Detection of Ampicillin-Resistant E. coli Using Novel Nanoprobe-Combined Fluorescence In Situ Hybridization

Field grand challenge with emerging superbugs and the novel coronavirus (SARS-CoV-2) on plastics and in water

This opinion paper reports field grand challenges associated with plastic and water contaminated with the novel coronavirus (severe acute respiratory syndrome coronavirus 2, SARS-CoV-2) and superbugs, given the emergency of public health and environmental protection from the presence of lethal viruses and bacteria. Two primary focuses of detection and treatment methods for superbugs and the novel coronavirus (SARS-CoV-2) are investigated, and the future outlook is provided based on grand challenges identified in the water field. Applying conventional treatment technologies to treat superbugs or the novel coronavirus (SARS-CoV-2) has brought negative results, including ineffective treatment, formation of toxic byproducts, and limitation of long-term performance. Existing detection methods are not feasible to apply in terms of sensitivity, difficulty of applications in field samples, speed, and accuracy at the time of sample collection. Few studies are found on superbugs or adsorption of the novel coronavirus (SARS-CoV-2) on plastic, as well as effects of superbugs or the novel coronavirus (SARS-CoV-2) on treatment of plastic waste and wastewater. With the need for and directions of further research and challenges discussed in this paper, we believe that this opinion paper offers information useful to a wide audience, including scientists, policy makers, consultants, public health workers, and field engineers in the water sector.

Bacterial Causes for Mortality Syndrome in Some Marine Fish Farms with Treatment Trials

BACKGROUND AND OBJECTIVE

Bacterial fish diseases constitute a major problem in aquaculture, it was found in the environment and under stressors cause severe economic losses to fish. This work aimed to investigate the bacterial causes and suitable treatments of mass mortality in some cultured marine fish farms in Damietta governorate.

MATERIALS AND METHODS

The study was performed on 5 farms suffered from mass mortality. Total of 100 diseased fish (10 sea bass and 10 sea bream/farm) and 20 water samples were randomly collected from these farms. Bacteriological examinations were carried out followed by in vitro sensitivity tests. Treatment trial was performed using the most effective antibacterial agent on isolated bacteria.

RESULTS

From fish and water samples Pseudomonas spp., Aeromonas spp. and Vibrio spp. were isolated with the rat of (16, 10%), (22, 10%) and (28, 10%) respectively. These results were confirmed biochemically. Some virulence genes of isolated bacteria were detected using PCR; meanwhile, enrofloxacin reduced significantly the mortality rates in examined farms.

CONCLUSION

It could be concluded that, Pseudomonas spp., Aeromonas spp. and Vibrio spp. are the main bacterial species causing mass mortality in marine fish farms. These bacteria were highly sensitive to enrofloxacin in vitro and in vivo.

Treatment Trial of Nile Tilapia (Oreochromis niloticus) Experimentally Infected with Vibrio alginolyticus Isolated from Sea bass (Dicentrarchus labrax)

BACKGROUND AND OBJECTIVE

In Egypt, Nile tilapia represents the main cultured type due to its economical price, palatability and easy culturing. This study was aimed to elucidate the pathogenicity of V. alginolyticus isolated from diseased sea bass and experimentally infected healthy Nile tilapia fish.

MATERIALS AND METHODS

Healthy Nile tilapia fish were injected I/P with V. alginolyticus isolated from diseased sea bass. Symptoms and mortality rates of infected Nile tilapia fish were recorded during the experimental period. Re-isolation of V. alginolyticus was done from infected tilapia fish by bacteriological methods. For confirmation the pathogenicity of Vibrio isolated either from marine fish or tilapia fish, PCR test was done using tdh and bla gens. Liver and kidney function tests with histopathological examinations of some organs were performed. Treatment trial was done according to the antibiotic sensitivity test.

RESULTS

The isolated Vibrio is highly pathogenic to Nile tilapia fish causing deterioration in all parameters which finished by severe mortalities. Treatment with florfenicol, enrofloxacin, or oxytetracycline reduced the mortality rate and improved liver and kidney function parameters of infected Nile tilapia fish.

CONCLUSION

V. alginolyticus can infect both marine and fresh water fish inducing a high mortality rate. Treatment of infected fish with florfenicol, enrofloxacin, or oxytetracycline reduces the mortality rate.