Photo: Bruce Stidham/Kaiser Health News

Syphilis rates in the United States have been going up for about 20 years — along with other sexually transmitted infections.
PEOPLE spoke toDr. Edward Hook— professor at the University of Alabama at Birmingham and director of the STD Control Program for the Jefferson County Department of Health — about the resurgence, a well as what syphilis is and why there’s a recent influx in cases of the sexually transmitted infection.
What is syphilis?
Syphilis is a bacterial infection that is usually spread through sexual contact, according to theMayo Clinic, and usually presents as painless sores that spread the disease.
Because the sores don’t hurt, they often go undetected. However, theCDC saysthat while the sores will last 3-6 weeks regardless of treatment, it’s important to seek medical care to prevent the infection from progressing to the next, more dangerous stage.
At its early stage, syphilis can be cured with asingle doseof antibiotics. But “without treatment, syphilis can severely damage the heart, brain or other organs, and can be life-threatening.”
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Why are syphilis cases rising?
“Syphilis was lowest to start with in terms of the total population so it had the most room for increasing,” Hook notes.
Part of the reason cases of syphilis — as well as other STIs — are rising is because public health efforts to control these diseases are underfunded.
“In the past 20 years, the amount of money that goes to the CDC for STD control has remained level because of inflation. That means that the buying power of that funding is 40% less than it was 20 years ago. So it seems to me that the lack of resources is another important contributor to this problem.”
Additionally, syphilis cases are no longer present primarily among men who have sex with men.
“The current syphilis epidemic, of the past 10 or 15 years, started amongst men who had sex with other men,” he says. “But no surprise, it has then moved beyond men who have sex with men to involve men who have sex with women, and women who have sex with men, and other groups as well because people don’t exclusively partner with one kind of sex partner or another.”
Why are cases of syphilis in women increasing?
For example, theHouston Health Departmentreported this week that there was a 128% increase in congenital syphilis in Houston and Harris County — a rise that is similar to that of other cities across the United States.
“Congenital syphilis rates are now higher than they’ve been in the United States in more than 25 years. There are several reasons for that,” Hook says. “One is that this mirrors the general increase in syphilis and the movement of the syphilis epidemic from men who have sex with men into heterosexual population.”
“Second is that women with syphilis are disproportionately ethnic minorities, racial minorities, and those are people who have less ready access to healthcare than other populations,” he continues. “So, if you look at the simplest rates in the United States, you’ll see that the rates have gone up disproportionately amongst Hispanic women and Black women — the same groups who have other challenges with regards to access to healthcare, prenatal care, etc.”
Although cases in women are rising, Hook assures that these rates do not mean that women are more susceptible to syphilis. “It’s not a vulnerability issue,” he stresses. “There is no data whatsoever to suggest that one group or another is more vulnerable to acquiring syphilis than others.”
Pregnant woman.Getty

What is the key to decreasing overall syphilis cases?
Hook emphasizes that the national rate of syphilis cases could easily be lowered if there was greater investment in public health in the United States.
That investment involves increasing availability of and accessibility to preventive and care services, increasing education about screening and treatment, and focusing those efforts on underserved populations.
He adds, “The rates got so low that people said, ‘We’re in good shape, we can now reallocate resources to other purposes.’ And they did. The disease smoldered for a while, and then came back in a new vulnerable population this time, men who had sex with men.”
How often should people get tested for syphilis?
“That answer is different for everybody,” Hook admits. “In general, the more partners a person has, the more often they should be checked. We would suggest that everybody be checked at least once. For the people who are in stable, monogamous relationships and are confident that their partners are similarly monogamous, one test should be enough. If there are questions about monogamy, testing periodically — perhaps once a year — is reasonable. For people who have more than three, four sexual partners in a year, testing as frequently as every six months might be a good idea.”
source: people.com