Blacks were disproportionately affected by sexually transmitted infection rates in 2007, including chlamydia rates that reached a record high and syphilis rates that increased for the seventh consecutive year, according to a CDC report released on Tuesday, Reuters Health reports (Dunham, Reuters Health, 1/13).

The report found 1.1 million chlamydia diagnoses were reported in 2007. The chlamydia rate was 370 reported cases per 100,000 people in 2007 -- a 7.5% increase since 2006.

Reported gonorrhea diagnoses -- which peaked in the 1970s at one million and then declined until a few years ago -- totaled 355,991, or 119 reported cases per 100,000 people in 2007. The rate was similar to that reported in 2006.

The syphilis rate continued to rise in 2007, as it has since 2000, with 11,466 diagnoses reported, or 3.8 cases per 100,000 people. This marks a 15% increase from 2006 (Engel, Los Angeles Times, 1/14).

Black women ages 15 to 19 have the highest rates of chlamydia and gonorrhea. Gonorrhea rates for blacks overall were 19 times higher than for whites, according to the report. Blacks make up 12% of the U.S. population, but account for about 70% of gonorrhea cases and nearly 50% of chlamydia and syphilis cases, the report said (Reuters Health, 1/13). Minorities have been disproportionately affected by STIs in previous year reports, with American Indians Alaska Natives and Hispanics at a lesser extent, according to the Times.

Public health officials said the disparities can be attributed to several factors, including socioeconomic and cultural issues, lack of access to health care and distrust of the health care system.

John Douglas, director of CDC's Division of STI Prevention, said that the increase in reported chlamydia cases could be attributed to better detection and an increase in testing, especially among women. In addition, providers are now using a more sensitive test to screen for the infection. However, health officials believe that the reported number of chlamydia diagnoses might not be the true number of infections -- which they predict could be closer to three million -- because so many infections go unidentified (Los Angeles Times, 1/14).

The report is available online.