(RxWiki News) It's a silent disease without symptoms. But this STD is quietly infecting more and more young adults around the globe.
Chlamydia infections increased 43 percent over a 14-year span in Finland, a recently published study has found. Certain age groups are getting infected more often than others.
"We found that most of the registered infections occurred among young people. But on the other hand, the cases with newly detected infections were in the older age group," researchers said in their report.
"Get checked for STDs."
The study, led by Erika Wikström, MD, from the National Institute for Health and Welfare and the University of Oulu in Finland, reviewed the number of chlamydia cases reported between 1995 and 2009. Currently, Finland's National Infectious Disease Register does not track the number of tests for chlamydia, although actual diagnoses and the method of testing are accounted for.
And because the disease often comes without symptoms, it can be hard to diagnose.
Researchers looked at almost 150,000 people in the registry with nearly 180,000 chlamydial infections. They divided patients by age into those younger than 23 years, older than 28 and those that fall in between.
The number of first-time diagnoses was tracked each year, as well as the number of times patients were diagnosed a second time. They found that the number of diagnoses increased for both men and women. The rate went up from 3.8 to 5.3 percent among men and 4.9 percent to 7.3 percent among women.
In 2009 specifically, almost a quarter of women and 20 percent of men with the infection were diagnosed a second time. Overall, repeat diagnoses accounted for almost 17 percent of all infections.
Women in their mid 20s had the highest number of repeat infections at almost 37 percent. Men in their late 20s followed behind at about 31 percent. Among those re-diagnoses, more than a third happened within a year.
The rate teenage boys were diagnosed increased almost two and half times over the 14-year span, with 304 new cases in 1995 to 767 more than a decade later. Rates are similar in the US with a 47 percent increase in the number of chlamydia cases between 1999 and 2004.
The authors did not know how often tests for the STD were performed at the coordinating hospitals, which they say may have limited their study.
And with the three-month study span, they also may have underestimated the number of primary and repeated cases of the disease.
The study was published online in the December 2012 issue of the journal Sexually Transmitted Diseases. Helsinki and Oulu University Hospitals, the Finnish Society of Dermatology and Venereology, the Finnish Society Against Sexually Transmitted Diseases and the EU-FP7 PREHDICT Network supported the study.