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Ice machines can harbor water-related organisms, and the use of ice or tap water for clinical care activities has been associated with infections in health care settings. During 2021–2022, a total of 23 cases of infection by Burkholderia multivorans (sequence type ST659) were reported at two southern California hospitals and linked to contaminated ice and water from ice machines. In addition to these 23 cases, this report also includes 23 previously unreported cases of B. multivorans ST659 infections that occurred during 2020–2024: 13 at a northern California hospital, eight at a hospital in Colorado, and two additional cases at one of the southern California hospitals. The same brand of ice machine and brands of filters, descaling, and sanitizing products were used by all four hospitals; B. multivorans was isolated from samples collected from ice machines in two of the hospitals. Whole genome sequencing indicated that all clinical and ice machine isolates were highly genetically similar (0–14 single nucleotide variant differences across 81% of the selected reference genome). Recommendations from public health officials to halt the outbreak included avoiding ice and tap water during clinical care activities. An investigation is ongoing to determine possible sources of ice machine contamination. During outbreaks of water-related organisms in health care facilities, health care personnel should consider avoiding the use of tap water, including ice and water from ice machines, for patient care. [ABSTRACT FROM AUTHOR]

Paradana is one of the biggest ice caves in Slovenia, with an estimated ice volume of 8,000 m3. Reflecting climatological conditions, the cave ice undergoes repeated freeze-thaw cycles and regular yearly deposition of fresh ice. Three distinct ice block samples, collected from the frozen lake in May 2016, were analysed to obtain data on ice physicochemical properties and the composition of associated microbiota. Isotopic composition of the ice samples (18O, 2H) and a local meteoric water line (LMWL) constructed for monthly precipitation at Postojna were used to estimate the isotopic composition of the water that formed the ice, which had high values of deuterium excess and low concentrations of chloride, sulphate and nitrate. The values of total organic carbon (1.93–3.95 mg/l) within the ice blocks fall within the range of those measured in karst streams. Total cell count in the ice was high and the proportion of cell viability increased along the depth gradient and ranged from 4.67 × 104 to 1.52 × 105 cells/ml and from 51.0 to 85.4%, respectively. Proteobacteria represented the core of the cave-ice microbiome (55.9–79.1%), and probably play an essential role in this ecosystem. Actinobacteria was the second most abundant phylum (12.0–31.4%), followed in abundance by Bacteroidetes (2.8–4.3%). Ice phylotypes recorded amounted to 442 genera, but only 43 genera had abundances greater than 0.5%. Most abundant were Pseudomonas, a well-known ice dweller, and Lysobacter, which previously was not reported in this context. Finally, two xanthophytes, Chloridella glacialis and Ellipsoidion perminimum, known from polar environments, were cultured from the ice. This indicates that the abundance and ecological role of phototrophs in such environments might be greater than previously deduced. [ABSTRACT FROM AUTHOR]

The article discusses the cause of the oceanic algal bloom in the Arctic region. It states that the ice and melt conditions increase growth of Arctic phytoplankton and increase net primary productivity (NPP). It mentions that the role of nutrients also should be taken into account for the development of the algal bloom.

Polar Oceans are natural CO2 sinks because of the enhanced solubility of CO2 in cold water. The Arctic Ocean is at additional risk of accelerated ocean acidification (OA) because of freshwater inputs from sea ice and rivers, which influence the carbonate system. Winter conditions in the Arctic are of interest because of both cold temperatures and limited CO2 venting to the atmosphere when sea ice is present. Earlier OA experiments on Arctic microbial communities conducted in the absence of ice cover, hinted at shifts in taxa dominance and diversity under lowered pH. The Catlin Arctic Survey provided an opportunity to conduct in situ, under-ice, OA experiments during late Arctic winter. Seawater was collected from under the sea ice off Ellef Ringnes Island, and communities were exposed to three CO2 levels for 6 days. Phylogenetic diversity was greater in the attached fraction compared to the free-living fraction in situ, in the controls and in the treatments. The dominant taxa in all cases were Gammaproteobacteria but acidification had little effect compared to the effects of containment. Phylogenetic net relatedness indices suggested that acidification may have decreased the diversity within some bacterial orders, but overall there was no clear trend. Within the experimental communities, alkalinity best explained the variance among samples and replicates, suggesting subtle changes in the carbonate system need to be considered in such experiments. We conclude that under ice communities have the capacity to respond either by selection or phenotypic plasticity to heightened CO2 levels over the short term. [ABSTRACT FROM AUTHOR]

