Survival of Listeria monocytogenes in uncooked Italian dry sausage (salami).

This study was undertaken to supplement existing information on the survival of Listeria monocytogenes in Italian salami. The fact that Italian salami is frequently consumed by a large number of people poses some serious health implications. Some raw materials have been found to be microbiologically contaminated, for their production occurs without any thermic treatment, and these are in circulation throughout Italy all year round. We selected the product for its microbiological, technological, and commercial characteristics. We analyzed 1,020 samples taken during the autumn and winter 2002 and spring and summer 2003 periods and immediately before selling. The samples were collected from 17 plants with an annual production of between 1 and 2,000 metric tons and with a distribution of products in over 80% of Italy in geographic terms. To detect and enumerate L. monocytogenes, we followed International Organization for Standardization (ISO) 11290 part 1 and 2: 1996 (modified using chromogenic medium Agar Listeria according to Ottarviani and Agosti [ALOA]). L. monocytogenes was found in 22.7% of samples, but the contamination level was less than 10 CFU/g. Contamination prevalence ranged from 1.6 to 58.3% and was lower than 10% in 5 of the 17 plants checked. The most frequently isolated serotypes were 1/2c, 1/2a, 1/2b, and 4b. Additional studies are necessary to establish if the exposure to a small number of L. monocytogenes cells through the consumption of salami represents a significant health risk and, in light of the future introduction of the SANCO/4198/2001 revision 21 "Commission Regulation on Microbiological Criteria for Foodstuffs," is a necessary investigation

Closed-circuit system for the depuration of mussels experimentally contaminated with hepatitis A virus.

In Italy, the consumption of raw or slightly cooked mussels represents the most important risk factor for the transmission of hepatitis A virus (HAV). Although there exist effective methods for the bacterial depuration of contaminated mussels, these methods are poorly effective on enteric viruses. The objective of the present study was to evaluate the effectiveness of a closed-circuit depuration system that uses both ozone and UV light for disinfecting water and that allows salinity and temperature, important parameters for the metabolism of mussels (Mytilus galloprovincialis), to be maintained at constant levels. The results showed that this depuration method decreased the viral load (from 1.72 log 50% tissue culture infective dose [TClD 50 ] ml -1 to <1 log TCID 50 ml -1 within 24 h and from 3.82 log TCID 50 ml -1 to <1 log TCID 50 ml -1 within 48 h). However, in both cases, after 120 h of depuration, a residual amount of virus capable of replicating in cells was detected. These results show that depuration, even if performed with advanced systems, may not guarantee the absence of virus

Management of Animal Botulism Outbreaks: From Clinical Suspicion to Practical Countermeasures to Prevent or Minimize Outbreaks

Botulism is a severe neuroparalytic disease that affects humans, all warm-blooded animals, and some fishes. The disease is caused by exposure to toxins produced by Clostridium botulinum and other botulinum toxin–producing clostridia. Botulism in animals represents a severe environmental and economic concern because of its high mortality rate. Moreover, meat or other products from affected animals entering the food chain may result in a public health problem. To this end, early diagnosis is crucial to define and apply appropriate veterinary public health measures. Clinical diagnosis is based on clinical findings eliminating other causes of neuromuscular disorders and on the absence of internal lesions observed during postmortem examination. Since clinical signs alone are often insufficient to make a definitive diagnosis, laboratory confirmation is required. Botulinum antitoxin administration and supportive therapies are used to treat sick animals. Once the diagnosis has been made, euthanasia is frequently advisable. Vaccine administration is subject to health authorities' permission, and it is restricted to a small number of animal species. Several measures can be adopted to prevent or minimize outbreaks. In this article we outline all phases of management of animal botulism outbreaks occurring in wet wild birds, poultry, cattle, horses, and fur farm animals

Application of a Loop-Mediated Isothermal Amplification (LAMP) Assay for the Detection of <i>Listeria monocytogenes</i> in Cooked Ham

Changing eating habits and rising demand of food have increased the incidence of foodborne diseases, particularly in industrialized countries. In this context, contaminated ready-to-eat food (RTE) may be a vehicle for the transmission of Listeria monocytogenes (L. monocytogenes), a foodborne pathogen responsible of listeriosis, a severe infectious disease involving humans and animals. It would be useful to have rapid detection methods to screen the presence of L. monocytogenes in food. In this study, a colorimetric Loop-mediated isothermal amplification (LAMP) assay was applied to the detection of L. monocytogenes in 37 experimentally contaminated RTE meat samples. The LAMP primers consisted of a set of six primers targeting eight regions on the hlyA gene; the assay was carried out in 30 min at 65 °C in a water bath. Amplification products were visualized by color change assessment. The results of colorimetric LAMP assays based on the hly gene obtained in this study were compared to microbiological cultural methods, real-time PCR and real-time LAMP PCR, which show 100% specificity and sensitivity. These data suggest that colorimetric LAMP assays can be used as a screen to detect L. monocytogenes in ready-to-eat meat food