Outbreaks, occurrence, and control of norovirus and hepatitis a virus contamination in berries: A review.

Foodborne enteric viruses, in particular HuNoV and HAV, are the most common cause of the berry-linked viral diseases, and outbreaks around the world, and have become an important concern for health authorities. Despite the increased importance of berry fruits as a vehicle for foodborne viruses, there is limited information concerning the fate of foodborne viruses in the berry supply chain from farm to consumer. A comprehensive understanding of berry-associated viral outbreaks - with a focus on contamination sources, persistence, survival, and the effects of current postharvest and processing interventions and practices - is essential for the development of effective preventative strategies to reduce risk of illness. The purpose of this paper is twofold; (i) to critically review the published literature on the current state of knowledge regarding berry-associated foodborne viral outbreaks and the efficiency of berry processing practices and (ii) to identify and prioritize research gaps regarding practical and effective mechanism to reduce viral contamination of berries. The review found that fecally infected food handlers were the predominant source of preharvest and postharvest pathogenic viral contamination. Current industrial practices applied to fresh and frozen berries demonstrated limited efficacy for reducing the viral load. While maintaining best practice personal and environmental hygiene is a key intervention, the optimization of processing parameters (i.e., freezing, frozen storage, and washing) and/or development of alternative processing technologies to induce sufficient viral inactivation in berries along with retaining sensory and nutritional quality, is also an important direction for further research.

Assessment of microbial risk during Australian industrial practices for Escherichia coli O157:H7 in fresh cut-cos lettuce: A stochastic quantitative approach.

Escherichia coli O157:H7 risk associated with the consumption of fresh cut-cos lettuce during Australian industrial practices was assessed. A probabilistic risk assessment model was developed and implemented in the @Risk software by using the Monte Carlo simulation technique with 1,000,000 iterations. Australian preharvest practices yielded predicted annual mean E. coli O157:H7 levels from 0.2 to -3.4 log CFU/g and prevalence values ranged from 2 to 6.4%. While exclusion of solar radiation from the baseline model yielded a significant increase in concentration of E. coli O157:H7 (-5.2 -log fold), drip irrigation usage, exclusion of manure amended soil and rainfall reduced E. coli O157:H7 levels by 7.4, 6.5, and 4.3-log fold, respectively. The microbial quality of irrigation water and irrigation type both had a significant effect on E. coli O157:H7 concentrations at harvest (p < 0.05). The probability of illness due to consumption of E. coli O157:H7 contaminated fresh cut-cos lettuce when water washing interventions were introduced into the processing module, was reduced by 1.4-2.7-log fold (p < 0.05). This study provides a robust basis for assessment of risk associated with E. coli O157:H7 contamination on fresh cut-cos lettuce for industrial practices and will assist the leafy green industry and food safety authorities in Australia to identify potential risk management strategies.

Sediment re-suspension as a potential mechanism for viral and bacterial contaminants.

Pathogenic enteric viruses and bacteria tend to occur in higher concentrations and survive longer in aquatic sediments than suspended in the water column. Re-suspension of these organisms can result in a significant degradation of overlying water quality. Additionally, the re-suspension of microbial pathogens in artificial irrigation canals could endanger the consumption of fresh and ready-to-eat produce. Irrigation water has been implicated in numerous fresh produce outbreaks over the last 30 years. This study aimed to quantify the proportions of bacterial and viral re-suspension from sediment in a recirculating flume with varying velocities. MS2 coliphage and Escherichia coli were found to re-suspend at rates that were not significantly different, despite organism size differences. However, E. coli re-suspension rates from sand and clay were significantly different. This suggests that likely sediment-associated particles were recovered with the organisms attached. Similar re-suspension rates are hypothesized to be due to the dynamics of sediment transport, rather than that of the organisms themselves. This study also indicated that the re-suspension of sediment at very low velocities (e.g., less than 10 cm/s), could impact the microbiological quality of the overlaying water. Results from this study conclude that sediment could be a viable mechanism for irrigation water contamination.

Consumer evaluation of 'Veggycation®', a website promoting the health benefits of vegetables.

