Evaluation of sample recovery efficiency for bacteriophage P22 on fomites.

Fomites are known to play a role in the transmission of pathogens. Quantitative analysis of the parameters that affect sample recovery efficiency (SRE) at the limit of detection of viruses on fomites will aid in improving quantitative microbial risk assessment (QMRA) and infection control. The variability in SRE as a function of fomite type, fomite surface area, sampling time, application media, relative humidity (rH), and wetting agent was evaluated.

Implications of limits of detection of various methods for Bacillus anthracis in computing risks to human health.

Used for decades for biological warfare, Bacillus anthracis (category A agent) has proven to be highly stable and lethal. Quantitative risk assessment modeling requires descriptive statistics of the limit of detection to assist in defining the exposure. Furthermore, the sensitivities of various detection methods in environmental matrices are vital information for first responders.

In situ-synthesized virulence and marker gene biochip for detection of bacterial pathogens in water.

Pathogen detection tools with high reliability are needed for various applications, including food and water safety and clinical diagnostics. In this study, we designed and validated an in situ-synthesized biochip for detection of 12 microbial pathogens, including a suite of pathogens relevant to water safety. To enhance the reliability of presence/absence calls, probes were designed for multiple virulence and marker genes (VMGs) of each pathogen, and each VMG was targeted by an average of 17 probes.

Influence of dangling ends and surface-proximal tails of targets on probe-target duplex formation in 16S rRNA gene-based diagnostic arrays.

Dangling ends and surface-proximal tails of gene targets influence probe-target duplex formation and affect the signal intensity of probes on diagnostic microarrays. This phenomenon was evaluated using an oligonucleotide microarray containing 18-mer probes corresponding to the 16S rRNA genes of 10 waterborne pathogens and a number of synthetic and PCR-amplified gene targets. Signal intensities for Klenow/random primer-labeled 16S rRNA gene targets were dissimilar from those for 45-mer synthetic targets for nearly 73% of the probes tested.