Military health officials say troops are engaging in more high-risk sexual behavior, and part of the reason might be the popularity of smartphone dating apps.
Dating apps are becoming more popular, and while plenty of people use them to find love, others opt for one-night stands.
Apps like Tinder allow users who "match" with one another to skip the small talk and potentially hook up immediately. And if they're over it, they can block the person and never see or hear from them again.
This casual dating culture is creating headaches for many military health providers trying to help service members prevent and trace sexually transmitted infections.
"Social media has definitely been a part of the increase in the amount of STIs and the rise of STIs," said Maureen Sevilla, Chief of the Epidemiology and Disease Control Clinic at Womack Army Medical Center on Fort Bragg, N.C.
Nearly 350,000 troops were diagnosed with STIs between 2010 and 2018, according to a Medical Surveillance Monthly Report (MSMR) published in March by the Armed Forces Health Surveillance Branch, part of the Military Health System.
It also found rates for chlamydia, gonorrhea, and syphilis have been rising steadily over the last few years.
Chlamydia was by far the most common infection, affecting more than 200,000 service members during that time period and increasing more than 56% from 2013 to 2018.
There were about 33,000 incidences of gonorrhea, which increased by about 55% in men and 33% in women.
Syphilis affected a smaller amount of troops - a little under 4,700 who were mostly male. But the 2018 rate was 2.7 times higher than the rate in 2010.
According to the Department of Defense, one reason for these upticks is that "high-risk behaviors" like unsafe sex and having multiple partners have increased dramatically among service members.
The Department of Defence 2015 Health-Related Behavior Survey found high-risk behaviors among active-duty service members nearly doubled since the last reported survey in 2011. Results of a 2018 survey have yet to be released.
Those figures don't surprise 26 year-old Air Force veteran Elizabeth McGee of Tampa. She served at the Defense Language Institute at the Presidio of Monterey, Cal. from 2013 to 2016.
"A lot of people that I knew of at least that joined, they were either really, really young or they were from somewhere that didn't have much sex education," she said. "So they would get on these dating apps and be like, 'Oh, look at all these options,' and they would be out having intercourse without protection and having multiple partners."
The MSMR found the vast majority of troops with STIs were junior enlisted officers in their early-to-mid-20's with high school education or less.
McGee said some people at her base dated civilians but there was also a lot of hooking up within units, which could help infections spread. She laughed and shook her head as she recalled her own experiences using Tinder.
"I would match with people I had already seen before or that had already dated one of my friends, or I would date someone, and a week later they'd be dating someone else," she said. "So it was a small pond."
Higher STI rates in the military are also due to higher rates of screenings. People in the military have access to free testing and treatment on base, so it can be easier for them to address concerns about STIs compared with some civilians.
The military has also implemented programs that mandate screening for certain STIs.
For example, service members are screened for HIV at least every two years, and women under 26 are screened for chlamydia annually because they are more susceptible to infection and less likely to show symptoms. Health officials said that's part of the reason the MSMR found rates of certain STIs were "markedly" higher in women.
STIs are not just increasing in the armed forces, they're also an issue among civilians.
In June, officials with the World Health Organization noted concerns about people being complacent about protection, and sex becoming more accessible because of dating apps. This came after the UN health agency published a report that found every day globally there were more than one million new cases of treatable sexually transmitted infections.
Maureen Sevilla said there is heightened concern among military leaders because STIs affect readiness.
"They don't want a soldier getting HIV and becoming non-deployable or a soldier getting syphilis, and now we have to wait three months until we're sure that they're cured before they can be deployed," she said.
Infections like chlamydia and gonorrhea can typically be cured in a week or so with medication and would not limit someone's ability to deploy. But if left untreated, they can cause chronic health problems like pelvic inflammatory disease and joint issues. Gonorrhea is also becoming more resistant to certain treatments.
According to the MSMR, not all STIs increased. Genital herpes, or HSV, decreased slightly, while human papillomavirus, also known as HPV, decreased by more than 50%, which the report credits to more people receiving the HPV vaccine.
The study did not look at HIV, but health officials said rates have been relatively stable and could potentially decrease in the future now that the military is making pre-exposure prophylaxis or PrEP medication more widely available for troops.
Everyone in the military receives at least some STI prevention training. But Elizabeth McGee said she didn't feel the training she went through was effective.
"They (trainers) were just like, 'Oh this is what syphilis looks like, it's scary right?' Next slide, 'This is herpes, isn't it terrible?'" she said.
Fort Bragg is among the bases trying to make training better connect with young troops. Rather than just handing out brochures or showing PowerPoint presentations, health workers there are doing things like playing "STI Jeopardy" with troops to get them more involved in the learning process.
While providers say they can't stop service members from using dating apps, they can help people get tested and encourage them to swipe responsibly.
This story was produced by the American Homefront Project, a public media collaboration that reports on American military life and veterans. Funding comes from the Corporation for Public Broadcasting.