Issue addressed Whether the website Veggycation® appeals to particular groups of consumers significantly more than other groups. Methods Australian adults aged ≥18 years (n = 1000) completed an online survey. The website evaluation instrument used was tested for validity and reliability. Associations between demographic variables and website evaluation dimensions of attractiveness, content, user-friendliness and loyalty intentions were examined using a general linear model (GLM). The appraisal of the website was further investigated based on the respondents' daily consumption level of vegetables and the importance they attach to vegetable consumption in their diet, using GLM and a Tukey's all-pair comparison. Results Veggycation® has a high level of acceptance among the Australian community with certain groups evaluating the website more favourably. These include women, people aged≤29 years, higher income respondents, non-metro respondents and those who viewed vegetables as extremely important in their daily diet. Conclusions Customisation of the website for consumer groups with low vegetable consumption is recommended. Designing tailored communication tools will assist in enhancing the knowledge base of vegetable-related health benefits and may promote vegetable consumption among the Australian population. So what? The promotion of higher vegetable consumption is aided by tailored, well-designed web communication. This study adds to the existing body of knowledge for the education of organisations developing e-tools for promoting health education and literacy.

Microbial players involved in the decline of filamentous and colonial cyanobacterial blooms with a focus on fungal parasitism.

In the forthcoming decades, it is widely believed that the dominance of colonial and filamentous bloom-forming cyanobacteria (e.g. Microcystis, Planktothrix, Anabaena and Cylindrospermopsis) will increase in freshwater systems as a combined result of anthropogenic nutrient input into freshwater bodies and climate change. While the physicochemical parameters controlling bloom dynamics are well known, the role of biotic factors remains comparatively poorly studied. Morphology and toxicity often - but not always - limit the availability of cyanobacteria to filter feeding zooplankton (e.g. cladocerans). Filamentous and colonial cyanobacteria are widely regarded as trophic dead-ends mostly inedible for zooplankton, but substantial evidence shows that some grazers (e.g. copepods) can bypass this size constraint by breaking down filaments, making the bloom biomass available to other zooplankton species. A wide range of algicidal bacteria (mostly from the Alcaligenes, Flavobacterium/Cytophaga group and Pseudomonas) and viruses (Podoviridae, Siphoviridae and Myoviridae) may also contribute to bloom control, via their lytic activity underpinned by a diverse array of mechanisms. Fungal parasitism by the Chytridiomycota remains the least studied. While each of these biotic factors has traditionally been studied in isolation, emerging research consistently point to complex interwoven interactions between biotic and environmental factors.

Factors influencing undernutrition among children under 5 years from cocoa-growing communities in Bougainville.

Half the children under the age of 5 years in Papua New Guinea (PNG) are undernourished, more than double the global average with rural areas disproportionately affected. This study examines factors associated with stunting, wasting and underweight in cocoa growers' children (<5 years) in the Autonomous Region of Bougainville (ARoB), using data from a comprehensive 2017 cross-sectional livelihoods survey. Sixteen independent predictors for stunting, wasting and underweight were selected based on the UNICEF Conceptual Framework of Determinants of Undernutrition. We used multilevel logistic mixed regression models to measure the association of the explanatory variables with stunting, wasting and underweight. At the household level, the adjusted OR (aOR) of stunting (aOR=1.71,95% CI 1.14 to 2.55) and underweight (aOR=2.11, 95% CI 1.16 to 3.82) increased significantly among children from households with unimproved toilet facilities. The aOR for underweight also increased among children from households without access to clean drinking water (aOR=1.97, 95% CI 1.19 to 3.29). Short maternal stature was significantly associated with child stunting, the odds increased as maternal height decreased (from 150 to <155 cm, aOR=1.52, 95% CI 1.02 to 2.26) (<150 cm, aOR=2.37, 95% CI 1.29 to 4.35). At the individual level, the odds of a child being underweight increased with birth order (second born, aOR=1.92, 95% CI 1.09 to 3.36; third born, aOR=6.77, 95% CI 2.00 to 22.82). Compared with children less than 6 months, children aged 6-23 months and 24-59 months had a higher odds of being stunted (aOR=3.27, 95% CI 1.57 to 6.78 and aOR=2.82, 95% CI 1.40 to 5.67) and underweight (aOR=4.83, 95% CI 1.36 to 17.24 and aOR=4.59, 95% CI 1.29 to 16.26). No variables were found to be significant for wasting. Interventions that simultaneously target key life stages for women and children and the underlying social and environmental determinants are required for sustained improvements to undernutrition.

