Prevalence of hepatitis A virus in bivalve molluscs sold in Granada (Spain) fish markets.

Viruses are the leading cause of foodborne illness associated with the consumption of raw or slightly cooked contaminated shellfish. The aim of this study was to evaluate the prevalence of hepatitis A virus in molluscs. Standard and real-time reverse transcription-polymerase chain reaction procedures were used to monitor bivalve molluscs from the Granada fish markets (southern Spain) for this human enteric virus. Between February 2009 and October 2010, we collected a total of 329 samples of different types of bivalve molluscs (mussels, smooth clams, striped venus, and grooved clams). The results showed the presence of hepatitis A virus in 8.5% of the 329 samples analyzed. We can therefore confirm that conventional fecal indicators are unreliable for demonstrating the presence or absence of viruses. The presence of hepatitis A virus in molluscs destined for human consumption is a potential health risk in southern Spain.

Enterococcus faecalis biofilms eradication by root canal irrigants.

The aim of this study was to evaluate the minimal biofilm eradication concentration (MBEC) of sodium hypochlorite (NaOCl), chlorhexidine (CHX), EDTA, and citric and phosphoric acids after 1, 5, and 10 minutes of exposure to biofilms of Enterococcus faecalis. The biofilms grew in the MBEC high-throughput device for 24 hours at 37 degrees C and were exposed to 10 serial two-fold dilutions of each irrigating solution. The viable cell counts were log(10) transformed, and a concentration of an irrigant was considered to eradicate the biofilms when it produced a reduction of > or = 5 logarithmic units. NaOCl was the most effective agent, capable of eradicating the biofilms after 1 minute at a concentration of 0.00625%. CHX eradicated biofilm after 5 minutes at 2%. EDTA and citric and phosphoric acid solutions were not effective against the biofilms at any concentration or time tested.

Bactericidal activity of phosphoric acid, citric acid, and EDTA solutions against Enterococcus faecalis.

OBJECTIVES: The objectives of this study were to evaluate the minimal bactericidal concentration (MBC) for Enterococcus faecalis of phosphoric acid, citric acid, and ethylenediaminetetraacetic acid (EDTA) solutions, and to determine the contact time required for 2.5% and 5% phosphoric acid, 10% and 25% citric acid, and 17% EDTA to exert bactericidal activity. STUDY DESIGN: Bactericidal activity was tested by means of the dilution neutralization method in accordance with BS-EN-1040:2005 norm, using contact times of 0.5 to 60 minutes. RESULTS: The MBCs of citric and phosphoric acid were 20% and 2.5%, respectively. EDTA solution lacks bactericidal activity, even after 60 minutes of contact. The 2.5% and 5% phosphoric acid solutions required 5- and 3-minute contact times, and the 10% and 25% citric acid solutions required 10- and 3-minute contact times, respectively. CONCLUSIONS: Phosphoric acid revealed bactericidal activity against E. faecalis and required less time than citric acid to exert its activity.