By Ann Hau M.D.:

Valentine's Day. Time for roses, chocolates, champagne and being with that special someone. But before celebrating with reckless abandon, information released this week from the U.S. Center for Disease Control and Prevention reminds lovers to proceed with caution and practice safe sex.

The report from the CDC describes how Neisseria gonorrhoeae, the bacteria that causes the sexually transmitted infection, or STI, gonorrhea, has become resistant to many forms of antibiotics since the 1930s. The bug continues to trouble disease experts as it morphs into strains that scientists call " multidrug-resistant gonorrhea."

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Lab studies show that cephalsporins, the current class of antibiotics used to treat gonorrhea, are becoming less effective at treating the disease. If this trend continues, cephalosporin-resistant gonorrhea could emerge in the U.S., like it has in Japan, France, and Spain. To help delay the emergence of this new super bug, the CDC made changes to guidelines for gonorrhea treatment. An injectable cephalosporin called ceftriaxone combined with an oral antibiotic is now the preferred treatment.

Gonorrhea is the second most commonly reported infectious disease in the United States. In 2011, more than 300,000 cases of gonorrhea were reported.

"The continued threat of multidrug-resistant gonorrhea makes protecting against [gonorrhea] more important than before," said Dr. Lindsey Satterwhite, an epidemiologist in the CDC's Division of STD Prevention.

Satterwhite emphasizes the need for safe sexual practices. "Wear a condom correctly, think about abstinence, practice monogamy, and get appropriate screening if you're high risk," she said. Left untreated, STIs can wreck havoc on the reproductive organs, causing severe medical problems and affecting the ability to have children later in life.

New statistics released from the CDC this week show that these preventative measures are especially important in young people ages 15-24, who account for 50 percent of new STIs. The statistics also reveal the economic burden of STIs. An estimated 20 million people are diagnosed each year in the U.S. Treating these infections cost the U.S. healthcare system nearly $16 billion in direct medical costs.

According to the CDC, the numbers reflect an ongoing, severe STI epidemic.

Satterwhite called this is a wake-up call for U.S. healthcare system. "People need to remember that all STIs are preventable, treatable, and many curable," she said. "There's lots of opportunity to save the nation's health and save billions of dollars a year in healthcare dollars, especially for the younger population."