STOCKTON — More county residents had syphilis last year than in each of the past 20 years, according to information from the San Joaquin County Public Health Services.

San Joaquin County’s incident rate in 2017 was 50.9 syphilis cases per 100,000 people, which ranks second highest in the state only behind San Francisco, according to state data. The number of cases in the county last year was 381, which was a more than 40 percent increase from 2016.

Dr. Kismet Baldwin, a health officer with San Joaquin County Public Health Services, said she wants to “ring the alarm” about the rise of sexually transmitted disease (STD) cases in the county to make people aware, especially of the risks of syphilis.

“We really need the community to know that this is a problem,” she said.

There were so few syphilis cases in the early 2000s that it was thought it had almost been eradicated, Baldwin said. But since then, there’s been a steady increase of cases from year to year, which is a trend mirrored in the state and U.S.

Public health officials worry most about syphilis because it can be transmitted to a baby from the mother during pregnancy, and the state is seeing more cases of congenital syphilis, which can cause stillbirths, birth defects and long-term disabilities in babies.

There were 15 cases of congenital syphilis — three of which resulted in stillbirths — last year, said Hemal Parikh, HIV/STD program manager with Public Health Services. There are 16 cases so far this year.

According to the California Department of Public Health, there were more babies born with congenital syphilis in California in 2017 than there had been since 1995.

Health officials believe part of the reason there are more babies testing positive is due to the increase in women of childbearing age who have contracted the disease.

San Joaquin County has the highest rate in California for women ages 15-44 who have primary or secondary (the most infectious stages) of syphilis, Baldwin said.

Women who are treated during pregnancy run less risk of passing syphilis to their baby, Baldwin said. Syphilis treatment is one dose of penicillin unless the patient is in the latent stages, which would then require three doses three weeks apart. For a baby, however, treatment requires hospitalizations.

Baldwin said the practice in the past was to screen expecting mothers for STDs at the start of the pregnancy but now the guideline is to test three times, the last time right before delivery.

Public Health Services has pushed to educate healthcare providers and the public about the county’s STD problem, including launching a public awareness campaign.

Parikh said Public Health Services in the next three months will be testing 300 homeless people with a rapid-response syphilis test, as well as HIV screening.

While homeless people account for only 20 percent of syphilis cases, they typically lack access to medical care, he said.

Chlamydia and gonorrhea cases are also surging to the highest rates on record, according to Public Health Services.

Gonorrhea, which mostly affects men 25-29, saw an almost 20 percent increase, while chlamydia cases rose by 5 percent, according to county data. Women ages 20-24 account for most of the chlamydia cases.

So what’s causing the increase in STD cases?

There are some factors that play into it: education, homelessness, poverty, lack of access and even cellphone dating applications, but “nobody has a ‘This is exactly why it happened and this is how we need to fix the problem,’ ” Baldwin said.

The best way to prevent these STDs is condoms, which are available at Public Health Services, she said. If someone is not using condoms, they should feel comfortable asking their health providers to be screened.

“I think people often think, ‘It’s the homeless. It’s not the people I’m hanging out with,’ ” she said. “But it is the people you’re hanging out with. Everybody in the county is a possible person.”

For more information about STDs or how to get condoms, call (209) 468-3820 or visit https://bit.ly/2qG3hHF.

Contact reporter Almendra Carpizo at (209) 546-8264 or acarpizo@recordnet.com. Follow her on Twitter @AlmendraCarpizo.