Despite increased education and awareness, the rate of sexually transmitted diseases in America is slowly rising. In fact, STDs cost the U.S. health care system roughly $16 billion each year, according to the Centers for Disease Control and Prevention (CDC).

Infection rates aren’t spread evenly throughout the U.S. or across different age groups. Young people between 15 and 24 represent half of all new STD cases. STD rates also vary widely by state—the state with the highest syphilis rates (Georgia) reports 47.5 times more infections than the state with the lowest prevalence (Montana). Read on to see which states have the highest and lowest rates.

STDs are easily confused with sexually transmitted infections (STIs), which are sexually transmitted viral or bacterial infections that have not resulted in disease. For example, human papillomavirus (HPV) is an STI that sometimes results in genital warts, an STD. The most common STDs, in order of prevalence, are chlamydia, gonorrhea, and syphilis—all of which can be cured with the right medication.

READ MORE: The Cost of STIs

Chlamydia, the most commonly reported STD in the U.S. for the past 20 years, often goes unnoticed because it is usually asymptomatic. However, untreated chlamydia can cause pelvic inflammatory disease (PID), a condition that damages the female reproductive system and can lead to infertility. The CDC recommends that women under 25 be tested annually for chlamydia. While most people with chlamydia have no symptoms, an abnormal discharge and burning when urinating are warning signs in both sexes.

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Gonorrhea was the most common STD in the U.S. until the implementation of a health initiative by the federal government in the mid-70s, which led to drastically reduced rates. Like chlamydia, gonorrhea is also often asymptomatic and can lead to PID if left untreated. Gonorrhea warning signs include burning when urinating and abnormal discharge in men and women.

Syphilis is less common than chlamydia and gonorrhea, but is potentially the most serious of the three if left untreated. Syphilis exists in a series of distinct stages and can be treated at any stage, but damage is permanent. The late stage of syphilis can take 10 to 30 years of latency to develop, but symptoms include paralysis, dementia, and blindness. The first sign of syphilis is a single painless sore on the genitals lasting 3 to 6 weeks, after which more sores and a rash appear on one or more parts of the body.

To determine the best and worst states for STDs, CDC data on chlamydia, gonorrhea, and syphilis were obtained. States were ranked according to prevalence of each, and then ranks were added together to find an overall score. Using this system, the state with the lowest score is the “best state” for STDs, and the state with the highest is the “worst state” for STDs. In the case of an equal score, or tied ranking, each state’s chlamydia ranking was used as a tiebreaker. This is because chlamydia cases are by far the most commonly reported—over four times more common than the next most prevalent STD, gonorrhea.

READ MORE: STD Statistics by State

Best States for STDs

1. West Virginia
(48th for chlamydia, 41st for gonorrhea, 49th for syphilis)
2. Maine
(49th for chlamydia, 44th for gonorrhea, 43rd for syphilis)
3. Vermont
(46th for chlamydia, 46th for gonorrhea, 44th for syphilis)
4. Utah
(47th for chlamydia, 45th for gonorrhea, 42nd for syphilis)
5. Wyoming
(37th for chlamydia, 50th for gonorrhea, 46th for syphilis)
6. Montana
(35th for chlamydia, 48th for gonorrhea, 50th for syphilis)
7. Idaho
(45th for chlamydia, 49th for gonorrhea, 38th for syphilis)
8. New Hampshire
(50th for chlamydia, 47th for gonorrhea, 30th for syphilis)
9. Nebraska
(38th for chlamydia, 32nd for gonorrhea, 48th for syphilis)
10. Minnesota
(43rd for chlamydia, 36th for gonorrhea, 34th for syphilis)

READ MORE: The Healthiest Places in America

Worst States for STDs

10. North Carolina
(10th for chlamydia, 6th for gonorrhea, 24th for syphilis)
9. New York
(11th for chlamydia, 16th for gonorrhea, 7th for syphilis)
8. Texas
(13th for chlamydia, 13th for gonorrhea, 6th for syphilis)
7. Illinois
(9th for chlamydia, 10th for gonorrhea, 8th for syphilis)
6. Arkansas
(7th for chlamydia, 7th for gonorrhea, 9th for syphilis)
5. South Carolina
(5th for chlamydia, 4th for gonorrhea, 13th for syphilis)
4. Alabama
(3rd for chlamydia, 3rd for gonorrhea, 15th for syphilis)
3. Georgia
(8th for chlamydia, 5th for gonorrhea, 1st for syphilis)
2. Mississippi
(1st for chlamydia, 1st for gonorrhea, 11th for syphilis)
1. Louisiana
(4th for chlamydia, 2nd for gonorrhea, 3rd for syphilis)

Lacie Glover writes for NerdWallet Health, a website that empowers consumers to find high quality, affordable health care and insurance.