Sexual Healing
For decades, Baltimore has struggled to contain swift-moving outbreaks of sexually transmitted infections, and scored some successes. Will creativity and new strategies be enough for the future?
A decade ago, Baltimore endured a syphilis epidemic of astonishing proportions. The city's infection rate peaked at slightly more than 100 cases per 100,000 population, soaring to 18 times the national average and reaching a level usually found only in developing countries.
When those numbers landed on the front page of The New York Times, Baltimore became the punch line in a long string of bad jokes by TV talk show hosts. But more than civic pride was at stake: Over a two-year stretch, 115 babies in Baltimore were delivered with congenital syphilis contracted from infected mothers. Some of those infants emerged stillborn. Others began life facing serious health complications and cognitive impairments.
"To me, that's one of the worst public health statistics you can have, and Baltimore had it—real cases of dead babies because someone never got a shot of penicillin," says Emily Erbelding, MD, MPH '95, associate professor in the School of Medicine's Division of Infectious Diseases, with joint appointments in Epidemiology and Population, Family and Reproductive Health (PFRH).
The city quickly launched a major public health offensive against an infection that, if untreated, can cause an array of serious and sometimes fatal health complications. Armed with an infusion of resources from federal and state sources, the city Health Department added clinical staff, bolstered surveillance efforts and launched new outreach programs.
Along the way, the department expanded its longstanding partnership with the Bloomberg School. The city and the School now share several employees—including Erbelding, who is the department's chief of clinical services for sexually transmitted infections—in joint-appointment arrangements. Other faculty work closely with the Health Department to find grants and launch test initiatives that are evaluated rigorously.
The work is paying dividends: Today, Baltimore's syphilis rate is a quarter of what it was a decade ago, and gonorrhea rates are down 45 percent, from 1,000 cases per 100,000 population in 1995 to 550 in 2005.
But progress is one thing, success another. Compared with other cities, Baltimore still has disproportionately high rates of sexually transmitted infections (STIs).
"The numbers have improved since the late 1990s, but it's not like we're in a position to declare victory," says Erbelding. "You always have the feeling in this field that when you let your guard down, there's a chance infections are going to explode again."
Most STIs thrive on the edges of society. The behavioral patterns that fuel infection rates, such as prostitution and drug abuse, are inextricably linked with social issues, such as poverty, homelessness and incarceration.
To illustrate the complexity this creates, Jonathan Zenilman, MD, scrawls a wavy line representing the nation's syphilis rates over the last 70 years. Zenilman is a professor of Medicine and chief of the Division of Infectious Diseases at Johns Hopkins Bayview Medical Center and has joint appointments at the Bloomberg School in International Health, Epidemiology and PFRH.
The line starts out at a high level in the 1940s, then sweeps down in a slope that signals the arrival of penicillin. From there, it settles in a low, lingering rate until popping up in the 1970s ("Gay liberation," Zenilman hypothesizes.), dropping down in the 1980s ("AIDS. People changed their sexual behaviors.") and popping back up again in the 1990s. ("At this point, syphilis is largely an African-American disease, fueled by crack cocaine.")
But such broad national trends say only so much about local realities. CDC experts tried to pin the 1990s epidemic in Baltimore on crack cocaine, but local experts never bought it. "Out in the clinics [in Baltimore], we never saw that many crack users," Zenilman says. Several theories surrounding the epidemic are discussed in The Tipping Point, a bestseller by journalist Malcolm Gladwell. Zenilman is quoted advancing a theory that a severe recession in the early 1990s led to funding cutbacks that gutted essential public health services in Baltimore.
Zenilman likes one of the other theories advanced in Gladwell's book, too, this one developed by the maverick Colorado-based epidemiologist John Potterat. It centers on Baltimore's decision to raze several high-rise public housing projects during the 1990s.
"These places were densely populated, with well-established and quite limited social networks, as well as a lot of disease," Zenilman says. "All of a sudden these folks were spread out all over the city. Guess what? They found new sex partners. So this epidemic may have been an unintended collateral effect of tearing down those horrible projects."
The bottom line? When dealing with STIs, raw numbers and historical cycles sometimes tell you next to nothing about what's actually going on in the streets of a specific city and what strategies public health practitioners need to employ.
"These diseases are always such a complex integration of disease, social science, behavior and public policy," Zenilman says. "That's what makes this field so fascinating."
So how has the city of Baltimore achieved a striking, if incomplete, measure of progress since its syphilis epidemic peaked?
One key strategy is upgraded outreach efforts to at-risk populations, says Laura Herrera, MD, MPH '05, a former Hopkins faculty member who is now chief medical officer at the city Health Department. The department bolstered its surveillance staff and outfitted mobile vans with diagnostic equipment.
The department also worked with Jonathan Ellen, a Pediatrics professor at the School of Medicine with joint appointments in Epidemiology and PFRH, to upgrade its informatics capabilities and employ geographic information systems.
