Discovery of probiotic bacteria from fish gut with potential for use in marine aquaculture

The aquaculture industry has been growing rapidly for the last 30 years. In the last decade marine aquaculture intensified because of increasing need to for fill the world’s protein requirements. In southern Europe the culture of sea bass (Dicentrarchus labrax), gilthead seabream (Sparus aurata) and sole (Solea Solea) are of great importance, while the culture of meagre (Argyrosomus regius) has been introduced in recent years. Accompanying the increase in intensive aquaculture is a concurrent increasing disease, which result in large economic losses. Vibrio anguillarum is a well characterised fish pathogen that causes acute haemorrhagic septicaemia and the control strategies currently employed include vaccination and chemotherapy (Austin and Austin, 2007). Common practice among fish farms is the use of antibiotics to prevent the spread of infection, but concerns regarding impact on the environment and human health have resulted in the search for new methods of controlling infection. To date a wide range of bacteria have been proposed for their application as probiotics (Kesarcodi-Watson et al., 2008: review), but not all potential probiotics are viable in reality, so the search continues.

Sorroza and colleagues (2012) isolated gut bacteria from sea bass, gilthead bream and sole for determination of probiotic potential. Gut samples were cultured and the antagonistic potential of the isolates was tested against 10 known pathogenic strains of V. anguillarum, V. aloginolticus, P. damselae, Yesina ruckeri, Lactococcus garvieae, streptococcus iniae and those with antagonistic effects were identified using 16s rRNA gene partial sequencing by BLAST analysis. To determine how the antagonistic isolates may interact in the gut their ability to adhere to gut mucus and grow was compared to pathogenic strain Vibrio anguillarum. The purpose of this was to see if the antagonistic strain could out compete the pathogenic strain for binding sites (competitive exclusion). The adherence potential was characterised by fluorescence of nucleic acid after staining with fluorescence protein. Adhered bacteria were measured after incubation and rinsing (to remove bacteria that had not adhered). After determination of antagonism and ability to survive in the gut, the isolates were added to feed to determine their action in live fish. Of the 50 strains that were isolated, only one strain, Vagococcus fluvialis, showed antagonistic effects against the pathogenic strains. Antagonistic effects were observed against V. anguillarum, P. damselae and Yersinia ruckeri. V. fluvialis showed a 10% reduction in the growth of V. anguillarum after 48h, but this was not significant. V. fluvialis showed significant adhesion to mucus compared to bovine serum albumin and polystyrene. In the competitive assay the adhesion capability of V. anguillarum was significantly reduced (54%) after exposure of intestinal mucus to the antagonistic strain. Addition of V.fluvialis to feed showed significant increases in survival of sea bass with addition of the probiotic, compared to V. anguillarum stresses fish.

V. fluvialis is a lactic acid bacteria, bacteria commonly used in probiotics. The study demonstrated well that competition for binding sites inhibits the ability of a pathogen to adhere. The authors describe the ability of V. fluvialis to outcompete V. anguillarum for binding sites, but not the possibility of the production of secondary metabolites as antimicrobials. This might be an interesting area to explore, if isolated; the compound could be added directly to the feed at lower concentrations. Function aside, V. fluvialis clearly serves its purpose. There is definitely potential here for V. fluvialis to become a major probiotic in marine aquaculture.        

Sorroza. L., Padilla.D., Acosta. F., Roman. L., Grasso. V., Vega. J., Real. F., (2012). Characterisation of the probiotic strain Vagococcus fluvialis in the protection of European sea bass (Dicentrarchchus labrax) against vibriosis by Vibrio anguillarum. Veterinary Microbiology. 155: 369-373.

Austin. B., Austin. D. A., (2007). Bacterial fish pathogens: Diseases of farmed and wild fish, 4^th (revised) ed. Spriger-Praxis, Godalming.

Diversity and dynamics of bacterial communities in coastal sands

Interactions between land, ocean and atmosphere allow for highly dynamic coastal ecosystems, with sands acting as filters and mediums in which a variety of materials accumulate. These interactions and accumulations make sands diverse habitats for microorganisms with many niches available and an ever-changing environment. It is thought that the dynamic nature of coastal sands results in high selection pressure from the environment, allowing only the best-adapted microorganisms to permanently establish themselves.

