Tuesday, March 11, 2008

One In Four

Of teenage girls in the U.S. have a sexually transmitted disease, according to a new study by the Centers for Disease Control and Prevention:

Federal health officials ask about different health and nutrition issues in the survey, which is conducted each year. The S.T.D. analysis was based on information collected in the 2003-04 survey.

Participants in the statistically based survey are chosen on a random basis. The survey contacted 838 women ages 14 to 19 who agreed to be tested for a sexually transmitted infection. Extrapolating from the findings, researchers estimated that 3.2 million teenage women are infected with at least one of the S.T.D.'s

I'm a little troubled with that "who agreed to be tested" part of the way the sample was arrived at, because we are not told if the girls who agreed to be tested are the same otherwise as the girls who perhaps didn't agree to be tested. It's possible that they are not the same, and if this is true the results should be generalized with a lot of caution.

In any case, this is what the study found:

The first national study of common sexually transmitted diseases among teenage women has found that one in four are infected with at least one of the diseases, federal health officials reported on Tuesday.

Nearly half of African-American teenage women were infected with at least one of the diseases monitored in the study — human papillomavirus (H.P.V.), chlamydia, herpes simplex type 2 and trichomoniasis, a common parasite.

That figure compared with 20 percent of white teenage women.

The two most common sexually transmitted diseases (S.T.D.'s) among all the women tested were H.P.V. at 18 percent and chlamydia at 4 percent according to the analysis, which was part of the National Health and Nutrition Examination Survey.

Among the infected women, 15 percent had more than one.

The Wall Street Journal warns the readers to not get into a panic over the findings, because

One in four American women between the ages of 14 and 19 has a sexually transmitted disease, according to the first national study to look at their prevalence, the CDC said.

That figure — alarming on its face — is worth a closer look.

The majority of those cases are infections with strains of a virus, human papillomavirus, that are associated with genital warts and cancer. But most people who get infected with HPV never know it, because the virus goes away without causing any health problems. "It is important to realize that most HPV infections clear on their own," noted a summary of the study that the CDC emailed to us.

Indeed, several common infections lumped into the big bin labeled "STD" can have mild or no effects on many patients — an issue that has prompted some leaders in the field to call for a dialing back of the nomenclature. The home page of the American Social Health Association says:

The concept of "disease," as in STD, implies a clear medical problem, usually some obvious signs or symptoms. But in truth several of the most common [sexually transmitted infections] have no signs or symptoms in the majority of persons infected. Or they have mild signs and symptoms that can be easily overlooked. So the sexually transmitted virus or bacteria can be described as creating "infection," which may or may not result in "disease." This is true of chlamydia, gonorrhea, herpes, and human papillomavirus (HPV), to name a few.

On the other hand the human papillomavirus is indicated as a possible cause for later cervical cancer, and teenage girls should get vaccinated against it.

But it is certainly true that one reason for the rise in the reported numbers of sexually transmitted diseases is that we now include more diseases under that category. Syphilis and gonorrhea have been famous for centuries, but chlamydia, herpes and the human papillomavirus have not.

Reading the reports about this study offers you one of those very odd experiences, like looking at that picture your friend shows you, of her new living-room couch, and there's a large pink elephant sitting on it, but you are supposed to discuss the shape and the pattern of the couch and pretend that the elephant isn't there at all.

In this case the pink elephant has to do with the way the teenage girls acquire the STDs they have. They don't get them from a public toilet ring. They mostly get them from teenage boys.

So what percentage of American teenage boys have sexually transmitted diseases? This is the next important study topic.