"We're not doing our outreach by looking for high morbidity ZIP codes anymore," Herrera says. "Our outreach is based on indexed cases and interviews. We target individual houses where we know there's been commercial sex work activity. We target particular corners where we know the exchange of sex for drugs is going on. And we do this in a turnaround time that can be as short as 24 hours. We're getting to areas while they're still hot."
Last year, the Health Department lobbied successfully in the state legislature to make Baltimore one of the first jurisdictions in the nation to employ expedited partner therapy (EPT), in which a patient diagnosed with gonorrhea is given a prescription to take to his or her partner, even though that partner has not yet seen a health care provider. The program is only a few months old, but preliminary data are encouraging, says Joshua Sharfstein, Baltimore's health commissioner.
The clinics are geared to deliver services that make the most of the surveillance and outreach improvements. "They're a critical safety net," Erbelding says. "You can't rely on the private sector here. Most of our patients don't have insurance, so they'd be self-pay patients, and it might take them three weeks to get an appointment. That's just unacceptable. Someone could transmit to five or 10 or 20 people in that time."
Two other STIs are disproportionately high in Baltimore, but the trend lines are harder to read for chlamydia and HIV. Chlamydia is an infection contracted mostly by adolescents and young adults. In most cases, it has no symptoms, and the infection often goes undiagnosed. But it has been linked to health complications including pelvic inflammatory disease, which, in turn, can cause infertility and tubal pregnancy.
Screening for chlamydia has increased dramatically in the last 15 years. This clouds the long-term trends for the infection, with more and more cases getting diagnosed that previously went undiscovered, says Charlotte Gaydos, DrPH '93, MPH '89, an associate professor of Infectious Diseases with the School of Medicine who has joint appointments in Epidemiology and PFRH.
In 2005, Baltimore's Health Department put the city's chlamydia rate at roughly 1,000 per 100,000 population. "When all these screening efforts began, we initially made a nice dent among high school girls," Gaydos says. "But since then, it's just been level, level, level—to be frank, things are not going that great."
One key to progress will be expanded educational interventions. In a forthcoming paper, Gaydos will evaluate an effort to identify at-risk youths through clinics at five Baltimore high schools and then target them with educational messages about the disease, its risks and prevention strategies. That effort successfully reduced prevalence among its participants, she says.
Gaydos is also involved in gauging the effect of a Web-based project that delivers educational messages and enables users in Maryland, Virginia and Washington, D.C., to order a free self-administered vaginal swab test for chlamydia. Users at the website are asked to complete an extensive survey.
HIV infections in the U.S. peaked in the mid-1980s at about 160,000 cases per year and eventually dropped to about 40,000 per year after 1990. So, too, in Baltimore, where an estimated 16,000 people are living with HIV and new cases arise at the rate of about 1,000 per year.
"Some people might look at this and say it's a public health success, because the rate is lower than it was," says David Holtgrave, PhD, chair of Health, Behavior and Society. "But we don't seem to be making progress in getting infections to drop below the new level, so other people might look at this and see a failure."
Actually, it's both. Holtgrave estimates that there would have been between 200,000 and 1.5 million additional cases of HIV nationally between 1985 and 2000 in the absence of public health prevention efforts. But further reductions in the infection rate may well require additional resources to expand proven strategies and develop new techniques. Baltimore especially needs help: A recent federal study found that metropolitan Baltimore has the second-highest rate of new AIDS cases in the nation. (Miami is first.)
But here, too, resources are getting harder to come by. In a recent paper, Holtgrave examined funding patterns in HIV prevention efforts and found that CDC spending has dropped by 19 percent in real dollars since 2002.
"So that means one in five of the prevention dollars we had just a few years ago is gone," he says.
The timing couldn't be worse. There has been a recent upswing in HIV/AIDS cases nationally among men who have sex with men.
"Twenty years ago, people in many communities were going to a funeral a week," Holtgrave says. "This new generation, they haven't seen that to the same extent."
To reach this younger audience of gay men, Holtgrave favors an array of classic public health strategies—outreach, surveillance, testing, counseling, behavioral interventions and treatment—combined with general public education.
But none of these strategies will bear fruit if resources continue to dwindle. A few years back, Holtgrave compared CDC spending on HIV prevention with incidence rates for the infection.
"What we found was that in the early 1980s, the epidemic was driving spending," he says. "But after 1986, once there were substantial resources in the system, it was the other way around. You could predict incidence a few years out pretty much just by looking at resource levels."
He pulls out a graph of HIV incidence rates and prevention spending patterns over the decades and points to the recent downward tick in resources. "It's too early to know for sure if this is going to turn out to represent the start of a jump in infection rates," he says, "but sadly, I wouldn't be at all surprised if that's what it turned out to be."