The authors of this paper (Gobet et al, 2012) set out to discover more about the dynamics of bacterial populations of coastal sands with particular emphasis on temporal fluctuations. Utilising pyrosequencing techniques of ribosomal genes, they examined the effects of a variety of environmental factors on the studied bacterial populations. Their study compared the similarity of bacterial community composition of communities from three coastal compartments, sand, pore water and the adjacent water column, sampled from the island of Sylt, Wadden Sea, Germany.

The key findings of their study were that there were a low proportion of shared bacterial populations (less than 0.2% between the pore water and the sand grains and also low between the sand and the water column, based on community composition and evenness) at the time of sampling. The sampled water column consisted mostly of Bacteroidetes and Alpha-/Gamma- Proteobacteria, with Verrucomicroba and Actinobacteria also representing a significant presence and the sand’s community consisted of mostly Bacteroidetes, Gammaproteobacteria, Deltaproteobacteria and Planctomycetes species both in accordance with previous research. The pore water had a similar composition to the sand with some temporal variation that was accounted for by exchange of land and marine microbial communities as a consequence of a constantly changing environment. A positive relationship between sediment depth and bacterial species richness, with the exception of Cyanobacteria and Bacteroidetes, was found at most of their sampling sites, an observation that was in agreement with prior research (Urakawa et al., 2000 and Böer et al., 2009b), and due to habitat stability.

Other findings include a high turnover of bacterial diversity in regards to sediment depth and time at OTU (phylum) level, indicating a highly dynamic community, with some seasonal fluctuations observed in abundant groups such as Gammaproteobacteria and Planctomycetes possibly due the changing spring weather (the sampling was carried out in March 2006, a period of turbulent conditions in the Wadden Sea) and 50% of bacteria present at all times in all three depths of sand were Gammaproteobacteria and Deltaproteobacteria, representing 23% and 10% of total sand cell counts. 40% of the total OTU cell counts, the rare biosphere, only appeared once per sample, and represented a large fraction of the community that may be subject to substantial change. They concluded that a large turnover of the bacterial community composition could be due to a variety of factors including migration, complexity of environment, rare species becoming dominant in suitable conditions (i.e. the seed bank hypothesis) and extracellular DNA having an effect on their results. Community composition was found to be more varied than microbial functions such as biomass and extracellular enzyme activities, indicating that resident species are responsible for these functions and the rare biosphere has little effect.

Although comprehensive in their approaches, the main issue I had with the study was their limited sampling time, which was around a year. This meant that the data set acquired from their sampling (they had included some previous long term data) only represents the community structure of Sylt’s coastal sands for that year, not taking into account variations over longer time periods, especially when it comes to the highly variable nature of Northern European seasons. Also their molecular techniques didn’t differentiate DNA originating from living populations and extracellular DNA, the presence of which may have skewed their results, but they argue any effect from this DNA was probably negligible.

The authors identified areas for further study in to bacterial populations including research into a discrepancy between the temporal dynamics of communities in sediments and water columns, which had been shown to be seasonally cyclic and further research into the response of the rare biosphere to the environment.

Reference        

Gobet A, Böer SI, Huse SM, Beusekom JE, Quince C, Sogin ML, Boetius A and Ramette A (2012) Diversity and dynamics of rare and of resident bacterial populations in coastal sands The ISME Journal, 6, 542–553.

What Makes Bacteria “Friendly”?

Marine aquaculture, as a sector, is constrained by disease. Rearing animals in high stock densities increases the likelihood of colonisation by pathogenic bacteria, and therefore disease, which can have huge economic repercussions. One explicit example of the economic costs of disease in marine aquaculture is in Norway where, to date, over US$77 million has been spent on the management of fish disease. In the past decade there has been an intensive development in probiotics for aquaculture to reduce the incidence of disease, as well as other benefits such as increased growth rate. By definition, probiotics are “living bacteria that stably colonize the guts of animals with a positive impact on the health of the host.” Whilst research efforts in probiotics have increased, the mechanisms in which probionts reduce pathogeneity are still poorly understood. In the reviewed paper, Rendueles et al. (2012) used the zebrafish (Danio rerio) model system to better understand the molecular mechanisms with confer host advantage for various potential probiotics.

