Iowa generally ranks among the states with the lowest rates of several common sexually transmitted disease. But before Iowans celebrate being the picture of sexual health, not all the news is good in our state. In fact, Iowa has seen an increase in several STDs over the past few years, which mirrors a trend happening nationally. The U.S. has seen four straight years of increased rates of chlamydia, gonorrhea, and primary and secondary syphilis.

Which sexually transmitted diseases and infections are most common in Iowa, how have rates fluctuated over time, and which locales around the state have the highest concentrations of STDs? To answer those questions, we’ll examine data from the federal Centers for Disease Control and Prevention and the Iowa Department of Public Health.

Chlamydia Rates in Iowa

More than 14,000 people were diagnosed with chlamydia in Iowa in 2018, and the state’s population-adjusted rate places Iowa in the 32nd position among all 50 states. Iowa’s chlamydia rate is about 12% lower than the national rate.

Chlamydia infections per 100,000 people, bottom 25

Connecticut 496.3
Virginia 488.3
Florida 485.2
Wisconsin 485
Colorado 481.3
Hawaii 479.5
Iowa 467
Kansas 466.2
Nebraska 450.7
Oregon 450
Minnesota 444
Washington 442.2
Pennsylvania 441.5
Montana 437.4
Kentucky 435.4
North Dakota 432.5
Massachusetts 425.7
New Jersey 392
Idaho 368.4
Wyoming 365.8
Maine 342.1
New Hampshire 330.5
Utah 323.7
Vermont 297.5
West Virginia 226.1
Total 528.8

The rate of chlamydia in Iowa has increased every year since 2014, and it’s risen by nearly 50% since 2008.

Iowa chlamydia rate by year (cases per 100,000 people)

2008 314
2009 313
2010 350
2011 363
2012 365.7
2013 361
2014 376
2015 390
2016 416
2017 443.3
2018 467

No Midwestern state ranks among the 10 states with the highest chlamydia rates, and Iowa comes in near the middle of the region. Iowa’s rate is about 20% lower than regional leader and next-door neighbor Illinois.

Chlamydia infection rate, Midwestern states (cases per 100,000 people)

Illinois 589.9
Missouri 536.4
Ohio 528.6
Indiana 514.2
South Dakota 512.7
Michigan 511.9
Wisconsin 485
Iowa 467
Kansas 466.2
Nebraska 450.7
Minnesota 444
North Dakota 432.5

 Gonorrhea Rates in Iowa

Iowa just barely ranks in the bottom half of the states when it comes to how common gonorrhea is in the state, and Iowa’s population-adjusted rate is only about 10% lower than the overall U.S. rate.

Gonorrhea infections per 100,000 people, bottom 25

Iowa 154
Florida 153.7
Colorado 151.1
South Dakota 149.1
Virginia 143.3
Minnesota 142
Nebraska 139.1
Washington 136
Wisconsin 135
North Dakota 127.4
Oregon 121.3
Pennsylvania 119.2
Connecticut 109.4
Massachusetts 106.5
New Jersey 105.5
Rhode Island 102.9
Hawaii 95.1
Utah 81.2
Montana 75
West Virginia 70.8
Wyoming 70.4
Idaho 58.6
Maine 46.6
New Hampshire 38.4
Vermont 32.5

The prevalence of gonorrhea has nearly tripled in Iowa over the course of the past decade, with a 28% spike recorded between 2017 and 2018 alone.

Iowa gonorrhea rate by year (cases per 100,000 people)

2008 57
2009 55
2010 60
2011 65
2012 65.1
2013 48
2014 53
2015 72
2016 83
2017 119.9
2018 154

Ohio is the only Midwestern state among the 10 states with the highest gonorrhea rates, and Iowa’s rate is more than 25% lower than Ohio’s.

Gonorrhea infection rate, Midwestern states (cases per 100,000 people)

Ohio 216.3
Missouri 214.8
Illinois 186.4
Indiana 177.5
Kansas 156.3
Michigan 154.7
Iowa 154
South Dakota 149.1
Minnesota 142
Nebraska 139.1
Wisconsin 135
North Dakota 127.4

Syphilis Rates in Iowa

Iowa boasts the fifth-lowest rate of primary and secondary syphilis infections in the country, and the national leader, Nevada, has a rate more than 7 times higher than Iowa’s.

Primary and secondary syphilis infections per 100,000 people

Highest
Nevada 20
California 17.1
Georgia 14.5
Louisiana 14.5
Arizona 13.1
Maryland 12.2
New York 11.9
Florida 11.6
North Carolina 10.6
Mississippi 10.4
Total 9.5
Lowest
Utah 3.7
West Virginia 3.4
New Hampshire 3.2
Connecticut 3.1
Wisconsin 3
Iowa 2.7
Nebraska 2.3
Vermont 2.1
Alaska 1.8
Wyoming 0.7

Iowa bucks the national trends when it comes to primary and secondary syphilis, and the state is one of only four to record a decrease in the rate since 2013. Still, the rate has risen over the past decade.

