Sharks and rays as a source of dangerous bacteria: what do data show

Sharks and rays – not the first thing that often comes to mind when it comes to products on a menu. However, they are often consumed in many coastal communities like Rio de Janeiro, Brazil’s coast! But although these two species are a major dietary element, they are a significant lack of research on bacterial risks associated with these marine species (especially given the possible health threats presented by antibiotic -resistant bacteria). A recent study tried to fill this gap by performing a bacteriological rating on sharks and the rays descended to one of the most important ports of the region’s fishing. The results revealed a disturbing presence of various pathogenic bacteria, some of which are known to pose significant public health risks.

Led by Dr. Maíra Hands Cardoso of Fundação Instituto de Pesca will Estado will rio de Janeiro, the team began to isolate bacteria from the cloacal pushes of some elassmobranchs taken from the sample. The bacteria were cultivated, and thus began the identification process, which included biochemical analysis, antimicrobial sensitivity testing and polymerase chain reaction analysis (PCR). Looks like many steps – and it’s! – But this allowed researchers to determine not only the types of bacteria present, but also their possible resistance to antibiotics, a critical factor in the spread of infection. Were identified a range of strains, including Vibrio, AeromonasAND Enterobacterales. Known to play a role in human infections, these bacteria are important in a health context, where the health of humans, animals and the environment is considered interconnected.

Among the most widespread bacteria found were Morganella Morganii AND Citrobacter Freundiiboth are EnterobacteralesA family of bacteria that includes various pathogens that are known to cause gastrointestinal disease. Vibrio Harveyi AND Vibrio fluvialis were the predominant species of Vibrio found while while Aeromonas allosacharophila AND Aeromonas Veronii BV. Veroni were more frequent Aeromonas species; These bacteria are often associated with water diseases and can lead to severe infections in humans, especially those with compromised immune systems. The fact that these species were found in sharks and rays is disturbing, especially as they can be transmitted to people through direct contact or bare food consumption.

What raised the further alarms in the study were the signs of antimicrobial resistance found in some of the bacteria. For example, 10% of Vibrio Isolated strains were resistant to trimethoprim-sulfamethoxazole, an antibiotic that is commonly used to treat infections. Moreover, 40% of strains showed intermediate resistance to cefoxit, a drug used to treat bacterial infections in humans. Worrying, especially because they suggest that some of the bacteria present in sharks and rays may be more difficult to treat, especially in the case of infection. Similarly, Salmonella Enterica Stranges isolated from elarasmobranchs showed intermediate resistance to ciprofloxacin, nalidixic acid and streptomycin – all of these are important antibiotics used to treat various bacterial infections.

Cardoso’s and her team also performs a serological rating for Salmonella Enterica Subsp. greatera, especially looking for Typhimurium serovarwhich is known to be zoonotic (this means it can be transmitted from animals to humans, potentially through the consumption of contaminated sea food). The discovery of this serrovar is important because it highlights the possible role of sharks and rays in the epidemiological chain of salmonelosis – a type of food -born disease that can cause serious gastrointestinal issues in humans. These findings, the authors argue, emphasize the need for more comprehensive studies and supervision of bacteria found in elassmobranchs, especially in areas where their consumption is high.

It is interesting while the study identified various potentially harmful bacteria, he did not find pathogenic genes in Escherichia coli The examined strains, suggesting that these particular strains may not be a direct threat regarding the cause of the disease. However, the overall presence of bacteria with the potential of pathogenicity – especially those that exhibit antibiotic resistance – is great worrying. The discovery of antimicrobes resistant bacteria in these predators is a reminder that our planet is currently facing a growing problem: resistance to antibiotics. A problem that, if left untreated, can complicate the treatment of infections and lead to more serious public health results.

With high consumption rates of elarasmobranchs in Brazil, especially in coastal communities, the potential for zoonotic transmission of bacteria cannot be ignored. Public health authorities and researchers have been warned about the detection of pathogenic and antibiotic -resistant bacteria in this sunshine, but warning should be taken into account wherever these species are consumed.