Rendueles et al. (2012) raised germ free zebrafish larvae for use in all their experiments. Firstly Edwardsiella ictaluri was identified as a virulent bacterial strain which induced a strong inflammatory response and rapid mortality. Using E.ictaluri as a pathogenic challenge, the authors investigated the action of 37 potential probiotic bacteria strains which were selected for experimental use as they are widely exploited as probiotics in food and aquaculture industries. Zebrafish larvae were pre-cultured with the potential probiotics prior to initiation of the pathogenic challenge, pre-colonized treatment mortality rates were then compared to pathogen only controls; from this experiment three protective probionts were identified. One strain which provided significant protection against the pathogen challenge was Escherichia coli MG1655 and it was therefore investigated further to better understand the mechanisms in which it provided protection. Experiments were conducted which convincingly ruled out direct toxicity to pathogen and immune system activation as mechanisms. Importantly, E.coli MG1655 is a biofilm forming bacterium, and therefore authors hypothesised that the mechanism of protection could be adhesion and competition for space with the pathogen. To test this hypothesis zebrafish were pre-cultured with a mutant E.coli MG1655 strain which had type 1 fimbriae (adhesion organelles) knocked-out, the type 1 fimbriae deficient mutants had an impaired ability to confer protection against the pathogenic challenge.

The reviewed paper has made an important step forward in understanding the molecular mechanisms in which probionts provide protection against pathogens. Not only has the paper made an interesting finding about the importance of adhesion factors in pathogen protection, it also provides a novel system in which to study probiotic protection mechanisms, and host-pathogen interactions per se. I believe that unpicking host-microbe interactions is important for a wide range of biological fields, including evolutionary theory (See Matt’s Creator of Species Blog on the hologenome); however there are also clear economic applications for the use of probiotics in aquaculture.

Rendueles, O., Fre, M., Be, E., Herbomel, P., Ferrie, L., Levraud, J., & Ghigo, J. (2012). A New Zebrafish Model of Oro-Intestinal Pathogen Colonization Reveals a Key Role for Adhesion in Protection by Probiotic Bacteria, PlosPathogens, 8(7).

http://www.plospathogens.org/article/info%3Adoi%2F10.1371%2Fjournal.ppat.1002815

 

 

Obligate oil-degrading marine bacteria

This paper, by Yakimov et al. (2007), is a review of the latest results relating to the biogeography, ecophysiology, genomics and potential for biotechnological applications of obligate hydrocarbonoclastic bacteria (OHCB). These bacteria are a group of marine hydrocarbon-degrading bacteria which have been shown to play a significant role in the biological removal of petroleum hydrocarbons from polluted marine water.

A number of oil-degrading bacteria have been isolated but less than a quarter have been obtained from marine sources. Nineteen genera of Eubacteria have been characterised as indigenous marine organisms. Two strains of the Firmicutes and Bacteroidetes phyla have been isolated. The remaining aerobic marine hydrogen-degrading isolated are associated with α- or the γ-Proteobacteria subclasses. The first OHCB to be described was Alcanivorax borkumensis. Since then others have been described which include; A. borkumensis, A. jadensis, A. dieselolei, C. pugetii and C. oligotrophus.

At the end of 2006, more than 250 Alcanivorax-affiliated bacteria had been isolated in all types of marine environments: surface water, sediments, hydrothermal vents and mud volcanoes, shallow and deep sea water bodies, ridge flank crustal fluid and grey whale carcasses. The temperature in which OHCB’s can survive varies with the different strains. T. oleivorans and Cycloclasticus spp. are widely distributed in the Northern hemisphere. The distribution of the psychrophilic OHCB Oleispira antartica is thus far limited to colder waters.

Organisms genetically analysed so far exhibit features typical of oligotrophic bacteria. The most detailed study took place on C. oligotrophus. The cytoplasm was shown to be very dilute, with a dry mass per cell 7-8 times lower than that of Escherichia coli. The outer cellular membrane is enriched for a wide range of transport systems for the capture of nutrients and diverse oligo-elements from the generally nutrient-poor environment.

An influx of oil in marine sites causes population densities of OHCB to increase by up to 90%, with aliphatic hydrocarbon-degraders being the first to bloom. This is followed by microbes (in particular Cycloclasticus spp.) which are specialised for the remaining compounds which are more difficult to degrade.

Marine hydrocarbon-degrading microorganisms can efficiently degrade hydrocarbons and so can be used in oil spills. However more knowledge is needed on the critically important activities and roles of predators and grazers on the composition population dynamics and ecophysiological functioning of marine oil-degrading communities. OHCBs have been shown to have a degrading effect on PHAs. The recent discovery of OHCBs means that their enzyme repertoires are so far incomparable. They do have the potential in biocatalysis, the enzymatic biosynthesis of fine chemicals and added value compounds. Some novel enzymes have been retrieved as a result of a metagenome expression library of crude-oil enrichment, functional screening of the library resulted in the identification of five groups of carboxylhydrolase. All retrieved enzymes were characterised biochemically and exhibited good potential for biosynthetic applications.