Nitrogen inputs and microbial nitrogen cycling were investigated along a 79 km transect into the Greenland Ice Sheet (GrIS) during the main ablation season in summer 2010. The depletion of dissolved nitrate and production of ammonium (relative to icemelt) in cryoconite holes on Leverett Glacier, within 7.5 km of the ice sheet margin, suggested microbial uptake and ammonification respectively. Positive in situ acetylene assays indicated nitrogen fixation both in a debris-rich 100 m marginal zone and up to 5.7 km upslope on Leverett Glacier (with rates up to 16.3 µmoles C2H4 m-2 day-1). No positive acetylene assays were detected > 5.7 km into the ablation zone of the ice sheet. Potential nitrogen fixation only occurred when concentrations of dissolved and sediment-bound inorganic nitrogen were undetectable. Estimates of nitrogen fluxes onto the transect suggest that nitrogen fixation is likely of minor importance to the overall nitrogen budget of Leverett Glacier and of negligible importance to the nitrogen budget on the main ice sheet itself. Nitrogen fixation is however potentially important as a source of nitrogen to microbial communities in the debrisrich marginal zone close to the terminus of the glacier, where nitrogen fixation may aid the colonization of subglacial and moraine-derived debris. [ABSTRACT FROM AUTHOR]

Abstract: Ice melt water from a 22.27 m ice core which was drilled from the East Rongbuk Glacier, Mt. Everest was incubation in two incubation ways: plate melt water directly and enrichment melt water prior plate, respectively. The abundance of cultivable bacteria ranged from 0–295 CFU mL−1 to 0–1720 CFU mL−1 in two incubations with a total of 1385 isolates obtained. Comparing to direct cultivation, enrichment cultivation recovered more bacteria. Pigment-producing bacteria accounted for an average of 84.9% of total isolates. Such high percentage suggested that pigment production may be an adaptive physiological feature for the bacteria in ice core to cope with strong ultraviolet radiation on the glacier. The abundances of cultivable bacteria and pigment-producing isolates varied synchronously along depth: higher abundance in the middle and lower at the top and bottom. It indicated that the middle part of the ice core was hospitable for the microbial survival. Based on the physiological properties of the colonies, eighty-nine isolates were selected for phylogenetic analysis. Obtained 16S rRNA gene sequences fell into four groups: Firmicutes, Alpha-Proteobacteria, Gamma-Proteobacteria, and Actinobacteria, with the Firmicutes being dominant. Microbial compositions derived from direct and enrichment cultivations were not overlapped. We suggest that it is a better way to explore the culturable microbial diversity in ice core by combining the approaches of both direct and enrichment cultivation. [Copyright &y& Elsevier]

Background. This study investigates the viable persistence of avian influenza viruses (AIVs) in various types of artificially frozen environmental water and evaluates the feasibility of similar occurrence taking place in nature, and allowing for prolonged abiotic virus survival, with subsequent biotic viral recirculation. Methods. Fresh, brackish, and salty water, taken in Japan from aquatic biotopes regularly visited by migratory waterfowl, were seeded with AIVs.Wemonthly monitored the viability of the seeded viruses in the frozen state at -20°C and -30°C, for 12 months. We also monitored virus viability following repeatedly induced freezing and thawing. Results. The viruses exhibited considerable viable persistence all along that period of time, as well as during freezing thawing cycles. Appreciable, yet noncrucial variances were observed in relation to some of the parameters examined. Conclusions. As typical waterborne pathogens of numerous northerly aquatic birds, AIVs are innately adapted to both the body temperature of their hosts (40°C to 42°C) and, presumably, to subzero temperatures of frozen lakes (down t-54°C in parts of Siberia) occupied and virus-seeded by subclinically infected birds, prior to freezing. Marked cryostability of AIVs appears to be evident. Preservation in environmental ice has significant ecophylogenetic and epidemiological implications, potentially, and could account for various unexplained phenomena. [ABSTRACT FROM AUTHOR]

Abstract: This paper reviews the utility of analog environments in preparations for a Europa lander mission. Such analogs are useful in the demonstration and rehearsal of engineering functions such as sample acquisition from an icy surface, as well as in the exercise of the scientific protocols needed to identify organic, inorganic and possible biological impurities in ice. Particular attention is drawn to Antarctic and Arctic analog sites where progress in these latter areas has been significant in recent years. [Copyright &y& Elsevier]

The article discusses bacteria. The author notes that bacteria are abundant and have unforeseen capabilities and that he was thrilled to be able to write about two types of bacteria that he thinks are of particularly interesting which are eubacteria and archaea. He presents a brief overview of some terminology regarding the origin of the word bacteria and a brief background on eubacteria and archaea. In-depth discussions on several types of eubacteria and archaea, which includes information on the environments where they can be found are presented, including mineral-loving bacteria, such as acidophiles, thermophiles, which live in the hydrothermal vents in the deep ocean, and those that live under ice sheets in the Arctic and Antarctica regions.

