CDC officials say sexually transmitted diseases are at an all-time high for a number of reasons, but there are easy ways to avoid being infected.

Despite all of the available information on prevention, it appears sexually transmitted diseases (STDs) are still alive and well.

The annual report from the Centers for Disease Control and Prevention (CDC) shows that the rates of gonorrhea, syphilis, and chlamydia — the three most commonly reported STDs in the United States— reached record highs between 2014 and 2015.

The CDC reported more than 1.5 million chlamydia cases, nearly 400,000 gonorrhea cases, and nearly 24,000 cases on primary and secondary syphilis during that year.

Young people, along with men who have sex with men (MSM), face the greatest risk of STD infection. Untreated STDs can lead to various health complications, including death.

STDs are also estimated to cost the U.S. healthcare system nearly $16 billion a year.

Jonathan Mermin, director of the CDC’s National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, sounded the alarm in a statement, saying, “We have reached a decisive moment for the nation. STD rates are rising and many of the country’s systems for preventing STDs have eroded. We must mobilize, rebuild, and expand services — or the human and economic burden will continue to grow.”

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Experts say it’s difficult to pin down one specific reason for the increase in STDs, though there are several possibilities.

“Some of this may have to do with the fact that in the past, a lot of sexually transmitted infections were decreasing because of people’s general fear of HIV, and when they took steps to prevent themselves from acquiring HIV, they also would by definition have some effect on other sexually transmitted infections as well,” Amesh A. Adalja, an infectious disease physician at the Center for Health Security at the University of Pittsburgh Medical Center, told Healthline.

“And what we’ve seen,” he added, “is that the destigmatizing of HIV over the last several years — which is a good thing because we have very effective treatments and HIV is no longer a death sentence and is a chronic illness that people can live normal lives with — has caused people to be less cautious during sexual encounters.”

Adalja also points to the digital revolution, where technology makes it easy to find sexual partners, as a possible culprit.

“There are a lot of easy ways for people to have casual sexual partners, where they don’t know their sexual history,” he explained. “These factors have all coupled together to be responsible for this rise in sexually transmitted infections.”

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For the most part, gonorrhea, syphilis, and chlamydia can be treated with antibiotics.

But, Adalja points out, drug resistant strains can make treatment difficult.

“You can’t speak about STIs without talking about the issue of drug resistant gonorrhea that’s happening,” he said. “So even if people do have access to medication, if they happen to be infected with a totally drug resistant strain of gonorrhea, it’s going to be very difficult to treat — and that’s just another example of how antibiotic resistance really threatens everything.”

The CDC says that one out of three antibiotic prescriptions in the United States is unnecessary. This overprescription of drugs leads to drug resistant infections, including certain strains of gonorrhea.

Another factor is limited access to medical treatment. The CDC reports that, due to budget cuts, more than 20 health department STD clinics have closed in just one year.

Adalja said this places the onus for diagnosis on primary care physicians.

“Many primary care providers are not adept at ordering [sexually transmitted infection] STI tests,” he said, “or knowing which tests to order, or being as comprehensive as they would be if they were seen at a dedicated STI clinic, so that may be playing a role.”

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Experts say that one of the best ways to prevent the spread of STDs is the use of condoms.

“When you have unprotected sex, you expose yourself to infection with a variety of microorganisms,” says Adalja. “The only way to protect yourself is to be very cognizant of the partners you have and to practice safe sexual practices as much as possible. In a way, STIs are easy to prevent because the behavior modification doesn’t cost that much money, but it does require people to be very proactive. I think what we’re seeing is that this has basically been failing over the last couple of years, and that’s why we have this upsurge in cases.”