Microbial study of household hygiene conditions and associated Listeria monocytogenes infection risks for Peruvian women.

Objectives: To develop an exposure and risk assessment model to estimate listeriosis infection risks for Peruvian women.

Methods: A simulation model was developed utilising Listeria monocytogenes concentrations on kitchen and latrine surfaces in Peruvian homes, hand trace data from Peruvian women and behavioural data from literature. Scenarios involving varying proportions of uncontaminated, or 'clean', surfaces and non-porous surfaces were simulated.

Isolation, genotyping and antimicrobial resistance of Shiga toxin-producing Escherichia coli.

Shiga toxin-producing Escherichia coli (STEC) is an enteric pathogen linked to outbreaks of human gastroenteritis with diverse clinical spectra. In this review, we have examined the currently methodologies and molecular characterization techniques for assessing the phenotypic, genotypic and functional characteristics of STEC O157 and non-O157. In particular, traditional culture and isolation methods, including selective enrichment and differential plating, have enabled the effective recovery of STEC.

Antimicrobial resistance profiles of Shiga toxin-producing Escherichia coli O157 and Non-O157 recovered from domestic farm animals in rural communities in Northwestern Mexico.

Background: Antimicrobial resistance in Shiga toxin-producing Escherichia coli (STEC) O157 and non-O157 is a matter of increasing concern. The aim of the present study was to investigate the antimicrobial resistance profiles of STEC O157 and non-O157 recovered from feces of domestic farm animals in the agricultural Culiacan Valley in Northwestern Mexico.

Findings: All of the examined STEC strains showed susceptibility to five antimicrobials, ceftazidime, ceftriaxone, ciprofloxacin, nalidixic acid, and trimethoprim-sulfamethoxazole.

Prevalence and characterization of Listeria monocytogenes, Salmonella and Shiga toxin-producing Escherichia coli isolated from small Mexican retail markets of queso fresco.

Queso fresco (QF) is a handmade cheese consumed and produced in Latin America. In Mexico, QF production is associated with a microbiological risk. The aim of the study was to determine the incidence and characterization of Listeria monocytogenes, Salmonella spp.

Effectiveness of poliovirus concentration and recovery from treated wastewater by two electropositive filter methods.

Enteric viruses are often present in low numbers in various water matrices. Virus sampling therefore involves multiple concentration steps to condense large samples down to small volumes for detection by cell culture or molecular assays. The NanoCeram® Virus Sampler has been demonstrated to be effective for the recovery of viruses from tap water, surface waters, and seawater.

Sanitizing alternatives for Escherichia coli and Salmonella typhimurium on bell peppers at household kitchens.

Fresh fruits and vegetables are known to play an important role as carriers of disease-causing organisms in household kitchens. The aims of this study were to assess and compare the effectiveness of sodium hypochlorite, organic acid-based and silver-based products to reduce Escherichia coli and Salmonella typhimurium inoculated on individual bell pepper pieces. Inoculated bell pepper pieces (n = 5) were submerged in sodium hypochlorite, organic acid-based and silver-based product solutions, at the concentration specified in the product label for sanitization of fruits and vegetables.

New method using a positively charged microporous filter and ultrafiltration for concentration of viruses from tap water.

The methods used to concentrate enteric viruses from water have remained largely unchanged for nearly 30 years, with the most common technique being the use of 1MDS Virozorb filters followed by organic flocculation for secondary concentration. Recently, a few studies have investigated alternatives; however, many of these methods are impractical for use in the field or share some of the limitations of this traditional method. In the present study, the NanoCeram virus sampler, an electropositive pleated microporous filter composed of microglass filaments coated with nanoalumina fibers, was evaluated.

Relationships between the occurrence of Giardia and Cryptosporidium and physicochemical properties of marine waters of the Pacific Coast of Mexico.

Untreated sewage has adversely affected the quality of marine recreational waters worldwide. Exposure to marine recreational water with poor microbial quality may pose a threat to bathers. The objectives of this study were to assess the effect of physicochemical parameters on Cryptosporidium and Giardia presence in marine recreational water of Sinaloa, Mexico, by Logistic Regression Analyses.

Risk assessment of cryptosporidium and giardia in water irrigating fresh produce in Mexico.

A rise in foodborne outbreaks in the United States associated with fresh produce has resulted in increased concerns with the importation of fruits and vegetables. Mexico is a major exporter of produce to the United States, particularly tomatoes and bell peppers. A quantitative microbial risk assessment (QMRA) was conducted to evaluate the public health impact of protozoan-laden water irrigating produce in Culiacan, Sinaloa, Mexico.