was evidence to suggest that obesity is associated with periodontitis in adolescents and young adults. Systematic Review Registration: PROSPERO Registration Number: CRD42016046507.

Isolation of verotoxigenic Escherichia coli from the Tasmanian environment.

Growing concerns on the emergence of verotoxin producing Escherichia coli (VTEC) in Australia have focused our attention on the possible sources of VTEC within the island state of Tasmania. An analysis of 156 food samples and 194 water samples obtained from various areas revealed evidence of eight possible sources. Six strains, with serotypes Ont:Hnt, O86:H-, O88:H-, O126:H21 and O134:H-, were isolated from water samples. Two VTEC of serotypes Ont:H8, 081:H- were isolated from raw meat samples. The waterborne isolates produced verocytotoxin. VT1, while both foodborne isolates were strong producers of VT2. Three VTEC isolates produced haemolysins, only one produced enterohaemolysin (EntHly) and the remaining were reported with alpha-haemolysin (alpha-Hly) activity. An important feature in the majority of isolates from water was their lack of ability to ferment lactose these isolates are routinely overlooked in public health laboratories.

Epidemiology of giardiasis in Tasmania: a potential risk to residents and visitors.

BACKGROUND: Giardia infection is an ongoing problem in Tasmania and occurs throughout the state. It has been postulated that part of the problem is the reservoir of infection in native animals which is suggested to contribute to infections in humans. To date, however, no detailed study on the epidemiology of giardiasis in Tasmania has been carried out. METHODS: Information regarding the prevalence of Giardia infection in humans and the risk of intrafamilial transmission was obtained from the Department of Community and Health Services and from the direct examination of human or animal fecal samples. RESULTS: Giardia has been found to be present in a wide range of native and domestic animals and in humans of all ages from all over the state. CONCLUSIONS: Giardiasis is endemic in Tasmania and poses a risk to locals as well as to visitors to the state, especially those who participate in wilderness activities such as bushwalking. These people must be aware of the possible risk of Giardia infection and should take precautionary measures to avoid infection.

The first record of a member of the genus Hepatozoon in the eastern barred bandicoot (Perameles gunnii) in Tasmania.

Of 220 wild Eastern Barred Bandicoots (Perameles gunnii) captured in two locations in Tasmania, Australia, 55 (25%) had a detectable parasitaemia with gametocytes of the protozoan genus Hepatozoon in blood films. Blood films were stained with Leishman stain and acridine orange O. Gamonts were commonly found as intracellular forms and occasionally observed as extracellular forms in peripheral erythrocytes. This is the first record of a member of the genus Hepatozoon in any temperate bandicoot and additionally appears to be the first record of this protozoan genus in any native marsupial species of Tasmania.

First record of trypanosomes in Tasmanian bandicoots.

Trypanosomes were observed in 38% of blood smears from southern brown bandicoots (Isoodon obesulus) and in 10% of blood smears from eastern barred bandicoots (Perameles gunnii). This is the first record of such hemoparasites in Tasmanian marsupials. There appeared to be a statistically significant size difference between trypanosomes found in the 2 bandicoot species, suggesting the possibility of 2 distinct species of parasite. There appears to be a distinction between the trypanosomes found in our temperate Isoodon species and the tropical bandicoot. Isoodon macrurus. The use of the microhematocrit method provided an effective means for concentrating trypanosomes, whereas image analysis was a more effective method than the ocular micrometer for obtaining accurate measurements.

Pathology of experimental toxoplasmosis in eastern barred bandicoots in Tasmania.

Wild-caught eastern barred bandicoots (Perameles gunnii) initially seronegative to Toxoplasma gondii, were inoculated orally with approximately 100 T. gondii oocysts. The bandicoots were maintained in indoor pens under laboratory conditions and observed daily. Serial blood samples were tested for agglutinating antibodies to T. gondii. Inoculated bandicoots died 15 and 17 days post infection. A rise in Direct Agglutination Test (DAT) titres was detected at the time of death (1:256, 1:64 respectively). Clinical observations, serological changes, gross findings at necropsy, and histopathological changes were consistent with acute toxoplasmosis. The findings indicate that eastern barred bandicoots are likely to die from primary T. gondii infection, often even before detectable antibodies are produced, reinforcing the significance of toxoplasmosis as a potential contributor to the reduction in numbers of wild populations of eastern barred bandicoots.

