Comparative analysis of viral pathogens and potential indicators in shellfish.

Area of Science:

• Food safety and public health
• Environmental microbiology
• Virology

Background:

• Shellfish consumption is linked to infectious disease outbreaks.
• Current health measures are insufficient to guarantee the absence of viral pathogens in shellfish.
• Understanding viral contamination in shellfish is crucial for public health.

Purpose of the Study:

• To analyze the presence of pathogenic viruses and potential indicators in shellfish from areas with varying fecal contamination levels.
• To evaluate human adenovirus, enterovirus, and hepatitis A virus (HAV) prevalence.
• To assess the suitability of bacteria and bacteriophages as indicators of viral contamination.

Main Methods:

• Sixty shellfish samples were collected from three sites with different contamination levels.
• Analysis included Escherichia coli, total coliforms, Clostridium perfringens, somatic coliphages, F-specific RNA phages, Bacteroides fragilis phages, human adenovirus, enterovirus, and HAV.
• Viruses were detected using elution in a glycine buffer (pH 10) and molecular methods.

Main Results:

• Pathogenic viruses were detected in a significant percentage of samples: 47% for human adenoviruses, 19% for enteroviruses, and 24% for HAV.
• All enterovirus and HAV positive samples were also positive for human adenovirus, suggesting its utility as an indicator.
• Bacteriophage detection increased with virus presence, and higher water temperatures correlated with decreased virus detection probability.

Conclusions:

• Human adenovirus may serve as a valuable molecular indicator for viral contamination in shellfish.
• Phages infecting Bacteroides fragilis RYC2056 show promise as indicators for the presence of viruses in shellfish.
• Further research is needed to establish robust viral indicators for shellfish safety control.