Iowa primary and secondary syphilis rate by year (cases per 100,000 people)

2008 1
2009 1
2010 1
2011 1
2012 2.2
2013 3.5
2014 2.4
2015 2.4
2016 3
2017 3.2
2018 2.7

No Midwestern state ranks in the top 10 for syphilis prevalence, and Iowa has the second-lowest rate in the entire region.

Primary and secondary syphilis infection rates, Midwestern states (cases per 100,000 people)

Illinois 9.6
Missouri 8.3
Ohio 6.3
North Dakota 5.8
Minnesota 5.5
Michigan 4.8
Indiana 4.8
Kansas 4.6
South Dakota 3.8
Wisconsin 3
Iowa 2.7
Nebraska 2.3

HIV & Other STD Rates in Iowa

HIV

More than 125 people were newly diagnosed with HIV in Iowa in 2017, which reflects a decline of nearly 10% from the previous year. Still, 2016 marked an all-time high for HIV diagnoses in Iowa. See HIV test options.

Hepatitis B & C

Cases of acute hepatitis B occur at lower rates in Iowa than in the U.S. generally, with Iowa’s rate standing at about 70% lower than the overall national acute hep B rate. Additionally, the hep B rate in Iowa has fallen by about 40% in recent years. Acute cases of hepatitis C have not been reported by the state in several years, but during the most recent reporting year, 2012, Iowa’s rate was more than 80% lower than the national rate reported that year. See hepatitis test options.

HPV

It’s virtually impossible to pinpoint the number of people who are infected with human papillomavirus at any given time. That’s partly because the virus is so incredibly common (most sexually active people will contract it at some point) and partly because the vast majority of those infected show no symptoms and so never get tested. But some strains of HPV, when untreated, can lead to several types of cancer, including cervical, penile and anal cancers. So examining the rate of HPV-related cancer can help us understand the scope of the HPV crisis in a given state. Iowa’s HPV-caused cancer rate is about 12.3 per 100,000, slightly higher than the national median of 11.7 per 100,000. See HPV test options.

STDs in Iowa Cities & Counties

While the state has a whole generally ranks near the middle or bottom of most STD lists, several areas of the state, including the Des Moines and Cedar Rapids metro areas, account for an outsized proportion of cases, and still other counties have higher infection rates than others.

Chlamydia

Nearly 1 in 4 chlamydia cases in Iowa in 2018 were diagnosed in people living in the Des Moines metro area, and Cedar Rapids added another nearly 10% of all cases.

Iowa counties by chlamydia infection rate (cases per 100,000 people), top 10

Black Hawk 757
Johnson 684
Woodbury 682
Des Moines 665
Webster 664
Polk 650
Wapello 645
Story 643
Union 610
Scott 583

Gonorrhea

Des Moines and Cedar Rapids combined to account for more than 2 in 5 gonorrhea cases in the state.

Iowa counties by gonorrhea infection rate (cases per 100,000 people), top 10

Pottawattamie 336.2
Woodbury 334.9
Des Moines 319.7
Black Hawk 309.8
Polk 283.7
Wapello 282.5
Webster 196.7
Linn 195.9
Scott 185.5
Johnson 148.8

Primary and secondary syphilis

More than 25% of primary and secondary syphilis infections were diagnosed in people living in the Des Moines metro area.

Iowa counties by primary and secondary syphilis infection rate (cases per 100,000 people), top 10

Mahaska 18
Poweshiek 16.4
Fremont 14.4
Hardin 11.7
Emmet 10.6
Pottawattamie 8.6
Harrison 7.1
Page 6.6
Marion 6
Des Moines 5.1

Conclusion

It’s true that Iowa ranks near the middle (and sometimes near the bottom) when it comes to how common several sexually transmitted diseases and infections are. But it’s also a fact that the state has seen an increase in almost all STDs over the past decade, so it’s not all good news for Iowa. Preventing the spread of sexually transmitted diseases means being responsible in your sex life, and getting tested for a range of sexually transmitted diseases and infections is a major part of that. Most sexually active people will contract at least one STD over the course of their lifetimes, so a positive result is nothing to be ashamed of. After all, knowing your STD status means you have the power to prevent the disease from spreading further.

Additional References

Note: Some states have published more recent data for chlamydia, gonorrhea, and primary and secondary syphilis. For states in which that’s the case, we have substituted the individual state data for 2018 and used that in our rankings, while other states’ rankings are based on 2017 numbers. In some cases, we assume that when the full national dataset is published by the CDC, states’ positions relative to other states will change some, though those changes are unlikely to be dramatic, since the CDC data comes from the states.