The extent to which the domestic conditions of cocoa farmers in Bougainville impede livelihoods.

BACKGROUND: Bougainville, an autonomous region of Papua New Guinea (PNG) is slowly improving services and infrastructure destroyed 20 years ago during the ten year civil war. However, the region still faces significant constraints to economic growth and human development and remains under-developed compared to PNG and close Pacific neighbours. PNG's 2017 Human Development Category (HDC) was one of the lowest at 0.544. The Bougainville Strategic Development Plan 2018-2022 noted significant gaps in health services and infrastructure, had inadequate water and waste disposal and experienced weak markets and cocoa quality. This research examines domestic conditions and the extent to which they impact on livelihoods. METHOD: A cross-sectional livelihood survey was administered to cocoa growing households in 33 Village Assemblies (VAs) with 11 VAs in each of the three regions. RESULTS: Data was collected from 5172 individuals. A significant majority of households reported multiple health issues, rudimentary housing, unimproved sanitation and unimproved water. Over two-thirds of cocoa growers did not sell any cocoa bags in 2014-2016 resulting in low incomes and greater food insecurity compared to families selling cocoa. Families that produced no saleable cocoa were more likely to have rudimentary housing, unimproved toilet facilities and unsafe water, factors that increase the likelihood of chronic disease and exacerbate malnutrition and poor labour productivity. CONCLUSION: This study provides key information about the health and livelihood status of cocoa growers in Bougainville. If productivity is to increase, farmer health needs to improve including improving water and sanitation practices and diets. Building a responsive health system for the community is a challenge when a majority of the population live in small villages with difficult access to health centres. Establishing and integrating outreach village health clinics will enable health care to be more accessible to these remote communities.

The effect of pre-industrial and predicted atmospheric CO2 concentrations on the development of diazotrophic and non-diazotrophic cyanobacterium: Dolichospermum circinale and Microcystis aeruginosa.

Photoautotrophs are capable of consuming high quantities of CO2, yet scant research exists examining the influence of different CO2 concentrations on the growth of freshwater diazotrophic or non-diazotrophic cyanobacteria. In this study, we cultured two cyanobacteria taxa (Dolichospermum circinale and Microcystis aeruginosa) within controlled atmospheric CO2 chambers at pre-industrial, and post-industrial concentrations. Biovolume and chlorophyll a (Chl-a) differed as a consequence of the adjusted CO2 gradients. Significantly higher biovolume measurements were observed in the elevated CO2 treatment for the diazotrophic species in the initial experiment. However, a follow-up experiment, with a corrected culture replenishment regime showed Chl-a measurements were greater for the diazotrophic and non-diazotrophic species in the elevated CO2 treatment. Increasing CO2 presents a risk to already compromised eutrophic and hyper-eutrophic ecosystems, and we reason increasing CO2 concentrations could affect photosynthetic performance and CO2 assimilation of surface dwelling cyanobacteria. Further experimental work is required to establish ecological thresholds for freshwater ecosystems, as pH levels showed a measurable reduction within the elevated CO2 treatments. As cyanobacteria species may respond quite differently to future CO2 concentrations similar comparative studies should be carried out that focus on CO2 dynamics and pH. The findings of the study indicate diazotrophic cyanobacteria growth in particular may benefit from elevated atmospheric CO2 concentrations.

Detecting the impact of land cover change on observed rainfall.

Analysis of observational data to pinpoint impact of land cover change on local rainfall is difficult due to multiple environmental factors that cannot be strictly controlled. In this study we use a statistical approach to identify the relationship between removal of tree cover and rainfall with data from best available sources for two large areas in Australia. Gridded rainfall data between 1979 and 2015 was used for the areas, while large scale (exogenous) effects were represented by mean rainfall across a much larger area and climatic indicators, such as Southern Oscillation Index and Indian Ocean Dipole. Both generalised additive modelling and step trend tests were used for the analysis. For a region in south central Queensland, the reported change in tree clearing between 2002-2005 did not result in strong statistically significant precipitation changes. On the other hand, results from a bushfire affected region on the border of New South Wales and Victoria suggest significant changes in the rainfall due to changes in tree cover. This indicates the method works better when an abrupt change in the data can be clearly identified. The results from the step trend test also mainly identified a positive relationship between the tree cover and the rainfall at p < 0.1 at the NSW/Victoria region. High rainfall variability and possible regrowth could have impacted the results in the Queensland region.

