The Implications of the Syphilis Outbreak in Houston for STI Transmission

The Houston Health Department recently reported a syphilis outbreak that is responsible for a 128 percent increase in cases among women, as well as a nine-fold rise in congenital syphilis in Houston and Harris County, Texas.

The spread is among a larger outbreak of sexually transmitted diseases, with syphilis cases rising nationally by what the Centers for Disease Control and Prevention (CDC) called an 'alarming' 32 percent from 2020 to 2021.

In response to the outbreak, the Houston Health Department is waiving all clinical fees for sexually transmitted infections at its health centers, and will expand the use of its HIV/STD mobile clinic to increase the number of community screening sites.

While the rising number of cases may be, experts agree that these statistics could be largely due to the COVID-19 pandemic’s stress on health care systems.

“Public health services were already struggling, but with the added stress from the Covid-19 pandemic, services related to education, testing, tracing and notification about STIs such as syphilis, became more difficult,” Amy Mersiovsky, DNP, MSN and Texas A&M University-Central Texas Department of Nursing Director and Chair told Health.

Mersiovsky explained that COVID-19 testing, treatment, and containment was the priority for a majority of medical funding and resources—many patients haven't received reproductive screenings and care due to clinics being closed.

'Without being diagnosed and treated, patients could be spreading the infection without knowing it,' she said.

Syphilis is a bacterial infection usually transmitted from skin-to-skin contact through vaginal or anal sex. While less common, it is possible to get it from oral sex.

According to Mersiovsky, direct contact with a canker sore is the primary way to spread the infection.

Screening tests for syphilis usually include either a rapid plasma reagin (RPR), which is a blood test or a venereal disease research laboratory (VDRL) test, which can be done on blood or spinal fluid.

Syphilis typically develops in stages, with the first stage involving painless sores on the mouth, genitals or rectum. The sore will last three to six weeks whether the patient receives treatment or not. If left untreated, those sores will heal and the second stage is characterized by a rash.

When it’s caught early on, syphilis is easily treatable with antibiotics—typically penicillin.

If the patient has had syphilis for a longer period of time or it’s in the secondary or later stage of syphilis, they will need three injections of antibiotics at weekly intervals.

Without treatment, the infection can lie dormant in the body for years or even decades before attacking the brain, nerves, eyes and other organs. While rare, it can cause deafness, blindness or death.

“There is a stigma around seeking treatment for STIs and a lack of access, especially for younger people or those without health insurance,” said family physician Alex McDonald, MD. “Often the initial ulcers are painless and heal on their own and people simply are not aware of the importance of being tested or evaluated.”

McDonald recommends correct and consistent condom use to significantly reduce the risk of all STIs.

The recent rise in syphilis cases in Houston is mainly attributed to pregnant women who passed the disease to their babies. This is referred to as congenital syphilis.

In 2016, there were only 16 reported cases, but in 2021, that number jumped to 151 cases.

Congenital syphilis can be prevented, but requires testing a pregnant woman for syphilis right away.

“Pregnant mothers should be tested during their first prenatal exam and at 28 weeks,” said Mersiovsky. “If the mother lives in an area with a high rate of syphilis, the screening should be repeated at delivery.”

Treatment depends on the treatment status of the mother plus clinical, laboratory, or x-ray evidence of syphilis in the infant.

Typically congenital syphilis and syphilis is treated with antibiotics, and if the mother tests positive, a shot of penicillin is given to her up to a month before delivery to make sure the baby is born healthy.

If the infant is diagnosed, a regimen of Penicillin G will be needed, said Mersiovsky. In addition, depending on the symptoms, the infant may need more treatment and testing.

If left untreated, syphilis in pregnant women can cause miscarriage or stillbirth. According to the CDC, 40 percent of babies born to women with untreated syphilis can die from the infection as a newborn or be stillborn.

Because syphilis can go undetected, it’s important to take preventative measures to ensure you and any sexual partners are safe.

Regardless of a syphilis outbreak in your area, McDonald recommends always practicing safe sex that includes wearing condoms, limiting the number of sexual partners you have, and routinely getting tested for STIs.

If you think you’ve been exposed to syphilis, or begin to notice symptoms like sores on the mouth or in the genital area, seek testing or medical attention as soon as possible. This will reduce the likelihood of transmission and severity of treatment needed. 

Pregnant women should speak with their healthcare provider regarding the recommendations for prenatal testing.

“This is critical to see if the fetus could have been exposed to syphilis,” said McDonald. “For babies who have contracted syphilis, treatment consists of penicillin IV for the first two weeks of their life.” 

It’s also important to still wear condoms and practice safe sex during pregnancy.

If you learn that one of your sexual partners has or may have syphilis, tell your doctor right away so you and your partner can be treated, and your baby can be protected.

If you test negative during your first or second trimester, you may need to be retested at the start of your third trimeter and at delivery, depending on how common syphilis infections are in the area that you live in.