Chlamydia and Gonorrhea are two infections which cause similar symptoms and are usually tested for together.  The US Preventative Services Task Force recommends that all sexually active women younger than age 25 be tested for Chlamydia annually.

In 2010 there were 20115 cases of Chlamydia and 5672 cases of Gonorrhea diagnosed in Indiana.

It is common for people to be infected with Chlamydia for months without any symptoms whatsoever. If a male has symptoms it is typically a discharge from the penis and burning with urination. Women often have a discharge or lower abdominal pain.  Gonorrhea almost always causes noticeable symptoms.  It can cause severe burning with urination and discharge in men, and lower abdominal pain and discharge in women. Both infections are diagnosed with laboratory tests.

Both infections are treatable with antibiotics, which usually cure the infection.  If these infections are not treated they can cause severe illness as well as damage to the reproductive organs which can lead to difficulty getting pregnant.
 
More detailed information about Chlamydia can be found at cdc.gov, and more detailed information about Gonorrhea can be found at cdc.gov as well.