Chlamydia trachomatis is a common sexually transmitted infection (STI) caused by bacteria. You might not know you have chlamydia because many people don't have signs or symptoms, such as genital pain and discharge from the vagina or penis.

Chlamydia trachomatis affects mostly young women, but it can occur in both men and women and in all age groups. It's not difficult to treat, but if left untreated it can lead to more-serious health problems.

Early-stage Chlamydia trachomatis infections often cause few or no signs and symptoms. Even when signs and symptoms occur, they're often mild, making them easy to overlook.

What are the Signs and symptoms of Chlamydia trachomatis infection?

• Painful urination
• Vaginal discharge in women
• Discharge from the penis in men
• Painful sexual intercourse in women
• Bleeding between periods and after sex in women
• Testicular pain in men

Chlamydia trachomatis can also infect the rectum, either with no signs or symptoms or with rectal pain, discharge or bleeding. You also can get chlamydial eye infections (conjunctivitis) through contact with infected body fluids.

Gonorrhea is an STD that can cause infection in the genitals, rectum, and throat. It is very common, especially among young people ages 15-24 years.

How is gonorrhea spread?

You can get gonorrhea by having vaginal, anal, or oral sex with someone who has gonorrhea. A pregnant person with gonorrhea can give the infection to their baby during childbirth.

Sexually active people can get gonorrhea through vaginal, anal, or oral sex without a condom with a partner who has gonorrhea.

If you are a sexually active gay or bisexual man, you should get tested for gonorrhea every year. If you are a sexually active woman, you should get tested for gonorrhea every year if you are:

• Younger than 25 years.
• 25 years and older with risk factors, such as new or multiple sex partners, or a sex partner who has a sexually transmitted infection.

What are the symptoms of gonorrhea? 

Gonorrhea often has no symptoms, but it can cause serious health problems. 

Symptoms can include:

• Painful or burning sensation when urinating
• Increased vaginal discharge
• Vaginal bleeding between periods
• A white, yellow, or green discharge from the penis
• Painful or swollen testicles (although this is less common)

Rectal infections may either cause no symptoms or cause symptoms in both men and women that may include:

• Discharge
• Anal itching
• Soreness
• Bleeding
• Painful bowel movements.

Trichomoniasis (or “trich”) is a very common STD caused by infection with Trichomonas vaginalis (a protozoan parasite). Although symptoms vary, most people who have trich cannot tell they have it.

How common is trichomoniasis?

In the United States, CDC estimates that there were more than two million trichomoniasis infections in 2018. However, only about 30% develop any symptoms of trich. Infection is more common in women than in men. Older women are more likely than younger women to have the infection.

How is trichomoniasis spread?

Sexually active people can get trich by having sex without a condom with a partner who has trich.

In women, the infection is most commonly found in the lower genital tract (vulva, vagina, cervix, or urethra). In men, the infection is most commonly found inside the penis (urethra). During sex, the parasite usually spreads from a penis to a vagina, or from a vagina to a penis. It can also spread from a vagina to another vagina.

It is not common for the parasite to infect other body parts, like the hands, mouth, or anus. It is unclear why some people with the infection get symptoms while others do not. It probably depends on factors like a person’s age and overall health. People with trich can pass the infection to others, even if they do not have symptoms.

What are the signs and symptoms of trichomoniasis?

About 70% of people with the infection do not have any signs or symptoms. When trich does cause symptoms, they can range from mild irritation to severe inflammation. Some people get symptoms within 5 to 28 days after getting the infection. Others do not develop symptoms until much later. Symptoms can come and go.

Men with trich may notice:

• Itching or irritation inside the penis
• Burning after urination g or ejaculating
• Discharge from the penis.

Women with trich may notice:

• Itching, burning, redness or soreness of the genitals
• Discomfort when urinating
• A clear, white, yellowish, or greenish vaginal discharge (i.e., thin discharge or increased volume) with a fishy smell.

Having trich can make sex feel unpleasant. Without treatment, the infection can last for months or even years.

What are the complications of trichomoniasis?

Trich can increase the risk of getting or spreading other sexually transmitted infections. For example, trich can cause genital inflammation, making it easier to get HIV, or pass it to a sex partner.

Syphilis is a sexually transmitted disease (STD) caused by the bacterium Treponema pallidum. Syphilis can cause serious health effects without treatment.

How do people get syphilis?

Syphilis spreads from person-to-person by direct contact with a syphilitic sore, known as a chancre. Chancres can occur in, on, or around the penis, vagina, anus, rectum, and lips or mouth. Syphilis can spread during vaginal, anal, or oral sex. Pregnant people with syphilis also can transmit the infection to their unborn child.

What are the signs and symptoms in adults?

Many refer to syphilis as “The Great Pretender”, as its symptoms can look like many other diseases. However, syphilis typically follows a progression of stages that can last for weeks, months, or even years:

Primary Stage

A single chancre marks the onset of the primary (first) stage of syphilis, but there may be multiple sores. The chancre is usually (but not always) firm, round, and painless. It appears at the location where syphilis enters the body. These painless chancres can occur in locations that make them difficult to notice (e.g., the vagina or anus). The chancre lasts 3 to 6 weeks and heals regardless of whether a person receives treatment. However, the infection will progress to the secondary stage if the person with syphilis does not receive treatment.

