Abstract
Existing microbial risk assessment models rarely incorporate detailed descriptions of human interaction with fomites. We develop a stochastic-mechanistic model of exposure to rotavirus from nondietary ingestion iterated by simulated intermittent fomes-mouth, hand-mouth, and hand-fomes contacts typical of a child under six years of age. This exposure is subsequently translated to risk using a simple static dose-response relationship. Through laboratory experiments, we quantified the mean rate of inactivation for MS2 phage on glass (0.0052/hr) and mean transfer between fingertips and glass (36%). Simulations using these parameters demonstrated that a child's ingested dose from a rotavirus-contaminated ball ranges from 2 to 1,000 virus over a period of one hour, with a median value of 42 virus. These results were heavily influenced by selected values of model parameters, most notably the concentration of rotavirus on fomes, frequency of fomes-mouth contacts, frequency of hand-mouth contacts, and virus transferred from fomes to mouth. The model demonstrated that mouthing of fomes is the primary exposure route, with hand mouthing contributions accounting for less than one-fifth of the child's dose over the first 10 minutes of interaction.
Original language | English (US) |
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Pages (from-to) | 617-632 |
Number of pages | 16 |
Journal | Risk Analysis |
Volume | 29 |
Issue number | 5 |
DOIs | |
State | Published - May 2009 |
Externally published | Yes |
Keywords
- Exposure assessment
- Fomites
- Micro-level activity data
- Microbial risk assessment
- Rotavirus
- Stochastic modeling
ASJC Scopus subject areas
- Safety, Risk, Reliability and Quality
- Physiology (medical)