"Some people never show symptoms," said Epstein, a certified registered nurse practitioner who has worked at the Montgomery County STD clinic since 1992.

The Centers for Disease Control and Prevention has yet to calculate the 2010 average, but in 2009, Maryland's Chlamydia rate totaled 421.5 for every 100,000 people, while the national rate totaled 409.2 for every 100,000 people.

Also known as the "silent disease," Chlamydia tops the list of sexually transmitted diseases nationwide. Maryland's Chlamydia rate has exceeded the national average since at least 2005. The highest numbers are among young women between the ages of 15 and 24, according to the CDC.

The National Center for Biotechnology Information found that, nationwide, only 30 percent of women with Chlamydia show symptoms, while one in four men shows none.

DHMH reported 1,915 cases of Chlamydia in Montgomery County for 2009. Free screenings rest at the cornerstone of the county's STD prevention efforts. But true prevention, Epstein said, begins with protection.

Protection, she said, can be a hard concept for young people to grasp.

"sometimes they have this attitude of invincibility, you know? 'This won't happen to me,'" she said.

Bill Leeble, public information officer for the Charles County Health Department, agreed.

"It's never them, but always someone else," said Leeble.

"So, sometimes we use scare tactics," said Epstein, particularly warning teens about the symptoms and long-term effects.

Females stricken with the disease can experience painful sexual intercourse, abdominal pain or abnormal discharge. For men, common symptoms include testicular tenderness or penile discharge. Burning during urination remains a common symptom for both sexes.

The long-term effect for untreated females can prove especially damaging, including pelvic inflammations, ectopic pregnancy (pregnancy occurring outside the womb) or damaged Fallopian tubes, which can lead to infertility.

And the younger the female patients, Epstein said, the likelier they are to catch the disease because of their biology.

"The cervix is the place in women that Chlamydia likes best," she said. "in the cervix, there's what's called a junction transformation zone where cells align. Those cells are more exposed in younger women, and therefore more susceptible to germs."

Men are generally less affected, said Dr. Cynthia Mobley, medical director for adolescent and reproductive health at the Baltimore City Health Department.

Chlamydia is infection by a bacterium called Chlamydia trachomatis. it can be contracted orally, anally or vaginally, through unprotected sexual intercourse with infected partners. The bacterium travels to the rectum, vagina or penis, and in some cases, the eyes or mouth.

Epstein attributes high Chlamydia rates to nonchalant attitudes about sex.

"It's a cultural thing, and a lot of young women are stuck," she said. "these underage girls go to parties, get drunk and end up wondering what happened. 'I was partying. then all of a sudden I was in a bed. I have no idea how I got there,' they say."

Prevention for Chlamydia and other sexually transmitted diseases costs the U.S. $16.4 billion annually, according to the CDC. in Maryland, the STD budget is $1.5 million. and the DHMH found that about $1.1 million of that money was given to local health departments as grants for fiscal year 2010.

Baltimore's health department found that of the 23,747 cases reported in 2009, about 7,852 came from Baltimore City alone. The lowest numbers surfaced in Carroll and Garrett counties, at 156 and 28 respectively.

But even these numbers are misleading, Mobley said. Embarrassment or fear of repercussions, she said, often prevents teens from reporting their infections.

"The Baltimore City number is probably much higher than 7,852. Those are just the reported cases," she said. "That's because, with teenagers (especially), there's a stigma attached to STDs."

Dr. Charlotte Gaydos, professor of medicine for the Division of Infectious Diseases at John Hopkins University, agreed.

"how many teenagers do you think want that showing up on their parents' insurance bill?" she said.

Tracking Chlamydia cases that result from teen rape is even harder, said Garrett County clinician Heather Cooper.

"Those cases are difficult to quantify because, then, you're not only dealing with the stigma of rape, but you're dealing with the stigma of developing an STD as a result of that rape," said Cooper.

Reinfection rates pose yet another complication. The national reinfection rate hovers around 25 to 30 percent. and in many cases, Mobley said, the partner is not new, but usually the same person who infected the patient the first time. This leads to additional screening.

"when they come back in to get re-screened, we offer them information about 'I want the Kit,'" she said.

The "kit" is a free Chlamydia test that includes a swab for self-examination. it is available to teens in select states, including Maryland, and is an alternative for teenagers who need to get tested but might be shy about revealing their infection to their families, Gaydos said.

Teens can sign up for a kit online at iwantthekit.org and have it mailed to their address of choice. IWTK also has a Facebook page.

Gaydos praised IWTK as ideal for teenagers who need to get tested but lack the transportation or money to pay for it.

Aside from the kit, the Baltimore City Health Department shows waiting-room video screenings about STD prevention.

The Anne Arundel County Health Department pushes prevention with health fairs, brochures and teen summits. The department also partners with the county on after-school programs that stress abstinence, according to Michelle Brazil, the county's program manager for Infectious Disease Control. these programs, open to adolescents and their parents, "have been successful," Brazil said.

The Charles County Health Department targets high school juniors with a teen parenting class that includes a STD component. The program runs four times a year.

The National Center for Biotechnology advises sexually active women 25 and younger to undergo screenings annually.

Copyright © 2011 University of Maryland Philip Merrill College of Journalism