by Bob Roehr
The Centers for Disease Control and Prevention (CDC) estimates that there were 19 million new sexually transmitted diseases (STDs) in the US in 2006, a modest increase from the previous year. Yet despite the increase, the tone of the November 13 news conference was decidedly less alarming than in recent years.
"STDs pose a serious and ongoing health threat to millions of Americans," said John M. Douglas, Jr. MD, director of the Division of Sexually Transmitted Disease (STD) Prevention at the CDC. "Young women, racial and ethnic populations, and men who have sex with men (MSM) are particularly hard hit by these diseases."
All of these infections can be treated, but often go undiagnosed and untreated. Each can result in serious health problems and increase the risk of HIV acquisition and transmission to others.
Chlamydia is the most common of the STDS, with over a million of the estimated 2.8 million new cases reported to the CDC in 2006. Reported new cases increased 5.6 percent over the previous year. A significant part of that increase was explained by increased screening for the disease and more sensitive diagnostic tests. African Americans were 46 percent of the reported cases, even though they constitute just 13% of the population.
Young women appear to be more vulnerable to chlamydia infection for both social and biological reasons. First, they are more likely to have more sex and more partners than older women, increasing their risk of exposure. Second, their cervix contains more of the specific type of cells that the infection targets; the number of those cells decrease with age. Finally, there is some evidence that the immune system can develop a response to better control new exposures once it has seen an infection and it has been cured with antibiotics.
Gonorrhea increased for the second year in a row, by 5.5 percent. This followed a steep decline in the 1980s and early 1990s, due in large part to safer sex practices, particularly the use of condoms, by gay men.
Dr. Douglas was particularly wary of a 31.8 percent increase in gonorrhea in the western part of the country over the years 2002 to 2006. A significant portion of that has been resistant to the fluoroquinolone class of drugs, which prompted a change in treatment guidelines earlier this year. The CDC now recommends treatment with the cephalosporin class of antibiotics.
Syphilis rates increased by 13.8 percent, but the total number of cases remains small, just 9,757 in 2006. And some of that increase represents aggressive screening activity such as the "Healthy Penis" campaign conducted by the San Francisco Department of Health.
The disease is unusual in that 64 percent of the reported cases were in men, particularly men who have sex with men. And a substantial portion–over half in cities that track coinfections–were in HIV positive gay men who are on antiretroviral therapy. Coinfection magnifies the course of syphilis, resulting in more rapid and severe progression, and increased ease of transmission.
Douglas said the magnitude of the increase of these STDs is similar to what has been seen over the last few years. "I don't think that the increases per say are major causes for alarm as much as the absolute numbers of chlamydia and gonorrhea infections, and the enormous disparities in these infections." He called the syphilis increases "real and concerning…a missed opportunity" to eradicate the disease.
"Up to 25 percent of women who are treated for chlamydia or gonorrhea become re-infected within the next three to six months," Douglas said. He emphasized the need for physicians to use "expedited partner therapy; basically sending treatment home with the patient without the partner receiving a formal medical evaluation."
Douglas was pressed on whether the high rate of STDs in MSM might reflect a cavalier attitude on the part of local departments of health because of the population affected. He thought not, pointing out that some of the biggest increases have been in New York and San Francisco where the health departments are very gay friendly. He said the hypothesis might have greater plausibility if the increases were occurring in more homophobic parts of the country.
He added, "Some of the traditional public health approaches, such as partner notification, have worked a lot less well among men in certain cities where the partners are not locatable, they are anonymous."
Many of these STDs show few if any noticeable symptoms in the rectum or penis. That is why the CDC recommends that sexually active gay men be screened at least once a year for gonorrhea, chlamydia, and syphilis.