Overall, more research needs to go into OHCBs in order to discover their full potential. This is a good paper as it brings together lots of studies and identifies key features regarding OHCBs.  

Yakimov M.M, Timmis K.N, and Golyshin P.N. 2007. ‘Obligate oil-degrading marine bacteria’. Current Opinion in Biotechnology. 18 (3). 257-266.

Effects of addition of 2 lactic acid bacteria on the development and conformation of sea bass larvae (Dicentrarchus labrax) and the influence on these microbiota

Developmental bone conformation problems such as spinal/skeletal deformities cause considerable issues for fish hatcheries. It is suspected that many of these deformities are caused by environmental, genetic or nutritional factors. Consequently it is important to research ways to limit development of these problems. Use of probiotics has been proposed as a possible means to reduce such deformities. Previous studies looking at use of lactic acid bacteria as a probiotic have shown that they are useful to reduce some causes of skeletal deformation in certain fish species. The mode of this interaction is not yet clearly understood and may be indirect but arise due to reduced numbers of pathogenic bacteria or reduction of inflammation of the larvae which may contribute to the risk of deformation. 

Lamari et al. (2013) aimed to study the effects of two strains of lactic acid bacteria; Pediococcus acidilactici and a strain of Lactobacillus casei on gene expression, associated microbiota and larval development. These strains of lactic acid bacteria were chosen because previous studies recommended that bacteria were chosen from the local environment or from the host to be used in the environment to improve potential for colonization. The bacteria were administered at 10⁶ and 10⁷ CFUs in two consecutive experiments. The 10 fold increase was decided on for the second experiment to boost the level of lactic acid above the detection threshold. There were three dietry groups; C which was the control, P had added Pediococcus acidilactici   and L had added Lactobacillus casei.

In both experiments growth of larvae was promoted by the addition of the bacteria but there was no significant difference in the number of spinal deformities between the control and experimental groups but significantly more spinal deformities were observed in group L than P.  Mineralization was delayed in group P but was overcome by most fish. Osteocalcin, a marker of ossification (the laying down of new bone material) was over expressed in group L. It can be concluded from these results that both types of bacteria influenced bone mineralization in different ways.

Counts of lactic acid bacteria remained low in both experiments therefore it can be inferred that dietary addition of the two strains of lactic acid bacteria does not lead to gut colonization. The fact that the dose was changed between the two experiments may be responsible for some of the differences observed between the experiments as dose is an important factor to consider when looking at the efficiency of probiotics.

This experiment confirmed use of Pediococcus acidilactici imporved skeletal conformation but the mode mode of action is still unclear. Ca conclusion cannot be made on the hypothesis of inflammation reduction because more observations and further work are needed to come to a conclusion.

Overall I found this paper quite interesting, it was easy to follow and I feel that its results form a basis for a lot of future work as it shows that probiotics are not only useful for growth but also some may have properties which may help to reduce skeletal bone deformation.

Lamari F, Castex M, Larcher T, Ledevin M, Mazura D, Bakhrouf A, Gatesoupe F. 2013. Comparison of the effects of the dietary addition of two lactic acid bacteria on the development and conformation of sea bass larvae, Dicentrarchus labrax, and the influence on associated microbiota.  Aquaculture 376-379; 137-145. 

Ciguatera Fish Poisoning (CFP) and the examination of the epiphytic nature of Gambierdiscusn toxicus, a dinoflagellate involved in CFP

Ciguatera Fish Poisoning (CFP) is potentially a global health problem; extensive international exchange of frozen fish have resulted in global cases of CFP. The causative poison: Ciguatoxin (CTX) is acquired by humans through the consumption of contaminated seafood (Friedman et al. 2008). The toxin is heat-stable when exposed to conventional cooking temperatures. It is also tasteless and odorless. The absence of prompt clinical testing has stemmed interesting detection methods, which have been used by some tropical Islanders. A quote from “Folk remedies for tropical fish poisoning in the Pacific” by Lobel. 1979, tells of the numerous and some quite humorous antidotes used by the native islanders.

