I would like to know if a person contracted chlamydia, is there a good chance of contracting HIV?
I am asking this question because the number of people with chlamydia is much higher than the people with HIV? Why is that?
It is important to remember that different infections work in different ways. So, just because HIV and chlamydia are infections that are sexually transmitted doesn't mean that they are similar; they are actually quite different organisms that your body responds to in different ways.
For one thing, chlamydia is caused by a unique bacterium (obligate intracellular parasite), called Chlamydia trachomatis. Like bacteria, it can be treated with antibiotics, but like a virus, it requires a living cell for survival and replication. It infects cells that line the mucous membranes of the cervix, urethra, rectum, throat, and eye. While infection often doesn't lead to symptoms, chlamydia infection can cause dischrage, burning when urinating, vaginal bleeding, and itching sensations. It is transmitted by contact with infected secretions.
HIV is caused by a virus, more specifically a retrovirus (a term to describe the way the virus uses RNA and DNA to replicate). HIV is found in bodily fluids of infected persons, and, without treatment, can wreak havoc on the immune system. There is no cure for HIV infection.
There are some basic assumptions in the science of STIs that can be applied to your question. A person who has one STI is at risk for infection with other STIs, including HIV infection. STIs that cause ulcerations or inflammation of mucosal tissue (like chlamydia) are likely to increase one's susceptibility to HIV infection. Most importatantly, detecting and treating symptomatic STIs decreases the rates of HIV transmission in some studies.
It is difficult to draw any kind of meaningful conclusion from the fact that chlamydia infection prevalence (which is as high as 4 million people infected annually) in the U.S. is higher than HIV prevalence. For one, chlamydia has been transmitted sexually among people much longer than HIV has. Chlamydia also seems to be transmitted much easier heterosexually (from female to male) than HIV.