Motile Aeromonas Septicemia (MAS)

- Control of disease

➡️  Preventive measures

▪️  A. hydrophia exhibits biochemical and serological heterogeneity, therefore, there are no commercial obtainable vaccines for MAS (Pridgeon and Klesius, 2012). However, researchers have developed vaccines from locally isolated strains such as live attenuated, formalin and autoclaved inactivated vaccine (Youssef et al., 2023), lipopolysaccharide vaccine (Dehghani et al., 2012) that showing promise protection against MAS.

▪️  Preventive measures against MAS involve improving aquaculture management to reduce stress, tissue injuries, and prevention of parasites and other infectious agents. Effective treatment should start once a fish infection with A. hydrophila is confirmed (Swann and White 1991). Applications of bacteriophages against MAS have been reported in striped catfish (Le et al., 2018) and tilapia (El-Araby et al., 2016).

▪️  Many herbal immunostimulants, probiotics and prebiotics have been improved fish immune system and resistance against aeromonas infection (Abd El-latif et al., 2021)

➡️  Treatment

▪️ Appropriate application of antibiotics is important to treat pathogenic bacteria and minimize the development of antibiotic resistance in aquaculture. Therefore, antibiotics should only be used when the fish still feeding well, and the medicated diets must be regularly administered at the therapeutic dose for the duration of the prescribed treatment period.

▪️  A. hydrophila strains have been developed Multiple antibiotic resistance (MAR) worldwide (Vivekanandhan et al., 2002).

▪️  There are three feed-based treatments available against MAS, Terramycin® (oxytetracycline), Romet 30® (sulfadimethoxine plus ormetoprim), and Aquaflor® (florfenicol). The U.S. Food and Drug Administration has only approved Terramycin® for treatment against Aeromonas in salmonids and catfish.

➡️ Zoonotic importance

▪️ A. hydrophila is a food-borne pathogen, has zoonotic importance and can be transmitted to humans via consumption of contaminated water and raw or uncooked infected aquatic products (Yousr et al., 2007)

▪️  Infection with A. hydrophila can result in gastrointestinal infection (watery diarrhea to dysenteric or bloody diarrhea) or non-gastrointestinal complications (hemolytic syndrome and kidney disease, bacteremia and septicemia, cellulitis, meningitis, ocular infections, pneumonia, urinary tract infection in neonates, osteomyelitis, peritonitis and acute cholecystitis (Borger et al., 2006).