Cases of some sexually transmitted diseases, including chlamydia, gonorrhea and syphilis, are rising in the U.S. armed forces, a trend that mirrors the general population but alarms military health officials who treat affected troops.

According to a report released earlier this year by the Armed Forces Health Surveillance Branch, incidence rates of chlamydia in service men and women more than doubled from 2013 to 2018, gonorrhea infection rates also doubled for men and rose by 33 percent for women, and diagnoses of syphilis were nearly three times the number just 10 years ago.

In a press release Wednesday, Defense Department officials said the increases can mean negative consequences for military readiness.

"From a military standpoint, sexually transmitted infections can have a significant impact on individual readiness, which in turn impacts unit readiness, which then leads to a decrease in force health protection," said Maj. Dianne Frankel, an Air Force internal medicine physician, in the release.

Nearly 350,000 troops were diagnosed with a sexually transmitted illness between 2010 and 2018. According to the report, that included 212,405 cases of chlamydia, 32,987 cases of gonorrhea, 4,674 cases of syphilis, 28,295 cases of genital herpes and 71,138 cases of HPV

Women were "markedly" more affected than for men for all infections except syphilis, and younger troops, ages 24 and under, were affected at rates higher than any other age group for most of the diseases.

Related: Military Rate of Sexually Transmitted Diseases Defies Treatment Efforts

Across the services, rates for chlamydia, gonorrhea, and genital herpes simplex virus were highest in the Army. The Navy had the highest overall rate of syphilis, while the Air Force had the highest rate of genital human papillomavirus (HPV) cases.

In some good news, the overall incidence rates for HPV and herpes simplex declined over the 8-year observation period for men and women. Rates went down by more than 51 percent for HPV and 19 percent for herpes, according to the Medical Surveillance Monthly Report (MSMR) for the month of March.

Frankel said in addition to affecting readiness, sexually transmitted diseases "place a significant economic strain on the U.S. and military health care systems."

In 2012 alone, according to the release, the Navy paid $5.4 million in STD-associated health care treatment costs.

Undetected STDs can cause serious health consequences. Chlamydia, which frequently is asymptomatic, can cause infertility in women. HPV is linked to several types of cancer. And while three of the types of STDs studies are curable with antibiotics, the medical community continues to be concerned about the rise of infectious diseases resistant to medications.

The Centers for Disease Control and Prevention, for example, has launched an aggressive campaign to combat treatment-resistant gonorrhea. Since 2006, doctors had five medications they could choose from to treat the disease; now only one is effective.

Today, roughly 30 percent of new gonorrhea infections have some type of resistance.

Defense Department officials say cases may be on the rise because troops are increasingly engaging in high-risk sexual behaviors, having sex without a condom or having more than one sexual partner.

Social media and dating apps may also play a role, said Norma Jean Suarez, a nurse practitioner in preventive medicine at Brooke Army Medical Center, San Antonio, Texas.

According to Suarez, access to random or anonymous sexual encounters can contribute to exposure. Having anonymous sex is on the CDC's list of behaviors that increase risk for contracting a sexually transmitted disease.

The 2015 DoD Health Related Behaviors Survey found that nearly 20 percent of respondents said they had more than one sex partner in the previous year and 37 percent reported having sex without a condom.

The report provided a look at diagnosis rates for sexually transmitted diseases based on diagnosis, reports and lab results. The report did not include human immunodeficiency virus, or HIV. According to a September 2017 MSMR, there were an average of 350 new HIV infections per year among U.S. service members between 2010 and 2016, a rate of roughly 25 diagnoses per 100,000 persons.

Personnel can protect themselves by abstaining, unless they are in a long-term, mutually monogamous relationship or using condoms, according to Col. Amy Costello, chief of preventive medicine at the Air Force Medical Support Agency.

They also protect themselves from HPV -- a sexually transmitted infection that can cause six types of cancer -- by making sure they have completed their series of vaccines for the virus.

"Sexually transmitted infections are preventable," Frankel said in the release. "It's important for everyone to know how to protect themselves and their partners."

-- Patricia Kime can be reached at Patricia.Kime@Military.com. Follow her on Twitter at @patriciakime.