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A new study led by researchers at the University of Maryland, US, and the University of Genoa, Italy, reveals that there is a link between climate change and waterborne food poisoning: the rising temperature of seawater is causing warmth-loving Vibrio bacteria to multiply faster. Vibrio species are often linked to illnesses stemming from undercooked seafood and ingesting contaminated water. The research team found that outbreaks were not only occurring in the warmer waters of the US, but also now in Alaska, where people were eating infected local oysters. Although the trend was previously suspected, the study now confirms a direct link between the rising global climate and increased Vibrio infections, thanks to a 50-year collection of data reports.

Not only have scientists from the University of Alabama at Birmingham, US, found that babies’ airways are already colonised by bacteria before birth, the team has also found a potential link between this colonisation and severe respiratory problems up to a month post-birth. Collecting trachea samples from newly-delivered babies, the researchers noticed that infants that developed a chronic lung disease – called bronchopulmonary dysplasia (BPD) – were born with a much less diverse community of bacteria in their airways than both full-term and pre-term babies who did not develop respiratory issues. The study also suggests that the increased number of Lactobacillus bacteria in the infants’ airways may be involved in protecting against disease and lung development, as the children with lower numbers of the bacteria were more prone to BPD. These findings could lead the way for more research into the use of respiratory prebiotics.

A new strain of Clostridium difficile – a bacterium that can cause severe diarrhoea – has been increasingly more problematic in US hospitals than other strains. Only now, researchers at the University of Virginia, USA, have been able to explain how it is more lethal than normal strains: this novel strain produces a toxin that kills the protective cells, or eosinophils, in the human gut. This then allows the C. difficile strain to spread and cause inflammation through the rest of the body. However, all is not lost – knowing how it infects means that the research team can look for ways to stop it. In lab tests, replacing depleted eosinophils with those from a mouse appeared to render the molecule harmless – the toxin seems to require a human protein for it to be activated.

Yaws is an infection of the skin, bones and joints, found in tropical countries in Africa, Southeast Asia and the Pacific. It was previously believed to only be spread by direct skin contact with an infected individual, but new research led by a group at the German Primate Center, Germany, suggests that flies may carry the Treponema pallidum subsp. pertenue bacteria that cause the disease. The researchers found Treponema genes in around 20% of the wild flies they caught, and also noticed baboons inflicted with a very similar strain of T. pallidum. This means monkeys may be a non-human reservoir for the bacteria, and flies may be a vector to transmit the disease between them and humans. If this is the case, eradicating yaws may be more difficult than previously thought.

Many zoonotic diseases have jumped from animal host species to humans, but an international team shows Staphylococcus aureus may have gone the other way. The researchers compared strains of S. aureus taken from monkeys with strains from humans, both from The Gambia and nearby areas. Tests revealed that the strains looked to be related, and potentially resulted from human-to-monkey transmission as early as 2,700 years ago. More recently, some groups of monkeys even seemed to have acquired S. aureus from humans around seven years ago. The scientists warn that human encroachment on animal habitats may increase the risk of pathogens jumping host species, from both animal to human and human to animal.

Researchers at Kiel University, Germany, have found that nature itself has developed the best ways to inhibit biofilms – the sticky clumps of micro-organisms, sugars and nucleic acids that attach to surfaces, and help to protect bacteria from normal antibiotic treatments. To be able to coordinate themselves into a biofilm, bacterial cells communicate with each other using signal molecules, in a process called quorum sensing. Therefore, if the quorum sensing can be disrupted, the bacteria cannot form a biofilm. The research team discovered proteins, taken from sources like seawater and jellyfish, which can stop the signal molecules from functioning. In particular, a protein called QQ-2 was particularly good at disrupting quorum sensing in various types of biofilm. These findings may lead the way in developing improved medical treatments.

A new study by researchers at the Institute of Tropical Medicine Antwerp, Belgium, has mapped the path that Trypanosoma brucei parasites take after being transmitted to a mouse host through a tsetse fly bite. T. brucei are protozoa – a type of single-celled micro-organism – and cause the disease sleeping sickness. After tagging the trypanosomes with a fluorescent protein, the scientists were able to see how they spread within the mouse and noted that the parasites that were passed via a bite were better at infecting the host. In contrast, previous studies injected mouse hosts with T. brucei purified from infected blood, which had already changed to a less infectious form and did not always cause disease. 

For over 50 years, US farmers have faced an unknown tick-borne bacterium that was causing cattle to abort their calves. In the last few years, researchers at the University of California, Davis, USA, identified the microbe as one from the Myxococcus genus and are now inoculating cows against the disease. Both the carrier (the Pajaroello tick) and the bacterium (aptly named Pajaroellobacter abortibovis) were baffling. The micro-organism only replicated approximately once a day, making it hard to grow in a lab, whereas the arachnid did not behave like other ticks – instead of embedding itself into animal hosts, the Pajaroello tick inhabits decomposing plant matter and only occasionally makes the effort to feed on cows’ blood.

Mucormycosis is a little known, but often deadly, disease caused by a relatively obscure order of fungi – Mucorales. New research led by scientists at the University of Maryland School of Medicine, USA, has now revealed the molecular pathways that the fungus uses to infect people. As there are currently no vaccines or effective treatments, the researchers hope their findings can help to design new strategies to develop therapies and discovering prevention or early diagnosis methods.

A team at the University of Oregon, USA, has discovered that intestinal contractions directly affect gut microbe populations. The researchers observed two native zebrafish gut bacteria, Aeromonas veronii and Vibrio cholera, in real time and noticed that peristalsis – the natural contraction and relaxation of the gut – caused A. veronii numbers to drop dramatically, whereas V. cholera levels remained consistent. When the scientists investigated zebrafish that were unable to perform peristalsis, they found that A. veronii levels were unaffected. Humans with this mutation, also known as Hirschsprung’s disease, have bowel problems that can lead to infection. The insight into zebrafish gut microbiome interactions is significant, as they could lead to new therapies for the human disease.