“(1) cooking the fish with a silver object to see if discoloration results, (2) seeing if the fish repels flies or ants, (3) avoiding sliced fish that fails to reflect a rainbow when held to the sun, (4) rubbing one’s gyms with the liver to see if a tingling results, and (5) giving a sample of the questionable fish to a household pet or an elderly relative as a bioassay…”

The toxin CFX originates in the dinoflagellate Gambierdiscus spp (Friedman et al. 2008). These have been found in association with various macroalgae that live within coral reef ecosystems. Herbivorous fish consume these dinoflagellates through grazing, initiating the process of bioaccumulation and biomagnification up through the food web. Parsons et al. 2011, examined the interaction between Gambierdiscus toxicus cells and 24 macroalgal hosts, with the intention to better document and understand the relationship between the toxin producing epiphytic dinoflagellate and potential algal hosts.

24 samples of macroalgae were collected from coastal waters at Leleiwi Park in Hilo, Hawaii. Algal specimens were identified. The samples were cleaned with filtered seawater, removing detritus and epiphytes. 100g (wet weight) of each sample were placed respectively into Petri dishes containing 10ml of Keller’s medium. 0.1 ml aliquots of G. toxicus BIG12 were added to each sample (approximately 100 cells per Petri dish). The Gambierdiscus cells were counted immediately after manipulation and then: two, 16, 24 and every 24-72 hours thereafter. Observations were recorded within classes: ‘alive and attached/in contact with host’, ‘alive but unattached’ and ‘dead’. The experiment was conducted over a 29-day period.

Parson et al. 2011 converted the data classes into relative abundance values; i.e. % of total cells alive and attached. Within the experiment there were cases where counts were missing for some Petri dishes, Parson et al. 2011 state: “the missing points were extrapolated using previous and subsequent days” in the write up it is discussed that this is less than optimal but required so as to allow for subsequent statistical analysis. However, the reasoning as to why there were “missing counts” was very ambiguous! I’m guessing that it’s due to human error when conducting the experiment! This is less than desirable, but the error has been acknowledge and if occurred in, as stated a “few cases”, the effect on the results should be minimal. For all statistical tests PRIMER 6 was used. A Bray-Curtis similarity index was carried out to group/“cluster” together the different algal hosts based on the three parameters: % alive and attached, % alive and unattached and % dead. Similarity profile permutation test (SIMPROF) were used to assess significant differences between “clusters”. These host species could be categorized into 14 significantly different groups. In terms of the epiphytic nature of the Gambierdiscus toxicus, the cells would not attach to the group containing these algal species: Bryopsis sp. and Portieria hornemannii (Group A), but did attach to other species: Dasya sp., Siphonous sp., Acanthophora spicifera, Amansia glomerata, Centroceras sp., Ceramium sp., Chaetomorpha sp., Dudresnaya sp., Jania sp., Tolypiocladia glomerulata and Turbinaria ornate. However, these results obtained differ to a previous study by Grzebyk et al. 1994, in which P. hornemannii was found to stimulate Gambierdiscus growth, not inhibit it. Conflicting results could be due to differences in the algal host condition: health and age of specimen and differences in the species of Gambierdiscus used for the investigations. 

One of the most important findings was the indication that Gambierdiscus Toxicus may change from being in an epiphytic state to free-swimming: in response to a change in the chemical environment around/on the host’s surface. Cell attachment and detachment were evident in the algal host Siphonous sp. and in several other species, some of which were: Dasya sp. and Martensia fragilis. Where Gambierdiscus was observed to change it's 'behaviour', the algal hosts were found to be producing chemical defences against herbivory, releasing chemical cues affecting the dinoflagellates.  

Ciguatera Fish Poisoning (CPF) is particularly interesting due to the perplexing symptoms; which can be bouts of recurring neurological disorders, affecting sufferers for a lifetime. I selected this paper because I wanted to explore an instigating factor behind the phenomenon of CPF: the dinoflagellate Gambierdiscus toxicus. The research carried out by Parson et al. 2011, relates to Randall’s new surface theory (Randall. 1958): which states that ‘newly denuded coral surface will be colonized by opportunistic algae’. Due to environmental changes: coral bleaching incidents are believed to be on the rise. Outbreaks of CFP could potentially become more frequent. Therefore it may be beneficial to further investigate the conditions that lead Gambierdiscus toxicus to change between stages of epiphytic and planktonic. This may yield more information as to what conditions affect dinoflagellate growth and possibly allow dinoflagellate ‘blooms’ to be anticipated.

