The number of syphilis cases in Onondaga County has nearly doubled in the last year, up from 15 cases in 2012 to 29 cases in 2013.
Health experts are linking the spike to mobile apps for gay dating and hookups.
"It has been identified that a lot of these [syphilis] cases are because of recent activity amongst mobile apps such as Grindr, Adam4Adam and Jack'd," said K. Daniel Reed, an intervention specialist at ACR Health in Syracuse.
The Onondaga County Health Department reports that most of the cases are in men older than 30 who have sex with other men.
The department investigates every reported case of syphilis, and asks individuals specific questions about their sexual behavior.
"One of the questions is where they use these applications, these phone apps," said Onondaga County Health Commissioner Dr. Cynthia Morrow.
Onondaga County's spike in syphilis is three times as high as the state's 30% spike in syphilis cases, but the health department is unsure why.
Health experts point out that although the apps are linked to the STD spike, they are not to blame for an individial's behavior.
"When people are not protecting themselves, then it comes dangerous," said Reed. The act, the sexual act, becomes dangerous. Not the app."
Syphilis often manifests as a sore that develops at the site where the bacteria entered the individual's body. It is a potentially deadly disease, but can be cured if treated with a course of antibiotics such as penicillin.