Secondary Stage

Skin rashes and/or mucous membrane lesions (sores in the mouth, vagina, or anus) mark the second stage of symptoms. This stage typically starts with the development of a rash on one or more areas of the body. In addition to rashes, signs and symptoms of secondary syphilis may include: fever, swollen lymph nodes, sore throat, patchy hair loss, headaches, weight loss. muscle aches and fatigue

The symptoms of secondary syphilis will go away with or without treatment. However, without treatment, the infection will progress to the latent and possibly tertiary stage of disease.

Latent Stage

The latent (hidden) stage of syphilis is a period when there are no visible signs or symptoms of syphilis. Without treatment, syphilis will remain in the body even though there are no signs or symptoms. Latent syphilis can last for years.

Tertiary Syphilis

Tertiary syphilis is rare and develops in a subset of untreated syphilis infections. It can appear 10–30 years after a person gets the infection, and it can be fatal. Tertiary syphilis can affect multiple organ systems, including the brain, nerves, eyes, heart, blood vessels, liver, bones, and joints.

Genital herpes is an STD caused by two types of viruses – herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2).

What is oral herpes?

HSV-1 often causes oral herpes, which can result in cold sores or fever blisters on or around the mouth but most people with oral herpes do not have any symptoms. Most people with oral herpes get it during childhood or young adulthood from non-sexual contact with saliva.

Is there a link between genital herpes and oral herpes?

Yes. Oral herpes caused by HSV-1 can spread from the mouth to the genitals through oral sex. This is why some cases of genital herpes are due to HSV-1.

How is genital herpes spread?

You can get genital herpes by having vaginal, anal, or oral sex with someone who has the infection. You can get herpes if you have contact with:

• A herpes sore.
• Saliva from a partner with an oral herpes infection.
• Genital fluids from a partner with a genital herpes infection.
• Skin in the oral area of a partner with oral herpes
• Skin in the genital area of a partner with genital herpes.
• You also can get genital herpes from a sex partner who does not have a visible sore or is unaware of their infection. It is also possible to get genital herpes if you receive oral sex from a partner with oral herpes.

You will not get herpes from toilet seats, bedding, or swimming pools. You also will not get it from touching objects, such as silverware, soap, or towels.

Genital herpes is an STD caused by two types of viruses – herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2).

How do I know if I have genital herpes?

Most people with genital herpes have no symptoms or have very mild symptoms. Mild symptoms may go unnoticed or be mistaken for other skin conditions like a pimple or ingrown hair. Because of this, most people do not know they have a herpes infection.

Herpes sores usually appear as one or more blisters on or around the genitals, rectum or mouth. This is known as having an “outbreak”. The blisters break and leave painful sores that may take a week or more to heal. Flu-like symptoms (e.g., fever, body aches, or swollen glands) also may occur during the first outbreak.

People who experience an initial outbreak of herpes can have repeated outbreaks, especially if they have HSV-2. However, repeat outbreaks are usually shorter and less severe than the first outbreak. Although genital herpes is a lifelong infection, the number of outbreaks may decrease over time.

If you touch your sores or fluids from the sores, you may transfer herpes to another body part like your eyes. Do not touch the sores or fluids to avoid spreading herpes to another part of your body. If you do touch the sores or fluids, quickly wash your hands thoroughly to help avoid spreading the infection.

If you are pregnant, there can be problems for you and your unborn fetus, or newborn baby.

Mycoplasma genitalium (MG) is a type of bacteria that can cause an STD. You get it by having sex with someone who has it. Even if you don’t go “all the way” with vaginal sex, you can get MG through sexual touching or rubbing.

Scientists have known about these bacteria since the 1980s, but a recent study showed that more than 1 in 100 adults might have it.

Symptoms

MG doesn’t always cause symptoms, so it’s possible to have it and not know it.

In men, the symptoms are:

• Watery discharge from your penis
• Burning, stinging, or pain when you pee

The symptoms for women are:

• Discharge from your vagina
• Pain during sex
• Bleeding after sex
• Bleeding between periods
• Pain in your pelvic area below your belly button

Mycoplasma hominis is a common mollicute bacteria, present in almost all humans in the urinary tract. However, it can sometimes cause infection which can be transmitted sexually. 

hominis causes septic arthritis and postpartum fever and has been associated with pelvic inflammatory disease and bacterial vaginosis.  

If you're a woman, these bacteria may be linked to pelvic inflammatory disease, an infection of your reproductive organs. They can also lead to problems if you're pregnant, such as:

• Ectopic pregnancy (the embryo grows outside the uterus)
• Early delivery
• Miscarriage
• Mycoplasma hominis can also cause a fever and infection in your newborn baby.

Most healthy women have these bacteria in their cervix or vagina, and a smaller number of men also have them in their urethra. Normally, they don't cause any problems.

Ureaplasma species can cause acute urethritis and have been associated with bacterial vaginosis, preterm birth, and neonatal respiratory disease, and it can spread during sex. If you're pregnant and you're infected, you can pass the bacteria to your baby in the womb or during childbirth.

Some symptoms women can get are:

• It hurts when you pee
• Belly pain
• Pain, odor, or discharge from the vagina
• Swelling at the opening of the urethra

During pregnancy, the bacteria can lead to infections in both the mother and the baby. Problems in newborn babies can include:

• Low birth weight
• Pneumonia
• Bacteria in the blood, called septicemia

Men who are infected can get inflammation of the urethra, called urethritis.

Symptoms include:

• Feeling the frequent or urgent need to urinate
• Difficulty starting urination
• Pain during sex
• Blood in the semen or urine

1. hominis, Ureaplasma urealyticum and Ureaplasma parvum are difficult to grow on cultures (it could take up to 5 days to grow), preferred detection would be with PCR method.