Earthworms as paratenic hosts of toxoplasmosis in eastern barred bandicoots in Tasmania.

An experimental feeding study was designed to assess the role of earthworms in the transmission of Toxoplasma gondii infection to eastern barred bandicoots (Perameles gunnii). Six animals with no agglutinating antibodies to T. gondii were fed artificially cultured earthworms that had been maintained in autoclaved nutrient-enriched soil. Two animals were given earthworms that had been maintained in soil contaminated with T. gondii oocysts (P89/VEG strain); two animals were fed on earthworms, which initially had been exposed to soil containing T. gondii oocysts then transferred through three changes of sterile soil; two control bandicoots were fed earthworms maintained in sterile soil. Both bandicoots fed earthworms maintained in T. gondii contaminated soil died 11 and 14 days after feeding. The necropsy findings were consistent with acute toxoplasmosis. Bandicoots fed earthworms exposed to oocysts but then transferred through changes of sterilized soil remained healthy as did control animals. All surviving animals remained seronegative over the 6 wk observation period after feeding. These findings confirm that earthworms, a major component of the natural diet of P. gunnii, can transmit T. gondii infection. It appears that oocysts present in the alimentary tracts of the worms, rather than infective stages of T. gondii in worm somatic tissues, are responsible for these infections.

Giardiasis in native marsupials of Tasmania.

Tasmanian native marsupials were screened for the presence of Giardia spp. over a 3 yr period, revealing a 21% prevalence in the 295 animals tested. A pilot study of experimentally infected eastern barred bandicoots (Perameles gunnii) indicated susceptibility to infection with Giardia duodenalis from a human source.

Biosignificance of bacterial cyanogenesis in the CF lung.

Two recent studies have demonstrated the presence of biologically significant amounts of cyanide within the airways of cystic fibrosis (CF) patients infected with Pseudomonas aeruginosa. Whilst environmental strains of P. aeruginosa are known to synthesise cyanide, there has been a relative lack of investigation into bacterial cyanogenesis from a medical viewpoint, despite the role P. aeruginosa plays in many serious infection settings and especially in CF lung disease. This review discusses the implications of cyanogenesis in the CF airway in terms of bacterial ecology, host immune response, progression of lung disease and potential treatment options.

The clinical significance of Escherichia coli Alkalescens-Dispar in Tasmania.

An investigation in 1989 of human fecal specimens revealed that of 111 diarrheal samples examined Escherichia coli Alkalescens-Dispar (A-D) were found in 9 (8.1%), but none were isolated from normal stool samples. Further studies have shown that although these isolates may be potential pathogens, they seem to remain unrecognized by routine laboratories due to their biochemical similarity to shigellae, a problem further exacerbated by their extensive sharing of O antigens. All the isolates were screened with an invasive DNA probe and all but three isolates were found to have a common plasmid. They were also confirmed to be invasive in HEp-2 monolayers. No isolates were shown to produce heat-labile or heat-stable toxin but electronmicroscopy revealed the presence of pili. The A-D isolates were biotyped using the two-tier schema of Crichton and Old and were categorized into biotypes 11, 12 and 16. These data confirm the importance of introducing an awareness of this intermediate strain into routine laboratories.

Bacterial flora of Tasmanian SIDS infants with special reference to pathogenic strains of Escherichia coli.

The general bacterial flora of 38 Tasmanian SIDS infants was examined together with faecal flora of 134 comparison infants ranging in age from birth to 6 months. The microflora of all specimens received was investigated with special emphasis on the toxigenic Escherichia coli (TEC). Samples were examined for verocytotoxigenic E. coli, free faecal verocytotoxin (FVT), heat labile toxin (LT) and heat stable toxin (ST) producers with the use of a Vero cell assay and commercial kits. The findings of this study revealed a high isolation rate (39%) of TEC from SIDS infants as compared to 1.5% from the healthy comparison infants. Atypical E. coli strains were also identified during the study, including E. coli A-D. An analysis of the same specimens for rotaviral and adenoviral antigens indicated that 30% of the SIDS cases were positive as compared to 20% in the comparison group.