Early warning signs
Sales data from pharmacies, grocers and other retailers is giving health officials in Washoe County a much-needed early warning about disease outbreaks.
Within a day or two of consumers’ visits to a pharmacy, health officials learn if consumers are buying more of the over-the-counter merchandise such as cold-relief pills that typically mark the start of an outbreak.
Most important, the sales data generated when product codes are scanned at cash registers often provides the first hint of an outbreak. It arrives at the county health department faster than other measures of disease outbreaks information on emergency room visits, for instance, or reports from physicians’ offices.
Fourteen retailers in Washoe County participate in the program known as the National Retail Data Monitor, says Lei Chen, a senior epidemiologist with the Washoe District Health Department.
Retail sales data is collected from those 14 stores and transmitted to the University of Pittsburgh. The university, in turn, delivers localized data for free to the Washoe District Health Department and other participating agencies around the country.
Any personal information about the buyers is stripped from the data by the participating retailers, and the health department gets information on the sales of 18 types of products everything from anti-diarrhea medicines to pediatric thermometers.
Chen says health officials in Washoe County keep a particularly close eye on eight products on the list of 18 cold relief liquids and tablets for adults and children, cough syrups and anti-diarrhea products.
Health officials get updated sales information each day. The data is massaged to remove the effects of other factors that might boost sales a big price promotion on cough syrup, for instance.
The data isn’t an infallible indicator of disease outbreaks, says Randall Todd, director of the division of epidemiology and public health preparedness in Washoe County.
But, he says, it provides a valuable set of hints to health officials.
The retail data is particularly useful, he says, because consumers often try to treat themselves with over-the-counter medications before they visit a physician.
That means the retail data gives health officials an additional few days alert about outbreaks that are developing. And time can be important in establishing preventive strategies.
Still, Todd says, “You have to be careful. When do you cry wolf and launch into larger community involvement?”
The drive to use retail data to track outbreaks of illness has been further spurred, Todd says, by the desire of federal officials to develop better tools to combat bio-terrorism.
In case of bio-terror attacks, just like outbreaks of the flu or other traditional illnesses, health officials hope to get an early warning from sales of over-the-counter medicines, then get more information later from emergency room visits, ambulance calls and physicians reports.
Nationally, health departments receive basic data about the reasons that consumers show up at emergency rooms. In Washoe County, health officials also get data about the reason for ambulance calls again, personal data is stripped out and the health department surveys a sample of physicians’ officers once a week to get information about flu or other outbreaks.
Chen says the 14 stores in Washoe County that provide data represent about 20 percent of those eligible to participate in the program. Nationwide, about 50 percent of eligible retailers participate.
Because of the secrecy involved, not even Washoe County health officials know the identities of the local stores that participate.