A tax increase on alcoholic beverages in Maryland led to a large decrease in cases of gonorrhea.

(Photo: Rich Renomeron/Flickr)

Everybody hates tax increases. But when specifically—and smartly—targeted, they can produce immediate and beneficial results.

That's what happened in Maryland, where the sales tax on alcohol was raised 50 percent four years ago. Apparently as a result, the rate of gonorrhea in that state subsequently declined 24 percent.

"These findings add to the mounting evidence that alcohol tax increases appear to be efficient structural interventions for STIs (sexually transmitted infections)," a research team led by Stephanie Staras, an assistant professor at the University of Florida College of Medicine writes in the American Journal of Preventive Medicine.

Effective July 1, 2011, Maryland raised the sales tax rate for alcoholic beverages from six percent to nine percent. Noting that the raise is "large compared with typical tax adjustments," Staras and her colleagues decided to investigate its impact on risky sexual behavior, and the diseases that are spread as a result.

In Maryland, the sales tax on alcohol was raised 50 percent four years ago. Apparently as a result, the rate of gonorrhea subsequently declined 24 percent.

Using data from the National Notifiable Disease Surveillance System, they examined rates of gonorrhea and chlamydia for 102 months before the increase, and 18 months afterwards. Besides a straight before-and-after comparison, the researchers also compared STI rates in a variety of other states to make sure the Maryland results weren't reflective of a national trend.

They weren't.

"Prior to the tax increase, gonorrhea rates in Maryland were higher than rates in (the other states and regions we looked at)," the researchers report. "Following the tax change, the gonorrhea rate appears to decrease in Maryland, and not in the three control groups."

Specifically, during the 18 months immediately following the increase, "an estimated 2,400 cases of gonorrhea were prevented (in Maryland), saving an estimated $519,600 in direct medical expenses," the researchers write.

In contrast, they found no significant change in the number of chlamydia cases. They cite two possible reasons for this.

First, "Gonorrhea cases are typically more geographically concentrated, and restricted to higher-risk populations," and thus more likely to be affected by this sort of intervention. Second, "Chlamydia-infected individuals are less likely to seek testing, owing to an increased probability of asymtomatic or mild infections."

The bottom line, Staras says, is clear: "If policymakers are looking for methods to protect young people from harmful STIs, they should consider raising alcohol taxes, which have decreased remarkably over the years due to inflation."

"Right now, the only population-level intervention for STIs recommended by the Centers for Disease Control and Prevention is condom distribution," she adds. "However, the effects we observed in this study are comparable to the effectiveness of condom distribution—and taxes generate revenue rather than spend it."

An excellent point. Given the clear public-health benefits, adding a few cents to the cost of cabernet seems a small price to pay.

Findings is a daily column by Pacific Standard staff writer Tom Jacobs, who scours the psychological-research journals to discover new insights into human behavior, ranging from the origins of our political beliefs to the cultivation of creativity.