What does pumping oil have to do with a rise in sexually transmitted disease? More than you might think, new research shows.

Since about 2007, some areas of the U.S. have seen a massive increase in hydraulic fracturing, also known as fracking. The process involves injecting a high-pressure mixture of water, sand and chemicals into deep rock formations. Cracks in the rock are forced open and oil and natural gas are extracted.

Above ground, there’s also been a spinoff social effect of fracking. It typically brings an employment boom and those jobs are often filled by young men with no connection to the community. Researchers from Old Dominion and Valdosta State universities analyzed data from 176 counties in four states experiencing a fracking boom — Ohio, Pennsylvania, West Virginia and New York. They compared the number of reported cases of gonorrhea in those areas with rates in counties where there was no fracking.

Their conclusion: The growth in gonorrhea cases coincided with the start of the fracking boom. In counties with heavy fracking, the number of gonorrhea cases climbed steadily between 2009 and 2013. There was no growth in counties without fracking.

After controlling for other factors, researchers said fracking is associated with a 20 percent increase in gonorrhea. They said the findings could shed light on how the oil boom is leading to higher rates of sexually transmitted diseases. Ultimately, that could help public health agencies organize and launch prevention programs in areas where fracking is occurring or being considered.

When a fracking boom hits, there are many effects on a community — and it’s not just about economic activity.