A study was conducted to evaluate the microbiological and chemical characteristics of ice collected from a commercial poultry further processing facility. During each of 3 visits, the following ice samples were collected: 1) freshly prepared, unused ice; 2) product-contact ice from ice-packed poultry parts; 3) product-contact ice from ice-packed poultry that had been visibly inspected and condemned as not for reuse; and 4) product-contact ice from ice-packed poultry that had passed visible inspection and had been prepared for reuse by washing (rinse with potable water and drain). The overall pattern for lowest to highest numbers of total aerobic microorganisms, coliforms, Escherichia coli, and Enterobacteriaceae was as follows: unused ice < washed ice < product-contact ice < condemned ice. Mean levels of total aerobic microorganisms, coliforms, and Eriterobacteriaceae in the unused ice were 0.3, 0.4, and 0.4 log10 cfu/mL, respectively. No E. coli was detected in the unused or washed ice, and levels were 0.5 and 1.5 log10 cfu/mL in the product-contact and condemned ice samples, respectively. Mean levels of bactena enumerated in condemned ice were 0.8, 1.0, and 0.6 log10 cfu/mL higher than the levels of bacteria found in product-contact ice for coliforms, E. coli, and Enterobacteriaceae, respectively. Washing and draining the product-contact ice decreased counts by 0.9, 0.7, 0.5, and 1.7 log10 cfu/mL for total aerobic microorganisms, coliforms, E. coli, and Enterobacteriaceae, respectively. All of the ice samples had similar pH values (pH 6.1 to 6.4). Unused and washed ice were not significantly different for total solids, total suspended solids, total Kjeldahl nitrogen, and chemical oxygen demand. Condemned ice contained the highest concentration of total solids, total suspended solids, total Kjeldahl nitrogen, and chemical oxygen demand, with levels more than 3 times that found in product contact ice. Data from the present study demonstrate that visible contamination in ice corresponds with increased microbiological and chemical contamination. Product-contact ice may be washed and the washing procedure can reduce the bacterial, solids, nitrogen, and organic loads. [ABSTRACT FROM AUTHOR]

The martian polar caps are among the most dynamic regions on Mars, growing substantially in winter as a significant fraction of the atmosphere freezes out in the form of CO2 ice. Unusual dark spots, fans and blotches form as the south-polar seasonal CO2 ice cap retreats during spring and summer. Small radial channel networks are often associated with the location of spots once the ice disappears. The spots have been proposed to be simply bare, defrosted ground; the formation of the channels has remained uncertain. Here we report infrared and visible observations that show that the spots and fans remain at CO2 ice temperatures well into summer, and must be granular materials that have been brought up to the surface of the ice, requiring a complex suite of processes to get them there. We propose that the seasonal ice cap forms an impermeable, translucent slab of CO2 ice that sublimates from the base, building up high-pressure gas beneath the slab. This gas levitates the ice, which eventually ruptures, producing high-velocity CO2 vents that erupt sand-sized grains in jets to form the spots and erode the channels. These processes are unlike any observed on Earth. [ABSTRACT FROM AUTHOR]

Presents research which studied microzones in the permanent ice covers of Antarctic lakes in the McMurdo Dry Valleys. Source of liquid water inclusions; Microbial consortium among ice sediment particles; Life capabilities of the consortium.

Certain organisms nucleate the crystallization of ice. This requires a small volume of water to be induced, probably by lattice-matching with a solid template, to form an 'ice embryo' -- a region sharing at least some of the characteristics of macroscopic ice. It is of particular interest to understand the structure and function of biological structures capable of lattice-matching (or otherwise inducing a quasi-crystalline state). Some strains of the Gram-negative eubacterial genera Erwinia, Pseudomonas, and Xanthomonas, and the mycobionts of certain lichens, display ice-nucleating activity. In bacteria, the activity is conferred by a protein that contains three nested periodicities of repetition, which probably reflects a hierarchy of three motifs of structural repetition. Thus the tertiary structure of the ice-nucleation protein is likely to be regular, consistent with the expectation of its forming a template for lattice-matching. Even within a clonal culture, the nucleating sites formed by bacteria and lichens vary considerably in the threshold temperatures at which they display activity; this indicates wide variations in either the size of the template, or its structural regularity, or both. However, ice-nucleating sites of lichen and bacterial origin are clearly differentiated by their sensitivities to experimental treatments. [ABSTRACT FROM AUTHOR]

Reports on the discovery of frozen bacteria in an ice core drilled from an Antarctic lake. Relation with the proteobacteria and actinomycetes microbes; Estimated age of microbes; Hypothesis on the origin and cause of freezing; Similarity of conditions with Jupiter's moon and Europa.

Describes research which discovered thriving microbes in the permanent ice layer of lakes in the Antarctic McMurdo Dry Valleys. Temperatures involved; Research by Priscu et al in this issue; Example of the adaptation of microorganisms to environmental extremes; How there can be life in icy ecosystems; Comparison with freshwater ice systems; Bacterial activity in freezing conditions; Value of studying cold life.