Clinicians diagnosed Sacramento County teen girls and young women with more sexually transmitted diseases, or STDs, last year than ever. At the same time, the county's teen birthrate dropped to a historic low.

STD specialists worry that the seeming contradiction between rising STD rates and declining teen pregnancies may have a troubling explanation: that girls are using hormonal contraceptives like the pill, but young couples aren't using condoms.

"We need to get boys to use condoms more consistently," said Anna-Barbara Moscicki, a professor of pediatrics at the University of California at San Francisco, who has published extensively on sexually transmitted infections.

More than four of every 100 women in Sacramento County between ages 15 and 24 were diagnosed with chlamydia or gonorrhea in 2010, according to new data from the California Department of Public Health.

That's a 12 percent jump from the year before – a spike that one local women's health care specialist called "a silent epidemic."

Though easily treatable with antibiotics, chlamydia and gonorrhea sometimes exhibit few symptoms and, if left undetected and untreated, can cause serious problems, including infertility.

The rise in 2010 gives the county the highest gonorrhea infection rate among young women in the state, and the second-highest rate for chlamydia infection, behind San Francisco. Gonorrhea infections among young women here were almost 190 percent higher than the statewide average last year, while chlamydia infections were about 60 percent higher.

Chlamydia is diagnosed more often in girls than in boys. Still, physicians diagnosed just over one of every 100 young men in Sacramento County between ages 15 and 24 with chlamydia last year, the fourth-highest rate in the state. Sacramento County's gonorrhea infection rate last year among males in that age bracket was the third-highest rate in California.

Why Sacramento's rate is higher than other places "is definitely an enigma that we're trying to work through," said Cassius Lockett, the county's chief epidemiologist.

The corresponding 23 percent decline in the birthrate among young women doesn't surprise local clinic workers. They say many young people use birth control but regularly skip condoms – a risk taken out of teenage carelessness and widespread ignorance about STDs and how they spread.

Jacqueline John, manager of outreach, education and prevention at the nonprofit CARES Clinic in midtown Sacramento, said, "It floors me on a regular basis how little people actually know."

Misinformation rampant

It's easier for today's girls to prevent pregnancy than it has been in the past, and they're doing so, said Moscicki. Young women have access to a variety of contraceptives their parents did not, including the vaginal ring and hormonal shots, she said. But those contraceptives don't help prevent the spread of STDs.

In fact, that very security about pregnancy may make young couples cavalier about STDs, said Kiara Hill, a 22-year-old student at California State University, Sacramento, and a peer educator with CARES.

"As a young woman, a lot of times we think the worst thing that could happen to us is an unplanned pregnancy," Hill said. "We think, 'I'm on birth control, I know he won't (cheat on me), so it's OK.' "

Plus, many young people are dangerously misinformed about STDs, Hill and others said.

The most common misconception among teen boys and young men at the Effort Oak Park Community Health Center – laughable if it weren't so harmful – is that condoms are too small to fit them, said licensed midwife Tanya Khemet, who does STD testing for adolescents there. Others think they can tell if a sexual partner has an infection by looking at the person's genitals or simply based on his or her reputation.

Khemet and CARES educators said they know of many youths who have oral or anal sex instead of vaginal to avoid pregnancy, not considering that they can contract STDs that way, too – in some cases even more easily.

"What I see are teenagers who are poorly informed about the risk and also who don't know where to go for services," Khemet said.

It's unclear if testing could partly account for the STD spike. Screening methods have improved in recent years, becoming less invasive and therefore more appealing to youths, Moscicki said. More testing can translate into higher reported infection rates.

On the other hand, when youths have poor access to medical care, they aren't tested for long stretches of time and can continue to spread their infection. Sacramento County has closed four of its five public health clinics – which provided STD screening and treatment – due to budget cuts in the past three years.

Poor access to health care partly explains why STD rates are higher among young minorities, Moscicki said. In Sacramento County, infection rates have jumped across all races, but the increases have been highest among blacks and Asian Americans.

As for why Sacramento matches or beats big-city San Francisco in infections, John and her colleagues at CARES have a hunch.

It's precisely because this is a smaller city, and at the same time a regional crossroads, they say. People travel to Sacramento from an area stretching as far as Chico and Reno, possibly bringing infections with them.

Yet within Sacramento, social circles are small. There are only so many young people here, so they end up choosing their sexual partners from within the same small community, passing STDs around in a sort of echo chamber of infection.

Prevention budget tight

Staci Syas, coordinator for the county's HIV and communicable disease prevention program, wants to turn the tide on STDs in Sacramento quickly. She worries these rampant infections could produce a wave of young women who, when they eventually want to get pregnant, discover they can't.

Last spring she used a $20,000 grant from the federal Centers for Disease Control and Prevention to run an awareness campaign, placing posters and information around college and high school campuses. But that was one-time money, and without it Syas said her total budget for STD prevention is under $50,000 a year.

Syas will continue her usual efforts, running training sessions for local teachers and the staffs of community organizations that serve youth, and doing educational presentations at high schools and colleges. She's hoping to start doing more testing on high school campuses. But she said that's all her finances will allow.

"We need a more systemic way of comprehensively addressing it in our community," Syas said. "And we have not had the resources to do that."

The numbers so far this year bear that out.

State records show Sacramento County is on track to see 10,800 cases of chlamydia and gonorrhea diagnosed among men and women of all ages in 2011 – more than last year's 10,300 and an all-time high.

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