Parson, M. L., Settlemier, C.J. and Ballauer, J. M. (2011)

"An examination of the epiphytic nature of Gambierdiscus toxicus, a dinoflagellate involved in ciguatera   fish poisoning"

  

Harmful Algae, 10: 598-605.

 http://www.ncbi.nlm.nih.gov/pubmed/21966283

Friedman, M. A., Fleming, L. E., Fernandes, M., Bienfang, P., Schrank, K., Dickey, R., Bottein, M. Y., Backer, L., Ayyar, R., Weisman, R., Watkins, S., Granade, R. and Reich, A. (2008)

"Ciguatera Fish Poisoning: Treatment, Prevention and Management"

Mar. Drugs, 3: 456-479.   

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2579736/

Lobel, P. S. (1979)

"Folk remedies for tropical fish poisoning in the Pacific"

Sea Frontiers, 25: 239-245.

Randall, J.E. (1958) 

"A review of ciguatera, tropical fish poisoning with a tentative explanation of its cause"

Bull. Mar. Sci. Gulf Carib. 8: 236–267.

Early warning systems for Vibrio disease risks

Craig Baker-Austin gave a very interesting talk at PML this week, where he described evidence for emerging Vibrio risk at high latitudes in response to ocean warming. Several previous posts have covered similar topics:  Oliver wrote about Vezzulli et al.’s (2012) paper in the blog ‘Evidence from the Vibrios as to the effects that ocean warming has on the prokaryotic community’, Sophie reviewed Schets et al.’s paper (2011) in her blog ‘Potentially Human Pathogenic Vibrios in Marine and Fresh Bathing Waters Related to Environmental Conditions and Disease Outcome’, and finally Harri’s ‘Microbes on the March’ on Langer et al. (2013) describes shifts in distribution ranges due to temperature increases. Together these papers illustrate how temperature changes can influence distribution ranges of organisms with potential impacts on human health.

Baker-Austin et al. (2013) used multidecadal long-term sea surface temperature data sets from the Baltic Sea in combination with reports of Vibrio infections in northern Europe to study the correlation between temperature increases and Vibrio diseases. In fact, vibrios grow preferentially in warm (> 15°C), low-salinity (< 25 ppt NaCl) sea water, which is why the Baltic Sea provides a particularly interesting regions to study emerging Vibrio disease, as it forms one of the largest low-salinity marine ecosystems on Earth as well as having the fastest net SST warming trend of any large marine ecosystem between 1982 and 2007. They showed that maximum annual SST showed a very strong association with the number of Vibrio cases reported, as especially during years with extreme warm summers (1994, 2003, and 2006) an unusually high number of Vibrio-associated wound infections and fatalities were reported.  While not per se evidence for a causal link between temperature and Vibrio infections, some biologically plausible explanations support this idea: high temperatures increase bacterial replication, Vibrio vulnificus abundance peaks at > 19°C, regulation of pathogenic competence of some Vibrio species may be temperature mediated, and of course, the increased risk resulting from higher use of coastal waters for leisure activities with higher temperatures (during summer).

However, models showed that SST alone could only predict about half of the reported Vibrio cases, while models including both SST and time substantially improved the accuracy, predicting around 70% of the cases from 2006. The time component could be the result of increased awareness of Vibrio infection over time or increased exposure due to shifts in population density along coastal areas. Overall it shows that sea surface temperature can be used as predictor to identify areas at high risk, but additional unknown factors still remain to be explained to increase accuracy of models.

Baker-Austin et al., (2012). provide strong evidence that SST can be used as a predictor of risk for high abundance of pathogenic vibrios. They predict a northward shift of the areas of maximum risk of infection in the Baltic according to the model and expected warming rates in the Baltic Sea. Personally I find the proposition of an early warning system to forecast the health risks of Vibrio disease by creating risk maps based on near-real-time remote sensing data most interesting. These maps would then be made available to the public to prevent infections and fatalities; maybe one day we will have a map showing risk of Vibrio disease just after the weather forecast!

Craig Baker-Austin had some neat animations of those risk maps in his presentations, but I couldn’t find them online. But the supplementary material for this article shows some maps (3S) from remote sensing data in 2006 and risk maps for the Baltic Sea (4S).

Baker-Austin, C., Trinanes, J. a., Taylor, N. G. H., Hartnell, R., Siitonen, A. & Martinez-Urtaza, J. 2012. Emerging Vibrio risk at high latitudes in response toocean warming. Nature Climate Change, 3, 73–77.

Supplementary material: http://www.nature.com/nclimate/journal/v3/n1/extref/nclimate1628-s1.pdf

Also interesting: www.coastalWarming.com, a compilation of temperature maps.