Sponges and sprays are not the only tools in the fight against infectious disease outbreaks — for environmental health researchers like Dr. Mark Weir, math equations can be just as powerful. Dr. Weir is an assistant professor of epidemiology and biostatistics at Temple’s College of Public Health whose research team just published a paper in Environmental Science and Technology. Their focus: building a mathematical model that identifies objects that might harbor microbes even after being disinfected. It is a tool that could change the way healthcare facilities prevent infectious disease outbreaks.
Dr. Weir and his team based their research on a risk analysis method called Quantitative Microbial Risk Assessment. QMRA is used to predict and prevent outbreaks by assessing the circumstances that make microbes more likely to make people sick. But Dr. Weir says the model doesn’t account for the fact that surfaces like wood, plastic, and metal can often retain microbes even after being tested and disinfected — in other words, it is not an accurate tool for analyzing risk in indoor environments. That is a major potential problem in places like hospitals, eldercare and daycare facilities, where people are especially susceptible to infection.
To fill this gap, Dr. Weir and his team developed a new QMRA model that better estimates the number of microbes remaining on a surface after it’s been disinfected. “It’s a big step forward,” says Weir. “The real value is that we can now target specific surfaces for increased disinfection.” For example, he explains, “anything that’s made of aluminum or stainless steel should be disinfected more, because those surfaces retain more pathogens.” Dr. Weir says that healthcare facilities will be able to use the model to better assess whether they’ve disinfected patient rooms and other areas enough — saving time, resources, and ultimately, lives.