1. Sexually Transmitted Diseases Overview (STDs)
-Sexually transmitted diseases (STDs, venereal diseases)
STDs are sometimes referred to as sexually transmitted infections, since these conditions involve the transmission of an infectious organism between sex partners.
More than 20 different STDs have been identified, and about 19 million men and women are infected each year

2. -Depending on the disease, the infection can be spread through
1- sexual activity involving the sex organs, the anus, or the mouth
2- contact with blood during sexual activity.
3- infrequently transmitted by contact (blood, body fluids or tissue removed from an STD
4-infected person and placed in contact with an uninfected person)
5- people that share unsterilized needles markedly increase the chance to pass many diseases, including STD's (especially hepatitis B), to others. Some diseases are not considered to be officially an STD (for example, hepatitis types A, C, E) but are infrequently noted to be transferred during sexual activity.

3.  Frequently, STDs can be present but cause no symptoms, especially in women (for example, Chlamydia, genital herpes or gonorrhea). This can also occur in some men.
 Health problems and long-term consequences from STDs tend to be more severe for women than for men.
-Some STDs can cause pelvic infections such as pelvic inflammatory disease (PID), which may cause a tubo-ovarian abscess.
- The abscess, in turn, may lead to scarring of the reproductive organs
- which can result in an ectopic pregnancy (a pregnancy outside the uterus), infertility or even death for a woman.

4.  Human papillomavirus infection (HPV infection), an STD, is a known cause of cancer of the cervix.
 Many STDs can be passed from a mother to her baby before, during, or immediately after birth.( vertical transmission .
STDs caused by bacteria
Chancroid (Haemophilus ducreyi)
Chlamydia (Chlamydia trachomatis)
Gonorrhea (Neisseria gonorrhea)
Granuloma inguinale (Calymmatobacterium granulomatis)
Lymphogranuloma venereum (Chlamydia trachomatis)
Syphilis (Treponema pallidum)

5. STDs caused by viruses
Genital herpes (herpes simplex virus)
Genital warts (human papillomavirus virus [HPV])
Hepatitis B and D, and infrequently, A*,C*,E* (hepatitis viruses, types A-E)
HIV/AIDS (human immunodeficiency virus [HIV virus])
(poxvirus)
STD caused by protozoa
Trichomoniasis (Trichomonas vaginalis)
STD's* caused by fungi
(Tenia cruris)*
Yeast infections* (Candida albicans)
STD's caused by parasites
Pubic lice or crabs (Pediculosis pubis)
Scabies*  Sarcoptes scabiei

6. Trichomoniasis,
-common cause of vaginitis.
- It is a sexually transmitted disease,
- caused by the single-celled protozoan parasite Trichomonas vaginalis
- producing mechanical stress on host cells and then ingesting cell fragments after cell death.]
-Trichomoniasis is primarily an infection of the urogenital tract
-the most common site of infection is the urethra and the vagina in women.

7. Symptoms
-inflammation of the cervix (cervicitis), urethra (urethritis), and vagina (vaginitis) which produce an itching or burning sensation.
-Discomfort may increase during intercourse and urination.
- a yellow-green, itchy, frothy foul-smelling ("fishy" smell) vaginal discharge.
- lower abdominal pain can occur.
- Symptoms usually appear in women within 5 to 28 days of exposure.
- men may hold the parasite for some years without any signs (dormant) نائم .
-Some sexual health specialists have stated that the condition can probably be carried in the vagina for years, despite standard tests being negative .

8. -While symptoms are most common in women, some men may temporarily exhibit symptoms such as an irritation inside the penis, mild discharge, or slight burning after urination or ejaculation
Diagnosis
-visually observing the trichomonads via a microscope.
-In women, the examiner collects the specimen during a pelvic examination by inserting a speculum into the vagina and then using a cotton-tipped applicator to collect the sample.

9. Treatment
Treatment for both pregnant and non-pregnant patients usually utilizes metronidazole (Flagyl) but with caution especially in early stages of pregnancy
Complications
increased risk of transmission of HIV.
may cause a woman to deliver a low-birth-weight or premature infant.
increased chances of cervical cancer
in males potentially raises the risks of prostate cancer

10. Prevention
abstinence is the preferred method to avoid sexual contact of this disease.
Safe sex and hygiene practices may also help prevent trichomonas infection.
Wear condoms.
Wash before and after intercourse.
Don't share swimsuits or towels. (Trichomonads survive for up to 45 minutes outside the body.)
Shower immediately after swimming in a public pool.