Phenotypic Variability Correlates with Clinical Outcome in Cryptococcus Isolates Obtained from Botswanan HIV/AIDS Patients.

Pathogenic species of Cryptococcus cause hundreds of thousands of deaths annually. Considerable phenotypic variation is exhibited during infection, including increased capsule size, capsule shedding, giant cells (≥15 µm), and micro cells (≤1 µm). We examined 70 clinical isolates of Cryptococcus neoformans and Cryptococcus tetragattii from HIV/AIDS patients in Botswana to determine whether the capacity to produce morphological variants was associated with clinical parameters. Isolates were cultured under conditions designed to simulate in vivo stresses. Substantial variation was seen across morphological and clinical data. Giant cells were more common in C. tetragattii, while micro cells and shed capsule occurred in C. neoformans only. Phenotypic variables fell into two groups associated with differing symptoms. The production of "large" phenotypes (greater cell and capsule size and giant cells) was associated with higher CD4 count and was negatively correlated with intracranial pressure indicators, suggesting that these are induced in early stage infection. "Small" phenotypes (micro cells and shed capsule) were associated with lower CD4 counts, negatively correlated with meningeal inflammation indicators, and positively correlated with intracranial pressure indicators, suggesting that they are produced later during infection and may contribute to immune suppression and promote proliferation and dissemination. These trends persisted at the species level, indicating that they were not driven by association with particular Cryptococcus species. Isolates possessing giant cells, micro cells, and shed capsule were rare, but strikingly, they were associated with patient death (P = 0.0165). Our data indicate that pleomorphism is an important driver in Cryptococcus infection.IMPORTANCE Cryptococcosis results in hundreds of thousands of deaths annually, predominantly in sub-Saharan Africa. Cryptococcus is an encapsulated yeast, and during infection, cells have the capacity for substantial morphological changes, including capsule enlargement and shedding and variations in cell shape and size. In this study, we examined 70 Cryptococcus isolates causing meningitis in HIV/AIDS patients in Botswana in order to look for associations between phenotypic variation and clinical symptoms. Four variant phenotypes were seen across strains: giant cells of ≥15 µm, micro cells of ≤1 µm, shed extracellular capsule, and irregularly shaped cells. We found that "large" and "small" phenotypes were associated with differing disease symptoms, indicating that their production may be important during the disease process. Overall, our study indicates that Cryptococcus strains that can switch on cell types under different situations may be more able to sustain infection and resist the host response.

Key Ecological Roles for Zoosporic True Fungi in Aquatic Habitats.

The diversity and abundance of zoosporic true fungi have been analyzed recently using fungal sequence libraries and advances in molecular methods, such as high-throughput sequencing. This review focuses on four evolutionary primitive true fungal phyla: the Aphelidea, Chytridiomycota, Neocallimastigomycota, and Rosellida (Cryptomycota), most species of which are not polycentric or mycelial (filamentous), rather they tend to be primarily monocentric (unicellular). Zoosporic fungi appear to be both abundant and diverse in many aquatic habitats around the world, with abundance often exceeding other fungal phyla in these habitats, and numerous novel genetic sequences identified. Zoosporic fungi are able to survive extreme conditions, such as high and extremely low pH; however, more work remains to be done. They appear to have important ecological roles as saprobes in decomposition of particulate organic substrates, pollen, plant litter, and dead animals; as parasites of zooplankton and algae; as parasites of vertebrate animals (such as frogs); and as symbionts in the digestive tracts of mammals. Some chytrids cause economically important diseases of plants and animals. They regulate sizes of phytoplankton populations. Further metagenomics surveys of aquatic ecosystems are expected to enlarge our knowledge of the diversity of true zoosporic fungi. Coupled with studies on their functional ecology, we are moving closer to unraveling the role of zoosporic fungi in carbon cycling and the impact of climate change on zoosporic fungal populations.